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1:8:2003 |
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| Natural products to lower cholesterol levels - Don't forget niacin There are a number of specific natural medicines that effectively lower cholesterol levels. Since new ones come along all the time (see previous newsletter on Delta-tocotrienol - The 21st Century Vitamin E?) it is easy to forget just how impressive the results are with niacin. Before taking a look at the effects of niacin in lowering cholesterol levels, it is important to have an understanding of exactly what all the different forms of cholesterol represent. First of all, cholesterol is a natural substance made by the liver to serve several important body function including being the backbone for important hormones like estrogen, testosterone, and cortisone. Cholesterol travels from the liver and into your circulation by hitching a ride on protein molecules called low-density lipoprotein (LDL), often called "bad cholesterol." It is carried away from tissues and back to the liver aboard high-density lipoprotein (HDL) ("good" or "protective cholesterol"). Some people find it easier to remember the difference by labeling LDL "lousy" and HDL "healthy or happy." The more LDL you have, the more cholesterol is in circulation, and the greater your risk of heart disease. Currently, experts recommend that your total blood cholesterol level should be less than 200 mg/dl. The LDL level should be less than 130 mg/dl and the HDL level should be greater than 35 mg/dl. For every one percent drop in LDL levels, there's a two percent drop in the risk of heart attack. By the same token, for every one percent increase in HDL, the risk of heart attack drops three or four percent. The ratio of your total cholesterol to HDL and the ratio of LDL to HDL are clues that indicate whether cholesterol is being deposited into tissues or is being broken down and excreted. The ratio of total cholesterol to HDL should be no higher than 4.2, and the LDL-to HDL ratio should be no higher than 2.5. Another important lipoprotein to be aware of is a form of LDL called lipoprotein (a), or Lp(a). This form of LDL has an additional molecule of an adhesive protein called apolipoprotein. That protein makes the molecule much more likely to stick to the artery walls and cause damage. New research suggests that high Lp(a) levels constitute a separate risk factor for heart attack. For example, it appears that high Lp(a) levels are ten times more likely to cause heart disease than high LDL levels. Lp(a) levels lower than 20 mg/dl are associated with low risk of heart disease; levels between 20 and 40 mg/dl pose a moderate risk, and levels higher than 40 mg/dl are considered extremely risky. Niacin does more than lower cholesterol The cholesterol lowering activity of niacin was first described in the 1950s. It is now known that niacin does much more than lower total cholesterol. Specifically, niacin has been shown to lower LDL cholesterol, Lp(a) lipoprotein, triglyceride, and fibrinogen levels while simultaneously raising HDL cholesterol levels. Despite the fact that niacin has demonstrated better overall results in reducing risk factors for coronary heart disease compared with other cholesterol-lowering agents, physicians are often reluctant to prescribe niacin. The reason is a widespread perception that niacin is a difficult to work with because of the bothersome flushing of the skin. In addition, since niacin is a widely available "generic" agent, no pharmaceutical company stands to generate the huge profits that the other lipid-lowering agents have enjoyed. As a result, niacin does not benefit from the intensive advertising that focuses upon the "statin" drugs. Despite the advantages of niacin over other lipid-lowering drugs, it accounts for less than 10% of all cholesterol-lowering prescriptions. Several studies have compared niacin to standard lipid-lowering drugs including the statin drugs. These studies have shown significant advantages for niacin. For example, in one 26 week study patients were randomly assigned to receive treatment with either lovastatin (Mevacor) or niacin.1 The results are shown below: Lovastatin vs. Niacin in a 26-Week Study
