Sunday, August 25, 2013

Nutritional Update for Physicians: Plant-Based Diets

Nutritional Update for Physicians: Plant-Based Diets

This article contains a pretty good discussion of the differences between a whole foods plant-based diet (health-promoting) and vegan or vegetarian diets (not necessarily health-promoting).   The whole foods plant-based diet is defined by what it includes (whole plant foods, emphasizing vegetables, fruits, nuts, and seeds, plus B12 and sun exposure), whereas vegan diets are defined by what they exclude (animal products) with no restrictions on what they include within the plant realm and no specific attention to nutritional adequacy.  Thus a vegan diet can include refined oils, hydrogenated oils, large amounts of saturated fats (tropical), refined carbohydrates, and so on, and the vegan does not necessarily eat recommended levels of fruits, vegetables, nuts, or seeds, get sun exposure, take vitamin B12, have a reasonable essential fatty acid balance, or pay any attention to getting adequate intakes of energy or other essential nutrients.  The incorrect conflation of these two can lead one to confuse their health effects. 

While many vegans do eat whole foods plant-based diets to some extent, not all do, and the inclusion of the latter in data sets defined by exclusion (no animal products) can confound results of research.  Keeping this in mind, it remains remarkable that, as reviewed in this article, a significant number of studies have provided evidence that people eating vegan or plant-based diets have significantly reduced risks of obesity, diabetes, cardiovascular disease, hypertension, and overall mortality.

The article also leads off with a case study of an individual prescribed a plant-based diet, with a report of the positive health effects.

Saturday, August 24, 2013

Elephants Display Musical Appreciation and Talent

Awesome. The herbivorous elephant has one of the largest brains on the planet, built entirely from nutrients found in plant foods. I have never seen any dogs, cats, or other carnivores playing musical instruments or responding to music the way these wild herbivores do.

The elephant has a 4.2 kg brain, about 3 times as large as humans or dolphins, and a cortical neuron count of 11,000 million, about the same as humans, and twice that of dolphins or chimps.  They build and maintain their brains without regularly consuming seafood, marrow, muscles, or brains of other animals, as do millions of humans around the globe who adhere to plant-based diets for philosophical or cultural reasons:  Seventh Day Adventists, Buddhists, Jains, Taoists, and Hindus [1].  

"Millions of individuals around the modern world, including some 2.5% of Americans and 4% of Canadians (American Dietetic Association and Dieticians of Canada, 2003), consume a diet classified as vegan or vegetarian. There are also a number of religious doctrines that emphasize abstention from animal consumption, including Jainism, Buddhism, Hinduism, and Taoism, involving a significant percentage of modern human populations. In the case of these vegetarians, many have maintained such a restricted diet for generations. Neurological impairment under generational deficiency of DHA should result if dietary DHA is essential for neural function. Given that these populations experience normal brain growth and development in the absence of dietary DHA, it seems reasonable to question the nature of our dietary requirements for n-3 fatty acids. If preformed DHA is essential, and only significantly available from aquatic dietary sources, the expected outcome of a vegetarian lifestyle is the failure of neural growth and development. On the other hand, there is no evidence to suggest that the capacity for DHA synthesis in vegetarians is limited (Sanders, 1999). A logical explanation involves the sufficiency of LNA from the dietary intake of plants to provide sufficient DHA for the neural development of these populations."[1]

Here's part 1 of a longer documentary on the Thai elephant orchestra led by two scientists: