5. Oily fish
Fish, such as salmon and tuna, are oily and rich in omega-3 fatty acids. They are the best source of youth and health. These fish have a wide range of omega-3 fatty acids. Eicosapentaenoic acid, or EPA, is one of them. This acid helps to produce and maintain collagen, hence your skin stays firm. Also it acts like an anti-inflammatory agent and helps to avoid skin cancer. Salmon and tuna are said to help against cardiovascular and other age-related diseases. The American Heart Association recommends eating oily fish two times per week. Salmon and tuna have a low concentration of mercury, so you should give your preference to them over any other.