Crew Health Advice: BMI at Sea - Why Weight Matters On World Obesity Day, public discussion often centres on health ashore. For seafarers, body weight carries additional importance.   Life at sea involves long contracts, watch systems, disrupted sleep, limited dietary flexibility and reduced access to ongoing medical follow-up. Over time, these realities can contribute to gradual weight gain. What is less widely appreciated is how strongly Body Mass Index (BMI) is linked to other medical conditions that affect long-term health and fitness to sail.   BMI is not simply a number recorded during a medical examination. It is closely associated with cardiovascular disease, type 2 diabetes, hypertension, abnormal cholesterol levels and sleep disorders. In remote maritime environments, where immediate hospital care may not be available, prevention becomes especially important.   Evidence from the Maritime Workforce   At the 17th International Symposium on Maritime Health (ISMH17), a large observational study examined BMI patterns in 4,625 Greek seafarers.   The data were collected through the Health4Crew digital health platform , analysing anonymised medical examination records across fleets. The study was authored by Laura Benzonana and Dr Christos Dimopoulos (in-house physician, Angelicoussis Group) and published in International Maritime Health (Benzonana & Dimopoulos, 2025).   The study showed that: The average BMI of male seafarers fell within the overweight range. Officers had higher average BMI than non-officers. BMI increased with age. Higher BMI was associated with a greater likelihood of abnormal cholesterol levels. Abnormal cholesterol is one of the principal contributors to coronary artery disease.   A Global Pattern   These findings are consistent with research conducted across different maritime populations.   A study of mixed-nationality merchant crews found overweight to be common onboard (Nittari et al., 2019