Milk thistle. Acidophilus pearls. Their ingredients can often sound like so much hocus-pocus, but that hasn’t dampened our love of dietary supplements. More than 150 million of us, in fact, take them.
Yet, less than two decades ago, experts believed a modern diet provided all the nutrients anyone would need. Unless you had scurvy or weak bones, the argument ran, supplements were nothing more than a prescription for vitamin-rich urine.
Today, it’s a bit more complicated than that, thanks to more diverse research data and a growing segment of the population obsessed with living healthier, longer lives. And while some of what we hoped vitamins would do has proven true, it seems we’re not out of the proverbial rabbit hole just yet.
A recent Nielsen poll covering 52 countries showed that only four out of 10 consumers worldwide take supplements. U.S. respondents tended to use supplements for boosting their immune and metabolic systems, improving memory, and slowing age-related macular degeneration and chronic inflammation.
But while our country had the highest number of daily users, only a small percentage used supplements per doctor’s orders. Many cited longer life expectancy benefits but didn’t know which supplements they should be taking.
Doctors typically recommend a daily multivitamin tablet only if you’re AARP eligible. Even so, it’s understandable that our increased use of supplements has paralleled developments in research on the aging process. Scientists now know that certain antioxidant molecules are intimately involved in preventing cellular damage—the common pathway for cancer and many diseases.
Thanks to the establishment of the National Institutes of Health’s Office of Dietary Supplements in the mid-1990s, there is now a trusted resource for consumers and the medical community. Still, much like nutrition in general, our understanding of supplements is often based on our awareness of dietary needs. So it’s a safe bet that, if you’re healthy, you’re not thinking about the body’s anti-inflammatory process nor its connection with zinc and fish oil.
Ten years ago, supplements were a popular choice for controlling or lessening chronic swelling. Now, we’ve paired that practical knowledge with a more thorough understanding of how inflammation works to heal the body—and how, over time, the condition may be an underlying cause of cancer, rheumatoid arthritis and neurological degenerative diseases like Parkinson’s.
Sound too good to be true? Well, there is a catch: Scientists have yet to determine the correlation between dosage and disease prevention. In recent years, the Institute of Medicine raised the recommended daily intake of vitamins C and E when long-term studies showed reductions in vascular dementia, the second most common form of dementia (after Alzheimer’s) among seniors.
So while supplements may be aptly named, they’re complex in their effects. And though they’re not substitutes for the real thing, those who don’t regularly consume fish, for instance, are often advised to take fish oil supplements.
Still, supplements shouldn’t be used to treat, mitigate or prevent disease—even if several are considered crucial in deterring serious age-related illnesses. The list includes antioxidants, Omega-3 fatty acids (fish oils), ALC (acetyl-L-carnitine and alpha-lipoic acid), B vitamins (so-called stress vitamins), selenium, calcium, magnesium and iron.
Supplements are not without side effects and overdose risk. Those that are fat soluble (stored in the liver and fatty tissues) can’t be easily eliminated and pose greater threat for toxicity. “There are many potential interactions that people should be aware of,” says Christine Hurley,
a registered dietician with Main Line Health’s diabetes and nutrition management centers.
Hurley cites vitamin D–or a lack thereof—as particularly problematic. Fortified foods are readily available, and yet deficiencies are all too common these days, especially among older Americans. Some experts call it a silent epidemic.
Vitamin D is the only essential nutrient dependent on outside factors. Sunshine or ultraviolet light produces it from cholesterol. Improved sunscreens act as a barrier, and older skin can’t readily absorb the vitamin. “Most people are unaware of the importance of vitamin D,” says Hurley. “It affects 37 tissues in the body. In fact, I make it a point that every child or adult have their blood work done [for vitamin D] if I don’t see on their lab work.”
