Comparison of Dietary Supplement Users Vs. Non-Users

This particular blog post is titled, “Let them eat cake!” for reasons which I am still not quite sure.  However, the topic of this most recent blog post is a comparison of people who use dietary supplements to those who do not.

I recently read an article in the Nutrition Journal which compared usage patterns, health, and nutritional status of long-term multiple dietary supplement users in the form of a cross-sectional study.  A cross-sectional study compares a sample population to a control population at one point in time.

This particular study consisted of individuals who took dietary supplements for a 20 year period on a daily basis.  Supplements taken by on a daily basis by more than 50% of this group included a multivitamin/mineral, B-complex vitamin, vitamin C, carotenoids, vitamin E, Calcium with Vitamin D, omega-3 fatty acids, flavonoids, lecithin, alfalfa, coenzyme Q10 with reservatrol, glucosamine, and an herbal immune supplement.

In addition to multiple supplement group taking many of these dietary supplements, there were some other characteristics inherent in this group which were different from the control group.  The multiple dietary supplement group consisted of 80% of people who had >high school education vs (54.2%) of the people who did not take dietary supplements.

Further, the multiple dietary supplement group also had a higher annual income level.  In conclusion, the multiple dietary supplement users had both higher educational levels as well as income levels, both of these measures were statistically significant.

Though one could certainly reasonably question the validity of this study given that the control group had both lower education and income levels, two factors which independently are associated with poor health status, the dietary supplement group was approximately ten years older on average.

In a nutshell, the dietary supplement user group consisted of somewhat more educated individuals with higher income levels which would likely have a positive influence on their health status, however, this is probably mitigated by their significantly older age which itself is essentially a risk factor for lower health status.

The dietary supplement group differed both in serum nutrient concentration as well as biomarker status.  Not surprisingly, the multiple dietary supplement user group had higher serum nutrient concentrations compared to the control group including serum concentrations of ascorbic acid (vitamin C), alpha and beta carotene, alpha tocopherol (vitamin E), and serum retinol.

Biomarkers including elevated levels of both C-reactive protein (CRP) as well as serum homocysteine are considered important markers of cardiovascular disease risk.  In addition to lower levels of CRP, serum homocysteine, the multiple dietary supplement users also had lower levels of cholesterol and blood pressure.  In fact, dietary supplement use was also associated with higher HDL cholesterol concentration which is considered to the “good cholesterol.”

Higher HDL levels reduce cardiovascular disease risk.  In this study, the multiple dietary supplement users also had a lower incidence of diabetes which the study authors suggested is consistent with evidence that oxidative stress may be a mechanism linking insulin resistance with dysfunction of the pancreas eventually leading to diabetes.

Considering that the multiple dietary supplement user group had lower blood pressure, cholesterol, triglycerides, homocysteine levels, CRP levels, as well as a lower incidence of diabetes, perhaps, we should let them eat cake!

The study authors suggested that these findings should be confirmed by studying other groups of multiple dietary supplement users.

Reference:

  1. Block G, Jensen CD, Norkus EP, Dalvi TB, Wong LG, McManus JF, Hudes ML.  Usage patterns, health, and nutritional status of long-term multiple dietary supplement users: a cross-sectional study.  Nutr J. 2007 Oct 24;6:30.