Sunday, June 19, 2011

Gathering Wild Grains

From the book Lost Crops of Africa:  Volume 1: Grains published by the National Academies Press:

"Over large areas of Africa people once obtained their basic subsistence from wild grasses. In certain places the practice still continues—especially in drought years (see boxes, pages 258 and 264). One survey records more than 60 grass species known to be sources of food grains.2
Despite their widespread use and notable value for saving lives during times of distress, these wild cereals have been largely overlooked by both food scientists and plant scientists. They have been written off as ''obsolete"—doomed since hunting and gathering started giving way to agriculture thousands of years ago. Certainly there has been little or no thought of developing wild grains as modern foods.
This deserves reconsideration, however. Gathering grains from grasslands is among the most sustainable organized food production systems in the world. It was common in the Stone Age3 and has been important almost ever since, especially in Africa's drylands. For millennia people living in and about the Sahara, for instance, gathered grass seeds on a grand scale. And they continued to do so until quite recently. Early this century they were still harvesting not insignificant amounts of their food from native grasslands.
However, in previous centuries the grains of the deserts and savannas were harvested in enormous quantities. In the Sahel and Sahara, for example, a single household might collect a thousand kilos during the harvest season.4 The seeds were piled in warehouses by the ton and shipped out of the region by the caravan-load. It was a major enterprise and a substantial export from an area that now has no equivalent and is often destitute."
If possible in relatively recent centuries, why not during the stone age?

By the way, in prehistoric sites the evidence points to consumption of sorghum, a gluten-free grain, at about 100,000 years before present

If so, then what about leading up to that?  Evolutionary explanations generally involve gradual changes over long periods of time.  A species generally does not change its means of subsistence suddenly, or even over a few millennia.   Adaptation to a new niche (if truly new) generally takes a very long time.

The hypothesis that grains were hardly ever consumed before about ten thousand years ago suffers from lacking a plausible explanation for why and how a species never adapted or even interested in cereal grains would so suddenly (on an evolutionary time scale) adopt a totally new behavior and means of subsistence.

Supposedly gathering grains would be a poor time investment for a forager.  Put to the experimental test, this turns out to be untrue.  From Kislev et al, "Impetus for sowing and the beginning of agriculture: Ground collecting of wild cereals" [1 full text]:

"We found that hand gathering of wild barley and emmer spikelets from the ground in Korazim and Mount of Beatitudes (Israel) is simple and efficient. About 0.25–0.5 kg (0.337 kg on the average) of pure grain could be gathered per hour by a single person, which provides on the average between a half and a whole day of the nutritional requirements for an adult individual."
So, in one to two hours a forager could collect enough wild grain to feed himself for a day, just collecting it off the ground by the handful.  Eight hours of collecting could supply him with grain for a whole week.  A smart forager would quickly come up with ways to make the work easier and more efficient.  Kislev et al continue:

"Our results are in accordance with Harlan, who, after experimental hand stripping of pre-full-ripe ears of wild einkorn at Karacadag, southeast Turkey, claimed that in three weeks, a family group could gather more grain than it could possibly consume in an entire year (28)."
Three weeks investment for more food than you can eat in an entire year doesn't count as optimal foraging?  More from Kislev et al:

"The significance of recognizing the practicality of spikelet gathering from the ground is that the gathering of large-seeded cereals as a staple food is not restricted to early summer. Rather, it can continue throughout the summer into the autumn, July through October, when the first heavy rains arrive and the dispersed grains begin to sprout. In other words, the collecting of grains from the ground would supply hunter-gatherers with a ready source of vegetal food until October, when acorns, their second most important plant resource, matured (29). The availability of acorns in October enabled them to invest part of the harvested grains for sowing. Moreover, stored grains and acorns would have provided nourishment until the following summer. There would then have been no period of vegetal food shortage due to seasonality of the two major harvests that helped support human groups in Western Asia at least from the beginning of the Upper Palaeolithic."

Has the bubble burst yet?

Put this together with evidence that Paranthropus boisei, a human relative dating to 1.4 to 1.9 million years ago,  grazed on grass [2].  Paranthropus and humans both descended from Australopithecus, but the Paranthropus went extinct.  To several scientists working with this information, this new data on Paranthropus suggests a reinterpretation of previously collected data on Australopithecine diet, i.e. that Australopithecus may also have eaten grasses.

Perhaps we can start to put together a plausible path for the incorporation of cereal grains--grass seeds--into human diets.  Perhaps human ancestors used grasses as food more than 2 million years ago. Human evolution might look something like this: the grass-eaters went extinct, but the grass-seed eaters thrived.

The Progression of Disease According to Oriental Medicine: Part 1


Warning:  This series of blogs presents an alternative Chinese-scientific perspective on the development of disease.  I won't and can't provide 'research' to back everything largely because modern scientists have not shown much interest in understanding the directly observable marks of deteriorating health, due to their entrancement by laboratory tests which may distract them from direct observation of the people they attempt to help.

In the Yellow Emperor’s Classic of Internal Medicine (Huang Di Nei Jing), Qi Bo, the emperor’s personal physician, says (paraphrased): 


“Those who wait to treat disease until it has already arisen are like those who wait until they are thirsty to dig a well, or wait until they are in battle to forge weapons.  Are not these actions too late?”


Due to this preventive perspective, for several thousand years of development Chinese physicians focused on identifying early signs of imbalance so that they could take actions to avert health disasters by adjusting their own, and their patient’s diets and lifestyles.   Perhaps as a consequence, famous traditional Chinese physicians had extraordinary healthy lifespans for their times.    For example:

Dr. Sun Su Mao (Ssu-Mo) (581-682) – lived 101 years, an impressive feat for the 6th century.  He once said “Anyone over 40 years old should try to avoid laxatives, which will weaken his body, and begin to take tonics.  Anyone over 50 years old should take tonics all year round; such are the secrets of nourishing life to enjoy longevity.”

Dr. Meng Shen (621-713) – lived 92 years.  He once said “A person who really knows how to nourish the body should always keep good foods and herbs handy.”

Dr. Luo Ming Shan (1869-1982) lived 113 years.

In Chinese Foods for Longevity, Henry Lu points out that according to Outstanding Chinese Physicians in the Past and their Medical Theories published by Peking College of Chinese Medicine in 1964, the 37 most outstanding Chinese physicians between 581 CE and 1964 CE had an average lifespan of 80.56 years.

