Dietary Fructose Inhibits Intestinal Calcium Absorption and Induces Vitamin D Insufficiency in CKD
Douard V, Asqerally A, Sabbagh Y, et al. Dietary Fructose Inhibits Intestinal Calcium Absorption and Induces Vitamin D Insufficiency in CKD. J Am Soc Nephrol. 2010;21(2):261-71.
The title of an article, “Dietary Fructose Inhibits Intestinal Calcium Absorption and Induces Vitamin D Insufficiency in CKD,” by Douard et al, published in the February 2010 issue of the Journal of the American Society of Nephrology, is inflammatory. To imply that the condition of patients with chronic kidney disease (CKD) would be worsened by consuming fructose on the basis of a study of 4-6 surgically compromised rats is a disservice. This is compounded by the fact that the animals were fed a diet composed of 60% fructose or glucose which is not only abnormal in rats, but not at all applicable to human consumption of these sugars. Further, humans consume glucose and fructose in combination in the diet, and again, the levels used in this study enormously exceed normal intake in humans.
The typical human intake of fructose from beverages, fruits, vegetables, and other foods is estimated to be 9.1% of total energy intake. Results from studies utilizing treatment applications of extremely high levels of pure fructose are not representative of normal human consumption. Thus, extrapolation to humans cannot be made. The conclusions stated in this paper are unfounded and lead to erroneous information passed on to consumers that normal intake of fructose is linked to chronic kidney disease.
It is articles like the one by Douard et al that are picked up by the media mainly due to the inflammatory nature of the title and conclusions. This leads to consumer confusion. As a result, consumers do not know who or what to believe. Importantly, consumers do not realize that this type of study has no impact with regard to human health.