Type of Vegetarian Diet, Body Weight and Prevalence of Type 2 Diabetes.

April 16, 2009

Tonstad S, Butler T, Yan R, Fraser GE.

Loma Linda University, Departments of Health Promotion and Education, School of

Public Health and Preventive Medicine, School of Medicine (Dr. Tonstad).

Objective: We assessed the prevalence of type 2 diabetes in people following

different types of vegetarian diets compared to non-vegetarians. Research Design

and Methods: Study participants were 22 434 men and 38 469 women who

participated in the Adventist Health Study-2 conducted in 2002-6. We collected

self-reported demographic, anthropometric, medical history and lifestyle data

from Seventh day Adventist church members across North America. The type of

vegetarian diet was categorized based on a food frequency questionnaire. We

calculated odds ratios (ORs) and 95% confidence intervals (CIs) using

multivariate-adjusted logistic regression. Results: Mean BMI was lowest in

vegans (23.6 kg/m(2)) and incrementally higher in lacto-ovo vegetarians (25.7),

pesco vegetarians (26.3), semi-vegetarians (27.3) and non-vegetarians (28.8).

Prevalence of type 2 diabetes increased from 2.9% in vegans to 7.6% in

non-vegetarians; prevalences were intermediate in participants consuming

lacto-ovo (3.2%), pesco (4.8%) or semi-vegetarian (6.1%) diets. After adjustment

for age, gender, ethnicity, education, income, physical activity, TV watching,

sleep habits, alcohol use and BMI, vegans (OR 0.51, 95% CI 0.40-0.66), lacto-ovo

vegetarians (OR 0.54, 95% CI 0.49-0.60), pesco vegetarians (OR 0.70, 95% CI

0.61-0.80) and semi-vegetarians (OR 0.76, 95% CI 0.65-0.90) had a lower risk of

type 2 diabetes than non-vegetarians. Conclusions: The five unit BMI difference

between vegans and non-vegetarians indicates a substantial potential of

vegetarianism to protect against obesity. Increased conformity to vegetarian

diets protected against risk of type 2 diabetes after lifestyle characteristics

and BMI were taken into account. Pesco and semi-vegetarian diets afforded

intermediate protection.

PMID: 19351712 [PubMed - as supplied by publisher]

Recommended Posts