 saturated fat The much-maligned saturated fats-which generally people are advised to avoid-are not the cause of our modern diseases. In fact, they play many important roles in the body chemistry
Saturated fatty acids constitute at least 50% of the cell membranes. They are what gives our cells necessary stiffness and integrity.
They play a vital role in the health of our bones. For calcium to be effectively incorporated into the skeletal structure, at least 50% of the dietary fats should be saturated.(1)
They lower Lp(a), a substance in the blood that indicates proneness to heart disease.(2)They protect the liver from alcohol and other toxins, such as Tylenol.(3)
They enhance the immune system.(4)
They are needed for the proper utilization of essential fatty acids. Elongated omega-3 fatty acids are better retained in the tissues when the diet is rich in saturated fats. (5)
Saturated 18-carbon stearic acid and 16-carbon palmitic acid are the preferred foods for the heart, which is why the fat around the heart muscle is highly saturated.(6) The heart draws on this reserve of fat in times of stress.
Short- and medium-chain saturated fatty acids have important antimicrobial properties. They protect us against harmful microorganisms in the digestive tract.
The scientific evidence, honestly evaluated, does not support the assertion that "artery-clogging" saturated fats cause heart disease.(7) Actually, evaluation of the fat in artery clogs reveals that only about 26% is saturated. The rest is unsaturated, of which more than half is polyunsaturated.(8)
What About Cholesterol?
And what about cholesterol? Here, too, the public has been misinformed. Our blood vessels can become damaged in a number of ways-through irritations caused by free radicals or viruses, or because they are structurally weak-and when this happens, the body's natural healing substance steps in to repair the damage.
That substance is cholesterol. Cholesterol is a high-molecular-weight alcohol that is manufactured in the liver and in most human cells. Like saturated fats, the cholesterol we make and consume plays many vital roles:
Along with saturated fats, cholesterol in the cell membrane gives our cells necessary stiffness and stability. When the diet contains an excess of polyunsaturated fatty acids, these replace saturated fatty acids in the cell membrane, so that the cell walls actually become flabby.
When this happens, cholesterol from the blood is "driven" into the tissues to give them structural integrity. This is why serum cholesterol levels may go down temporarily when we replace saturated fats with polyunsaturated oils in the diet.(9)
Cholesterol acts as a precursor to vital corticosteroids, hormones that help us deal with stress and protect the body against heart disease and cancer; and to the sex hormones like androgen, testosterone, estrogen and progesterone.
Cholesterol is a precursor to vitamin D, a very important fat-soluble vitamin needed for healthy bones and nervous system, proper growth, mineral metabolism, muscle tone, insulin production, reproduction and immune system function.
The bile salts are made from cholesterol. Bile is vital for digestion and assimilation of fats in the diet.
Recent research shows that cholesterol acts as an antioxidant.(10) This is the likely explanation for the fact that cholesterol levels go up with age. As an antioxidant, cholesterol protects us against free radical damage that leads to heart disease and cancer.
Cholesterol is needed for proper function of serotonin receptors in the brain.(11) Serotonin is the body's natural "feel-good" chemical. Low cholesterol levels have been linked to aggressive and violent behavior, depression and suicidal tendencies.
Mother's milk is especially rich in cholesterol and contains a special enzyme that helps the baby utilize this nutrient. Babies and children need cholesterol-rich foods throughout their growing years to ensure proper development of the brain and nervous system.
Dietary cholesterol plays an important role in maintaining the health of the intestinal wall.(12) This is why low-cholesterol vegetarian diets can lead to leaky gut syndrome and other intestinal disorders.
Cholesterol is not the cause of heart disease but rather a potent antioxidant weapon against free radicals in the blood, and a repair substance that helps heal arterial damage (although the arterial plaques themselves contain very little cholesterol.)
However, like fats, cholesterol may be damaged by exposure to heat and oxygen. This damaged or oxidized cholesterol seems to promote both injury to the arterial cells as well as a pathological buildup of plaque in the arteries.(13) Damaged cholesterol is found in powdered eggs, in powdered milk (added to reduced-fat milks to give them body) and in meats and fats that have been heated to high temperatures in frying and other high-temperature processes.
