Background:The extent to which moderate overweight (body mass index [BMI], 25.0-29.9 [calculated as weight in kilograms divided by height in meters squared]) and obesity (BMI, Ն30.0) are associated with increased risk of coronary heart disease (CHD) through adverse effects on blood pressure and cholesterol levels is unclear, as is the risk of CHD that remains after these mediating effects are considered.Methods: Relative risks (RRs) of CHD associated with moderate overweight and obesity with and without adjustment for blood pressure and cholesterol concentrations were calculated by the members of a collaboration of prospective cohort studies of healthy, mainly white persons and pooled by means of random-effects models (RRs for categories of BMI in 14 cohorts and for continuous BMI in 21 cohorts; total N = 302 296).Results: A total of 18 000 CHD events occurred during follow-up. The age-, sex-, physical activity-, and smoking-adjusted RRs (95% confidence intervals) for moderate overweight and obesity compared with normal weight were 1.32 (1.24-1.40) and 1.81 (1.56-2.10), respectively. Additional adjustment for blood pressure and cholesterol levels reduced the RR to 1.17 (1.11-1.23) for moderate overweight and to 1.49 (1.32-1.67) for obesity. The RR associated with a 5-unit BMI increment was 1.29 (1.22-1.35) before and 1.16 (1.11-1.21) after adjustment for blood pressure and cholesterol levels.Conclusions: Adverse effects of overweight on blood pressure and cholesterol levels could account for about 45% of the increased risk of CHD. Even for moderate overweight, there is a significant increased risk of CHD independent of these traditional risk factors, although confounding (eg, by dietary factors) cannot be completely ruled out.

Lifestyle interventions can reduce body weight, but weight regain is common and may particularly occur with higher initial weight loss. If so, one may argue whether the 10% weight loss in clinical guidelines is preferable above a lower weight loss. This systematic review explores the relation between weight loss during an intervention and weight maintenance after at least 1 year of unsupervised follow-up. Twenty-two interventions (during at least 1 month) in healthy overweight Caucasians were selected and the mean percentages of weight loss and maintenance were calculated in a standardized way. In addition, within four intervention groups (n > 80) maintenance was calculated stratified by initial weight loss (0-5%, 5-10%, >10%). Overall, mean percentage maintenance was 54%. Weight loss during the intervention was not significantly associated with percentage maintenance (r = -0.26; P = 0.13). Percentage maintenance also not differed significantly between interventions with a weight loss of 5-10% vs. >10%. Consequently, net weight loss after follow-up differed between these categories (3.7 vs. 7.0%, respectively; P < 0.01). The analyses within the four interventions confirmed these findings. In conclusion, percentage maintenance does not clearly depend on initial weight loss. From this perspective, 10% or more weight loss can indeed be encouraged and favoured above lower weight loss goals.

The reproducibility, relative validity, and responsiveness to change of an eight-item food frequency questionnaire designed to measure fruit and vegetable consumption was assessed among 157 women (mean age = 41 years) in the Netherlands from spring 2001 to spring 2002. Plasma concentrations of vitamin C and total and specific carotenoids served as biomarkers against which validity was assessed. The questionnaire was completed and biomarker concentrations were determined three times: immediately preceding and following a controlled intervention of 1 month aimed at increasing fruit and vegetable consumption and 1 year after the start of the intervention. The 1-month and 1-year reproducibility of total fruit and vegetable consumption assessed in the control group was 0.80 and 0.79 (Spearman's r ). Correlations between consumption and plasma carotenoids and vitamin C at baseline were 0.39 and 0.37, respectively, for fruits and 0.24 and 0.26, respectively, for vegetables. Correlations between changes in consumption and plasma carotenoids and vitamin C were 0.32 and 0.33, respectively, for fruits and 0.28 and 0.30, respectively, for vegetables. On the basis of similar correlations reported in the literature, the authors conclude that the questionnaire appears to be suitable for ranking individuals according to their consumption of fruits and vegetables and according to changes in their consumption. However, the validity of the questionnaire remains to be established in males, other age groups, and populations of lower educational levels.

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In this study, BMI was associated with all-cause mortality risk in older people. This risk was mostly driven by an increased cardiovascular mortality risk, as no association was found for mortality risk from cancer or respiratory disease. Our results indicate that the WHO cut-off point of 25 kg/m² for overweight might be too low in old age, but more studies are needed to define specific cut-off points.