GOOD CHOLESTEROL, BAD CHOLESTEROL
(What You Should Have, What You Should Not)
Our body needs cholesterol in order to perform its functions. Cholesterol – a whitish, waxy substance – has essential functions and among them are: being an important component of cell membranes, providing myelin sheath to nerve fibers, production of steroid hormones, production of bile acids and synthesis of vitamin D. About eighty percent of our cholesterol is produced naturally by the liver; about twenty percent comes from the dietary intake. However, too much of cholesterol – whether produced by the body or from the diet – is also harmful.
Excess cholesterol, over time, builds plaques inside the arteries (condition is known as atherosclerosis). This build-up narrows the lumen of the blood vessels, hence, decreases blood flow. Further, rupturing of plaques leads to clot formation which blocks the arteries. The decreased blood flow to the heart increases the risk of heart attack, while the decreased blood flow to the brain increases the risk of stroke. Hypercholesterolemia (increased cholesterol in the blood) may not show symptoms, therefore it helps to have regular lipid profile check.
Risk factors for high cholesterol are : men ages 45 and up, women ages 55 and up, obesity and inactivity, diabetes, and family history.
A lipid profile examines the level of total cholesterol, LDL (low-density-lipoprotein) cholesterol or “bad” cholesterol, HDL (high-density-lipoprotein) cholesterol or “good” cholesterol, and triglycerides (blood fats). Target normal values are: below 200 mg/dL for total cholesterol; below 100 mg/dL for low-density-lipoprotein (LDL) cholesterol (“bad cholesterol”); not less than 40 mg/dL for high-density-lipoprotein (HDL) cholesterol (“good cholesterol”); and below 150 mg/dL for triglycerides. Total cholesterol/HDL ratio of 3.5 or below is considered ideal.
For individuals with very high risk of heart disease, an LDL level below 70 mg/dL should be aimed.
The Good Cholesterol
Cholesterol is carried by proteins called lipoproteins in the blood. The high-density lipoprotein, being of higher molecular weight, is able to bring the low-density lipoprotein to the liver, where cholesterol is eliminated. This means, therefore, that the more high-density lipoprotein the body has, the more low-density lipoprotein (“bad” cholesterol) will be eliminated. Thus, HDL is termed as good cholesterol.
An increased HDL minimizes the risk of heart disease.
Dietary sources for increasing good cholesterol are monosaturated fats (olive oil, peanut oil and canola oil are good sources) and polyunsaturated fats (from cereal and whole grain products; also fats from nuts, seeds and vegetables, and fats from fishes, such as salmon, tuna, herring or mackerel). A diet of fish at least two times a week is recommended.
Monounsaturated fats and polyunsaturated fats should, however, still be taken in moderate amounts because of the high calorie content.
The Bad Cholesterol
The bad cholesterol gets its name because since it is carried by low-density lipoprotein, it does not manage to bring itself to the liver and thus it easily builds up in the arteries. Bad cholesterol causes atherosclerosis, which in most cases can affect oxygen flow to the heart brought about by the narrowing of the lumen of the arteries.
A high LDL increases the risk of heart attack and stroke.
To minimize bad cholesterol, choose lean meat instead of regular meat; limit saturated fats (from meat, poultry skin, butter and dairy products); and avoid trans fats (which are found in most margarines and in commercially manufactured foods such as pastries and processed foods).
THE TEST
Checking for lipid profile involves taking blood sample from the patient. Blood is taken following 9 to 12 hours of overnight fasting (without food, liquid or medication). The blood sample obtained is then checked for total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides, and total cholesterol/HDL ratio, a number which is the best marker in estimating the risk of cardiovascular disease brought by atherosclerosis.
Total cholesterol refers to the total amount of LDL, HDL, VLDL (very low-density lipoprotein) and chylomicrons in the blood. VLDLs carry triglycerides in the bloodstream, and are later converted to LDL. Triglycerides, on the other hand, are linked to increased risk of heart disease and heart attacks.
It is important to have a cholesterol check at least once every 5 years.
Exercise
A 30-minute exercise (or two 15-minute exercises) fives times a week is helpful. Exercise need not be strenuous; brisk walking is also a good form of exercise.
Aerobic exercises can help lower LDL cholesterol and increase HDL cholesterol.
High-Fiber Foods
Eating high-fiber foods, such as whole grain, fruits and vegetables, legumes and nuts, is also recommended, as they lower the LDL cholesterol levels.
Smoking
Smoking should be avoided. When there are plaques build-up by high cholesterol, smoking worsens the situation by narrowing the blood vessels. In addition, smoking has been shown to lower the HDL cholesterol levels.
Alcohol
Moderate alcohol use has been linked to higher HDL cholesterol levels. Moderation in alcohol consumption means not more than one drink per day for women or not more than two drinks per day for men. However, consumption is not recommended for those who have not started drinking alcohol.
Blood Pressure
Fatty build-ups in the blood could lead to increased blood pressure, which could damage the arteries. It helps to check one’s blood pressure regularly to avoid complications. Normal blood pressure is less than 120/80.
Medications
In many cases, increased production of LDL cholesterol (“bad” cholesterol) is hereditary. A healthy diet and exercise will not be enough, and cholesterol-lowering medications are needed. In such case, a physician should be consulted since every individual has specific needs and conditions, for the medications or combination of medications to be effective. Some of the drugs need to be taken with caution and close monitoring, such as through liver function tests, due to their side effects.
(References: Americanheart.org, MayoClinic.com, WebMD.com, Cholesterol-and-health.com, Controlling Cholesterol the Natural Way)