Antioxidants are among the most popular choices when it comes to age-related issues. Supplements that target our inner workings, however, also tend to be fat soluble, making them the most likely to fall into the “more isn’t always better” category. They can produce harmful effects if taken in large doses, or with blood thinners and cholesterol-reducing drugs like Lipitor.
Three vitamins act as antioxidants in the body and are essential to many of its cellular functions: vitamins C and E, and beta-carotene (provitamin A). They work to target molecules known as free radicals—which, if you follow the latest fitness and sports trends, seem to be synonymous with anything bad happening in the body. In reality, free radicals are normal parts of life—created as we live and breath, and when oxygen is broken down during metabolism.
Among athletes, there’s a tendency to take megadoses of antioxidants. Exercise requires increased oxygen production, setting off the production of free radicals—a process known as oxidative stress. The theory is that repeated strenuous activity leads to more damage. It’s prompted the widespread—some say misguided—belief that food alone can’t maintain sufficient levels of antioxidants in the body.
Typical of many experts in the medical community, Hurley is cautious of fully endorsing such supplements. After all, it’s only been in recent years that oxidative stress has been linked to aging, diseases like Alzheimer’s, and heart attack and stroke risk. But, as we age, free radicals can indeed become reactive and willful, prone to overproduction in a way that damages tissues and cells.
Keeping free radicals in check is one of today’s prevailing medical mysteries, but scientists are not deterred. Two of the largest long-term studies to date focused on how supplements enhance the body’s free radical defense system. Unfortunately, neither proved a ringing endorsement. One found no significant drop in cancer mortality rates among women taking vitamins C, E and beta-carotene. The other contradicted earlier results supporting decreased risk for cardiovascular disease in men taking those same supplements.
Meanwhile, a recent NIH study showed that women taking vitamin E experienced a 24-percent reduction in total cardiovascular disease mortality. And research involving male athletes taking moderately high doses of vitamins C and E found no advantages to doing so. In fact, the increased levels of those vitamins appeared to overload the body’s finely tuned insulin-exercise response.
So, clearly, gauging the overall health effects of supplements continues to be difficult. That in mind, Hurley prefers to promote only nature’s antioxidants—blueberries, carrots, green tea. She’d rather tout the benefits of healthy eating than promote anything that might interfere with our natural antioxidant defenses.
“It’s the position of the American Dietetic Association to promote healthy eating,” says Hurley. “The hope is that people will choose from a wide variety of nutrient-rich foods to reduce their risk of disease.”
Still, even Hurley admits that she does something for “added insurance.” She takes a multivitamin.
To learn more, visit ods.od.nih.gov.
Vitamin A and Carotenoids: May slow the progression of age-related macular degeneration.
Vitamin B: Helps lower homocysteine levels, and reduces heart disease and stroke risk.
Vitamin C: May protect against cataracts.
Vitamin D: Keeps bones healthy by boosting mineral density; believed to lower risk of cancer, heart disease and infection.
Vitamin E: Assists in the body’s anti-inflammatory process; may prevent or delay the onset of age-related macular degeneration and cognitive decline.
Vitamin K: Assists in clotting and the modification of certain blood proteins; bone-strengthening properties make it ideal for postmenopausal women, and male and female athletes.
Folic Acid: Reduces heart disease, stroke and colon cancer risk; lowers homocysteine levels, a known link to Alzheimer’s.
Source: National Institutes of Health’s Office of Dietary Supplements
1. Vitamin supplements do not prolong life.
2. Supplements are complex products—either water soluble or fat soluble.
3. It’s estimated that one in three people is vitamin D deficient.
4. Supplements can be harmful if not taken in recommended doses.
5. Vitamin supplements can interact with certain prescriptions, as well as with other vitamins.
6. Most supplements need to be taken on a daily basis.
7. Supplements are not FDA approved.
8. Supplements are no longer confined to tablet form.
9. Supplements are not without risk or side effects.
10. Some supplements are better for women than men—and vice versa.
Source: National Institutes of Health’s Office of Dietary Supplements