Dietary lactose and galactose intakes are associated with a later onset of natural menopause among women in a Japanese community

Abstract

Galactose and its metabolites, primarily derived from lactose, may have toxic effects on the ovary. We aimed to prospectively examine the associations of galactose and lactose intakes with the onset of natural menopause. The data of a population-based cohort study in a Japanese community (the Takayama study) initiated in 1992 was analyzed, with follow-up data collected in 2002. Among the participants of the Takayama study, premenopausal women (n=3,115) aged 35–56 years at baseline were included in this study. Dietary intake including lactose and galactose was assessed only at baseline using a food frequency questionnaire. The menopausal status and age at menopause were determined based on the participants’ self-reports, and natural menopause was defined as the absence of menstruation for 12 months or more. Cox proportional hazards models were used to estimate the hazard ratios (HR) and 95% confidence intervals (CI). A total of 1,790 women experienced natural menopause within the 10-year follow-up. Lactose and galactose intakes were associated with a later onset of natural menopause after adjusting for potential confounding factors and the HRs (95% CIs) for the highest vs. lowest quartile were 0.80 (0.69–0.92) (P-trend = 0.001) in lactose and 0.86 (0.74–1.00) in galactose (P-trend = 0.036), respectively. High intakes of lactose and galactose were associated with a later onset of natural menopause. Despite the presumed ovotoxicity effects, lactose and galactose intakes at usual levels may not be deleterious to the ovarian aging process among Japanese community-dwelling women.

The Role of Lifestyle and Dietary Factors in the Development of Premature Ovarian Insufficiency

“…Furthermore, the study showed that lactose and free galactose intakes were also associated with a lower annual reduction in AMH [ 145 ]. This was further supported by a recent study showing high intake of galactose, and lactose was associated with the later onset of natural menopause in Japanese women [ 146 ].…”

Dietary Intake of Fructooligosaccharides Protects against Metabolic Derangements Evoked by Chronic Exposure to Fructose or Galactose in Rats

“…The daily consumption of galactose has been estimated at 1.5–3.6 g d −1 in a female population in Iran [ 7 ] and below 0.5 g d −1 in 75% of women in a Japanese cohort. [ 8 ] The metabolism of galactose results in intermediate products that accumulate and may evoke long‐term metabolic complications and degenerative changes that also occur in aging. [ 9 ] Therefore, galactose injection has been widely used to induce and study the effects of accelerated aging in animal models.…”