Raw Pacific or Atlantic halibut meat is 80% water and 19% protein, with negligible fat and no carbohydrates (table). In a 100-gram (3 1⁄2-ounce) reference amount, raw halibut contains rich content (20% of more of the daily value) of protein, selenium (65% DV), phosphorus (34% DV), vitamin D (32% DV), and several B vitamins: niacin, vitamin B6, and vitamin B12 (42-46% DV). Cooked halibut meat – presumably through the resulting dehydration– has relatively increased protein content and reduced B vitamin content (per 100 grams), while magnesium, phosphorus, and selenium are rich in content. Halibut is the common name for two flatfish in the genus hippoglossus from the family of right-eye flounders and, in some regions, and less commonly, other species of large flatfish.