Vitamin D and Calcium Intake in Relation to Type 2 Diabetes in Women

Abstract

OBJECTIVE -The purpose of this study was to prospectively examine the association between vitamin D and calcium intake and risk of type 2 diabetes.RESEARCH DESIGN AND METHODS -In the Nurses' Health Study, we followed 83,779 women who had no history of diabetes, cardiovascular disease, or cancer at baseline for the development of type 2 diabetes. Vitamin D and calcium intake from diet and supplements was assessed every 2-4 years. During 20 years of follow-up, we documented 4,843 incident cases of type 2 diabetes.RESULTS -After adjusting for multiple potential confounders, there was no association between total vitamin D intake and type 2 diabetes. However, the relative risk (RR) of type 2 diabetes was 0.87 (95% CI 0.75-1.00; P for trend ϭ 0.04) comparing the highest with the lowest category of vitamin D intake from supplements. The multivariate RRs of type 2 diabetes were 0.79 (0.70 -0.90; P for trend Ͻ0.001) comparing the highest with the lowest category of calcium intake from all sources and 0.82 (0.72-0.92; P for trend Ͻ0.001) comparing the highest with the lowest category of calcium intake from supplements. A combined daily intake of Ͼ1,200 mg calcium and Ͼ800 IU vitamin D was associated with a 33% lower risk of type 2 diabetes with RR of 0.67 (0.49 -0.90) compared with an intake of Ͻ600 mg and 400 IU calcium and vitamin D, respectively.CONCLUSIONS -The results of this large prospective study suggest a potential beneficial role for both vitamin D and calcium intake in reducing the risk of type 2 diabetes. Diabetes Care 29:650 -656, 2006T here is evidence to suggest that altered vitamin D and calcium homeostasis may play a role in the development of type 2 diabetes. The role of vitamin D in type 2 diabetes is suggested by cross-sectional studies showing that low serum concentrations of 25-hydroxyvitamin D [25(OH)D] are associated with impaired glucose tolerance and diabetes (1-3). The role of calcium in the development of type 2 diabetes is suggested indirectly by cross-sectional studies in which high calcium intake has been found to be inversely associated with body weight and fatness (4 -6). The results from small clinical trials have been inconsistent (7-11).The purpose of the present study was to prospectively evaluate the association between vitamin D and calcium intake and the risk of type 2 diabetes in a large cohort of women followed for 20 years. For the present analysis, follow-up began in 1980, when the first dietary questionnaires were mailed to women who were free of diabetes, coronary heart disease, stroke, or cancer. After excluding participants with incomplete data on variables required for the analysis, a total of 83,779 women contributed to the analysis with follow-up completed in June 2000. RESEARCH DESIGN AND METHODS Assessment of dietary intakeDietary intake was assessed with the semiquantitative validated Food Frequency Questionnaire (13), first in 1980 and subsequently in 1984, 1986, 1990, 1994, and 1998. Dietary intake of vitamin D, calcium, and other nutrients was calculated by multip...

Serum calcium is independently associated with insulin sensitivity measured with euglycaemic–hyperinsulinaemic clamp in a community-based cohort

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“…To answer these questions, we investigated the relationships between the serum levels of calcium and insulin sensitivity, evaluated using the hyperinsulinaemic-euglycaemic clamp, and secretion, evaluated as the early insulin response (EIR) during an OGTT, in a population-based cohort of elderly men with emphasis on subgroup analyses in individuals with normal fasting glucose, normal glucose tolerance and normal serum calcium. As a secondary aim, we also investigated the association between dietary intake of calcium and insulin sensitivity and secretion, as previous studies have suggested that higher dietary intake of calcium is associated with a lower risk of developing diabetes [14].…”

The effect of different doses of vitamin D3 on markers of vascular health in patients with type 2 diabetes: a randomised controlled trial

“…Low vitamin D levels are common in patients with type 2 diabetes [1], over 50% of whom have a serum 25 hydroxyvitamin D (25OHD) level of <50 nmol/l [2,3]. Low vitamin D levels are associated with a higher risk of developing type 2 diabetes [4], worse glycaemic control in type 2 diabetes, higher serum lipid levels and a higher prevalence of cardiovascular disease [3]. Low vitamin D levels are also associated with an increased risk of hypertension and cardiovascular events in population-based studies [5][6][7][8].…”

No association between 25-hydroxyvitamin D levels and prediabetes in Brazilian patients. A cross-sectional study

“…8,9 Several clinical studies have evaluated the role of low 25OHD3 in the pathogenesis of T2DM, but with controversial results. [10][11][12][13][14][15] Recently, a study has looked into prediabetes and 25OHD3 in a representative population in the United States. This study reported that low serum 25OHD3 levels were associated with prediabetes in that population, with a strong correlation when vitamin D levels were lower than 17 ng/ml.…”