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Body weight and height have both been associated consistently with postmenopausal breast cancer but less consistently with prostate cancer. The present study examined the relationship between body mass index (BMI), height, and death from prostate cancer in two large American Cancer Society cohorts. Men in the study were selected from the male participants in Cancer Prevention Study I (CPS-I; enrolled in 1959 and followed through 1972) and Cancer Prevention Study II (CPS-II; enrolled in 1982 and followed through 1996). After exclusions, 1,590 prostate cancer deaths remained among 381,638 men in CPS-I and 3,622 deaths among 434,630 men in CPS-II. Cox proportional hazards modeling was used to compute rate ratios (RR) and to adjust for confounders. Prostate cancer mortality rates were significantly higher among obese (BMI, > or =30) than nonobese (BMI, <25) men in both cohorts [adjusted RR, 1.27; 95% confidence interval (CI), 1.04-1.56 in CPS-I; RR, 1.21; 95% CI, 1.07-1.37 in CPS-II]. Prostate cancer mortality rates in the CPS-I cohort were lowest for the shortest men (RR, 0.80; 95% CI, 0.63-1.03 for men <65 inches versus 65-66 inches) and highest for the tallest men (RR, 1.39; 95% CI, 1.11-1.74 for men > or =73 inches tall versus 65-66 inches). Rates remained constant among men 65-72 inches tall. No association between height and prostate cancer mortality was observed in the CPS-II cohort (RR, 1.03; 95% CI, 0.82-1.29 for men > or =75 versus 65-66 inches). These results support the hypothesis that obesity increases risk of prostate cancer mortality. Decreased survival among obese men may be a likely explanation for this association.

In observational studies, estrogen replacement therapy is associated with decreased cardiovascular disease rates and increased breast cancer rates. Recent evidence suggests that the impact of estrogen use on disease outcomes may vary by body mass. In a prospective study of 290,827 postmenopausal US women with no history of cancer or cardiovascular disease at enrollment in 1982, the authors examined the association between postmenopausal estrogen use and all-cause, coronary heart disease, stroke, all-cancer, and breast cancer death rates and whether these associations differed by body mass. After 12 years of follow-up, results from Cox proportional hazards models showed that all-cause death rates were lower among baseline estrogen users than never users (rate ratio (RR) = 0.82, 95% confidence interval (CI): 0.78, 0.87). The lowest relative risk was found for coronary heart disease (RR = 0.66, 95% CI: 0.58, 0.77). The inverse association between estrogen use and coronary heart disease mortality was strongest for thin women (body mass index <22 kg/m2) (RR = 0.49, p for interaction = 0.02). Breast cancer mortality did not increase with estrogen use overall, and no increased risk was observed for thin or heavy women. In this population, the reduction in coronary heart disease mortality among estrogen users was greatest for thinner women. Additional studies are needed to confirm or refute these results.

Obesity has been reported to increase the risk of colon cancer, especially in men. The authors examined this relation in the American Cancer Society's Cancer Prevention Study II, a nationwide mortality study of US adults. After 12 years of follow-up, 1,616 deaths from colon cancer in women and 1,792 in men were observed among 496,239 women and 379,167 men who were cancer free at enrollment in 1982. The authors used Cox proportional hazards analyses to control for effects of age, race, education, smoking, exercise, alcohol, parental history of colon cancer, fat intake, vegetable and grain intake, aspirin use and, in women, estrogen replacement therapy. In men, death rates from colon cancer increased across the entire range of body mass index (BMI). The rate ratio was highest for men with BMI > or =32.5 (rate ratio (RR) = 1.90, 95% confidence interval (CI): 1.46, 2.47) compared with men with BMI between 22.00 and 23.49. In women, a weaker association was seen in the three BMI categories of 27.5-29.9 (RR = 1.26, 95% CI: 1.03, 1.53), 30.0-32.4 (RR = 1.37, 95% CI: 1.09, 1.72), and > or =32.5 (RR = 1.23, 95% CI: 0.96, 1.59). These prospective data support the hypothesis that obesity increases the risk of colon cancer death and that the relation is stronger and more linear in men than in women.

Background: Body-mass index (the weight in kilograms divided by the square of the height in meters) is known to be associated with overall mortality. We investigated the effects of age, race, sex, smoking status, and history of disease on the relation between body-mass index and mortality., Methods: In a prospective study of more than 1 million adults in the United States (457,785 men and 588,369 women), 201,622 deaths occurred during 14 years of follow-up. We examined the relation between body-mass index and the risk of death from all causes in four subgroups categorized according to smoking status and history of disease. In healthy people who had never smoked, we further examined whether the relation varied according to race, cause of death, or age. The relative risk was used to assess the relation between mortality and body-mass index., Results: The association between body-mass index and the risk of death was substantially modified by smoking status and the presence of disease. In healthy people who had never smoked, the nadir of the curve for body-mass index and mortality was found at a body-mass index of 23.5 to 24.9 in men and 22.0 to 23.4 in women. Among subjects with the highest body-mass indexes, white men and women had a relative risk of death of 2.58 and 2.00, respectively, as compared with those with a body-mass index of 23.5 to 24.9. Black men and women with the highest body-mass indexes had much lower risks of death (1.35 and 1.21), which did not differ significantly from 1.00. A high body-mass index was most predictive of death from cardiovascular disease, especially in men (relative risk, 2.90; 95 percent confidence interval, 2.37 to 3.56). Heavier men and women in all age groups had an increased risk of death., Conclusions: The risk of death from all causes, cardiovascular disease, cancer, or other diseases increases throughout the range of moderate and severe overweight for both men and women in all age groups. The risk associated with a high body-mass index is greater for whites than for blacks.

Objectives: The purpose of this study was to identify behaviors associated with change in body mass index or with weight gain at the waist., Methods: A cohort of 79236 White, non-Hispanic, healthy adults was questioned in 1982 and 1992 about diet and 10 physical activities. Estimates were made of the mean effects of stable behaviors on 10-year change in body mass index and on odds ratios for gain at the waist., Results: Ten-year changes in body mass index was associated positively with meat consumption and smoking cessation and inversely with vegetable consumption, vitamin E supplementation, continued smoking, and some vigorous activities (e.g., jogging/running). Women's body mass index decreased with walking 4 or more hours per week and with regular alcohol intake, but these behaviors had a smaller effect on men's body mass index. weight gain was inversely associated with high vegetable consumption, walking 4 or more hours per week, and jogging/running 1 to 3 hours per week but not with less demanding physical activities., Conclusions: Simple derivation of behaviors associated with weight loss or reduced abdominal obesity may enhance programs designed to prevent obesity and chronic diseases.