Many of these guys lived well before the 18th century, yet, on average they lived 10 years longer than the average modern citizen of modern industrialized nations.

Over the millennia of its development,  due to their considering dietetics one of the essential branches of medicine, Chinese physicians realized that many supposedly ‘minor’ symptoms arise from dietary imbalances, and that if left unchecked the process producing these 'minor' symptoms would eventually produce a major disease.  Gradually this came to formulation as an understanding of how the bodymind (Chinese medicine considers mind and body as one unit) progresses from minor to major diseases based on an imbalance between dietary intake and elimination or expenditure.

The Chinese perspective rests on the realization that to maintain homeodynamics (health) the bodymind must have just the right amount of nutrition, neither too much nor too little.  Like Plato, ancient Chinese physicians noticed a clear division of disease incidence between wealthy aristocrats and ordinary peasants.  

So long as they had adequate quantity and variety of simple plant foods and a little animal products, the peasants remained lean, healthy and fit and had long lives.  If they suffered food shortages, often due to excessive taxation (taxes were paid in bushels of grain) by overlords, they developed deficiency diseases marked by infectious disease susceptibility, weakness, wasting,  mental and physical listlessness, and pallor. 

In contrast, among wealthy and overfed overlords who used some of the grains procured by taxation to produce grain-fed animal products for their own feasting, physicians saw diseases of excess marked by abnormal accumulations:  obesity, diabetes mellitus (identified by Chinese physicians by 700 AD,  900 years before Europeans), tumors, restlessness, tension, and sluggishness.

This led the Chinese philosopher-physicians to both political and medical conclusions.  On the political side, they vigorously opposed taxation, as recorded in the Tao Te Ching and many works of Confucius, Mencius, and other so-called Confucians:

"Human hunger is the result of overtaxation; For this reason, there is hunger."  Tao Te Ching Chapter 75

They also developed a unique view of the role of the physician, and identified three ranks of physicians:

Lower doctors:  Those who treat and heal sicknesses symptomatically but do not treat the whole personality of the patient or guide to a healthy lifestyle.
Middle doctors:  Those who treat and heal by guiding the patient to change his or her personal habits and attitudes, including diet, exercise, meditation, and ethics.
Highest doctors:  Those who treat and heal the sicknesses of society, nation, and world through philosophy and education to align self with others, and humanity with nature. 

The "Confucian" Classic of Great Learning encapsulates some of the central tenets of "higher medicine" as conceived by Chinese philosopher-physicians.

On the medical side, by treating both the wealthy and the poor, Chinese physicians developed a clear understanding of how disease develops. 

On the one hand, deficiency of intake relative to requirements (elimination and expenditure) will create deficiency diseases, and on the other hand, excessive intake relative to requirements will create diseases of excess, accumulation, congestion, blockage, and stagnation. Chinese philosopher-physicians saw this process occurred whether talking about diet (excess or deficiency of food) or other matters (excess or deficiency of clothing, shelter, possessions, etc.).  

To the Chinese, health, whether personal, mental, social, or political, could arise only through achieving the Golden Mean, a concept held in common with Aristotle.

These days, in modernized industrial nations, a majority of the people live like the royalty of the past, with plenty of rich food to eat.  Consequently, people in modern industrialized nations suffer primarily from nutritional excess diseases such as obesity (accumulations of body fat), diabetes (excess fat and sugar in the blood), cardiovascular diseases (accumulations, congestion, and blockage of blood vessels causing stagnation of blood circulation), neurological diseases involving accumulation of plaque (Alzheimer’s, multiple sclerosis), and numerous others. Among affluent populations, deficiencies occur almost always in a context of excesses.

Oriental medical theory maintains that in most cases these late stages of psychophysical degeneration are preceded by a long gradual process of apparently minor alterations in health that herald the oncoming or eventual disaster and offered opportunities for self-correction.   Chinese physicians taught their patients to stay aware of this process and to self-correct using food therapy.  

However, one must understand that these food therapy methods work well only in the context of the basic healthy diet developed and integrated into Asian cuisine:  starch-based, low in fat and animal products, rich in colorful vegetables.  You can't overturn the ill effects of a very imbalanced diet by adding a few servings of a medicinal food.  

Basically, if you understand how disease progresses from minor to major, you can interrupt the process before it becomes so deeply rooted that you will have trouble correcting it with natural approaches.  Updated application of this perspective using traditional Chinese medical theories (yin-yang, Eight Principles, and Five Transformations) can easily incorporate and make sense of otherwise inexplicable medical findings, such as why many people with skin disorders have a history of respiratory allergies or asthma as well.    

In outline form, the progression looks like this:

1. Health:  Balanced intake and normal discharge
2. Abnormal discharge and general fatigue
3. Impairment of blood circulation and aches and pains
4. Impaired blood quality with chronic discharge
5. Accumulation of excess material in circulation
6. Storage of excess material in various compartments
7. Nervous disorders
8. Diseases of mind and spirit, summed as self-delusion

1. Healthy condition: Balanced Intake and Discharge
We take in nutrients from foods and beverages as well as influences from climate (hot, cold, damp, dry) and social environment (emotions, sounds, colors, etc.).  All of these inputs have some effect on our physiology.  To maintain health we have to retain what we need and discharge any excess.

We all transform or discharge inputs through respiration, perspiration, urination, defecation, and physical and metal activities. Women have additional avenues of discharge through menstruation, parturition, and lactation.
 
Every physical or mental activity we express reflects the quality of what we have ingested.

Accordingly, in addition to climate, time and place, diet exerts an influence on culture through its psychophysical effects on the creators/participants.  Thus, different climates and diets produced different historical qualities of art, music, architecture, literature, games, sports, etc..  For example, the traditional Chinese diet produced people who resonated with the traditional Chinese music, the Indian diet produced people who resonated with traditional Indian-style music, and the diet of certain youth in the U.S. produced people who resonated with heavy metal rock.  

What comes out reflects what went in.


