Cholesterol is perhaps the most misunderstood nutrient of all. Sure, the stats are overwhelming…
the CDC says:
- High blood cholesterol increases your risk of heart disease, the #1 cause of death in America.
- 71 million American adults (33.5%) have high low-density lipoprotein (LDL), or “bad,” cholesterol.
- Only 1 out of every 3 adults with high LDL cholesterol is managing the condition.
- Less than half of adults with high LDL cholesterol get treatment.
Let’s take the “scare” out of the statistics and really get clear on what cholesterol is, how it works in the body, and the most natural ways to lower cholesterol levels to optimal.
Blood Lipids and Cholesterol Defined
Blood lipids technically refer to fat particles circulating in the bloodstream. Conventionally, the definition is broader and refers to all fat particles in the blood, including particles in the blood that are combinations of lipids and protein, like cholesterol.
Cholesterol is the best-known blood lipid. Because cholesterol is a combination of lipid and protein, cholesterol-containing particles in the blood are called lipoproteins. These include high-density lipoprotein (HDL), low-density lipoprotein (LDL), and very-low-density lipoproteins (VLDL). The other primary form of fat in the blood is called triglyceride, which is three fatty acid molecules hooked together.
How Do the Blood Lipids Relate to Each Other?
The liver is the main site of fatty acid and cholesterol production. Fatty acids produced in the liver link together to form triglycerides. While triglycerides and cholesterol are made in the liver, the liver is not equipped to store much of either. Consequently, they are packaged with proteins and secreted into the blood as VLDL.
VLDL is the primary transporter of fat from the liver to the peripheral fat stores. The VLDL circulates in the blood to the fat cells, or adipose tissue (otherwise known as body fat).
Adipose tissue is the proper storage site for triglyceride. A larger amount of fat can be stored in adipose tissue. Although an excessive amount of triglyceride storage defines obesity, under normal conditions fat is stored in adipose tissue without any adverse effect.
The triglyceride in the VLDL is taken up by the adipose tissue thanks to a protein called lipoprotein lipase. This enzyme is not completely effective, though, and LDL are left as the result of incomplete clearance of the VLDL by the adipose tissue. The LDL in the blood circulate back to the liver, where they are either cleared from the blood or taken up by other cells in the body. This is the main route by which cholesterol is delivered to the tissues of the body.
A special receptor on the membranes of the liver and other tissues plays a key role in taking up the cholesterol from LDL. If the cholesterol in LDL is taken up by the liver it is metabolized and eliminated from the body, but cholesterol taken up by other tissues can remain and disrupt normal function.
HDL is often referred to as the “good” type of cholesterol because it serves primarily to clear LDL from the blood. The more HDL there is relative to LDL, the more rapidly cholesterol will be cleared by the liver and broken down and excreted. This is why it is common to test the LDL:HDL ratio.
Not all the triglycerides produced by the liver are excreted as VLDL—some can be secreted in the form of triglycerides directly into the blood. This is another way that fatty acids are transferred from the liver to adipose tissue for storage.
Normal values for blood lipids are as follows:
- LDL < 100 mg/dl
- HDL ≥ 40 mg/dl
- Triglycerides < 150 mg/ml
Functions of Lipids in the Body—They Aren’t All Bad!
When we have a physical exam, it is routine to have the concentrations of these blood lipids measured, and if the values are out of the normal range, treatment options are recommended. This gives us the very distinct feeling that the blood lipids are all bad.
While elevated levels of some of the blood lipids are indeed associated with bad health outcomes, let’s first consider some of the beneficial roles of blood lipids.
Cholesterol plays many roles in the body, including helping the body to produce certain hormones, vitamin D, and enzymes that help you digest food. Cell membranes are largely made up of lipids. Problems arise, however, when you have too much cholesterol and/or triglycerides. Excess is never a good thing.
Consequences of Abnormal Blood Lipids
LDL has the reputation of being the worst of the blood lipids. The cholesterol in LDL can accumulate and form plaques that stiffen your arteries. This condition is called atherosclerosis.
Cholesterol-rich plaques can clog the arteries, leaving less room for blood to circulate. Plaques can also rupture, which causes platelets to come to the site of rupture and form blood clots. If the clot is big enough, it can block blood flow. If this happens in a vessel supplying blood to the heart, it will cause a heart attack, and if it happens in a vessel supplying blood to the brain it will cause a stroke.
