Why do dietitians not recommend vitamin / mineral supplements except those not getting the RDA?


I am an exercise physiologist and weight management, consultant. I enjoy your website and your comments, but I wanted to get your take on why the industry standard for dietitians is to not recommend vitamin/mineral supplements except for those who are not getting “The RDA”.

I don’t really know how you feel, but I fundamentally disagree with this principle. For an exercise physiologist, I have a pretty good nutrition knowledge base, which has shown me that I do not know anyone, not one person who eats the Recommended Dietary Allowances “by the book”. In a perfect world, we wouldn’t need supplements except in disease and/or preventive states (calcium for osteoporosis, selenium for heart ailments, etc.). I agree that much of the current supplement forms are not very absorbable (except colloidal 98% absorbable), but it would probably be advisable to have all of us taking vitamins and minerals because you and I both know that we will not get the public eating correctly. No way! It just seems logical to recommend people to take vitamin and mineral supplements (which cost about as much as eating out once a month). Sorry to sound cynical, but the “expensive urine” line (which I have used myself) just doesn’t seem to have much merit anymore. Just my opinion though. Thanks for your time!

Generally, vitamin and mineral supplements are not encouraged, due to their low absorption and high cost. Real food is much cheaper and better absorbed than supplements. Unabsorbed nutrients from a supplement are excreted in urine. For people who eat less than 1600 calories per day, it would be difficult to eat enough nutrient-rich foods to achieve the RDA for every nutrient, especially for iron requirements of a menstruating female. Therefore, people who eat less than 1600 calories per day should take a multivitamin that contains 100% of the RDA for all vitamins and minerals as a precaution. Remember though that the RDA’s are set to cover the nutritional needs of 98% of all healthy people living in the United States. So an individual’s need for a particular nutrient may be less. Generally, the minimum intake of a nutrient should be at least 2/3’s of the RDA, which should not be maintained for prolonged periods of time.

What research have you read that substantiates that colloidal minerals are 98% absorbed? I have searched the medical literature as well as searching over 75 nutrition journals and did not find one article on colloidal minerals. To that conclusion, I deemed the information about colloidal minerals to be from testimonials not research.

For your information, a lack of selenium can cause disease of the heart muscle but does not account for all cases of Keshan disease. A toxic virus that attacks the heart muscle may also cause it and a deficiency of selenium may increase a person’s susceptibility to the virus.

As to getting the public to eat correctly, people are intelligent and genuinely want to eat healthy as evidenced by the decrease in fat from 42% in the 1980’s to around 35% today which has caused a corresponding decrease in heart disease in America. I believe in providing the public with information that can improve their health and quality of life as long as it is substantiated by nutrition research. The public needs this information to make healthy food choices.