Your gastrointestinal tract, also known as your bowels, or gut, is involved in the process of digesting, absorbing and eliminating food. From top to bottom, your gastrointestinal tract runs 25 feet in length.

Vitamins come in two varieties: water soluble and fat soluble. Water soluble vitamins, such as B complex vitamins and vitamin C, dissolve in water and are excreted through the kidneys if you have excess amounts in your body.

Almonds share the same benefits as other types of nuts -- they’re high in nutrients and heart-healthy unsaturated fats that may lower your risk of cardiovascular disease.

Prunes are made from dehydrated plums and are sometimes called dried plums. Both purple and yellow plums can be used to make prunes, which are high in nutrients and dietary fiber. Prunes can be eaten dried as-is, although they are sometimes stewed to make a dessert or are processed into prune juice.

Salad greens -- the leafy green vegetables that are either too delicate for cooking or traditionally consumed raw -- are a common staple for calorie-conscious dieters and healthy eaters alike.

Whey is the liquid that remains during the cheese-making process. Whey powder is made from the filtered and dried liquid. Studies have tested the benefits of whey protein for muscle-building, weight loss and as a dietary supplement to combat diseases, such as diabetes.

Grapefruit can make a phenomenal bedtime snack when your stomach is rumbling just enough to keep you awake but not so much that you want to eat a full meal. Because it’s so light, refreshing and low in calories, a half grapefruit can keep your hunger at bay until morning comes without ruining any healthy diet plan.

Iron is one of the most vitally important nutrients in the diet. Not only is it essential for normal growth and development, healthy skin, bones and teeth and optimal immunity, but it also supplies body cells with the oxygen they need to produce energy.

Carbohydrates or ‘carbs’ are an energy source in food that comes from starch, sugar and cellulose. Carbohydrates provide vitamins, minerals, antioxidants and fiber in the diet. The current recommendations suggest 45 to 65 percent of daily calories come from these types of foods.

Psyllium consists of the indigestible seed husks of a plant native to India and Pakistan. The seed husks are a good source of soluble fiber, and thus act as a natural laxative. As such, they are also a popular ingredient in colon cleansing and detox regimens, and are also used as a binder in gluten-free baking.

Vitamin B12 is a water-soluble vitamin in the B-complex of vitamins. Most people obtain adequate vitamin B12 from the foods they eat, but some people still choose to supplement, or your doctor may recommend a supplement. Unlike some vitamins, vitamin B12 is measured in micrograms, not milligrams.

Advertisements touting pork as lean are accurate for some cuts, but remember this: They’re not talking about baby back ribs. To qualify as “lean,” pork must contain 10 grams or less of total fat per serving. Pork baby back ribs have nearly double that amount.