as polyunsaturated oils, have replaced saturated fats in modern cooking.
Unfortunately, polyunsaturated oils are not stable; they are very prone to oxidation. These commercial vegetable oils are a recent addition to our diet since World War II, when manufacturers developed a process to make them shelf stable by using hydrogenation. Hydrogenating, or partially hydrogenating, these oils also makes them more solid (mimicking saturated fats) and useful for baking and deep-frying.
The most common polyunsaturated oils commercially processed in the U.S. containing trans fatty acids are soy, corn, cottonseed, rapeseed, and safflower; 90 percent of all margarines are made from soy oil and are loaded with trans fatty acids. Research shows that the processing of these polyunsaturated oils creates a whole new subclass of fats called trans fatty acids. These trans fats are not found in nature and are very toxic. Studies are now showing that trans fatty acids are linked to cardiovascular disease, diabetes, and cancer.
In January, 2004, Denmark became the first country in the world to ban the manufacture of trans fatty acids in its foods.11 In Europe, the consumption of trans fatty acids is decreasing. In the U.S., the FDA is requiring all food manufacturers to list trans fatty acids on the nutrition panel of their labels by the year 2006. Their website gives the following warning:
On July 9, 2003, FDA issued a regulation requiring manufacturers to list trans fatty acids, or trans fat, on the Nutrition Facts panel of foods and some dietary supplements. With this rule, consumers have more information to make healthier food choices that could lower their consumption of trans fat as part of a heart-healthy diet. Scientific reports have confirmed the relationship between trans fat and an increased risk of coronary heart disease. Food manufacturers have until Jan. 1, 2006, to list trans fat on the nutrition label. FDA estimates that by three years after that date, trans fat labeling will have prevented from 600 to 1,200 cases of coronary heart disease and 250 to 500 deaths each year.12
Which Fats Make Us Fat?
The fatty acid chains in polyunsaturated oils are long chain fatty acids (LCTs) while the fatty acid chains in coconut oil are medium chain fatty acids (MCTs). It has been known for a long time in the scientific community that LCTs tend to produce fat in the body, while MCTs promote weight loss. People in the animal feed business have known this truth for quite some time as well. If you feed animals vegetable oils, they put on weight and produce more meat. If you feed them coconut oil, they will be very lean and active.
In a study published in the American Journal of Clinical Nutrition, for example, rats were fed MCTs and LCTs for a period of six weeks. At the end of six weeks the rats were killed and dissected, and the total dissectible fat and fat cell size and number were determined. MCT-fed rats gained 15 percent less weight than LCT-fed controls. Their conclusion was that “overfeeding MCT diets results in decreased body fat related to increased metabolic rate and thermogenesis.”13
Polyunsaturated oils can also contribute to weight gain by suppressing thyroid functions, causing a lower metabolic rate that leads to packing on the pounds.
Dr. Ray Peat says:
Linoleic and linolenic acids, the “essential fatty acids,” and other polyunsaturated fatty acids, which are now fed to pigs to fatten them, in the form of com and soy beans, cause the animals’ fat to be chemically equivalent to vegetable oil. In the late 1940s, chemical toxins were used to suppress the thyroid function of pigs, to make them get fatter while consuming less food. When that was found to be carcinogenic, it was then found that corn and soy beans had the same anti-thyroid effect, causing the animals to be fattened at low cost. The animals’ fat becomes chemically similar to the fats in their food, causing it to be equally toxic, and equally fattening. 14
I have added coconut oil to my weight loss program, which is basically low carb, moderate protein, and reasonably high fat. I used this type of diet a few years ago and lost weight, but I “fell off the wagon” and put the weight back on. The major difference this time is that I have replaced all vegetable oils (corn, soy, canola, and so forth) with coconut oil and olive oil. When I eat a meal that has very lean protein, I take extra coconut oil. I have lost 58 pounds since December [that’s in just 8 months] with no exercise beyond a couple of walks per week. One positive side effect is that my resting heart rate has gone from 79 to 59.
I’m never hungry. In fact, I have to eat more than I feel like eating. Often times I could skip a meal, but I don’t do it because I don’t want my body to go into a starvation mode.
Perhaps the best part is that a lot of people are telling me I look younger.
Chuck
The Slimming Fats
Coconut oil, on the other hand, is nature’s richest source of MCTs, which increase metabolic rates and lead to weight loss. MCTs promote what is called thermogenesis. Thermogenesis increases the body’s metabolism, producing energy. There are many studies proving this in the scientific literature.
In 1989 a study was completed in the Department of Pediatrics, Vanderbilt University, Nashville, Tennessee. Ten male volunteers (ages 22 to 44) were overfed (150 percent of estimated energy requirement) liquid formula diets containing 40 percent fat as either MCTs or LCTs. Each patient was studied for one week on each diet in a double-blind, crossover design. The researchers noted the following results: “Our results demonstrate that excess dietary energy as MCT stimulates thermogenesis to a greater degree than does excess energy as LCT. This increased energy expenditure, most likely due to lipogenesis [formation of fatty acids] in the liver, provides evidence that excess energy derived from MCT is stored with a lesser efficiency than is excess energy derived from dietary LCT.”15
In another study recently conducted at the School of Dietetics and Human Nutrition, McGill University, Ste-Anne-de-Bellevue, Quebec, Canada, the effects of diets rich in medium-chain triglycerides (MCTs) or long-chain triglycerides (LCTs) on body composition, energy expenditure, substrate oxidation, subjective appetite, and ad libitum energy intake in overweight men was studied. Twenty-four healthy, overweight men with body mass indexes between 25 and 31 kg/m2 consumed diets rich in MCT or LCT for 28 days, each in a crossover randomized controlled trial. The researchers concluded: “Consumption of a diet rich in MCTs results in greater loss of AT compared with LCTs, perhaps due to increased energy expenditure and fat oxidation observed with MCT intake. Thus, MCTs may be considered as agents that aid in the prevention of obesity or potentially stimulate weight loss.”16
One “slimming fat” is a little known fatty acid called conjugated linoleic acid (CLA) found almost exclusively in ruminant animals and dairy fats. Research has shown that CLA tends to normalize body fat deposition. Without CLA, dietary fat tends to be stored in fat cells. Because CLA is negligible in most Western diets, we can have trouble controlling our weight. The body cannot produce CLA; we must get it from our food, the primary sources being beef and dairy products.
We can, however, make CLA from the trans-vaccenic acid that comes from milk fat.17 But most of us don’t eat much butter, cheese, or cream. Eating these products sparingly is a good idea because most of the animals in this country are not organically raised; indeed, they are injected with or fed antibiotics and growth hormones and pesticide sprayed food. Toxins tend to be stored in the fat more than the muscle, and therefore, eating a lot of animal fat from factory farm-raised animals isn’t the best idea.
We do tend to eat a lot of meat products in this country, so why are our CLA levels so low? People who study such things have found that the CLA content of these foods, if produced in the U.S., is low. CLA count started falling around 1950, about the same time that farmers began feeding cattle and dairy cows in feedlots, rather than allowing them to graze in pastures. It is eating grass that produces CLA in dairy cows and cattle.
In light of these facts, it is best to purchase grass-fed beef that has been raised organically (not injected with hormones and antibiotics), and to purchase dairy products from cows that are grass-fed and raised organically.
Best