Effect of Short-Term High Dietary Calcium Intake on 24-h Energy Expenditure, Fat Oxidation, and Fecal Fat Excretion

Int J Obes (Lond). 2005 Mar;29(3):292-301. doi: 10.1038/sj.ijo.0802785.

Abstract

Background: Observational studies have shown an inverse association between dietary calcium intake and body weight, and a causal relation is likely. However, the underlying mechanisms are not understood.

Objective: We examined whether high and low calcium intakes from mainly low-fat dairy products, in diets high or normal in protein content, have effects on 24-h energy expenditure (EE) and substrate oxidation, fecal energy and fat excretion, and concentrations of substrates and hormones involved in energy metabolism and appetite.

Design: In all, 10 subjects participated in a randomized crossover study of three isocaloric 1-week diets with: low calcium and normal protein (LC/NP: 500 mg calcium, 15% of energy (E%) from protein), high calcium and normal protein (HC/NP: 1800 mg calcium, 15E% protein), and high calcium and high protein (HC/HP: 1800 mg calcium, 23E% protein).

Results: The calcium intake had no effect on 24-h EE or fat oxidation, but fecal fat excretion increased approximately 2.5-fold during the HC/NP diet compared with the LC/NP and the HC/HP diets (14.2 vs 6.0 and 5.9 g/day; P < 0.05). The HC/NP diet also increased fecal energy excretion as compared with the LC/NP and the HC/HP diets (1045 vs 684 and 668 kJ/day; P < 0.05). There were no effects on blood cholesterol, free fatty acids, triacylglycerol, insulin, leptin, or thyroid hormones.

Conclusions: A short-term increase in dietary calcium intake, together with a normal protein intake, increased fecal fat and energy excretion by approximately 350 kJ/day. This observation may contribute to explain why a high-calcium diet produces weight loss, and it suggests that an interaction with dietary protein level may be important.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Anthropometry
  • Body Weight / drug effects*
  • Body Weight / physiology
  • Calcium, Dietary / administration & dosage
  • Calcium, Dietary / pharmacokinetics
  • Calcium, Dietary / pharmacology*
  • Cross-Over Studies
  • Dairy Products / analysis
  • Diet
  • Dietary Fats / pharmacokinetics*
  • Dietary Proteins / administration & dosage
  • Energy Metabolism / drug effects*
  • Energy Metabolism / physiology
  • Feces / chemistry
  • Female
  • Humans
  • Lipids / blood
  • Male
  • Middle Aged
  • Nutritional Physiological Phenomena / physiology
  • Oxidation-Reduction / drug effects

Substances

  • Calcium, Dietary
  • Dietary Fats
  • Dietary Proteins
  • Lipids