|Van Loan, Marta|
Submitted to: Nutrients
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/30/2009
Publication Date: 9/3/2009
Citation: Zemel, M.B., Teegarden, D., Van Loan, M.D., Schoeller, D., Matkovic, V., Lyle, R., Craig, B. 2009. DAIRY-RICH DIETS AUGMENT FAT LOSS ON AN ENERGY-RESTRICTED DIET: A MULTICENTER TRIAL. Nutrients 2009, 1, 83-100. Interpretive Summary: Obesity is the leading public health problem in America and is growing in magnitude. However, the obesity epidemic is a multifaceted problem requiring novel approaches to its resolution. We conducted a 12-week weight loss project with 105 overweight and obese men and women who were habitually low consumer of dairy-rich foods to determine if increased calcium intake from dairy-rich foods would increase the amount of weight and body fat lost. A moderate energy restriction of 500 calories was implemented for all treatment groups. In addition, one treatment group received 3 additional servings of dairy foods, a second treatment group received a calcium supplement and the 3rd group had energy restriction without any additional calcium or dairy foods. We found that the greatest amount of weight and fat loss occurred in the dairy-rich treatment group. A further benefit observed in the dairy-rich group was that more fat was lost from the truck region of the body. This finding is of particular importance because excess fat accumulated on the truck region or upper body is associated with increased cardiovascular disease. These findings suggest that the inclusion of 3-4 servings of dairy-rich foods in a moderate energy restricted diet can improve weight and fat loss in overweight and obese adult men and women.
Technical Abstract: We previously found calcium and dairy-rich diets to modulate adipocyte lipid metabolism, thereby accelerating weight loss during energy restriction. We have now evaluated these concepts in a 12-week randomized controlled multi-center clinical trial of 105 overweight and obese adults. Diets were designed to produce a 500 kcal/day energy deficit with either low calcium (LC; ~600 mg/day), high calcium (HC; ~1,400 mg/day), or high dairy (HD; 3 dairy servings, diet totaling ~1,400 mg/day). Macronutrients were maintained at the US average. Ninety-three subjects completed the trial, and 68 met all a priori weekly compliance criteria. Although both HC and HD contained comparable levels of calcium and suppressed 1,25-(OH)2D levels (p<0.001), HC was only ~30% as effective as HD in suppressing 1,25-(OH)2D and exerted no significant effects on weight loss or body composition compared to LC. In the adherent group, HD resulted in ~two-fold augmentation of fat loss compared to LC and HC (HD:-4.43+0.53 kg; LC:-2.69+0.0.53 kg; HC:-2.23+0.73kg, p<0.025); assessment of all completers and an intent-to-treat analysis produced similar results. Weight loss was similarly augmented in the adherent group by HD vs. HC or LC (HD: -4.62+0.63 kg; LC: -3.15+0.62 kg; HC:-2.27+0.87 kg, p=0.08). HD also resulted in a marked augmentation of central (trunk) fat loss (HD:-2.38+0.30 kg; HC:-1.42+0.30 kg; LC:-1.36+0.42 kg, p<0.05) and waist circumference (HD:-7.65+0.75 cm; LC:-4.92+0.74 cm; LC:-4.95+1.05 cm, p<0.025) compared to HC or LC. Similar effects were noted among all subjects completing the study and in an intent-to-treat analysis. HD resulted in a non-significant preservation of lean mass during energy restriction compared to the other groups. We conclude that dairy-rich diets augment weight loss by targeting the fat compartment during energy restriction.