 2. Excessive intake and abnormal discharge.

If from a healthy state you ingest or inhale or otherwise absorb an input that supplies something that exceeds the bodymind’s needs and the capacity of normal routes of discharge, the bodymind will manifest alterations of function, most moving the excess input out of the body, such as:
  • coughing and sneezing
  • more frequent defecation
  • more frequent urination
  • increased and spontaneous sweating and sudden rashes
  • fidgeting, tapping, muscle spasms and tension, acute hyperactivity
  • rapid blinking
  • irritability, anger
  • anxiety, excitability

The more extreme the imbalance of intake, more extreme the output, such as:  shivering, trembling, nausea, vomiting, crying, shouting, screaming.

The input here could include healthy food (subtle reactions), spoiled food or an allergen (strong reactions), or traumatic experience like witnessing some aweful crime, losing a loved one, or enduring a natural disaster, among many other possibilities. 

Chinese physicians did not recognize a dichotomy of body and mind, nor did traditional Western physicians or culture. Chinese physicians watched the development of internal organ disorders and saw mental and emotional effects of those disorders, and also the reverse, that sudden emotions resulted in altered operations of internal organs.  They correlated fear with the kidneys, anger with the liver, joy with the heart, rumination with the digestive system, and grief with the lungs, by noticing how emotions affected or were affected by the organs.  

So for example, in fear people may lose control of urination, in anger they may get indigestion marked by reflux, bloating and pain, rumination can destroy the appetite, overjoy (excitement) can affect heart rate and strength, and grief affects respiration (sobbing).

 In English, we still have words reflecting this ancient understanding.  For example, an disrespectful person "has the gall,"  referring originally to an imbalance of the gall bladder,  a depressed person has 'melancholy,' an imbalance of the bile (chol-), and an aggressive or angry person is 'bilious' or 'choleric,' again, an imbalance of the bile, or liver/gallbladder system [1].  And how about being "pissed off" and "so scared I shit my pants"?  Chinese medicine has a way of physiologically understanding the actual experiences that gave rise to these locutions as well.

I know, where are the 'studies' to support this?  I don't know of any, yet.  Chinese physicians discovered that eating animal liver would treat night blindness hundreds of years before laboratory science discovered retinol (vitamin A) and showed that night blindness results from retinol deficiency.  If they had waited for double-blind, placebo-controlled studies and modern biochemistry to confirm that eating animal liver treats night blindness, thousands of people would have gone blind from deficiency over the years.  

Modern laboratory and clinical science creating 'top-down' knowledge only studies a quite small part of reality and moves very slowly compared to empirical discovery growing from 'bottom-up.'

Check your own experience. For my part, I see these relationships in my clinic on a daily basis.

Anyway, these signs, among others, indicate that the specific organ(s) have taken the brunt of the dietary excess:
• A tendency to obsessive thinking, rumination, whining, complaining can indicate an overload of the digestive system.
• A tendency to anger, impatience, or shouting can arise from an overload of the liver and indecision can arise from an imbalance of the gall bladder.
• A tendency to anxiety and fear can arise from an imbalance affecting the kidneys, urinary bladder, or endocrine system.
• A tendency to fall into crying or grief can indicate an imbalance affecting the lung or large intestine.
• A tendency to nervousness, hyperexcitability, or inappropriate laughter can indicate an imbalance affecting the heart.

At this stage of imbalance we may also feel general fatigue resulting from the burden placed on body organs by the overload of input. 

At this stage of disease, recovery requires removal of the dietary and other causes, and improvement of diet and exercise.  Since the imbalance does not have deep roots, it may take only several hours to several days to recover.

I'll go through the  rest of the stages in future posts.

Friday, June 17, 2011

Micronutrient Comparison: High fat vs. High carb; Plus: Ancient Greek Diet and Diseases

A reader emailed me asking, in his words:

"I would love to hear what your current diet includes, how you get enough vitamins/minerals on a relatively low protein/fat diet and if you have any good resources on what a traditional western diet would include."

So I thought I would do a little post on this topic.

My Current Diet

My current diet includes, ranked from highest to lowest volume:

1.  Starches:   brown rice, oatmeal, sorghum, whole corn tortillas, sweet potatoes, white potatoes, yucca root, kabocha squash, occasional white rice

2. Vegetables:  various greens, onions, carrots, radishes, celery, tomatoes, etc.

3.  Fruits:  Apples, oranges, berries, grapes, etc.

4.  Animal products:  mostly fish and shellfish (almost daily) > eggs > poultry ( a few times in the past month) > red meat (once in the past two weeks); total of 3-6 ounces daily (one egg substituting for one ounce)

5. Some soy products:  tofu and soy milk (total of a few times a week)

6. Very small amounts of olive oil and flax oil (1-3 tsp. daily)

Where Are Those Vitamins and Minerals?

Now, on to the question, how can anyone get adequate vitamins and minerals on a low protein/low fat diet?

Let's take a look at two menus I created, each about 2400 kcal, for a moderately physically active male of about 150-160 pounds, one low in animal products and fat, the other high in animal products and fat.

Here's the one low in animal products and fat, about 64/14/21 carb/pro/fat percent energy, with the micronutrient analysis; take note of the quantities of rice, potatoes, and sweet potatoes; this is the way I eat:


The menu has 100 g protein, more than enough to sustain muscular growth for anyone weighing up to 100 kg.  It exceeds all of FitDay's standard requirements for micronutrients except calcium where it reaches 86% of the 1000 mg standard.  In fact this also exceeds the requirements of most people; research has shown that the actual average requirement for calcium is only about 740 mg per day [1, 2 full text], so this menu exceeds the requirement.

Just a brief note on quantity:  In my experience, when people try low-fat diets, they don't consume anywhere near enough food to satisfy energy requirements.  They feel hungry, and they erroneously conclude that eating carbs makes them hungry, when in reality, they are hungry because they aren't eating enough quality starch.  Asians eat an average of 1/2 to 1 pound of rice (precooked weight) daily [full text], plus other grains, potatoes and other starches, with people eating lesser amounts of animal products eating the higher amount of rice.

