Prudent diet is associated with low sleepiness among short-haul truck drivers

The lifestyle of postindustrial society has undergone major shifts characterized by changes in demographic and epidemiologic profiles, eating habits, and job structures, with irregular working hours, particularly night shifts. The investigation of dietary patterns is of great importance for the discussion and devising of effective dietary strategies for shift and night workers in general, particularly in view of the increased sleepiness reported during night work.

We aimed to determine the association between dietary patterns of Brazilian truck drivers and sleepiness levels, according to work shift.

A cross-sectional study of 52 drivers (25 long haul and 27 short haul) at a freight company was carried out. This study entailed application of a structured questionnaire collecting sociodemographic, lifestyle, and nutritional status data. Assessment of dietary intake using a 24-h dietary recall and an evaluation of sleepiness by the Karolinska Sleepiness Scale were performed. The principal components of the diet were analyzed by factor analysis to derive dietary patterns. A linear mixed model was then applied to determine a model for sleepiness levels of the drivers as a function of dietary pattern, time of day, and work shift.

Three intake patterns were derived: traditional, prudent, and Western. Associations of time of day (F = 23.629, P < 0.01) and shift type (F = 42.218, P < 0.01) on sleepiness were found. An association between diet and sleepiness was also evident, where the prudent pattern was associated with low sleepiness among short-haul truck drivers (F = 3.865, P = 0.02).

The results of the present study revealed an association between dietary patterns and short-haul driving, in which the healthy pattern produced low sleepiness during the day. The sleepiness curve of long-haul drivers appears to have a flattening pattern, probably because of irregular working times.