As a result of the coronavirus disease 2019 (COVID-19) pandemic-related restrictions, food systems have undergone unprecedented changes, with the potential to affect dietary behavior. We aimed to investigate workers’ dietary changes resulting from the introduction of regulations to combat COVID-19 in a Japanese factory cafeteria. Objective data on daytime dietary intake were automatically collected from electronic purchase system records. The dataset included the weekly data of 890 men from 1 July 2019 to 30 September 2020. The cafeteria regulations came into effect on 10 April 2020; in this context, the purchase of dishes and estimated dietary intake were monitored. The number of cafeteria visits decreased slightly after the introduction of the regulations. The purchase of main and side dishes also decreased, but the purchase of grain dishes was less affected. When compared with summer 2019 (pre-pandemic, no regulations: 1 July to 29 September 2019), in summer 2020 (during the pandemic and with regulations: 29 June to 30 September 2020), the estimated mean grain, meat, fish, and total energy intake was stable; however, vegetable intake decreased by 11%. As the COVID-19 pandemic continues, workplace cafeteria regulations need to be monitored to avoid unfavorable dietary changes in employees.

There is a need for global public health strategies to effectively curb the ever-growing global diabetes population. This longitudinal ecological study was conducted to elucidate the country-specific trends of the age-standardised prevalence of type 2 diabetes mellitus (T2DM) and their association with socioeconomic, lifestyle and health indicators. Data pertaining to the age-standardised prevalence of T2DM (rates per 100 000) and socioeconomic, lifestyle and health indicators were obtained from several international databases. Data available from 1990 to 2017 for 139 countries with populations of 1 million or greater were analysed, followed by estimation of slopes for T2DM prevalence in each country. The longitudinal association between T2DM and the standardised variables of socioeconomic, lifestyle and health indicators was fitted using a generalised linear mixed-effects model with random intercept for each country and random slope for year. The country-specific age-standardised prevalence of T2DM decreased significantly in 9 countries, remained unchanged in 11 countries and increased significantly in 119 countries. The estimated standardised effect of age-standardised education for T2DM was the largest at −524.5 (SE; 109.9), followed by −514.8 (SE; 95.6) for physical activity and 398.8 (SE; 45.8) for body mass index (BMI) (P < 0.0001 for all). The factors largely associated with global T2DM prevalence and trends were years of education, followed by physical activity and BMI. This study also provides basic resources for examining public health approaches to curb the increase in global T2DM prevalence.

In previous observational studies, the association between coffee intake and risk of cardiovascular disease has reversed from positive to negative over time. This long-term international ecological study examined whether the association between coffee intake and mortality and incidence rates of ischemic heart disease (IHD) changed between 1990 and 2018 using multiple coherent data. We obtained data on coffee intake per capita, IHD mortality and incidence rates per 100,000 population, and socioeconomic and lifestyle indicators for each country from various publicly available databases. We integrated and analyzed data from 147 countries with populations of ≥ 1 million. We employed a linear mixed model analysis to assess the association between coffee intake and IHD mortality and incidence rates by year. The mean global coffee intake increased (p < 0.001), whereas IHD mortality (p < 0.001) and incidence (p = 0.073) decreased. In all models, the interaction between coffee intake and year showed a significant inverse association for IHD mortality and incidence rates (p < 0.001 for all). The country-level association between coffee intake and IHD mortality and incidence rates between 1990 and 2018 was stronger in the negative direction.

The relationship between egg consumption and ischemic heart disease (IHD) remains controversial as there is still no clear answer regarding the relationship, with research limited to a few geographical regions. In the current study, we conducted a longitudinal analysis of the association between egg intake and IHD incidence (IHDi) and mortality (IHDd) using 28 years of international data from 1990 to 2018. Egg intake (g/day/capita) by country was obtained from the Global Dietary Database. Age-standard IHDi and IHDd rates per 100,000 subjects in each country were obtained from the 2019 Global Burden of Disease database. The analysis included a total of 142 countries with populations of at least one million, for which all data were available from 1990 to 2018. Eggs are consumed worldwide, and regional differences in consumption are also shown. Utilizing IHDi and IHDd as objective variables and egg intake as an explanatory variable, the analysis was conducted using linear mixed models, which controlled for inter- and intra-country variation from year to year. The results showed a significant negative association between egg intake, and IHDi (−0.253 ± 0.117, p < 0.05) and IHDd (−0.359 ± 0.137, p < 0.05). The analysis was carried out using R 4.0.5. The results suggest that adequate egg intake might suppress IHDi and IHDd on a global scale.

The effects of the regular consumption of soy, barley, and green tea in a real-life setting are unclear. This longitudinal observational study showed the associations of their intake with cardiometabolic health when employees freely selected these foods in the workplace cafeteria of an industrial company in Japan. The consumption was objectively assessed by an electronic purchase system using integrated circuit chip-equipped tableware and personal identification cards. The associations between the cumulative number of servings of each food during the 12 weeks prior to a health examination and changes in cardiometabolic measurements were examined among Japanese male workers (n = 890). Higher total intake of soy products was associated with significant lower levels in low-density lipoprotein cholesterol. Higher total intake of rice with barley was marginally associated with lower levels in systolic blood pressure and glycated hemoglobin. These associations were attenuated after adjustment for the baseline values of the dependent variables. Serving soy and barley products in the workplace cafeteria possibly promotes real-life benefits to employees’ cardiometabolic health.