Most of us think of diet first when seeking to lower high cholesterol levels. The simple fact is that getting cholesterol levels back down to normal is much more a matter of how much you eat, rather than what you eat.
How the Liver Turns Excess Calories into Cholesterol
Only about 15 percent of the cholesterol used by the body is extracted from food. About 85 per cent of cholesterol circulating through the bloodstream is made by the liver, although every cell in the human body can make its own cholesterol from triglycerides.
Triglycerides are the the storage form of either excess sugar or excess fat. Making triglycerides enables fatty acids to dissolve in the watery environment of blood plasma, or stores away sugar in a form that does not have to burned for fuel right away. High triglycerides occur after overeating, or when diabetes disables the absorption of sugar, resulting in that sugar's conversion to its storage form.
The liver uses most of the triglycerides floating through the bloodstream to make LDL cholesterol. It does not make any difference where these triglycerides originate. When you eat more calories than your body needs, your cholesterol levels will slowly rise. That's why a lower-calorie Atkins diet sometimes results in lower cholesterol levels than a higher-calorie vegan diet.
The Example of the Egg
The egg is a good example of how foods that are high in cholesterol do not necessarily raise cholesterol. Over 20 years ago, the venerable New England Journal of Medicine reported a case study of a man who had eaten 20 to 30 hard-boiled eggs every day for over 15 years.
This 88-year-old man was under medical care for depression after his wife had died. He also had a diagnosis of mild Alzheimer's disease. The retirement community where he lived reported that he had an obsession about eating eggs, needing to eat hard-boiled eggs nearly constantly, all day long. His total cholesterol, LDL cholesterol, and trigylcerides, however, were in normal limits. A friend confirmed that the reports of his obsession about eating eggs were true.
How could eating nearly 150,000 eggs over a 15-year period not raise cholesterol? The doctor writing the case study report cited science showing that there are limits to how much cholesterol our bodies can absorb through the digestive tract. As long as this man did not start injecting eggs into his bloodstream, his liver simply compensated by making less cholesterol.
Subsequent studies found that eggs, like other high-cholesterol foods, do not raise cholesterol. It is the liver's use of excess calories that raises cholesterol. The way statin drugs like Lipitor and Zocor lower cholesterol levels is by deactivating the enzyme the liver uses to make both cholesterol and the heart-protective, oil-like substance ubiquinone, also known as coenzyme Q10.
No List of Foods That Help to Lower Cholesterol?
Since the amount of cholesterol the liver makes depends primarily on how much you eat, not what you eat, large changes in diet usually only result in small changes in cholesterol. There are two important exceptions to this rule. One is the better known cholesterol-lowering food oat bran. The other is a nutrient most people would not expect to lower cholesterol, taurine. No food choice in the American diet provides more taurine per ounce than the energy drink Red Bull.
The way oat bran lowers cholesterol is by stimulating the liver to make bile. This green solvent flows out of the liver into the gallbladder, and from the gallbladder into the colon. Bile emulsifies fats so they can be absorbed from food, but large amounts of bile cause cholesterol to be eliminated into the stool.
The active ingredient in oat bran is a naturally occurring complex sugar called beta-glucan. This sugar is damaged by industrial extrusion processes, so there is more benefit in an oat bran cereal than there is in an oat bran bar.
Another nutrient that lowers cholesterol is the amino acid taurine. This major constituent of meat, seafood, and the Red Bull Energy drink lowers LDL cholesterol levels by providing the building blocks for the enzyme that regulates LDL-capturing receptors in the liver. Modest consumption of meat and seafood in a low-calorie diet, ironically, lowers LDL cholesterol. Vegans can ensure they get enough taurine by taking an amino acid supplement. Because of the caffeine and sugar content, Red Bull is not a good choice for getting the taurine that lowers high cholesterol.
Sources
- Kern F Jr. Normal plasma cholesterol levels in a man who eats 25 eggs a day. New England Journal of Medicine. 1991 Mar 28;324(13):896-9.
- Yamori Y, Taguchi T, Hamada A, Kunimasa K, Mori H, Mori M. Taurine in health and diseases: consistent evidence from experimental and epidemiological studies. J Biomed Sci. 2010 Aug 24;17 Suppl 1:S6. Review.
Disclaimer: The information contained in this article is for educational purposes only and should not be used for diagnosis or to guide treatment without the opinion of a health professional. Any reader who is concerned about his or her health should contact a doctor for advice.
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