Journal of Nutrition & Food Sciences
Open Access

Abstract

Controversies in Vitamin D Recommendations and Its Possible Roles in Nonskeletal Health Issues

Joy L Post and Jasminka Z Ilich Ernst

This article discusses one of the current most controversial nutrition topics. Recent vitamin D recommendations, as well as the serum 25-hydroxyvitamin D (25OHD) concentrations and implications on health status are reviewed. The various functions of vitamin D, starting from the cellular level, through autoimmune diseases, cancer, cardiovascular disease, and neuromuscular processes, to its role in obesity and metabolic syndrome, as well as in pregnancy outcomes, are also discussed. The most up-to-date literature published in peer-review scientific journals was reviewed. While the role of vitamin D in bone metabolism and the amount to support bone health is unequivocal, its benefits and/or roles in various other health conditions and the best way to achieve and maintain optimal levels are still controversial. Opinions vary on the recommended intake for vitamin D and what the desirable serum levels of vitamin D may be. Despite the numerous reports about its impact in autoimmune processes, several cancers, cardiovascular diseases, obesity, metabolic syndrome, and pregnancy complications, the evidence is not robust enough to draw definite conclusions or to establish a causal relationship. Only the role of vitamin D in neuromuscular functions and prevention of falls in frail elderly seems to be more substantiated. Reaching the current or even higher levels of consumption (e.g. 1500-2000 IU/day) seems improbable by food and sun exposure only and supplementation should be in place, particularly for individuals at risk, including breast-fed infants, children, pregnant/lactating women, elderly, obese and individuals with fat mal absorption.