To create the high fat menu, I took the above menu and removed all the starchy foods (brown rice, oatmeal, and potatoes), leaving in one sweet potato (the starch with the highest nutrient density), getting the carbs down to 100 g, then added bison and increased the meat and fish portions so that the total menu would supply protein equivalent to the above low-fat menu.  I kept the same non-starchy, high nutrient density vegetables and fruits as in the low-fat menu so as to minimize difference.  Then I added approximately equal portions of olive oil and butter to get the kcalorie count up to 2400, same as the other menu.  The macronutrient ratio came to 15/16/68 carb/pro/fat % energy (about the opposite carb/fat ratio to the low-fat menu).  Here's the menu and micronutrient analysis:


This menu has 200 mg less calcium than the low-fat menu, failing to meet even the new standard of ~740 mg, and fails to supply the RDA for magnesium, potassium, zinc, thiamin, and pantothenic acid.  The following table compares the two menus relative to the RDA for the listed micronutrients.  Red numbers indicate values that fall below the RDA:


Nutrient
Low-Meat, Low-Fat
%RDA
High-Meat, High-Fat %RDA
Highest Level
LM or HM
Vitamin A
761
839
HM
Vitamin B6
336
188
LM
Vitamin B12
254
329
HM
Vitamin C
523
458
LM
Vitamin D
262
266
=
Vitamin E
108
164
HM
Calcium
86
60
LM
Copper
386
167
LM
Iron
250
176
LM
Magnesium
175
61
LM
Manganese
543
135
LM
Niacin
160
108
LM
Pantothenic Acid
225
87
LM
Phosphorus
270
151
LM
Potassium
124
75
LM
Riboflavin
124
125
=
Selenium
137
285
HM
Thiamin
209
74
LM
Zinc
111
79
LM



1.  Despite retaining the high-nutrient density vegetables and fruits, the high-meat, high-fat, low-carb menu fails to provide the RDA for six of nineteen nutrients (32%).  This occurred while including 100 g nutrient-dense sources of carbohydrate daily.  If I cut the carbs further, the menu would get even weaker in micronutrients. Could this explain why Atkins Nutraceuticals exists?

2.  The low-meat, low-fat menu supplies the higher amount for 13 of 19 nutrients, the high-meat, high-fat menu supplies the higher amount for only 4 of 19 nutrients, and the two menus have approximately equal amounts for two nutrients.

So, I get my nutrients by eating nutrient-dense plant foods.  Even though I included some of the most nutrient-dense of plant foods in the high-fat menu, it didn't match the nutrient-density of the low-fat menu.  So I can turn the question around now and ask, how does one get adequate vitamins and minerals eating a low-carbohydrate, high-meat, high-fat diet?

Traditional Western Foods

Try reading about ancient Greek diet:

"Cereals formed the staple diet......The cereals were often served accompanied by what was generically referred to as ὄψον opson, "relish".[26] The word initially meant anything prepared on the fire, and, by extension, anything which accompanied bread.[27] In the classical period it came to refer to fruit and vegetables: cabbage, onions, lentils, sweet peas, chickpeas, broad beans, garden peas, grass peas, etc.[28] They were eaten as a soup, boiled or mashed (ἔτνος etnos), seasoned with olive oil, vinegar, herbs or γάρον gáron, a fish sauce similar to Vietnamese nước mắm. According to Aristophanes,[29] mashed beans were a favourite dish of Heracles, always represented as a glutton in comedies. Poor families ate oak acorns (βάλανοι balanoi).[30] Raw or preserved olives were a common appetizer.[31]

Among the ancient Greeks, the wealthy ate substantial animal products but the peasants did not. Before you follow their example, you might want to know something.  This dietary division of the classes gave ancient Greek philosophers and physicians the opportunity to observe a distinct division of health between the classes. In describing the mode of life of the citizens of The Republic, Socrates says:

"They will feed on barley-meal and flour of wheat, baking and kneading them, making noble cakes and loaves; these they will serve up on a mat of reeds or on clean leaves, themselves reclining the while upon beds strewn with yew or myrtle. And they and their children will feast, drinking of the wine which they have made, wearing garlands on their heads, and hymning the praises of the gods, in happy converse with one another. And they will take care that their families do not exceed their means; having an eye to poverty or war......of course they must have a relish-salt, and olives, and cheese, and they will boil roots and herbs such as country people prepare; for a dessert we shall give them figs, and peas, and beans; and they will roast myrtle-berries and acorns at the fire, drinking in moderation. And with such a diet they may be expected to live in peace and health to a good old age, and bequeath a similar life to their children after them."[2, 3]

Glaucon protests that this substantially plant-based diet seems fit only for pigs, that the people should have "sauces and sweets in the modern style." Socrates retorts that doing so will create a "State at fever heat" and goes on:

"Now will the city have to fill and swell with a multitude of callings which are not required by any natural want; such as the whole tribe of hunters and actors, of whom one large class have to do with forms and colours; another will be the votaries of music--poets and their attendant train of rhapsodists, players, dancers, contractors; also makers of divers kinds of articles, including women's dresses. And we shall want more servants. Will not tutors be also in request, and nurses wet and dry, tirewomen and barbers, as well as confectioners and cooks; and swineherds, too, who were not needed and therefore had no place in the former edition of our State, but are needed now?  They must not be forgotten: and there will be animals of many other kinds, if people eat them."[3]

To which Glaucon says: "Certainly."

And Socrates says:

"And living in this way we shall have much greater need of physicians than before?"

To which Glaucon says:  "Much greater."  

In other words, Plato or Socrates had already observed, more than 2000 years ago, that the rich people eating their rich diet had affluent diseases and early mortality, and the peasants eating a frugal diet could expect "health to a good old age."  

I referred to this, among other ancient writings, when I wrote "the currently popular concept of paleo diet—animal-based, relatively high in protein and fat and relatively low in carbohydrate—conflicts with empirical nutrition knowledge accumulated over the course of 5 thousand years in both Asian and Western medicine"[4].  The knowledge that humans thrive on low-fat plant-based nutrition and get sick on high-fat animal-based nutrition is not some 20th century aberration in the West; we find it expressed by the very founders of Western civilization. 

I just find it uncanny that modern mainstream Western nutrition research seems to be reaching the same general conclusions about optimal human nutrition as Plato/Socrates, traditional Chinese medicine, and traditional Ayurvedic medicine, despite coming at the question from different angles in different ages and in different populations.

The irony:  Armed with their so-called 'scientific' method, which they haughtily consider superior to any previous method of discovery, a team of modern scientists climbs the mountain of Truth and when they get to the top, they find the best ancient philosophers and physicians from East and West have been sitting there for millennia. 


