Orange juice providing a daily 1050 mg dose of calcium and 300 IU vitamin D was associated with a significant reduction in visceral adipose tissue in overweight and obese adults, compared with adults drinking a non-fortified juice, according to findings published in the American Journal of Clinical Nutrition.
The apparent body-fat reducing effects of the vitamin and mineral enriched drink was also observed in a ‘lite’ version of the orange juice beverage, report researchers led by Massachusetts General Hospital’s Lee Kaplan, MD, PhD.
“These randomized controlled trials provide further evidence of a role for calcium and vitamin D supplementation in the selective reduction of visceral fat and indicate that calcium and/or vitamin D may contribute to the regulation of lipid metabolism and/or fat distribution,” they wrote.
Fortified juice
The study was funded by the National Institute of Diabetes and Digestive and Kidney Diseases, Beverage Institute for Health & Wellness of The Coca-Cola Company, and the Massachusetts General Hospital Weight Center.
The Coca-Cola Company has been active in supporting research into the vitamin D and calcium fortification of juices, and fortified versions of brands like Minute Maid are already commercially available.
Last year, other Boston-based researchers also reported in the American Journal of Clinical Nutrition (doi: 10.3945/ajcn.2009.27972) that vitamin D in the D2 or D3 form is “equally bioavailable in orange juice and capsules”.
New data
For the new study, Dr Kaplan and his co-workers recruited 171 overweight and obese people with an average age of 40 to participate in their two 16-week parallel, double-blind, placebo-controlled trials. One trial involved the regular beverage and the second trial involved the reduced-energy (lite) version.
The test groups consumed three 240 mL glasses of the regular or lite orange juice per day. The total daily dose of calcium was 1050 mg and 100 IU vitamin D per serving. The control groups were given the same juices but without the addition of the vitamin and mineral.
Results showed that the visceral adipose tissue in people consuming the regular fortified orange juice decreased by an average of 12.7 cm2, compared with only 1.3 cm2 in the control regular juice.
In addition, the lite fortified juice group displayed visceral adipose tissue reductions of 13.1 cm2, compared with 6.4 cm2 in the lite control group.
On the other hand, no differences between any of the groups were recorded in terms of average weight loss, reported Dr Kaplan and his co-workers.
“Our results suggest that, in overweight and obese adults, a moderate reduction in energy intake and supplementation of calcium and vitamin D in juice beverages lead to a reduction in intraabdominal fat,” wrote the researchers.
“A large portion of the population is deficient in vitamin D, and dietary calcium intake often does not meet current recommendations. Although more needs to be learned about the role of calcium and vitamin D in lipolysis, the data underscore the possible role of these 2 nutrients in fat metabolism and support a potential role of calcium and vitamin D in the preferential and beneficial reduction of visceral adipose tissue, which has been linked to several metabolic disorders,” they concluded.
Real?
Commenting on the study, Harry Rice, PhD, VP of regulatory & scientific affairs for the United Natural Products Alliance (UNPA) told NutraIngredients-USA that, while the visceral adipose tissue reduction was greater in the experimental groups compared to the control groups, the standard deviations always exceeded the means, "which leaves me wondering if this a real effect".
Source: American Journal of Clinical Nutrition
Published online ahead of print, doi: 10.3945/ajcn.111.019489
Authors: J.L. Rosenblum, V.M. Castro, C.E. Moore, L.M. Kaplan