Human obesity: is insufficient calcium/dairy intake part of the problem?

Epidemiological data have shown that low calcium intake is a risk factor for overweight and obesity. The clinical implications of this relationship have been confirmed in weight loss studies performed in low calcium consumers in whom calcium or dairy supplementation accentuated body weight and fat loss. Up to now, laboratory studies and clinical trials have demonstrated that this effect may be explained by an increase in fat oxidation and fecal loss as well as a facilitation of appetite control. Taken together, these observations suggest that insufficient calcium intake can be part of the obesity problem in some individuals and that an increase in calcium/dairy intake is part of the solution. Key teaching points: Low dietary calcium intake is a significant risk factor for overweight in adults. Calcium/dairy supplementation may accentuate the impact of a weight-reducing program in obese low calcium consumers. Calcium/dairy supplementation promotes fecal fat loss and fat oxidation. Calcium/dairy supplementation favors a decrease in energy intake and a facilitation of appetite control in obese individuals during weight loss.

Milk supplementation facilitates appetite control in obese women during weight loss: a randomised, single-blind, placebo-controlled trial.

Dairy products provide Ca and protein which may facilitate appetite control. Conversely, weight loss is known to increase the motivation to eat. This randomised controlled trial verified the influence of milk supplementation on appetite markers during weight loss. Low Ca consumer women participated in a 6-month energy-restricted programme (-2508 kJ/d or -600 kcal/d) and received either a milk supplementation (1000 mg Ca/d) or an isoenergetic placebo (n 13 and 12, respectively). Fasting appetite sensations were assessed by visual analogue scales. Anthropometric parameters and fasting plasma concentrations of glucose, insulin, leptin, ghrelin and cortisol were measured as well. Both groups showed a significant weight loss (P < 0·0001). In the milk-supplemented group, a time x treatment interaction effect showed that weight loss with milk supplementation induced a smaller increase in desire to eat and hunger (P < 0·05). Unlike the placebo group, the milk-supplemented group showed a lower than predicted decrease in fullness (-17·1 v. -8·8; -2·7 v. 3·3 mm, P < 0·05, measured v. predicted values, respectively). Even after adjustment for fat mass loss, changes in ghrelin concentration predicted those in desire to eat (r 0·56, P < 0·01), hunger (r 0·45, P < 0·05) and fullness (r -0·40, P < 0·05). However, the study did not show a between-group difference in the change in ghrelin concentration in response to the intervention. These results show that milk supplementation attenuates the orexigenic effect of body weight loss.