By Renata Trister, DO
Most people who are even a little bit concerned about their cholesterol know that there is a“good/Healthy cholesterol” – known as HDL, and a “bad/Lousy cholesterol” – known as LDL. Although, research shows that the higher the amount of HDL and the lower the amount of LDL in the blood, the less likely a person is to suffer a heart attack or stroke, the “causal” relationship between cholesterol and these illness has not been determined. Roughly one in six Americans with “unhealthy” cholesterol levels. In the past 15 years, prescriptions of cholesterol lowering medications has soared. In 2011, 260 million prescriptions were dispensed in US alone.
Scientific opinions differ on cholesterol issues, and there is contrary evidence to theories. Two major clinical trials in the past three years have greatly complicated the picture. The first study, from 2008, shows that lowering LDL levels does not always decrease the risk of having a heart attack. Similarly, results from the second study, show that raising HDL levels does not always translate into fewer heart attacks or strokes. These perplexing findings do not mean that people should stop taking their cholesterol medications. The results have, however, underscored the danger of indulging in a common logical shortcut – assuming that artificially producing normal test results in a patient is the same as conferring good health on that patient. For one thing, drugs typically do not mimic normal conditions perfectly. For another, heart attacks and strokes occur after a complex series of processes that may take years to unfold. Simply altering one of these processes does not necessarily fix the whole problem.
Understanding Cholesterol Testing and its Functions.
Cholesterol is a crucial building material in the body. It helps maintain the structure of cells and vessels, improving overall health and function in the body.
About 80% of cholesterol is produced in the body. Liver, brain and other cells produce cholesterol. About 20% of cholesterol comes from food.
The cholesterol screening test that is usually performed is a blood test called a lipid profile. Results of a lipid profile will come in the forms of numbers. The values of LDL, HDL, trigycerides and total cholesterol are measured.
There is no such thing as “bad cholesterol”.
HDL and LDL are actually proteins that carry cholesterol. Cholesterol can’t dissolve in the blood (like oil and water). It has to be transported to and from the cells by carriers called lipoproteins – HDL, LDL. These carriers have different and crucial functions, they are not “good” or “bad”. Low-density lipoprotein, or LDL carries cholesterol made in the liver to other tissues. The liver synthesizes cholesterol based on need. High-density lipoprotein, or HDL carries cholesterol from peripheral tissue back to the liver.
The following is a few vital functions of cholesterol:
– Cholesterol is a precursor to important sex hormones like testosterone, estrogen, androgen and progesterone. It is also a precursor to corticosteroids, hormones whose primary function is to protect the body against stress and disease.
– Used as an insulator around nerves, cholesterol is absolutely essential for brain function.
– Bile salts are made from cholesterol, adequate cholesterol is needed for proper digestion.
– Cholesterol is a precursor to vitamin D, an important nutrient which supports a healthy immune and nervous system, reproduction, insulin production and the metabolism of minerals.
– Serotonin receptors in the brain require cholesterol in order to function properly. Serotonin is an important neurotransmitter, low levels of serotonin are linked to depression.
Triglycerides make up about 95% of your body’s fat and are the chemical form in which most body fats exist. The fat produced from triglycerides is used for energy production, provides your body’s organs with insulation, and is a central component in the structure of cell membranes. Unused triglycerides are transferred to fat cells for storage. When energy is needed, hormones can cause the release of the stored fats. Excess triglycerides increase the risk of stroke, heart attacks, fatty liver, pancreatitis and obesity.
Since triglycerides are part of a serum lipid blood test, and lipids are fats circulating in the blood, most people assume high fat diets increase triglycerides. They are surprised to learn sugars, refined grains, and fruit sugars cause elevated triglycerides.
High blood sugar levels lead to high triglycerides levels. Sugars and refined grains stimulate insulin production. Insulin stimulates the liver to produce triglycerides. Triglycerides in the blood are not made from dietary fats but made in the liver from excess sugar, which has not been used for energy. Eating more calories than your body can use for energy contributes to higher triglycerides.
