Energy expenditure, body composition, and nutrient adequacy in personnel of a Chilean Antarctic expedition: an occupational comparison

Background Antarctic expeditions expose personnel to extreme environmental conditions that may compromise nutritional status, energy metabolism, and body composition. This exploratory study characterized these parameters in Chilean Antarctic personnel and assessed dietary macro- and micronutrient adequacy. Methods Twenty participants (14 men, 6 women; median age 41 [IQR 35–46] years) deployed for at least 15 days to Escudero and Yelcho stations (November 2024–March 2025) were assessed before and after deployment. Resting metabolic rate (RMR) and respiratory quotient (RQ) were measured by indirect calorimetry, body composition by bioelectrical impedance analysis (BIA), handgrip strength by dynamometry, and dietary intake by 24-h recall compared with Dietary Reference Intakes. Solar radiation was obtained from the INACH sensor network. Results RMR, body composition, and handgrip strength did not change after the expedition. RQ showed a nominal increase (median 0.74 to 0.80) that was not significant after correction for multiple comparisons. At baseline, 45% of participants were obese and 65% had excess body fat. Energy, protein, and lipid intakes were close to reference values, whereas intakes of vitamin D (median 5% of the reference value; all participants below it), folate, fiber, vitamin C, and carbohydrate were below reference values. Daily solar radiation at Escudero had a median of 147 W/m 2 and fell by more than half between December and March. Conclusion Chilean Antarctic personnel showed a high risk of inadequate intake of several micronutrients, particularly vitamin D, together with a high prevalence of baseline adiposity. Because vitamin D status was not measured biochemically, these findings indicate risk rather than confirmed deficiency. They support biochemical monitoring, preventive vitamin D supplementation protocols, and improved food provisioning for Antarctic personnel.