If you read clinical trial results carefully, then you will find a pattern in the results for vitamins.
When a vitamin deficiency is corrected to normal levels, miraculous things happen. Patients live years longer than those on placebo. Chronic wounds finally heal, vision is preserved, energy levels are restored, and stamina goes up.
Oftentimes, a deficiency is corrected with vitamin doses that are larger than what the FDA recommends, in order to prevent another deficiency from occurring later. But when a normal vitamin level is elevated even higher, then good things no longer happen, and bad things may transpire.
These findings are usually unexpected. For instance, one study elevated normal levels of B vitamins even higher in an attempt to lower homocysteine levels in diabetics with poor renal function.
Because B vitamins are water-soluble, it is believed that the body just washes out the excess and no damage will occur. Since homocysteine is a marker of bad health, the study authors theorized that artificially lowering homocysteine levels with B vitamin supplementation would improve kidney function and help the subjects become healthier.
But that is not what the study yielded. Surprisingly, the renal function actually got worse.
Similar studies conducted with the hopes of improving cardiac function through B vitamin supplementation in patients with high homocysteine saw worsening cardiac function. This pattern was also perceived with fat-soluble vitamin A.
Patients with naturally high levels of vitamin A have a very low risk of lung cancer, so the thought behind one study was to give those at risk of lung cancer vitamin A pills and see whether their lung cancer rates would decline.
Surprisingly, the lung cancer rates went up significantly, and the study was stopped prematurely to prevent unnecessary deaths.
The pattern repeats itself with iron. If deficient iron levels are restored to normal, then patients’ energy and stamina increase significantly, but elevating normal levels even higher is lethal. Hospitals use chelating agents to reverse iron overdoses and prevent death.
So, what does the FDA say about vitamins? According to its website and easy-to-understand video for the public: “For some vitamins and minerals, the National Academy of Sciences has established upper limits of intake that it recommends not be exceeded during any given day. Do not exceed the safe upper limit dose on vitamins.”
It seems that the FDA has come to the conclusion that most things in nature require a happy medium or healthy range. Like water, air, sun, food, and exercise, too much or too little is not healthy.
The FDA also tells patients to get vitamins from whole foods, consult their health care provider about taking vitamins, and avoid taking vitamins to prevent a deficiency.
In light of the studies I referenced, I’d have to agree with all of the FDA’s advice.
Getting vitamins from whole foods has never been associated with negative health effects in healthy individuals without a defect in their biochemistry. Having naturally high levels of vitamins in your bloodstream is a marker of good health, and longevity predictors always use the consumption of fruits and vegetables to predict how long someone will live.
Consulting a health care provider about taking vitamins is also very sound advice since he or she can discover a vitamin deficiency that needs to be corrected before miraculous health benefits can potentially occur. Correcting a vitamin deficiency will also require a higher dose than is listed in any reference range, and will probably require a judgment call based on the severity of the deficiency.
I commend the FDA for giving patients excellent advice regarding vitamins and minerals, but I recommend that the FDA provides the rationale behind its advice to ensure better patient compliance.
The author has no affiliation with the FDA.
- House AA, Eliasziw M, Cattran DC, Churchill DN, Oliver MJ, Fine A, Dresser GK, Spence JD. Effect of B-vitamin therapy on progression of diabetic nephropathy: a randomized controlled trial. JAMA. 2010 Apr 28;303(16):1603-9. DOI: 10.1001/jama.2010.490.
- Omenn GS, Goodman GE, Thornquist MD, Balmes J, Cullen MR, Glass A, Keogh JP, Meyskens FL, Valanis B, Williams JH, Barnhart S, Hammar S. Effects of a combination of beta-carotene and vitamin A on lung cancer and cardiovascular disease. N Engl J Med. 1996 May 2;334(18):1150.