1 The right side of the heart receives oxygen-poor blood from body tissues and pumps it to the lungs where it picks up oxygen and gets rid of carbon dioxide. 2  The blood vessels that carry blood to and from the lungs form the pulmonary circuit.
According to the Dietary Guidelines for Americans 2015-2020, a healthy eating plan: 1  Emphasizes fruits, vegetables, whole grains, and fat-free or low-fat milk and milk products. 2  Includes lean meats, poultry, fish, beans, eggs, and nuts. 3  Is low in saturated fats, trans fats, cholesterol, salt (sodium), and added sugars.
Lean meat, poultry, fish, legumes, dairy, eggs, nuts, and seeds are good sources. The FDA says adults should eat 50 grams of protein a day. Pregnant and nursing women need more. Foods that have it provide nutrients like vitamins B6 and B12, both of which keep your immune system working like it should. Vitamin B6 comes in protein-rich foods like turkey and beans, as well as potatoes, spinach, and enriched cereal grains. Meats, milk, and fish also contain vitamin B12, a powerful immune booster. Minerals like selenium and zinc also keep your immune system going strong. These minerals are found in protein-rich foods like beans, nuts, meat, and poultry.