Background People have come to rely on restaurants and takeaway foods, and less on cooking at home. We examined the association between home cooking and dementia incidence, ascertained through administrative long-term care records, and whether the benefits of home cooking differ by cooking skills. Methods Participants in the Japan Gerontological Evaluation Study, a population-based cohort study, were followed for 6 years. The incidence of dementia was ascertained in 10 978 participants through data from the public long-term care insurance system, which captures functionally significant cognitive impairment requiring care. Cooking frequency and skills were assessed in a baseline survey. Participants with high and low frequencies of home cooking were matched in men and women based on demographic, socioeconomic and health-related factors using propensity score matching. Fine-Grey competing risk models were used, with death treated as a competing event. Results During the follow-up, 1195 dementia cases were found. A total of 1347 male and 321 female pairs were matched between high (at least once a week) and low (less than once a week) cooking frequencies. The subdistribution hazard ratio (SHR) for high cooking frequency (vs low cooking frequency) was 0.77 (95% CI 0.61 to 0.98) in men and 0.73 (95% CI 0.54 to 0.98) in women. The benefits of higher cooking frequency were more pronounced in those with low cooking skills (SHR 0.33, 95% CI 0.13 to 0.84). Conclusions Creating an environment where people can cook meals when they are older may be important for the prevention of dementia.
Tani et al. (Tue,) studied this question.