 [ Symptoms ] what vitamins are present in fish oil carrots are carrots but they contain vitamins as well what is in fish oil [ Disease ] the reason people take fish oil is for the type of fat it provides omega 3 fatty acids dha and epa most people do not get enough of these fats through diet unless they consume 2 servings of fatty fish such as salmon or tuna per week these type of fats are important for brain development in babies cardiovascular health and they play a role in brain related conditions such as adhd and dementia see this article for more information on fish oil