Author Affiliations: Departments of Epidemiology and Nutrition, Harvard School of Public Health, Boston, Mass.
Nearly 50 years ago, Keys1,2 recognized
the enormously divergent rates of heart disease around the world, even after
adjusting for differences in age. Although coronary disease was and remains
the leading cause of death in the United States and many developed and developing
countries, it was almost nonexistent in the traditional cultures of Crete
and Japan.1 Rates of cancer at various sites
also differ enormously—up to 100-fold—in different populations.3 The rapid changes in rates of many of these diseases
over time and studies that show increases in chronic disease rates among migrants
from traditional to Westernized cultures demonstrate that relatively swift
changes in disease rates cannot be attributed solely to genetic differences
between populations.4 Instead, they are likely
due to differences in lifestyle, with dietary factors and physical activity
the leading candidates.
Rimm EB, Stampfer MJ. Diet, Lifestyle, and Longevity—The Next Steps?. JAMA. 2004;292(12):1490–1492. doi:10.1001/jama.292.12.1490