A Review of Studies Listed on the Forum (to 2002) re - Fat, Diet, and Cholesterol
A Review of Diet, Fat, and Cholesterol Research: 25 Points.
Those who have heart disease generally but not always have high blood cholesterol. It is therefore theorized that high cholesterol causes heart disease. This is called a correlation. A correlation is an observation where when something increases, something else increases (a positive correlation) or when something increases, something else decreases (a negative correlation).
An example of how correlations don't necessarily prove anything is: In the last 100 years there has been an increase in global warming. And in the last 100 years women's shoe sizes have gotten bigger.
Does this show that global warming causes women's feet to get bigger?
So does high cholesterol cause heart disease? Just because many people have high cholesterol that also have heart disease doesn't prove this. Heart disease could cause high cholesterol. Or else high cholesterol could be a normal state for some people and heart disease could be caused by some other factor that causes cholesterol to clog the arteries. This is not a speculative statement as there exist at least two theories of heart disease that may make cholesterol an insignificant factor in heart disease: the homocysteine theory and the C-reactive protein theory.(1, 2)
1. Total serum cholesterol has proven not to be a strong determinant of cardiovascular risk.(3, 4)
2. HDL ratio has been proven to be a better standard to assess cardiovascular risk. What can you eat to raise HDL? Only one thing: fat.(5) All fats raise HDL but saturated fats raise HDL the most.(6)
3. The saturated fats except stearic acid do raise total serum cholesterol levels as shown in controlled and epidemiological studies.(7, 8, 9, 19, 33) This is insignificant if total cholesterol has little to do with heart disease.
4. If you have high cholesterol in most cases there is no need to avoid red meat. This is because only 30% of fats in red meat are composed of the saturated fats that raise cholesterol. What are the other 70%? Stearic acid which has a neutral effect on cholesterol comprises about 15%.(10, 19) About 50% is monounsaturated fat (like olive oil) which does not raise total cholesterol levels but raises HDL the good cholesterol.(25) And the remainder is polyunsaturated fat which lowers total cholesterol levels while raising HDL.(11) One study shows that lean red meat is equal to eating lean white meat.(12) So how do they test whether saturated fats raise cholesterol if red meat has so much of the other fats? One study used tropical oils.(9) Others have used liquid cholesterol products. When a natural diet is used, calculations are made according to percentage of each fat in each product, then elevation of cholesterol is apportioned accordingly.
5. It is beneficial that some saturated fats can raise cholesterol because if blood cholesterol gets too low, people get depressed, commit suicide or die of cancer.(13, 14, 15)
6. Studies are inconsistent regarding saturated fat. In one epidemiological study the more saturated fat one ate, the lower their serum cholesterol was.(16) In another study, saturated fats in the diet were high, but serum cholesterol levels were low.(17) Because the results of studies lack consistancy as regards to saturated fats in the diet, there must be some attenuating affect of saturated fats that negates the rise in total serum cholesterol.(19)
7. It is over-simplifying to name one villain, "saturated fat", as the culprit in heart disease especially when the results of studies on saturated fat are contradictory, inconclusive, and ambiguous at best. There are other factors that influence heart disease including but not limited to high glycemic carbohydrate intake, homocysteine, C-reactive protein, oxidative stress, smoking, and exercise to name just a few.(45) A meta-analysis of research to date states, "Despite decades of effort and many thousands of people randomized, there is still only limited and inconclusive evidence of the effects of modification of total, saturated, monounsaturated, or polyunsaturated fats on cardiovascular morbidity and mortality."(4)
8. In most people, however, if saturated fat raises their blood cholesterol it is probably not an important risk factor for heart disease as HDL is raised along with total cholesterol. It is also important to note that although LDL is raised too, it has been shown that there are two different types of LDL and saturated fats raise the good kind of LDL.(18) Also avoiding saturated fat may not be an important deterrent of heart disease because saturated fat is never alone in natural animal products but accompanied by monounsaturated (olive-oil-type-fats). Therefore, the combination of fats in animal products keep cholesterol levels where they should be which accounts for them not being a significant risk factor.(19)
9. Fat intake in the diet should not be decreased.(20, 19)
10. Protein with 80% from animal products which includes saturated fats lessens risk of heart disease.(21, 22)
