- Seafarers' living conditions are much more difficult than on land; The cultural and spiritual life is very difficults as lacking information from the mainland, the mono sex-only micro-social environment, and stress wach keeping activities... are the causes of psychological stress; - Unbalanced diet, lack of green vegetables, fiber; excess of fat, protein, sugar, bad habits in daily life (100% of seafarers drink alcohol at different levels; 56.5% a seafarer smokes cigarette; 51.25% of a seafarer does not have any physical training on board.)