
Supplements
Popping a pill is easier than eating an apple, so should we take supplements?
Generally speaking, Mother Nature’s powers cannot be stuffed into a pill. Studies have repeatedly shown that antioxidant supplements, for example, do not seem to have any beneficial effects on respiratory or allergic diseases, underscoring the importance of eating whole foods rather than trying to take isolated components or extracts in pill form. The Harvard Nurses’ Health Study, for example, found that women who obtained high levels of vitamin E from a nut-rich diet appeared to have nearly half the asthma risk of those who didn’t, but those who took vitamin E supplements saw no benefit at all. Who do you think did better? Asthma patients who ate 7 daily servings of fruits and vegetables, or those who ate 3 servings plus 15 “serving equivalents” in pill form? Sure enough, the pills didn’t seem to help at all. Improvements in lung function and asthma control were evident only after subjects increased their actual fruit and vegetable intake, strongly suggesting that consuming whole foods is paramount.
By getting our nutrients from unprocessed plant foods, not only may we minimize exposure to harmful food components, such as sodium, saturated fat, and cholesterol, but we may maximize our intake of nearly every required nutrient: vitamin A carotenoids; vitamin C; vitamin E; the B vitamins, including thiamin, riboflavin, and folate; as well as magnesium, iron, and potassium, not to mention fiber.
However, given our modern lifestyles, important shortfalls need to be corrected. For example, vitamin B12 is not made by plants; it’s made by microbes blanketing the earth. But in this sanitized modern world, we now chlorinate the water supply to kill off any bacteria. While we don’t get much B12 in the water anymore, we don’t get much cholera either—that’s a good thing! Similarly, we evolved to make all the vitamin D we need from the sun, but most of us are no longer running around naked all day in equatorial Africa.
Thus, I recommend a regular, reliable source of vitamin B12 for anyone eating a plant-based diet: for those 65 and younger, 2,000 mcg (μg) vitamin B12 in the form of cyanocobalamin at least once a week (or 50 mcg a day), and up to 1,000 mcg daily if over 65. I also recommend that people unable to get sufficient sun take one 2,000 IU vitamin D3 supplement daily, ideally with the largest meal of the day.
The information on this page has been compiled from Dr. Greger’s research. Sources for each video listed can be found by going to the video’s page and clicking on the Sources Cited tab. References may also be found at the back of his books.
Image Credit: Pat_Hastings / Thinkstock. This image has been modified.
Popular Videos for Supplements


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Are Supplements and Vitamins B12 and D Really Necessary on a Plant-Based Diet?
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Do Vegans Have Lower Bone Density and More Fractures?
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The Best Type of Vitamin B12: Cyanocobalamin or Methylcobalamin?
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