Cross-sectional relationship of reported fatigue to obesity, diet, and physical activity: results from the third national health and nutrition examination survey.

STUDY
OBJECTIVES: Reported daytime fatigue may be influenced by modifiable risk factors. We hypothesized that daytime fatigue is associated with less-favorable lifestyle factors, including high body mass index, higher intake of dietary fat, and limited physical activity.
DESIGN: Cross-sectional analysis.
SETTING: Population-based survey. PARTICIPANTS: Participants aged 20 to 59 years in the Third National Health and Nutrition Examination Survey.
INTERVENTIONS: None. MEASUREMENTS AND
RESULTS: We examined relationships between responses to the question, "Right now would you say you are feeling energetic, fresh, average, tired or exhausted?" and body mass index, waist circumference, leisure time physical activity, and macronutrient intake. Analyses included only people who reported getting their usual amount of sleep the night before the evaluation and controlled for age, sex, and ethnicity; 5.6%, 14.6%, 58.3%, 19.5%, and 2.0% reported that they felt "energetic," "fresh," "average," "tire d," and "ex hausted" respectively. There was a U-shaped association across the categories of fatigue for physical activity, body mass index, and waist circumference, with the healthiest lifestyle factors being associated with reporting feeling "fresh." Relative to the fresh group, average, tired and exhausted participants were 1.6, 1.9, and 3.8 times more likely to report insufficient physical activity, all statistically different from the fresh group. This pattern was also observed for body mass index and waist circumference and persisted after adjustment for covariates and exclusion of individuals with depression.
CONCLUSIONS: In adults aged 20 to 59 years in the United States, self-reported fatigue is associated with higher body mass index, higher waist circumference, and a reduced likelihood of getting recommended levels of physical activity.