Background Food choices on board merchant ships are limited and seafarers repeatedly described as being at high risk of developing overweight compared to the general population. Up to date, research has not distinguished whether seafarers gain weight on board or at home and whether eating habits differ in both settings.
Methods As part of the e-healthy ship project, cross-sectional data were collected in two different measurements. In the first investigation on board of three merchant ships of German shipping companies, differences in eating behaviour at home compared to on board ships were assessed for 18 Burmese, 26 Filipino and 20 European seafarers. In a second study, BMI, weight development and location of body weight change of 543 Filipino and 277 European seafarers were examined using an online questionnaire on 68 ships.
Results According to the board examinations, foods and beverages consumed on merchant ships varied widely from seafarers’ diets in their home country. Burmese, Filipino and European seafarers equally reported to consume more fruit (z = 4.95, p < .001, r = .62) and vegetables (z = 6.21, p < .001, r = .79), but less coke (z = −5.00, p < .001, r = .76) when at home. Furthermore, culturally different changes were found across all other foods and beverages. The online questionnaire revealed that 45.8% of seafarers were overweight (55.4% Europeans vs. 40.8% Filipinos, p < .001) and 9.8% obese. Moreover, a higher percentage of Europeans compared to Filipinos reported weight gain over the course of their professional career (50.2% vs. 40.7%, p = .007). A sub-analysis of seafarers with weight gain found that more Europeans than Filipinos gained weight at home (43.9% vs. 23.1%, p < .001).
Conclusions Both, home and working on board merchant ships, represent very different living environments which may affect seafarers’ lifestyle and eating habits in various ways and thus could favour or inhibit weight gain. From our results, it appears that the body weight and eating habits of Asian seafarers in particular are adversely affected by the working and living conditions on board. Further prospective studies are required to prove this hypothesis.