  





Wednesday, June 15, 2011

Effect of dietary fat on satiation within and between meals

Blundell et al performed a series of four experiments to determine the effect of fat content of a meal on satiety, both during and after meals. [1 full text ]

The first  experiment involved giving 16 lean, healthy subjects a standard breakfast of 440 kcal, or the same breakfast supplemented with either fat or carbohydrate calculated to provide ~360 kcal.  The standard breakfast consisted of orange juice, scones, and fruit yogurt.  The supplements consisted of either polyunsaturated margarine and cream, or a combination of sucrose, maltodextrin, and glucose.  The following table provides the data on the three types of breakfasts:


Each individual tested each breakfast with a one week interval between tests.  The subjects rated the palatability of the meals, and rated hunger, desire to eat, fullness, and prospective consumption before the breakfasts and periodically during the rest of the day.

After the breakfasts, the subjects ate measured meals, provided by the experimenters, for lunch and dinner on the same day, and kept weighed food records for the period between dinner that day and breakfast the next.

In this experiment, neither the high fat nor the high carbohydrate breakfasts appeared to exert any significant effect on intakes of macronutrients at the subsequent lunch or dinner.  However, subjective reports of hunger did differ between the high carbohydrate and high fat meals.   Specifically, the subjects reported less hunger with the carbohydrate-supplemented meal compared to the baseline or fat-supplemented breakfasts.  The following figure depicts the effects:



When the subjects ate the carbohydrate-enriched breakfast, they experienced less post-meal hunger than when given the fat-enriched breakfast, indicating that they found fat less satisfying than carbohydrate during the post-ingestive phase. 

In the second experiment, 12 lean healthy individuals consumed the same breakfasts given in experiment one, followed by a snack provided 90 minutes after the breakfasts.  Subjects rated themselves as less hungry and more full after the carbohydrate-enriched breakfasts, compared to the fat-enriched breakfasts.   They also ate smaller snacks at the 90 minute mark when they had the carbohydrate-enriched breakfast, compared to when they ate the fat-enriched breakfast.  The following figure depicts the effects:



In the third experiment, 16 lean healthy subjects consumed the same breakfasts as in experiment one, followed by a snack 90 minutes after the breakfast, or a meal 270 minutes after the breakfast.   The following table depicts the results:


When given the carbohydrate-enriched breakfast, the subjects  voluntarily ate a smaller snack at 90 minutes after, compared to what they ate after the fat-enriched breakfast.  Of interest, although the fat-enriched breakfast supplied ~800 kcal, 90 minutes after that breakfast they voluntarily consumed a snack the same size as they had 90 minutes after the 440 kcal baseline breakfast.  This means that at 90 minutes after the breakfast, the 800 kcal breakfast providing 57% energy from fat was no more satisfying than the 440 kcal breakfast providing only 10% energy from fat.  

The greater satiating effect of the high carbohydrate breakfast disappeared at 270 minutes.  Blundell et al attributed the greater satiating effect of the carbohydrate-supplemented breakfast at 90 minutes to the greater elevation of blood glucose achieved by the carbohydrate-rich breakfast.  As the glucose was oxidized or stored over the next 180 minutes, this satiating power declined.

In the fourth experiment, 12 obese women ate either one of two lunches, each on two different occasions.  One lunch supplied 527 kcal, the other supplied 985 kcal.  Between lunch and dinner, the subjects rated their hunger at one hour intervals.  At dinner, each woman was offered either foods supplying 50% of energy as fat, or 50% of energy as carbohydrate and allowed to eat as much as desired.  So, each woman had four different procedures:

1.  A 527 kcal lunch, followed by an ad libitum high-fat, low-carbohydrate (50% energy as fat) meal for dinner.
2.  A 527 kcal lunch, followed by an ad libitum low-fat, high-carbohydrate (50% energy as carbohydrate) meal for dinner.
3.  A 985 kcal lunch, followed by an ad libitum high-fat, low-carbohydrate (50% energy as fat) meal for dinner.
4. A 985 kcal lunch, followed by an ad libitum low-fat, high-carbohydrate (50% energy as carbohydrate) meal for dinner.

Not surprisingly, the size of the mid-day meal determined the course of subjective hunger during the afternoon, i.e. the smaller meal was followed by earlier return and greater intensity of hunger as depicted in the following figure:



However, the size of the midday meal did not affect the energy content of the ad libitum dinner meal as much as the relative fat and carbohydrate contents of the offered dinners.  The following table displays the impact of midday meal size and dinner composition on satiation during the dinner meal:

Regardless of whether given the high-energy or low-energy midday meal, the subjects consumed an average of 5.6 MJ/1336 kcal for dinner when given high-fat foods, but only 2.8MJ/677 kcal when given the high-carbohydrate/low-fat foods.  This demonstrated that within a meal, high-carbohydrate foods appear to have a greater satiating effect, i.e. subjects voluntarily consumed less food energy when given a high-carbohydrate selection compared to when given a high-fat selection.

Since the high-fat meal was at least 50% energy from fat, and the average intake was 1336 kcal, this means the average intake of non-fat nutrients at the high-fat meals was at most 668 kcal, approximately the same as the 677 kcal the women consumed when eating the low-fat high-carbohydrate meals. It appears as if the women were eating to achieve a certain intake of non-fat nutrients (carbohydrate or protein), regardless of the fat content of the food.  Since the high-carbohydrate meals supplied more carbohydrate and protein per ingested gram of food, the apparent carbohydrate or protein drive was satisfied with less total fat and energy intake.

The researchers followed the food intake of these women after dinner and throughout the next day as well.  Some would predict that the high fat intake of the high-fat meal would reduce post-meal and next-day food intake.  That did not happen.

 The women consumed after-dinner snacks averaging 310 kcal after the high-fat meal, and 391 kcal after the low-fat, high-carbohydrate meal.   The 81 kcal lower energy intake is insignificant compared to the nearly 700 kcal greater kcal intake at the preceding high- meal. 

The day after having the high-fat dinner, the women consumed an average of 1800 kcal, whereas the day after having the low-fat dinner, the women consumed an average of 1556 kcal.  This ~250 kcal difference did not reach statistical significance, but the direction was opposite of the prediction that they would compensate for the high-energy intake of the previous day by reducing energy intake in subsequent days.  It may even suggest that the high-carbohydrate dinner had a satiating effect that lasted into the next day. 

