Part 2 of my multipart series on herbals and supplements. This one is on Vitamins.
I remember early in my career seeing a huge study that had 40,000 patients and went over decades to see if herbals and supplements helped or hurt people. The finding of that study was only Calcium and D were worthwhile. I just did another search to see if there is updated stats, and I found a good summary in the Journal of Epidemiology which looked at many prior studies and did a prospective, multi ethnic large study. The result? Vitamins and minerals had no effect on cancer risk, heart risk, or mortality. See the study HERE.
While researching, I saw a lot of information about Vitamin D. Make sure your levels are normal, and there is growing evidence it may help with prevention and health in many areas- MS, cancer, Covid. To see the studies out there click HERE. Again Vitamin D may be an outlier, where supplementing it actually does something, though it is only recommended to get you into the normal range (what “normal” or a “good” number is up to debate still.)
So if vitamins are not shown to do a lot of good, you need to make sure they aren’t going to hurt you. What is the downside?
- Water soluble vitamins toxicity is rare, as you are peeing out the excess.
- B6 Pyridoxine: doses higher than 500 mg/d can cause sensory nerve issues
- Vitamin E Tocopherols. 800-1200 mg/d can cause bleeding due to antiplatelet action; doses 1200mg and higher can caues diarrhea, weakness, blurry vision, and gonad issues. One study looking at cancer patietns found an increased cancer recurrence rate in patients due to high dose Vitamin E supplements
- Vitamin A Retinol Beta carotene. May worsen bone mineral density (increased fracture risk!) and congenital abnormalities if you take while pregnant. Two studies showed increased cancer: one was male smokers who had higher rates of lung cancer, another showed male drinkers had higher prostate cancer rates.
- Iron. An iron storage disease causing liver injury if excess iron or multimineral supplements. This is worsened by alcohol (which is also processed by the liver)
My thoughts?
Many of these studies talk about how we are getting most macro and micronutrients in our diet. If you had weight loss surgery, you may need supplements. If you are allergic to dairy, you made need calcium. Many of us have Vitamin D deficiency.
The thing to remember here is more does not equal better. And look for hidden sources- many fish oil and omega 3 supplements ALSO have Vitamin A. As may your multivitamin.
Vitamin E- along with fish oil, omega, flax seed, and collagen- are known to increase bleeding issues in surgery, so I have my patients stop before. I know I cannot give Retinol or Retin A to anyone who is pregnant or nursing.