Vitamin D: MUFA vs PUFA

Our Vitamin D3 compound is unique in a number of ways, but most notably is our addition of "MUFA" and BioPerine® to the mix. BioPerine® is a patented, standardized extract obtained from black pepper containing not less than 95% piperine. This Sabinsa® branded product is a clinically proven bio-availability enhancer for nutrients. The addition of BioPerine® has been shown to boost nutrient absorption and action as much as five fold. Next is our addition of a healthy form of "MUFA" (MONO-unsaturated fatty acid) in our blend. For years scientists and nutritionists thought that the addition of "PUFA" (POLY-unsaturated fatty acids) would enhance the absorption of D3. The latest findings have shown that "PUFA" actually reduces the absorption of D3, while "MUFA" has a pronounced benefit of increased D3 uptake. As of this writing, we could find no other vitamin D3 product on the market with our beneficial blend. For further documentation on this subject, we have included additional information below.

Vitamin D & PUFA - Is There an Overlooked Antagonism Between Polyunsaturated Fatty Acids and Vitamin D3?

In essence a regression model consists of a system of several sets of loosely predefined partial differential equations (e.g. logarithmic, linear, polynomial, etc.), the scientists, or rather their computers (in this particular study, the SPSS software package was used for statistical analyses) solve using the experimentally established data. Although statistical analyses like this allow for literally unlimited adjustments for confounding variables, such as body weight, total energy intake, etc., the underlying models are still in and out of themselves theoretical constructs that are based on certain hypothesis and assumptions. Thus, any "associations" of parameter A and outcome B, which are usually expressed in the form of regression coefficients (larger coefficient = greater explanatory power), are valid only if all the underlying assumptions hold true. Sathi Niramitmahapanya and his colleagues from the U.S. Department of Agriculture Human Nutrition Research Center on Aging at Tufts University found an interesting and previously not thought of negative correlation between their subjects' plasma levels of 25-hydroxyvitamin D 25(OH)D levels and the ratio of poly- to monounsaturated fatty acids in their diets (Niramitmahapany. 2011). Could it be that you have to choose, when it comes to high vitamin D or PUFA intake?

Since this was not a specifically designed experiment, Niramitmahapany et al. had to rely on the data that had already been gathered in a 3-year, randomized, double-blind, placebo-controlled trial, originally designed to determine the effect of supplemental vitamin D + calcium on rates of bone loss and fractures in 152 men and women (age >65years). Consequently, the study relies heavily on the accuracy of complex regression analysis, by the means of which the Tuft researchers tried to figure out which of the handful of confounding variables they had surveyed, had the greatest influence, or I should say statistically measurable explanatory value for the effect of vitamin D3 supplementation on serum 25-hydroxyvitamin D levels in their elderly subjects.

Out of the parameters Niramitmahapany et al. evaluated, the only independent variable with a significant impact on the effect of supplemental vitamin D3 on serum levels was the composition (not the absolute amount!) of the fats in the subjects' diets.

Figure 1: Statistically modeled regression coefficients of total fat intake and MUFA/PUFA ratio; adjusted for baseline BMI, 25(OH)D levels, total energy intake (data adapted from Niramitmahapany.. 2011)

As the regression coefficients in figure 1 clearly show, neither the absolute amount of fats nor the absolute amount of an individual type of dietary fat (monounsaturated, MUFA; polyunsaturated, PUFA; saturated fatty acids, SFA) are adequate predictors of serum 25(OH)D levels. The ratio of monounsaturated to polyunsaturated fatty acids (MUFA / PUFA ratio) on the other hand turned out to be a pretty reliable predictor of the amount of active vitamin D in the sera of the study participants. This was all the more the case if possible influences of saturated fatty acids were taken into account in the model, as well.

Now, statistics and "associations" are one thing, mechanisms and "causations" are yet another; and obviously the latter, i.e. cause-and-effect relations and determinisms, are what humans, in general, and natural scientists, in particular, have been striving for even before the early days of natural science in the ancient times. Thus, I assume you will be interested to hear, what the scientists have to say with regard to the underlying mechanisms of the statistical "association" they observed:

The mechanisms by which fatty acid intake may influence vitamin D3 absorption have not been completely delineated. Most of the available evidence comes from early work by Hollander and colleagues (Hollander. 1981). Their gut perfusion studies in the rat revealed that vitaminD3 is absorbed by passive diffusion in the proximal jejunumand the distal ileum (10). Absorption of physiological doses of vitamin D3 in rats was reduced by 30%in the presence of a 4-fold increase in luminal fat (Hollander. 1978; 1981), and consistent with our findings, the PUFA, linoleic and linolenic acids, were particularly effective in decreasing vitaminD3 absorption (Hollander. 1978). Hollander offered several potential explanations for why these fatty acids impaired vitamin D3 absorption. They may have increased the solubility of vitamin D3 in the micelles and changed the partition coefficient such that the vitamin D3 stayed in the micelle. Alternatively, they may have increased the size of the micelle and thereby reduced its diffusion rate and increased its difficulty in crossing the unstirred water layer lining the intestinal mucosa.

I suppose, what you just read about how dietary fat impairs the absorption of vitamin D goes against all you have hitherto heard from the same "experts" and "gurus" who have been telling you to take 20g of fish oil and 20.000IU of vitamin D, each day. Well, in their defense, it should be said that small amounts of dietary fat are actually beneficial, probably even essential for the uptake of the so-called "fat-soluble" vitamins A, D, K (and probably even E), BUT its obviously not the fat that "drives" or "carries" the vitamins into your blood stream, but the bile acid that is secreted in order to digest the former, which helps with / is necessary for the absorption of these, in the true sense of the word, vital nutrients.

So, while it appears quite clear that the general effect of large amounts of fat taken with physiological doses of vitamin D is a negative one, the scientists cannot explain why mono-unsaturated fatty acids seem to be an exception to the way the other fats (and PUFAs in particular) appear to negatively affect micelle content or migration rate of fat-soluble vitamins in the intestines. Yet, whatever the mechanism may be, an increase or, after all, a reduced decrease in vitamin D3 absorption from the gut may yet be another of the hitherto established health benefits of the long-overlooked mono-unsaturated fatty acids.