Microbe-rich foods, high folate levels help alleviate fatigue in ageing adults

Eating microbe-rich foods and high circulating concentrations of bioactive folate (5-MTHF) are associated with lower fatigue in middle aged and older adults, with folate sufficiency seemingly augmenting the fatigue-reducing effects of live-microbe foods, according to a study.

Researchers conducted a cross-sectional analysis of 14,376 adults aged ≥40 years who participated in the National Health and Nutrition Examination Survey 2011–2023.

Fatigue was assessed using the Patient Health Questionnaire fatigue item and categorized as none/low or moderate/severe. Data on dietary intake of live-microbe foods were obtained from two 24-h recalls and classified as low, medium, or high. Total serum concentrations folate and its metabolites, including 5-MTHF, were measured.

A total of 2,500 participants (16.3 percent) reported moderate/severe fatigue. Those with vs without fatigue were more likely to be female and had higher rates of obesity and chronic conditions such as cardiovascular disease, chronic obstructive pulmonary disorder, and diabetes. Furthermore, the fatigue group had lower diet quality, total energy intake, and total folate intake.

There were 15 percent of participants who reported no intake of live-microbe foods. High vs low live-microbe intake was associated with 40-percent reduced odds of moderate/severe fatigue (odds ratio [OR], 0.60, 95 percent confidence interval [CI], 0.46–0.79). Similarly, higher serum 5-MTHF levels were associated with lower odds of moderate/severe fatigue (OR, 0.85, 95 percent CI, 0.73–0.98).

In stratified analyses, high live-microbe intake was associated with between 38-percent and 65-percent lower odds of moderate/severe fatigue only among adults with higher levels of 5-MTHF. This association was not observed among those with lower 5-MTHF levels.

The findings support a nutrient–microbe pathway relevant to healthy ageing and warrant further investigation.