Calcium and dairy intakes in relation to long-term weight gain in US men.

BACKGROUND The role of calcium in the maintenance of body weight remains controversial. OBJECTIVE We investigated the association between calcium and dairy intakes and 12-y weight change in US men. DESIGN This study was conducted with the use of data from the Health Professionals Follow-up Study, a prospective cohort of men aged 40-75 y in 1986. Data on lifestyle factors and diet were updated biennially with self-administered questionnaires. The participants reported their body weight in 1986 and in 1998. The outcome in our study was 12-y weight change. We used multivariate linear regression to examine how baseline calcium intake (n = 23,504) and change in calcium intake (n = 19,615) were associated with weight change. Because dairy foods are the predominant source of calcium in the diet, we also evaluated a similar association with dairy intake. RESULTS In a multivariate analysis with adjustment for potential confounders, baseline or change in intake of total calcium was not significantly associated with weight change. In addition, we did not find any association with dietary, dairy, or supplemental calcium intake when evaluated separately. The men with the largest increase in total dairy intake gained slightly more weight than did the men who decreased intake the most (3.14 compared with 2.57 kg; P for trend = 0.001). This association was primarily due to an increase in high-fat dairy intake. Low-fat dairy intake was not significantly associated with weight change. CONCLUSION Our data do not support the hypothesis that an increase in calcium intake or dairy consumption is associated with lower long-term weight gain in men.