These results indicate that while lovastatin produced a greater LDL cholesterol reduction, niacin provided better overall results despite the fact that fewer patients were able to tolerate a full dosage of niacin because of skin flushing. The percentage increase in HDL cholesterol, a more significant indicator for coronary heart disease, was dramatically in favor of niacin (33 vs. 7%). Equally as impressive was the percentage decrease in Lp(a) for niacin. While niacin produced a 35% reduction in Lp(a) lipoprotein levels, lovastatin did not produce any effect. Other studies have shown that niacin can lower Lp(a) levels by an average of 38%.2,3 The most recent comparative study involved niacin vs. atorvastatin (Lipitor).4 The average dosage was 3,000 mg with niacin and 80 mg for atorvastatin was used at 80 mg/day. The patients selected had abnormal particle size of LDL in that the molecules were small and dense - these LDL molecules are considerably more atherogenic than larger, less dense LDL. The patients selected also had low levels (less than 40%) of a specific fraction of HDL associated with a greater protective effect than HDL alone. Although atorvastatin reduced total LDL cholesterol levels substantially more than niacin, niacin was more effective in increasing LDL particle size and raising HDL and HDL2 than the atorvastatin. Table 1. The Effect of Atorvastatin (Lipitor) and Niacin on Lipid Profiles
While statin drugs are also gaining popularity as a prescription method to lower C-reactive protein (CRP) - a marker of inflammation and a risk factor for heart disease. It appears that the while majority of physicians appear to be aware of the effect of Lipitor and Pravachol on C-reactive protein they do not seem to be aware that natural products offer even greater activity. For example, vitamin E (800 IU daily) lowered C-reactive protein by 49% and niacin (1500 mg at night) lowered it by 20%, much more meaningful reductions than those seen with Pravachol and Lipitor.5,6 Because taking niacin at higher dosages (e.g., 3,000 mg or more) can impair glucose tolerance, many physicians have avoided niacin therapy in diabetics, but newer studies with slightly lower dosages (1,000 to 2000 mg) of niacin have not shown it to adversely effect blood sugar regulation.7 For example, during a 16-week, double-blind, placebo-controlled trial, 148 type 2 diabetes patients were randomized to placebo or 1000 or 1500 mg/d of niacin; in the niacin treated groups there was no significant loss in glycemic control and the favorable effects on blood lipids were still apparent.8 Other studies have actually shown hemoglobin A1C to drop indicating improvement in glycemic control.9 If you take a look at the most common blood lipid abnormality in type 2 diabetic patients it is elevated triglyceride levels, decreased HDL cholesterol levels, and a preponderance of smaller, denser LDL particles. Niacin has been shown to address all of these areas much more significantly than the statin or other lipid lowering drugs. However, one of the reasons that niacin may not be as popular as it should be is the bothersome side effect of skin flushing - kind of like a prickly, heat rash that typically occurs 20-30 minutes after the niacin is taken and disappears in about the same time frame. Other occasional side-effects of niacin include gastric irritation, nausea, and liver damage. To reduce the side effect of skin flushing you can use some of the newer time-released formulas including the prescription version Niaspan or take the niacin just before going to bed. Most people sleep right through the flushing reaction. Taking cholesterol lowering agents at night is best because most of the cholesterol manufactured by the liver happens at night. Another approach to reduce flushing is to use inositol hexaniacinate. This form of niacin has long been used in Europe to lower cholesterol levels and also to improve blood flow in intermittent claudication - a peripheral vascular disease that is quite common in diabetes. It yields slightly better clinical results than standard niacin, but is much better tolerated, in terms of both flushing and, more importantly, long-term side-effects.10 If you start out with trying inositol hexaniacinate and it does not work, try regular niacin. Our experience is that some people will only respond to the regular niacin. If regular niacin or inositol hexaniacinate is being used, start with a dose of 500 mg at night before going to bed for one week. Increase the dosage to 1,000 mg the next week and 1,500 mg the following week. Stay at the 1,500 mg dosage for two months before checking the response - dosage can be adjusted up or down depending upon the response. If you are using a time-release niacin product, like Niaspan, start out at the full dosage of 1,500 mg at night. Regardless of the form of niacin being used, I strongly recommend
periodic checking (minimum every 3 months) of cholesterol. A1C,
and liver function tests. Key References:
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