Caloric restriction reduces age at menopause: the effect of the 1944-1945 Dutch famine

Objective: To assess the effect of caloric restriction, as endured during the 1944-1945 Dutch famine, on the age at which natural menopause occurs and to identify specific vulnerable age periods in which caloric restriction has the largest effect. Design: This was a population-based cohort study conducted in Utrecht, the Netherlands. Between 1983 and 1986, 9,471 women aged 40 to 73 years at the time of interview were classified regarding their exposure to the famine. Age at natural menopause was obtained from all available data, retrospectively as well as prospectively. We estimated differences in mean age at natural menopause between famine exposure categories (not, moderately, and severely exposed), with adjustment for smoking, parity, socioeconomic status, body mass index, age at menarche, and year of birth. Results: Women experienced natural menopause on average 0.36 years earlier (95% CI: -0.60, -0.11) when severely exposed to the famine and 0.06 years earlier (95% Cl: -0.22, 0.09) when moderately exposed compared with the unexposed women. This effect was particularly pronounced in those severely exposed from 2 to 6 years of age: -1.83 years (95% Cl: -3.03, -0.63). Conclusions: Our findings suggest that caloric restriction decreases age at natural menopause. Early childhood seems to be a particularly sensitive age period for this effect.