Now, looking at this from an evolutionary perspective:  If humans find carbohydrate more satisfying than fat, this suggests that evolutionary diets were high in carbohydrate and low in fat.  An organism geared to consuming fat would get the most satisfaction from fat.  An organism geared to consuming carbohydrate would continue eating until it either satisfied its carbohydrate requirement, or reached the limit of  its ability to convert protein or glycerol to carbohydrate, whichever comes first, regardless of “energy” intake--exactly as seen in these women. 

Since the brain regulates eating behavior and it primarily relies on glucose as its main fuel, we can reasonably expect that the brain has a carbohydrate drive, meaning that it drives people to eat until they ingest adequate glucose, or enough protein to provide the brain with adequate glucose.   

In other words, I would predict that, barring interference from the conscious mind (i.e. so-called "discipline") attempting to control macronutrient ingestion,  hungry people will keep eating until they at least minimally satisfy their carbohydrate requirements either directly from dietary carbohydrate, or indirectly from dietary protein, or until in the latter case they reach the limit the body imposes on protein ingestion, whichever comes first, regardless of total fat (or energy) intake.

Several studies appear to indicate that primitive Eskimo diets aligned with this prediction.  Several studies have indicated that Eskimos consume  very high percentage of energy as protein [Table from 2 full text ]:


On average these studies suggest that free living Eskimos derive 48% of energy from protein.  Assuming a 3000 kcal diet for an active male, this would be 1440 kcal/360 g of protein daily.  Since the human protein (70 kg reference man) requirement ranges from 50 to 75 g per day under most circumstances, these data indicate that the Eskimo may consume ~300 g excess protein daily.  According to Jungas et al, about 58% of catabolized protein will appear in the blood stream as glucose [3 ] .  Therefore, an Eskimo consuming about 300 g excess protein daily will generate from this about 174 g glucose, approximately the minimal amount required by the central nervous system. 

Some have criticized the data in the table above claiming that Eskimos eat ~80% of kcalories as fat based on claims made by Stefansson.  I find it extremely unlikely that four separate investigations produced incorrect data on Eskimo macronutrient consumption, and since Stefansson did not directly measure the macronutrient intake of Eskimos, I see no reason we should accept his estimate as more accurate.

The idea that Eskimos couldn’t have eaten a diet providing 48% of energy as protein is based on the claim that a protein intake of this magnitude will lead to so-called “rabbit starvation” from excess protein intake.  About “rabbit starvation” Cordain et al [4 ] have written:

“Excess consumption of dietary protein from the lean meats of wild animals leads to a condition referred to by early American explorers as “rabbit starvation,” which initially results in nausea, then diarrhea, and then death (39). Clinical documentation of this syndrome is virtually nonexistent, except for a single case study (42). Despite the paucity of clinical data, it is quite likely that the symptoms of rabbit starvation result primarily from the finite ability of the liver to up-regulate enzymes necessary for urea synthesis in the face of increasing dietary protein intake.” [Emphasis added]

Aside from the fact that clinical documentation of “rabbit starvation” is “virtually nonexistent,” Shaefer reported that primitive Eskimos on native diets had enlarged livers in comparison to Caucasians, and when they reduced protein intake, substituting carbohydrate, their livers reduced in size [5, full reference below].  This may suggest that Eskimos on native diets had livers adapted to chronically very high protein intakes via hypertrophy, whereas explorers (including Stefansson) may have experienced acute “rabbit starvation” when forced to eat very lean meat because unlike Eskimos they did not have previous lifelong exposure and hepatic adaptation to very high protein intakes.  

A Word About Protein And Satiety

A number of studies have shown that when given energy-restricted diets, people find higher protein intakes more satiating (within meals) and satisfying  (between meals) than lower protein diets.  For a while I felt impressed by this, thinking that protein is more satiating than any other nutrient. 

However, I now think this finding simply reflects the long-known fact that when when we restrict total food energy intake, and therefore carbohydrate intake, protein requirements increase, because carbohydrate restriction increases the use of lean mass to produce glucose.  Thus, under hypocaloric conditions, a drive to meet increased protein requirements--what we might call "protein hunger"-- may surface. 

Again, it has been known for a long time that protein requirements increase under hypocaloric conditions, so these recent studies showing higher protein diets to be more satiating under hypocaloric conditions appear to me to just be late application of something we have known for decades.  These findings do not mean that protein is the most satiating nutrient under all conditions.  I performed a quick PubMed search for studies of the satiating effects of protein under ad libitum conditions, and found only one study  [6 abstract ] which reported both "higher protein led to greater daily fullness" and "Protein quantity did not influence daily hunger, glucose, or insulin concentrations," i.e. inconsistent effects.


Given what we know about the satiating power of carbohydrate and protein, and fat balance versus energy balance, Astrup suggests that the optimal diet for reducing body fat might be very low in fat, high in carbohydrate, and moderately high in protein, for example 60-65/20-25/15 carbohydrate/protein/fat [7 abstract, 8 full text].

Take Home

1)  This series of clinical studies found that both lean and obese people not invested in consciously controlling their macronutrient intakes experienced most satisfaction and less hunger from high-carbohydrate than from high-fat meals.
2) The biological basis for this probably lies in the brain's demand for glucose.  The brain drives eating behavior, and since it prefers glucose to other fuels, it has a drive to satisfy its own requirement for glucose.
3)  Barring conscious control of macronutrient intake/ratios, a majority of people probably will eat to achieve an adequate intake of carbohydrate, either by consuming carbohydrate directly, or by consuming enough protein to produce adequate carbohydrate, continuing to eat until either they satisfy their carbohydrate drive, or they meet the limit of the body's ability to convert protein to carbohydrate, whichever comes first, and regardless of total energy intake. 
4) If people choose high-fat foods to satisfy carbohydrate requirements, they will very likely consume more fat (grams) than they can burn in a day, leading to progressive gain of fat weight.

Notes:

5. Schaefer O. Eskimos (Inuit). In: Burkitt DP, Trowell HC, eds. Western Diseases: Their Emergence and Prevention. Cambridge, MA:  Harvard University Press, 1981:114.

