Saturated fats have been vilified as being the cause of heart disease, some cancers, and the obesity epidemic. Although heart disease and cancer were rare before 1920, the incidences of these diseases have increased dramatically since then. By as early as 1950, heart disease was the leading killer of Americans. However, contrary to what one would expect if the saturated fat/heart disease hypothesis were true, the consumption of animal fat between 1910 and 1970 DECREASED by 21% and the consumption of butter DECREASED from eighteen pounds per person per year to only four, according to the research of Sally Fallon and Mary Enig. Furthermore, over that same time span the consumption of refined vegetable oils much of it consumed as partially hydrogenated or trans fat, INCREASED by 400%, and the consumption of sugar and processed foods INCREASED by 60%. Current Canadian 2006 data (thank you Chris Williams!) suggest that those trends are continuing, with a continued decrease in the consumption of high saturated- fat foods like full-fat milks, eggs and red meat between 1970 and 2006. Since 1981, butter consumption (a saturated fat) has decreased by a third, while the consumption of salad oil (refined and therefore rancid polyunsaturated vegetable oils) has more than tripled. Shortening consumption (a trans fat) has remained relatively constant. So considering the continued decline in saturated fat consumption, blaming heart disease on saturated fat makes no sense (see this study published in the Lancet). To fully understand how it is possible that we find ourselves in this position where we are being told to eat refined polyunsaturated vegetable oils which are disease-causing and avoid saturated fats which are health promoting, read The Oiling of America by Mary Enig, PhD, fats and oils researcher, and Sally Fallon. The insight into the politics of food is scary.
All fats and oils are made up of a mixture of saturated, mono and polyunsaturated fatty acids. Calling animal fats "saturated fats" is very misleading, as many animal fats are actually more than 50% unsaturated, and chicken fat is actually 70% unsaturated. If a fat were completely saturated it would be very solid with the consistency of hard wax. For example, beef fat or tallow is made up of about 50% saturated fatty acids (25% palmitic acid, 22% stearic acid and others), 40% monounsaturated fatty acids (oleic acid, the main fatty acid in olive oil), and the balance polyunsaturated fatty acids (linoleic and linolenic, the ratio depending on the diet of the cattle).
Saturated fatty acids are critical to maintaining the structure and rigidity of our cells by making cell membranes out of phospholipids and cholesterol, and they act as enzyme and hormone regulators thereby playing an integral role in cell messaging. When the body is fooled and incorporates trans fats into the cell membrane instead of saturated fats, cell messaging no longer works, which is one of the reasons trans fats are so dangerous.
Saturated fats are necessary for calcium to be incorporated into our bones, so no-fat or skim milk won't work as a calcium source, unless you eat some saturated fat in your meal. Saturated fats are needed to boost immune function, and to build a healthy nervous system and digestive tract. Saturated fats are the base material out of which the body makes cholesterol, which is the precursor to such critical hormones as vitamin D, cortisol, testosterone, estrogen and progesterone, as well as bile acids which are necessary for the digestion of fats. Fats also are needed as carriers for the fat soluble vitamins (the antioxidant vitamins), like vitamin A, E, D, K, and a low fat diet can lead to deficiencies in these nutrients. Saturated fats are also needed to be able to utilize omega 3 fatty acids easily. Breast milk is high in saturated fat for a reason - it is vital for the healthy development of the baby! Does it make sense that saturated fats which are vital for a baby are suddenly poison for an adult?
Fat is also needed to feel satisfied after a meal. Mary Enig says in her book Know Your Fats: The Complete Primer For Understanding the Nutrition of Fats, Oils, and Cholesterol that "as a result of the presence of fat in the small intestine, special hormones are produced that prevent hunger contractions. ... Too much fat in the diet and the loss of weight is thwarted; too little and the hunger pangs play havoc with good intentions and usually lead to overeating carbohydrates."
Saturated fatty acids can be broken down into three groups - short chain, medium chain and long chain. The short and medium chain saturated fatty acids don't turn into body fat unless consumed in very large quantities, but rather are utilized immediately by the body for energy. Therefore fats that contain more short to medium chain fatty acids have less calories than the same amount of longer chain fatty acids. According to Mary Enig, in her book Know Your Fats: the Complete Primer for Understanding the Nutrition of Fats, Oils and Cholesterol, a pound of coconut oil has 100 kilocalories less than a pound of soybean oil. And yes, butter has less calories than margarine, although not much less.
If you are eating high quality fats, such as pasture fed, non-medicated, organic eggs, dairy, poultry, and meat, you are doing your body good. If you are eating conventionally raised poultry and meat, it is a good idea to cut off the fat, as the medications, hormones and pesticides consumed by the animal will be concentrated in the fat, which will in turn be concentrated in your fat. Cook only with pasture-fed organic butter, ghee, tallow or chicken fat, or organic coconut oil, or unrefined or cold pressed extra virgin olive oil (low to medium temperatures only), as these fats are stable and won't oxidize and go rancid when heated. To find out what ratio of fat, protein and carbohydrates are appropriate for you according to your own personal biochemistry, get yourself metabolically typed at Healthexcel, and receive a food list of appropriate foods for you. Some people require more quality fats to be healthy than others.
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