Nutrition can absolutely help relieve some of the mood problems that you have because of hormonal fluctuation during pregnancy. Try to avoid processed foods and refined carbohydrates, including sugar, as much as possible, because they cause blood sugar fluctuation and leads to mood swing. Try to include these nutrients in your meal – Omega 3 fatty acid, good carbs, vitamin B6, selenium and folic acid. Also make sure you get enough vitamin D and the easiest way is go outside, get 15 minutes of sunlight without any sunscreen. Some examples of good mood foods include cold-water fish, asparagus, turkey, sunflower seeds, walnut, pineapples and bananas.