The LDL cholesterol is made in response to damage and stress. When blood vessels are damaged, LDL-carried cholesterol “patches up” the arterial lining with a buildup of fatty material, or atherosclerotic plaque. Much of the time the plaque stabilizes without creating too many immediate problems, but sometimes it bursts, triggering blood clots that lead to heart attacks and strokes if the clots prevent blood from delivering critical oxygen to heart or brain tissue. Without oxygen, the affected tissue dies.
People with high LDL levels may form arterial plaques that are more likely to burst. Some people develop extremely high LDL levels because of a genetic disease called familial hypercholesterolemia that severely limits their ability to clear cholesterol from their blood. They suffer heart attacks in their thirties or forties, which is several decades earlier than the average for the general population. On the positive side, those who maintain normal cholesterol levels (LDL less than 100 milligrams per deciliter of blood and HDL cholesterol levels greater than 40 mg/dL) throughout their life without medication are much less likely to suffer heart attacks or strokes.
A Shortcut ?
With all this evidence linking heart disease to cholesterol levels, it is no wonder that researchers in general and pharmaceutical companies in particular reached a fairly straightforward conclusion: anything – such as a medication – that reduces LDL levels and raises HDL levels must also reduce heart disease risk. By the 1980s the drug industry began marketing a whole family of cholesterol-lowering drugs called the statins, which work by blocking a liver enzyme that is essential for forming cholesterol. Clinical studies proved that statins do in fact reduce the number of heart attacks in people with high cholesterol. Might statins provide benefits unrelated to cholesterol reduction? There is some evidence that they also decrease inflammation. (When inflammation occurs in the arteries, it is thought to increase the risk of heart disease.) A 2008 study called the JUPITER trial tested statins in about 18,000 people with normal LDLs but elevated C-reactive protein, a measure of inflammation. Statins reduced the risks of heart attack and stroke. That led proponents to conclude that by working through an additional mechanism—lowering inflammation, not just LDL—statins were helping even people with normal LDL levels. Cholesterol lowering drugs also have anti-inflammatory properties Inflammation is strongly suspected of contributing to atherosclerosis.
To some extent, as long as the statins were working, few people worried too much about why they were helping. But statins are not for everyone. Some people cannot tolerate the drugs’ multiple side effects, including muscle pain and, more rarely, liver damage. Others cannot lower their LDL levels enough simply by taking a statin. In addition, at least one in five people whose LDL levels are well controlled by their medications still experience heart attacks or strokes.
Food and Lifestyle:
Elevated blood cholesterol may be a response to stress and injury (damage repair, cell formation, hormones production…). Trans fats, refined sugars, artificial sweeteners, industrial meats, genetically modified foods can cause total and LDL cholesterol rise because they stress and injure tissues. Therefore, diet and lifestyle changes can be very beneficial.
Weight loss. Even a modest amount of weight loss can lower cholesterol levels.
Reduce the amount of sugar and flour in your diet. Recent evidence indicates that added sugar – in the form of table sugar (sucrose) or high-fructose corn syrup – is probably a greater contributor to heart disease than is consumption of saturated fat. This suggests that the inflammatory hypothesis may in fact have more validity than the conventional lipid hypothesis, although the debate is far from settled. As a general rule, avoid processed sugars, particularly soft drinks and highly processed snack foods, which can cause rapid spikes and dips in blood sugar levels. The result can be overeating, obesity and heart disease.
Avoid trans-fatty acids.
These heart-damaging fats can reduce HDL (“good”) cholesterol levels and raise levels of LDL (“bad”) cholesterol. The tip-off that trans-fatty acids are present in foods is the listing of “partially hydrogenated oil” on a food’s ingredient list. Trans-fats are found in many brands of margarine and in most heavily processed foods, as well as in snack foods such as chips, crackers and cookies, and in the oils used to cook fast-food French fries, doughnuts and movie popcorn.
Decrease toxic load by eating fresh organic foods when possible.
Exercise. Daily aerobic exercise can help increase HDL levels.
Don’t smoke. Smoking itself is a risk factor for heart disease. It can also significantly lower HDL cholesterol.
Stress. Emotional stress may prompt the body to release fat into the bloodstream, raising cholesterol levels.