Tuesday, June 14, 2011

Farewell To "Paleo"

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I have experimented with eating a so-called “paleo” diet for at least 14 years.  Although I had confidence enough in the concept to invest in self-publishing a book on putting it into practice, over this time I have endured increasing cognitive dissonance because the currently popular concept of paleo diet—animal-based, relatively high in protein and fat and relatively low in carbohydrate—conflicts with empirical nutrition knowledge accumulated over the course of 5 thousand years in both Asian and Western medicine, including a rather large body of clinical and laboratory data accumulated since the 19th century, all pointing toward humans being more adapted to a plant-dominated, high-carbohydrate diet supplying significantly less than 30% of energy from fat. 


In addition, over this time period I have experienced myself, and seen in others, mostly gradual and sometimes sudden development of disorders that seem to occur regularly in people attempting to consume a high fat, excessive protein diet.   I have made this connection because of my previous nutrition and health history combined with my formal training in both Western nutrition and Oriental medicine.  To summarize, these unwanted changes have occurred:

1)  General dry skin, and return of inflamed skin lesions in locations previously healed during my years eating a low-fat, plant-based diet, plus emergence of lesions in new locations.  When I restrict total dietary fat to no more than 20% of energy and avoid red meat and  saturated fats, I watch my skin heal, and conversely, when I eat more fat, saturated fats, poultry, and red meat I watch it worsen.  By elimination and reintroduction, I have found that eating 6-8 ounces of grass-finished beef will within 24 hours noticeably increase skin itching.

[Update 3/20/12:  For references, see my post on arachidonic acid provided by all types of meat, discussing the evidence that excess dietary AA promotes inflammation including skin inflammation found in typical skin disorders like eczema and psoriasis, here.  Also my post discussing the evidence that heme iron found only in meat promotes inflammation, here.]

In general, it is standard practice in Chinese medicine to recommend elimination of red meat and poultry from the diet of people with inflammatory skin conditions because long empirical experience as well as Chinese theory indicate that these foods create inflammation (we say that they create heat).  Despite my training in both Chinese medicine and Western nutrition, I tested the paleo hypothesis that these problems are caused by grains.  My experience confirms the Chinese medical view that inflammatory skin conditions arise, not from eating benign gluten-free grains and starches, but from general blood inflammation, toxicity, and stagnation, promoted by heating, congesting, i.e. inflammatory foods such as meat and fats rich in arachidonic acid (for references see here). 

[Update 4/8/15:  In May of 2014 I published on our Plant Based Solution YT channel the following video showing a reversal of an inflammatory skin issue that I developed during my paleo daze, but forgot to add it to this post. ]



From a Western nutrition perspective, excess dietary protein loads the blood with unnecessary acid, ammonia, and urea, and increased dietary fat causes increased coagulability of the blood, which reduces the rate of blood flow, particularly through the fine capillaries, impairing delivery of nutrients and oxygen to and removal of wastes from the skin cells as well as reducing the rate of blood filtration by the liver and kidneys; resulting in chronic low level toxemia.  (3/20/12 Update: For references documenting the effects of fats on blood coagulation and flow, see this , and this.)

2) Gradual return of disabling seasonal allergies and sinus congestion and inflammation, along with chronic congestion of ear canals.  Reduction of dietary fat and protein quickly reduced the symptoms and thinned the secretions.  Prolonged high fat and protein intake appears to increase the thickness and hence stickiness of mucous in the respiratory tract, trapping dust, pollen, and other irritants that stimulate immune and inflammatory responses.

3)  Intermittent bouts of severe abdominal distress clearly caused by high fat intake, from which I could get relief only by fasting followed by reduced fat intake for several days.

4) Irregular bowel movement and, when eating very low fiber, constipation with small, dry, difficult to eliminate stools.  Tracy had the most problem with this.  High fat intake slows intestinal peristalsis, reducing the reliability and frequency of elimination.  (By the way, I have eaten 1.5 to 2.0 pounds of fruits and vegetables daily, providing 50 to 100 grams of fiber,  most of the time I have eaten 'paleo,' which I reported in detail in my book, The Garden of Eating.  Tracy ate similar or greater volumes of plants, so her severe irregularity was NOT caused by too little fiber.  Tracy only got relief by cutting the fat.)

[Update 3/20/12:  I neglected to provide the reference:  Whitney and Rolfes, Understanding Nutrition, 10th Edition, p. 91:  "When fat is present, intestinal motility slows to allow time for its digestion."]

5) [Update 3/20/12] Small yellowish lipomas, also called xanthomas, which have arisen twice during the 14 year paleo stint. Xanthomas occur particularly in people with high blood lipids, which I had for years while eating paleo (total cholesterol of well over 200).
Xanthoma:  Source: Medline Plus.
 The first time they appeared, I eliminated them by eating a very low fat grain-based diet for one period of about 6 months, then returned to eating a 40-60% fat diet rich in red meat.  After another five years or so they returned again.  Xanthomas include xanthelasmas, an accumulation of cholesterol under the skin of the eyelids.  Oriental medicine considers these xanthomas external signs of internal lipid accumulation (e.g. in the arteries), and research confirms that xanthelasmas are indicative of increased risk of cardiovascular disease.  

Xanthelasmas.  Source: TheHeart.org
6) Increasing muscular stiffness in mornings after sleep, along with severe cramps in lower legs occurring regularly at night, especially with very low carbohydrate intake.  The chronic morning stiffness quickly markedly reduced (about 3-4 weeks) after adopting a low fat intake.  I attribute the stiffness to sluggish blood circulation due to increased blood coagulability impairing nutrient and oxygen delivery and waste removal from tissues at night. 

7) Anxiety attacks, which I never experienced before, when eating low (20-25% energy) carbohydrate and high (50-60%) fat.  The attacks occurred consistently after large fatty meals. I attribute this to poor circulation to the brain along with neurotransmitter imbalance caused by inadequate intake of dietary carbohydrate.[Update 3/21/12:  This study found that people on a low carbohydrate diet for 52 weeks scored higher on scales of anger-hostility, confusion-bewilderment, and depression-dejection than people on a low fat diet for the same length of time.]

