Single Supplement Cautions - Can Selenium, Iron and Calcium Cause Disease?

We are often told that our daily vitamin intake is likely to be less than adequate. And broadly, this is very true! However, unless you are a biochemist, the dangers of self-dosing with single supplements (only vitamin C, only selenium, pure iron tablets, etc) are real and can be huge. Simply because they are natural, doesn’t mean they are good for the body in any dose. Today we look at four cautionary research stories on single supplementation, and follow up with your best and safest alternatives … whole food multivitamins.

Iron Linked to Parkinson's Disease

You know all those antioxidants that you try to consume, and even supplement with, day after day? If you are taking more iron than your body can use, you might be whittling away all that oxidation protection from your blueberries and wheat bran. Harvey Checkoway, PhD, of the University of Washington in Seattle conducted a diet survey on several hundred newly diagnosed Parkinson's patients, and found that those whose iron intake is in the top 25% of people were 1.7 times more likely to be Parkinson's patients. If you take iron and manganese single supplements (to put your total intake in the top 25%), you are almost twice as likely to develop Parkinson's, according to the study.

Calcium Linked to Prostate Cancer

Wake Forest University School of Medicine and the University of Wisconsin recently collaborated on an analysis of the 2800 or so men who participated in a nationwide diet study, the National Health and Nutrition Examination Survey. The study authors stated that there was a significantly increased risk of prostate cancer in men in the top third of calcium consumption compared to the bottom third.

Selenium Linked to Diabetes

Taking a single selenium supplement of 200 micrograms daily was shown in a recent study to increase the risk of developing type two diabetes. The Nutritional Prevention of Cancer Trial gave the supplement to over a thousand people, and found that the risk of developing diabetes actually increased when taking a single supplement of this mineral, rather than a whole food multivitamin containing it.

However, this certainly does not contradict earlier scientific studies finding that a well rounded vitamin and mineral intake can help slow aging and prevent disease. It simply means that self-diagnosing and dosing with single supplements may be doing you more harm than good. Whole food multivitamins are specially formulated to deliver a range of vitamins in safe, complementary doses from natural sources. Much harder to overdose on, and much better for you!