Most of the chemicals in your body and in your food are safe, but when many chemicals in your body and foods are oxidized and converted to their oxidized forms they become harmful. Cholesterol is pure and safe for arteries. Cholesterol in foods that was thought to cause heart attacks is actually safe, and even functions as an antioxidant that protects your arteries.
If you are deficient in vitamins B12, pyridoxine or folic acid, large amounts of homocysteine can build up in your bloodstream to convert your LDL cholesterol to oxidized LDL cholesterol, also known as oxycholesterol. Oxycholesterol damages arteries and can cause strokes and heart attacks. One way to increase your risk for a heart attack is to eat a diet that is low in folic acid, pyridoxine or vitamin B12, causing homocysteine to build up which converts cholesterol to oxycholestreol. However, taking B12, folic acid and pyridoxine vitamin pills has not been shown to prevent heart attacks in people with high levels of homocysteine (The New England Journal of Medicine, 354 (15): 1567–77). That is one of the reasons you should eat whole grains, beans, nuts and other seeds, to provide these three vitamins and other important nutrients from the foods you eat.
You also increase your risk for a heart attack by eating oxidized fats or cholesterol. The oils in vegetables such as corn and olive oil are primarily polyunsaturated fats that help to prevent heart attacks, but when you cook meats, chickens, diary products, eggs or fish by any method that does not add water, you convert the oils and fats to oxidized forms that can cause heart attacks. Almost all fried foods are oxidized, since frying at high temperatures converts fats to oxidized fats.
The oils in plants are healthful, but when they are removed from plants they become rancid.when exposed to air (oxygen), heat or light. Unfortunately, one way food manufacturers avoid rancid (spoiled) oils is to convert the healthful polyunsaturated vegetable oils to the unhealthful partially hydrogenated oils (trans fats), an oxidized form that can cause heart attacks. You should avoid foods made with partially hydrogenated oils. These oils are being removed from our food supply, but it is still a good idea to check the list of ingredients on cookies, baked goods, prepared frozen foods and other processed foods. If you see the words “partially hydrogenated,” pick another brand.
Put all of this information together, and try to eat foods as close to the way nature gives them to you as possible. Use whole grains instead of bakery goods, pastas and other foods made from flour. Eat vegetables, seeds and nuts for their oils instead of the oils that are extracted from them. Avoid sugars that are extracted from plants and added to cereals, soft drinks and other foods. Do not eat anything that contains partially hydrogenated fats. Avoid highly processed foods as much as possible. Eat rich sources of omega-3 fatty acids for their heart-protecting anti-inflammatory properties, including whole grains, beans, seeds, nuts and deep water fish.