Triglycerides are also a risk factor for atherosclerosis and, therefore, heart attack and stroke. Recently physicians have been paying even more attention to an elevated triglyceride level because that is one of the factors that define metabolic syndrome. Triglyceride accumulation in the liver is a defining factor in metabolic disease. Metabolic syndrome is the precursor of diabetes, and diagnosis and treatment are critical to diabetes prevention.
Conventional Strategies to Lower LDL and Triglycerides
Statins are widely prescribed to lower LDL levels. These are usually effective, but not without side effects—most commonly, muscle pain—particularly in older individuals. In some cases, this muscle pain may be alleviated by taking another type of statin, or by taking a dietary supplement of CoQ10, as one of the side effects of statins is CoQ10 depletion. CoQ10 is important in producing energy.
There are other medications to help lower LDL levels, including cholesterol absorption inhibitors, fibrates, and niacin. Again, you may find that all of these have adverse side effects. Blocking fat absorption can lead to diarrhea, fibrates can impair normal liver function (especially in older individuals), and niacin can cause itching and flushing.
These additional medications may function together with statins to lower LDL effectively, but the numerous potential side effects make it worthwhile to also look to more natural ways to lower cholesterol.
Keep in mind that while these medications may help lower cholesterol, they usually do not affect triglyceride levels. Fibrates are the most effective prescription medication to lower triglycerides, but adverse effects on the liver limit the use of these drugs.
Natural Ways to Lower Cholesterol
The cholesterol myth is still holding strong: that you can lower cholesterol by cutting out cholesterol in the diet. This is a fallacy. Cholesterol in the blood is produced in the liver, not absorbed from digested food. The most recent dietary guidelines from the U.S. Department of Agriculture give the green light to eating eggs. Eggs used to be the poster child for avoiding dietary cholesterol, as the yolks are composed of cholesterol. Not anymore. Enjoy those omelets as you wish.
Certain dietary and lifestyle behaviors are associated with lowering cholesterol, but it should be noted that some of these are merely associations, and association does not prove cause and effect. Studies showing a significant effect of certain changes in diet or behavior may be occurring at the same time as other changes that are actually responsible for the observed response. So, let’s stick to approaches that have a physiological rational, if not a scientifically proven mechanism of action. These approaches are:
- Exercise is particularly valuable in raising HDL levels, which in turn lowers LDL.
- Losing weight may increase HDL, although may not impact LDL levels.
- Decreasing saturated fats and increasing menstruated fats in your diet. Although this recommendation seems to have good rational behind it, evidence that saturated fats cause increased LDL is still mostly theoretical.
- Increasing omega 3 fatty acid intake. While evidence is solid on this point, the effective dosage is hard to obtain from diet alone and will usually require a dietary supplement. Increased bruising and bleeding may be a side effect.
- Avoid trans fats, which increase LDL and lower HDL.
- Eating soluble fiber will promote “good” bacteria in the intestine that lower both LDL and VLDL.
Exciting New Findings!
Essential amino acids (EAAs) are the only required dietary macronutrient. They are involved as key components of all proteins in the body and play various physiological roles. EAAs are in all forms of dietary protein, so regardless of the nature of your diet, you consume at least some EAAs.
The exciting new findings are that consuming extra EAAs in the form of a nutritional supplement lowers liver and blood triglycerides as well as total cholesterol, LDL, and VLDL, whether taken alone or with phytosterols (cholesterol-like compounds in plants).
EAAs stimulate the synthesis of proteins involved in transporting lipids from the liver to peripheral fat, as well as the protein required for the clearance of fatty acids into adipose tissue for storage. Dose response studies have not been done, but successful reduction of blood and liver lipids was achieved with two doses of 11 grams of EAAs twice per day.
The great advantage of EAA supplements is that they are natural, and essential, components of our regular diet and pose no known risks of adverse responses. Not only can they can impart beneficial effects by themselves on blood and liver lipids, but they can also boost the effectiveness of statins. In addition to the positive influence EAAs have on blood lipids, they also have proven benefits for muscle health and physical function.