11. Lowering saturated fats and cholesterol in the diet lowers HDL and decreases secretion of the good APO A-1 cholesterol.(23, 24)
12. Replacing saturated fats in the diet with carbohydrates is bad for your serum cholesterol and bad in general for your heart disease risk and mortality.(25, 26, 27, 28, 29, 30) Carbohydrates are not an essential nutrient in the diet.(31) Carbohydrates increase C-reactive protein thereby increasing risk of heart disease.(32)
13. Some nations that eat a high amount of fats and animal products [Crete(33, 34, 3) and Spain(35)] have less heart disease than nations who eat a little fat. Total fat in the diet is not an indicator.(3, 20)
14. Dietary cholesterol has little impact on total blood cholesterol.(36) Dietary cholesterol does not increase risk for heart disease or stroke.(37) Two-thirds of the population show no change in serum cholesterol levels from intake of cholesterol.(38) Dietary cholesterol accounts for a minimum amount of cholesterol produced by the body. The liver produces most cholesterol in the body. Eating cholesterol down-regulates your body's production of cholesterol.(39)
15. Many people with low cholesterol levels die of heart disease. One article stated: "Indeed, high cholesterol levels alone could only predict at most half of all heart attacks."(2)
16. Many people with exceptionally elevated levels of cholesterol never have a heart attack.(2)
17. Researchers say if a person, group of people or nation has higher serum cholesterol that they are at greater risk for heart disease. Croatia and Japan have high cholesterol but low heart disease.(40, 41) But considering that many people have high cholesterol and do not have heart disease and many with low cholesterol do have heart disease, then this may not be a valid marker of risk.(2)
18. Once the rise in HDL is factored in, studies have shown that saturated fats are less of a risk factor for heart disease than carbohydrate.(19, 42, 43)
19. A lot of people with heart disease have high triglycerides. High triglycerides are a risk factor for heart disease.(44, 45) Eating fat, any kind of fat, lowers triglycerides.(19, 46)
20. The American Heart Association has recommended that people with low HDL go on a diet high in unsaturated fat rather than replacing fat with carbohydrate.(47)
21. Saturated fats do not increase risk of diabetes.(48) The American Diabetes Association has recently recommended a high monounsaturated fat diet to those with diabetes.(49)
22. The American Heart Association says high glycemic carbohydrates are linked to heart disease.(50)
23. The American Heart Association says Americans should eat a 30% fat diet with not less than 15% fat.(47) The American Heart Association says diets less than 15% fat can be dangerous.(51) Ironically, Americans do not know this so they try to eat 0% fat and are ruining their health. However, these guidelines limiting fat intake to 30% do not appear to have support of the studies shown here.
24. Fats are not the cause of obesity.(52, 53) Studies have shown that diets high in fat and low in carbohydrate cause a person to lose weight.(54) High fat foods like nuts decrease risk of heart disease.(55)
25. Another important consideration is what our bodies were meant to eat. For the last 2.5 million years man has evolved as a hunter/gatherer with emphasis on carnivore-hunter. In the past hundred years man may have evolved a higher consciousness and may want to be vegetarian, but our bodies are genetically still 99.8% Paleolithic man and as such require meat. The leading experts on Paleolithic Nutrition say that man has eaten mostly animal products (likely over 50%) for most of his existence on earth.(56, 57, 58) Another important factor in evolution was man's development of a larger brain vs. body size. The only way this could have happened was with a nutrient dense source. The accepted explanation is "The Expensive Tissue Hypothesis" which states that meat and fat were that source.(59) These studies show that during man's entire history on earth fat intake would have exceeded both carbohydrate and protein intake. Grains are a foreign product in human evolution. For 99.9% of man's existence on earth, man did not eat grain. In fact, man is the only primate to eat cereal grains.(60) Therefore, trying to force our bodies to accept some form of higher consciousness by trying not to eat animal products would be a foreign diet to our system causing an unbalance and malnutrition in ways that science cannot even predict. Imbalance in the human body is the cause of all disease. When the body is perfectly balanced it is disease-free. Imbalance causes cancer, heart disease, autoimmune disease, and death. In other words, man's so-called recent "higher consciousness" is killing him.
Therefore, fat in the diet has never been the problem. Avoiding fat is the problem.
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7 Pai T, Yeh YY Stearic acid unlike shorter-chain saturated fatty acids is poorly utilized for triacylglycerol synthesis and beta-oxidation in cultured rat hepatocytes. Lipids 1996 Feb;31(2):159-64.
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Last edited by Voyajer : Mon, Aug-05-02 at 00:13.