Nut and peanut butter consumption and risk of type 2 diabetes in women.
BACKGROUND
Nuts are high in unsaturated (polyunsaturated and monounsaturated) fat and other nutrients that may improve glucose and insulin homeostasis.


OBJECTIVE
To examine prospectively the relationship between nut consumption and risk of type 2 diabetes.


METHODS
Prospective cohort study of 83 818 women from 11 states in the Nurses' Health Study. The women were aged 34 to 59 years, had no history of diabetes, cardiovascular disease, or cancer, completed a validated dietary questionnaire at baseline in 1980, and were followed up for 16 years.


METHODS
Incident cases of type 2 diabetes.


RESULTS
We documented 3206 new cases of type 2 diabetes. Nut consumption was inversely associated with risk of type 2 diabetes after adjustment for age, body mass index (BMI), family history of diabetes, physical activity, smoking, alcohol use, and total energy intake. The multivariate relative risks (RRs) across categories of nut consumption (never/almost never, <once/week, 1-4 times/week, and > or =5 times/week) for a 28-g (1 oz) serving size were 1.0, 0.92 (95% confidence interval [CI], 0.85-1.00), 0.84 (0.95% CI, 0.76-0.93), and 0.73 (95% CI, 0.60-0.89) (P for trend <.001). Further adjustment for intakes of dietary fats, cereal fiber, and other dietary factors did not appreciably change the results. The inverse association persisted within strata defined by levels of BMI, smoking, alcohol use, and other diabetes risk factors. Consumption of peanut butter was also inversely associated with type 2 diabetes. The multivariate RR was 0.79 (95% CI, 0.68-0.91; P for trend <.001) in women consuming peanut butter 5 times or more a week (equivalent to > or =140 g [5 oz] of peanuts/week) compared with those who never/almost never ate peanut butter.


CONCLUSIONS
Our findings suggest potential benefits of higher nut and peanut butter consumption in lowering risk of type 2 diabetes in women. To avoid increasing caloric intake, regular nut consumption can be recommended as a replacement for consumption of refined grain products or red or processed meats.
Jiang
Rui
R
Department of Nutrition, Harvard School of Public Health, 665 Huntington Ave, Boston, MA 02115, USA. rjiang@hsph.harvard.edu
Manson
JoAnn E
JE
Stampfer
Meir J
MJ
Liu
Simin
S
Willett
Walter C
WC
Hu
Frank B
FB
D000328:Adult; D010367:Arachis; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology*; D004032:Diet; D004042:Dietary Fats, Unsaturated; D005260:Female; D006306:Health Surveys; D006801:Humans; D008875:Middle Aged; D015596:Nutrition Assessment; D009754:Nuts; D011446:Prospective Studies; D012306:Risk
D004042:Dietary Fats, Unsaturated