Cholesterol, a waxy substance, is made by the liver or obtained from the food we eat. Cholesterol is found in every cell and is essential for many functions in the body, including the manufacture of hormones and fat-soluble vitamins.
Cholesterol is carried around the bloodstream by lipoproteins. Low density lipoproteins, or LDL cholesterol, carries the cholesterol from the liver to the bloodstream. LDL cholesterol is often referred to as bad cholesterol, explains the Mayo Clinic; if you have too much circulating in the body, it can stick to artery walls and cause them to become narrow, contributing to coronary artery disease. High density lipoproteins, or HDL cholesterol, takes excess cholesterol back to the liver and so is referred to as good cholesterol.
Patients with high cholesterol levels should consult a doctor before making any dietary changes.
Soluble Fiber
According to the Mayo Clinic, oat bran and other sources of soluble fiber such as apples, pears, kidney beans, prunes and barley may help decrease the amount of cholesterol absorbed into the bloodstream.
In a study published in a 1991 issue of "The American Journal of Clinical Nutrition," researchers studied the effect of oat bran on cholesterol levels. The team found that after 21 days, patients who had been eating oat bran had lower LDL cholesterol levels. HDL cholesterol levels where not changed.
The Mayo Clinic recommends eating 5 to 10 grams of soluble fiber a day.
Trans Fats
According to the American Heart Association, trans fats can raise LDL cholesterol levels. Trans fats, explains the Mayo Clinic, are made when hydrogen is added to vegetable oil, a process called hydrogenation. Manufacturers use trans fats to increase the shelf life of food.
Foods that may contain trans fats include doughnuts, cookies, cakes, french fries, margarine and crackers. Food that contains shortening or partially hydrogenated vegetable oil will contain trans fats, explains the Mayo Clinic.
The American Heart Association recommends getting no more than 1 percent of your total daily calories from trans fats.
Flaxseeds
Flaxseeds, or linseeds, are small brown seeds that are derived from the flax plant. Flaxseeds are a good source of fiber and a rich source of alpha-linolenic acid, an omega-3 essential fatty acid. Alpha-linolenic acid can be converted into the long-chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which are found in oily fish such as salmon and herring. According to the University of Maryland, omega-3 fatty acids, also called polyunsaturated fatty acids, are essential to human health for growth, development and brain function, and may help to reduce the risk of heart disease. Omega-3 essential fatty acids have to be obtained in the diet, as they can't be made in the body.
A study published in a 1999 issue of the "American Journal of Clinical Nutrition" examined the effect of flaxseeds on cholesterol levels. The team found that 20 grams of flaxseeds over a three-week period were effective in lowering LDL cholesterol.
The Mayo Clinic recommends grinding flaxseeds and sprinkling them over cereal or mixing them into yogurt.
References
- Mayo Clinic: High Cholesterol
- Mayo Clinic: High Cholesterol: Top 5 Foods to Lower Your Numbers
- "The American Journal of Clinical Nutrition"; Lipid responses of hypocholesterolemic men to oat-bran and wheat-bran intake: Anderson JW, Gilinsky NH, Deakins DA, et al; 1991
- American Heart Association: Know your fats
- Mayo Clinic: High Cholesterol: Trans Fat Is Double Trouble for Your Heart