High serum cholesterol levels often indicate that the body needs cholesterol to protect itself from high levels of altered, free-radical-containing fats. Just as a large police force is needed in a locality where crime occurs frequently, so cholesterol is needed in a poorly nourished body to protect the individual from a tendency to heart disease and cancer. Blaming coronary heart disease on cholesterol is like blaming the police for murder and theft in a high crime area.
Poor thyroid function (hypothyroidism) will often result in high cholesterol levels. When thyroid function is poor, usually due to a diet high in sugar and low in usable iodine, fat-soluble vitamins and other nutrients, the body floods the blood with cholesterol as an adaptive and protective mechanism, providing a superabundance of materials needed to heal tissues and produce protective steroids. Hypothyroid individuals are particularly susceptible to infections, heart disease and cancer.(14)
Bibliography
Enig, Mary G, PhD, Trans Fatty Acids in the Food Supply: A Comprehensive Report Covering 60 Years of Research, 2nd Edition, Enig Associates, Inc, Silver Spring, MD, 1995
Fallon, Sally with Mary G Enig, PhD; "Nourishing Traditions" 2nd ED, New Trends publishing Inc. , Washington DC, 2001
References
1. Watkins, B A, et al, "Importance of Vitamin E in Bone Formation and in Chrondrocyte Function" Purdue University, Lafayette, IN, AOCS Proceedings, 1996; Watkins, B A, and M F Seifert, "Food Lipids and Bone Health," Food Lipids and Health, R E McDonald and D B Min, eds, p 101, Marcel Dekker, Inc, New York, NY, 1996
2. Dahlen, G H, et al, J Intern Med, Nov 1998, 244(5):417-24; Khosla, P, and K C Hayes, J Am Coll Nutr, 1996, 15:325-339; Clevidence, B A, et al, Arterioscler Thromb Vasc Biol, 1997, 17:1657-1661
3. Nanji, A A, et al, Gastroenterology, Aug 1995, 109(2):547-54; Cha, Y S, and D S Sachan, J Am Coll Nutr, Aug 1994, 13(4):338-43; Hargrove, H L, et al, FASEB Journal, Meeting Abstracts, Mar 1999, #204.1, p A222.
4. Kabara, J J, The Pharmacological Effects of Lipids, The American Oil Chemists Society, Champaign, IL, 1978, 1-14; Cohen, L A, et al, J Natl Cancer Inst, 1986, 77:43
5. Garg, M L, et al, FASEB Journal, 1988, 2:4:A852; Oliart Ros, R M, et al, "Meeting Abstracts," AOCS Proceedings, May 1998, 7, Chicago, IL
6. Lawson, L D and F Kummerow, Lipids, 1979, 14:501-503; Garg, M L, Lipids, Apr 1989, 24(4):334-9
7. Ravnskov, U, J Clin Epidemiol, Jun 1998, 51:(6):443-460. See also http://home2.swipnet.se/~w-25775/
8. Felton, C V, et al, Lancet, 1994, 344:1195
9. Jones, P J, Am J Clin Nutr, Aug 1997, 66(2):438-46; Julias, A D, et al, J Nutr, Dec 1982, 112(12):2240-9
10. Cranton, E M, MD, and J P Frackelton, MD, Journal of Holistic Medicine, Spring/Summer 1984, 6-37
11. Engelberg, Hyman, Lancet, Mar 21, 1992, 339:727-728; Wood, W G, et al, Lipids, Mar 1999, 34(3):225-234
12. Alfin-Slater, R B, and L Aftergood, "Lipids," Modern Nutrition in Health and Disease, 6th ed, R S Goodhart and M E Shils, eds, Lea and Febiger, Philadelphia 1980, 134
13. Addis, Paul, Food and Nutrition News, March/April 1990, 62:2:7-10
14. Barnes, Broda, and L Galton, Hyprthyroidism, The Unsuspected Illness, 1976, T Y Crowell, New York, NY
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