This study aimed to objectively evaluate the diet consumed in a workplace cafeteria to group Japanese workers according to vegetables and salt intake and estimate the association of these groups with changes in cardiometabolic measurements.

This longitudinal observational study estimated the food and nutrient intake of Japanese workers from data recorded in the cafeteria system of their workplace. The primary outcomes included cardiometabolic measures obtained via regular health check-ups conducted at the workplace. The participants were divided into four groups according to high or low vegetables and salt intake based on their respective medians and the association of each group with cardiometabolic measurement changes was estimated using robust regression with MM-estimation.

A Japanese automobile manufacturing factory.

The study included 1,140 men and women workers with available cafeteria and health check-up data.

An inverse marginal association was observed between changes in triglyceride levels and high vegetables and low salt intake (β: −9.93, 95% confidence interval [CI]: −20.45, 0.59, p: 0.065) with reference to low vegetables and high salt intake. This association was stronger in participants who used the cafeteria more frequently (>71 days; β: −13.55, 95% CI: −25.51, −1.60, p: 0.027).

The participants in the higher vegetables and lower salt intake group were more likely to exhibit decreased triglyceride levels. These findings encourage using workplace cafeteria meals to promote the health of workers.