8) Chronic tension in the shoulders and neck, which decreases when eating less fat and more carbohydrate.  Oriental medicine explains this as an effect of excess dietary fat on liver and gallbladder functions, affecting the circulation in the gallbladder channel which traverses the neck and shoulders.

[Update 3/20/12:  I guess I should have documented that excess dietary fat can impair liver and gallbladder function.  Try searching PubMed with "high fat diet and NAFLD" or "high fat diet and NASH"and you will find plenty of evidence that high fat diets can induce fatty liver disease, like this, and this, or this, and fatty liver disease promotes gallbladder disease

I will give more details about my more than 30 years search for health through nutrition and natural medicine in another blog.

My wife Tracy, who now blogs at The Food Way, had the following distressing developments over the course of just 12 months eating in a low- to moderate-carbohydrate, grain-free paleo/primal fashion:

1) Progressive gain of body fat, due to a positive fat/calorie balance.  Simply, it was easy for her to overconsume calories when eating high fat foods. 

2) Headaches and tension that increased in intensity over the 12 months.

3)  Increasingly persistent right hypochondrial discomfort (discomfort under the ribs), a clinical indicator of stress to the liver.

4) Constipation of increasing severity over the course of the 12 months, due to dietary fat impairing intestinal peristalsis. (Reference given above.)

5) General and increasing sense of fatigue and morning sluggishness with increasing craving for morning coffee, an effect predictable from Chinese yin-yang theory applied to food.  Briefly, a high-fat diet contributes to congestion and stagnation, and coffee's bitter constituents break up the congestion and drain out the stagnation, so people eating high fat diets can find the effects of coffee very attractive or even essential to get things opened up and moving. 

6) Gradually increasing premenstrual breast tenderness and fibrocystic changes.  This was the most alarming symptom to me, because it indicates increasing endocrine imbalance and is unacceptable within Chinese medical gynecology, which recognizes it as an early warning sign for potential breast tumors.

[Update 3/20/12:  This study showed that women with cystic breast disease and breast pain have abnormally elevated levels of prolactin when on a high fat diet, but when they switch to a low (20%) fat diet this abnormality disappears.]

7)  Persistent muscular and joint aches and pains, due to impaired blood flow.

8)  Increasing vasomotor disturbances resulting in hot flashes and night sweats, another sign of endocrine imbalance.  This disorder is also unacceptable to Chinese gynecology and Western scientific research has found that the occurrence of vasomotor disturbance in perimenopausal women is related to fat content of the diet, with high fat diets promoting and low fat diets reducing the occurrence.

9)  Towards the end of the 12 months, she developed regular bloating after our high fat, meat-based meals, a sign of growing fat intolerance.

Since greatly reducing the fat and protein content of her diet, Tracy has had significant amelioration of all of the above symptoms.  You can read more of her account on her blog, The Food Way.

As a result of these experiences I have abandoned meat-based “paleo” dieting as popularly conceived, and realized that all my difficulties were predicted by Chinese medical nutrition theory, which has a few thousand years head start on recent "paleo" diet theory.  I have returned to eating a whole food, high-starch, gluten-free, low-fat (≤20% energy as fat) plant-based diet with much smaller amounts of animal products, primarily fish and shellfish.   Although this accords with both traditional Chinese medical knowledge and modern Western nutrition research, it does not fit with the claim that “paleo diet” consists of a meat-dominated, low-to-moderate carbohydrate, grain-free diet.

[Update 3/20/12:  So many people attack me for my supposedly stupid belief that a paleo diet is meat-based and low in carbohydrates.  I don't get it.  Loren Cordain has gone to great pains to provide evidence that both recent hunter-gatherer and ancient paleolithic era diets were low in carbohydrates.  His books and those of Art DeVany and Robb Wolf all present paleo diet as reduced carbohydrate diets with limited starches.

The folks at the Journal of Evolution and Health recently got all excited by this 2011 paper by Ben-Dor et al which argues that man is an evolved fat hunter and includes the following claims

"modern hunter-gatherer (HG) groups, despite having access to fire and metal tools, also seem to have a strong preference for carnivorous foods over vegetal foods ([53]:682), a notion also supported by a recent study [75] that emphasizes limited consumption of carbohydrates by present day HG groups."
 
"an analysis of nine HG groups for which detailed dietary information exists ([76]:166) shows that five groups, located in an area abundant in vegetation, consumed only a meager amount of plant foods (17% of calories on average)."  

I see no indication that scientists promoting paleo diet are endorsing high carb, low fat, low meat diets.  I don't base my idea of paleo diet on what bloggers write, I base it on what the advocates of it have written in peer-reviewed science journals.]

Although I now believe that reverse engineering from presently observable human biochemistry and physiology suggests that modern humans are adapted to a high-carbohydrate, low-fat diet with relatively low or intermittent intake of animal foods (by current Western and especially "paleo diet" standards), mostly of fish and shellfish,  I doubt that my input will change the now entrenched idea that human evolutionary “paleo” diets were meat- and fat- rich and plant-food poor.   Therefore, I will not even attempt to call what I do or advocate a “paleo” or “primal” diet, although I think it appropriate to do so.  

But for now I won’t be changing the name of my blog. From the beginning I defined “Primal Wisdom” as the innate intelligence of the bodymind, written in its various nutritional and other requirements, as well as in all the movements of Nature, which inform the Chinese scientific principle of yin-yang complementary opposition.  Apparently the Nobel Prize winning physicist Niels Bohr understood the importance of this scientific principle, since he chose the yin-yang symbol for the his coat of arms. 
Coat-of-arms of Niels Bohr.  Source: Wikipedia

In future posts,  I think I will further discuss how we apply this and other Chinese medical principles to nutrition in such a way that makes sense out of the confusing mass of nutrition information available both within scientific research and in practical experience. 

 Hence, my farewell to popularized paleo.   I hope all “paleo,” “primal,” and “hunter-gatherer” dieters fare well in their quest for health.    So long as what you do continues to work for you, keep doing it.  I hope that you have the knowledge, clarity of mind, and subtlety of awareness to notice the early signs of malfunction before you succumb to something serious and beyond repair.  I have a series of blogs forthcoming on this topic, outlining the Oriental medical understanding of the progression of disease from minor to major, which Chinese physicians have used for millenia to help people reverse and prevent diet-related diseases.