The cardiac diet is a heart-healthy diet high in plant foods -- fruits, vegetables, legumes, nuts and seeds -- and restricted in cholesterol, sodium, sugar and fat -- particularly saturated and trans fat. You may also include low-fat dairy, lean poultry and fish on a cardiac diet. If you have heart disease, eating a cardiac diet can help prevent or delay your heart disease from worsening. If you do not have heart disease, eating a cardiac diet can help prevent heart disease.

The Power of Plant Foods

Plant foods provide fiber, plant sterols and stanols and phytochemicals. Fiber and plant sterols and stanols can lower cholesterol absorption in your body. Phytochemicals are antioxidant nutrients abundant in plant foods. According to researchers of a review study published in 2012 in "Current Medicinal Chemistry," phytochemicals can protect you from heart disease because they prevent high cholesterol and stroke.

Control Your Cholesterol

Eating a cardiac diet can help keep good HDL cholesterol up and bad LDL cholesterol down in your body. Limit your intake of saturated and trans fat and dietary cholesterol as they can increase your bad cholesterol. Saturated fat and dietary cholesterol come from meat and poultry fat and skin, egg yolk and full-fat dairy products. Trans fat is hydrogenated oil found in processed foods including margarine, shortening, fast foods, packaged foods and bakery items such as cakes and cookies.

Switch It Up

According to Harvard University, consuming polyunsaturated fats found in vegetable oils such as safflower, soybean, and corn oil; in walnuts; and in fish such as salmon and mackerel can actually help prevent and treat heart disease. Replace saturated and trans fats with polyunsaturated and monounsaturated fat, another type of good fat that is found in nuts, avocados, and canola, peanut and olive oil.

Shake Away From Salt

The American Heart Association recommends consuming no more than 2,400 milligrams of sodium per day but states the desirable amount of sodium for a cardiac diet is no more than 1,500 milligrams per day. Salt is sodium chloride. Sodium is in most packaged foods. Reduce the amount of salt you add to your fresh foods and the amount of packaged foods you eat and read nutrition facts labels for lower sodium.

Pick Your Pigment

Fruits and vegetables are naturally low in sodium, cholesterol and saturated and trans fats. Harvard University recommends consuming 25 to 35 grams of fiber daily. Researchers of a study published in "The American Journal of Clinical Nutrition" in 2003 suggest that combining different phytochemicals allows for the most health benefit. University of Michigan Health System suggests choosing different colors of fruits and vegetables as different phytochemicals give them their pigments. It lists spinach, kale, turnip greens, red cabbage, red grapes and cherries as choices that contain phytochemicals proven to reduce your risk of cardiovascular disease.

Go Nuts for Nuts, Legumes and Seeds

The American Heart Association recommends at least four servings of nuts, seeds and legumes per week -- unsalted and unsweetened, of course. Nuts, seeds and legumes are also good sources of plant sterols and stanols as well as fiber. One-half cup of cooked lentils or beans contains almost 8 grams of fiber.

Don't Skip Out on Whole Grains

Choose whole grains such as brown rice and whole-wheat bread rather than refined grains. Whole grains contain the germ and bran, where most of the nutrients, including 90 percent of the fiber, are. Refined grains have had the bran and germ removed in processing.