“People are convinced that fruit and vegetables are a particularly good source of vitamins and minerals.
“For a long time, I too was a believer. I was a vegetarian for 20 years. It is only after nearly two decades of my own research — I am a Cambridge graduate and currently studying for a PhD in nutrition —that I have changed my views.”
Nice stab at an appeal to your own authority. It does not matter to me whether you graduated from Cambridge or taught yourself, and I don’t care about PhDs either, only care whether you use facts and logic properly. I was also a vegetarian for many years, no longer, but being a vegetarian doesn’t make you knowledgable about nutrition or vegetables either.
“The message that fruit and veg are pretty useless, nutritionally, gradually dawned on me.”
Zoe, you can’t rationally talk about the nutritional content of fruits and vegetables generically, because they—particularly vegetables—vary too much in nutrient content. Its like saying that motorized vehicles are “pretty useless” for traveling to the moon—which motorized vehicles are you talking about? There's a vast difference in nutrient density between zucchini and collards. Think, Zoe, think.
“The facts are these. There are 13 vitamins and fruit is good for one of them, vitamin C.
“Vegetables offer some vitamins — vitamin C and the vegetable form of the fat-soluble vitamins A and vitamin K1 — but your body will be able to absorb these only if you add some fat, such as butter or olive oil.
“The useful forms of A and K — retinol and K2 respectively — are found only in animal foods. As for minerals, there are 16 and fruit is good for one of them, potassium, which is not a substance we are often short of, as it is found in water.”
Whoa….hold on Zoe. The you just said that fruit is "pretty useless," then you say it is good for vitamin C. You can’t have it both ways, both useless and useful. Then, the fact that you need to have some fat with vegetables to absorb carotenoids and K1 does not make vegetables useless. This is like saying that autos are useless because you have to fill them with gasoline to make them work. Perhaps you forgot that you also have to consume fat with retinol and K2 as well, putting them in that respect on par with K1 and carotenoids.
Next, you state that carotenes and vitamin K2 are the useful form of the A and the K complex, implying that K1 is not useful, which is simply wrong. We need K1 for normal blood clotting function. Moreover, it appears that vitamin K1 can protect arterial elasticity . As for carotenes, perhaps you consider them useless, but I don’t feel so certain, since humans accumulate carotenes in various tissues, they appear associated across species with longevity, we have evidence that they provide photoprotection, and may have roles in fertility and breast health.
“Vegetables can be OK for iron and calcium but the vitamins and minerals in animal foods (meat, fish, eggs and dairy products) beat those in fruit and vegetables hands down. There is far more vitamin A in liver than in an apple, for instance.”
Again you contradict yourself, after saying vegetables are “pretty useless, nutritionally” you admit that they contain iron and calcium. Then you set up a straw man argument by comparing apples, which contain no vitamin A, to liver, which does contain vitamin A. Since you assert that meat, fish, eggs, and dairy products beat “fruit and vegetables hands down,” let’s compare collards and beef sirloin on a gram for gram basis, first for vitamins:
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• Collards excel in folate (10:1), vitamin C, provitamin A (as carotenoids) , vitamin K1 (400:1), and vitamin E (almost 2:1).
• Beef excels in B1 (1.5:1), B2 (1.2:1), B3 (12:1), B5 (2.4:1), choline (~3:1), B6 (~4:1), and B12.
• Of 12 vitamins, collards excels in 5, beef sirloin in 7.
• Where collards excel, they do so by greater margins than by where sirloin excels.
Consider that the beef supplies nearly 10 times the caloric value of the collards, which means the nutrient density of collards relative to caloric content far exceeds that of beef. Thus, looking at vitamins, I find it hard to dismiss “vegetables” as nutritionally useless. Collards provide far more folate, vitamin C, K1, and E than beef, as well as carotenoids which may or may not have vitamin A value depending on the genetic constitution of the consumer, but which in any case may have functions in photoprotection and fertility. Although we absorb only about 10% of K1 in vegetables if consumed with fat, discounting the K1 in collards by 90% they still deliver amost 30 times more K1 than beef sirloin.
