Chapter 41
Dietary Supplements
I knew that antioxidant supplements had grown into a multibillion-dollar business, but I was still surprised to learn that, according to a book about global price-fixing, they had by now turned the pharmaceutical industry into the “largest, most complex, longest-lasting, and most harmful of the international cartels” “discovered by the U.S. Department of Justice in the 1990s.” Before pharmaceutical companies were hit with dozens of criminal convictions and record fines, they had conspired in complex, illegal, monopolistic price-fixing schemes to rake in billions in profits from the inflated prices of vitamin supplements. And even more outrageous, the people who were cheated got nothing for their money—or even worse. No antioxidant supplement has ever been proven to reduce mortality, and supplemental beta-carotene, vitamin E, and higher doses of vitamin A may even have shortened their lives. This is also consistent with many animal studies, in which either no effect at all or a considerable shortening of lifespan was found. There are countless antioxidant supplements on the market, many of which make “highly exaggerated and … erroneous” claims. Here is a brief overview of the less well known ones.
Alpha-lipoic acid
Alpha-lipoic acid is an antioxidant that our body produces on its own. Does it offer any benefit to take it as a dietary supplement as well? In see.nf/lipoic I discuss the pros and cons. The bottom line? I would be cautious with it until we have a better sense of safe dosing.
Coenzyme Q10
Coenzyme Q10 is the only fat-soluble antioxidant produced by the human body. Since we synthesize it from our own resources, there is no need to consume it, and yet it is one of the most popular dietary supplements. Centenarians have lower levels than 76-year-old control patients, but this fact can be used to justify two diametrically opposed positions: Some postulate that Q10 levels decline with age and that we should supplement to regain youthful values; others claim the low level is beneficial for achieving such a remarkable lifespan.
Animal studies reflect this dilemma. In fact, altered Q10—whether increased or decreased (by suppressing its synthesis)—extended lifespan in C. elegans, but had mostly no effect in rats and mice. In humans, Q10 supplementation lowers inflammation markers and oxidative stress and benefits heart failure patients and also migraine patients, who got headaches less often and of shorter duration, but they were just as severe. Anyone who wants to take Q10 has to store it in a cool, dark, airtight container, because it is sensitive to heat, light, and oxidation. I prefer to renew it naturally with the technique I describe in How Not to Die in my chapter on green vegetables. That includes a chlorophyll-rich diet, which is especially important for those taking cholesterol-lowering statins, since these medications can interfere with Q10 production.
Ginseng
Ginseng root is a popular remedy in herbal medicine. The Latin designation for ginseng, Panax, comes from the Greek roots pan and akos for “panacea.” But although more than 100 clinical studies have been conducted on different ginseng preparations, the results were not very convincing even for one of its most promising uses (blood sugar regulation).
With respect to oxidative stress, American (Panax quinquefolius), Chinese (Panax notoginseng), and Korean (Panax ginseng) ginseng were found to protect strongly against DNA damage from free radicals a few hours after consumption, but a long-term study set off alarm bells. Four weeks of taking Korean ginseng did reduce oxidative stress, but then American ginseng was taken for four months, and less than a quarter teaspoon of powder from the whole root increased DNA damage. Until it is proven for other types of ginseng that their long-term use does not trigger DNA damage, I would recommend avoiding it.
N-acetylcysteine
N-acetylcysteine (NAC) extended the lifespan of male mice, but not females, and only because it apparently led to reduced food and water intake. In C. elegans and fruit flies, one dose extended life, but more dramatically shortened it by up to 70 percent, raising “serious concerns” about taking dietary supplements containing NAC. More details in see.nf/nacse.
Selenium
Selenium, an important component of key antioxidant enzymes, is considered an essential trace element. However, given its narrow safety margin, it has also been called an “essential poison.” Just one Brazil nut a day, a nut with a high selenium content, has a pro-inflammatory effect. In see.nf/nacse I also talk about selenium, but in summary, both low and high amounts in the blood have been linked to premature death, and certain amounts of selenium supplements can both shorten your life and worsen blood sugar regulation in diabetics, as well as increase overall diabetes risk.
What about vitamin C?
Vitamin C is probably the most abundant antioxidant in the body, but its levels decline with age. Vitamin C levels in the blood cells of those over 85 may be only half as high as in 60-year-olds. Vitamin C amounts in the brain decrease by about 40 percent (comparing those over 60 with those under 59). Would it help to restore youthful levels? It was tried and did nothing. Vitamin C supplements neither extend life nor improve quality of life or mental performance, and they also do not prevent eye diseases, infections, cardiovascular disease, or cancer.
There is insufficient evidence that vitamin C supplements prevent DNA oxidation at all, and at higher doses (about 900 mg plus NAC) they can even cause more oxidative damage. The double-edged nature of vitamin C has similarly been shown in animal models: an antioxidant at lower doses, but a pro-oxidant at higher ones. That is why animal studies have found that treatments with vitamin C either increase or decrease life expectancy, or do not affect it at all.
High-dose supplementation with vitamin C can lead to oxidative DNA damage, but so can levels below the recommended daily allowance. Over the last 20 years, vitamin C intake in the United States has fallen by more than 20 percent, largely due to decreased consumption of fruit juices, without this having been offset by whole fruit. It has now gone so far that almost half of all Americans fall below the estimated average daily requirement. What is the optimal amount? See see.nf/vitaminc for details, but the magic number appears to be about 200 milligrams daily. Since a single serving of fruits and vegetables contains about 50 grams of vitamin C, four or five servings of fruits and vegetables daily should get you to ideal blood levels.
Another reason to avoid megadoses of vitamin C is the risk of kidney stones, at least in men. Those taking around 1000 milligrams of vitamin C per day could double their kidney stone risk, from a probability of 1 in 600 to 1 in 300. Whether women are equally at risk, we do not yet know.
Food for thought
The mitochondrial theory of aging explains why animals that produce the fewest free radicals live the longest. We can slow this pace through exercise and methionine restriction, namely through a predominantly whole-food, plant-based diet. With such a dietary pattern, pro-oxidant foods that are high in cholesterol, salt, saturated fat, and sugar would also be limited; instead, one would increase consumption of plant foods that have the dual benefit of strengthening our primary oxidative defense via activation of Nrf2 as well as the second line of resistance against radicals—the symphony of natural antioxidant components that can work in concert, as antioxidant supplements demonstrably cannot.
To slow this pathway of aging, you should daily:
Sirtuins
We all carry dozens of billions of miles of DNA within us—if you were to unwind the strands and join the ends together, it would add up to a distance sufficient for 100 000 flights to the moon and back. How does our body manage to keep these precious chains of information from getting hopelessly tangled up with one another? Enzymes called sirtuins ensure that our DNA stays neatly wrapped around spiral-like proteins, thereby silencing the genes on that segment of DNA. The name SIRtuin stands for Silencing Information Regulator (“regulator for the silencing of information”).