Now for minerals:
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• Collards excel in calcium (8:1) and manganese (44:1).
• Beef clearly excels in iron (1.5:1), phosphorus (almost 7:1), potassium (about 2:1), zinc (20:1), copper (>2:1), and selenium (60:1).
• The value for magnesium is not significantly different (beef:collards = 1.1:1)
Thus, collards equal or exceed beef sirloin as a source of calcium, magnesium, and manganese, while beef provides more iron, etc. Again, I don’t see how one can say that “vegetables” are nutritionally useless compared to animal products until you specify which vegetables and which animal products you want to compare.
If you compare kale and beef sirloin on a calorie for calorie basis, you find something even more remarkable:
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So kcalorie for kcalorie kale provides:
• 93 times more calcium
• twice as much iron
• 3.75 times as much magnesium
• five times as much potassium,
• 2486 more units of provitamin A activity (mostly in humans not forming A, but used as carotenoids)
• 2.4 times as much thiamin
• 44 times as much vitamin E
• almost ten times as much folate
• and 86 mg more vitamin C.
If that makes kale nutritionally useless, I don’t know what would make it useful.
If I compared these greens to eggs, milk, liver, or any other animal product, the results would be different. I'm not claiming that vegetables are superior to animal products, only argue against the headline grabbing claim that vegetables are "pretty useless."
Comparing apples to liver for vitamin A content makes you, Zoe, look like the inverse of the vegetarians who attack animal products for not supplying fiber and carbohydrates. Apples aren't useless because they don't provide retinol, and liver isn't useless because it doesn't have fiber or much vitamin C. Jets aren't useless because you can't drive them on highways, and cars aren't useless because they don't fly.
“But surely, people ask, even if there is no evidence that increasing our intake of fruit and vegetables will help prevent disease, they remain good things to eat?
“I don’t think so. If people try to add five portions of fruit and veg — let alone eight — a day to their diet, it can be counterproductive. Fruit contains high levels of fructose, or fruit sugar.
“Among dieticians, fructose is known as ‘the fattening carbohydrate’. It is not metabolised by the body in the same way as glucose, which enters the bloodstream and has a chance to be used for energy before it heads to the liver.
“Fructose goes straight to the liver and is stored as fat. Very few people understand or want to believe this biochemical fact.”
Here’s another straw man. One can easily eat 5 portions of vegetables daily (2.5 cups cooked) and avoid your dreaded fructose. Further, the statement “Fructose goes straight to the liver and is stored as fat” is out of context, namely the context of energy expenditure. It will only be stored as fat if that fat is not needed for use as energy.
“Another argument that is often put forward by dieticians on behalf of fruit and vegetables is that they are ‘a source of antioxidants’.”
Funny, just above you are quoting dieticians as the supreme source of knowledge on the metabolism of fructose, but now you put them downs as stupid for believing in plant foods as sources of antioxidants.
Tell us more:
“The biggest tragedy of all is the lost opportunity from this misguided five-a-day campaign.
“If only we had hand-picked the five foodstuffs that are actually most nutritious and spent what the Department of Health has spent on promoting fruit and vegetables over the past 20 years on recommending them, we could have made an enormous difference to the health and weight of our nation.
“If you ask me, these foodstuffs are liver (good for all vitamins and packed with minerals), sardines (for vitamin D and calcium), eggs (all-round super-food with vitamins A, B, D, E and K, iron, zinc, calcium and more), sunflower seeds (magnesium, vitamin E and zinc) and dark-green vegetables such as broccoli or spinach (for vitamins C, K and iron).”
WHAT? Zoe, you started this article telling us that vegetables aren’t good sources of vitamins or minerals, and said that K1 in vegetables is useless, and then you even implied that they aren't even "good to eat," but now you tell us we should eat dark-green vegetables of vitamins C, K(1), and iron? Give me a break. You clearly attacked “vegetables” just to grab a headline.
You haven't given me a very good impression of Cambridge graduates or whatever PhD (piled high and dry?) program you're completing. Try again Zoe.
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