Cholesterol and Triglycerides

  As we age, almost all of us will encounter the subject of cholesterol and triglycerides.  Most of us have been tested at one time or another to measure the amount of these substances floating in our blood.  These tests are one way doctors monitor our metabolic health and tendencies toward arterial disease.

  Triglycerides are fatty materials that are measured in the blood along with cholesterol.  Much like LDL cholesterol, triglycerides can increase the risk of heart attack, stroke and artery hardening.  Triglycerides are usually very sensitive to dietary changes – heavy fat, starch or sugar can lead to high triglycerides in the blood.  Diabetes that is not well controlled causes the liver to turn excess sugars into triglycerides.  Triglycerides can also be genetically high, can increase if certain thyroid conditions are present, and may be elevated in women taking estrogens.  If triglyceride levels are near 1000 or more on blood tests, it may indicate a relatively rare pancreatic inflammation that can cause painful pancreatitis.  For people with existing artery narrowing due to cholesterol buildup or in people with diabetes over age 35, doctors recommend values under 150 for triglycerides on fasting blood tests.  Individuals with no risk factors will want to keep triglyceride scores under 200.  In some cases, just cutting back on sugar or starch portions, decreasing waist size slightly, and/or doing gentle daily exercises can help significantly lower  triglycerides on blood tests.  Using natural fish oils and/or niacin vitamins can also significantly lower triglyceride blood levels in some cases (niacin is best taken under a physician’s supervision).

  Cholesterol is a substance produced by the liver and used in cell membrane construction.   Although it is naturally produced by the body, it’s also present in foods we eat – most commonly in meat, poultry, fish and dairy products.  Cholesterol is found primarily in foods of animal origin, not in foods that come from plants.  Chemically speaking, cholesterol is a combination of lipid (fat) and steroid.  The liver not only produces cholesterol, but also regulates how much cholesterol is stored or released into the blood from the foods we eat.  The “total cholesterol” number measured on blood tests is broken into two kinds:

HDL = high density lipoprotein, considered “good” cholesterol
(remember it by “H = happy”)

LDL = low density lipoprotein, considered “bad” cholesterol
(remember it by “L = lousy”)

  Target numbers for a healthy cholesterol level depend on other risk factors a person may have for disease.   A healthy 35 year old without risk factors for coronary artery disease should aim for an LDL under 150 and HDL in the range of 65-75.  If an individual has other risk factors for arterial disease, the LDL target number will be even lower.  People with some cholesterol artery narrowing or diabetics who are above age 35 should have an LDL under 70. 

  Ideally, the goal is to keep good cholesterol levels high and bad cholesterol levels low.  Research has shown that keeping LDL (bad) cholesterol low reduces the risk of heart attack, stroke and hardening of the arteries. 

  HDL cholesterol is considered “good” because it actually can work as a mini vacuum cleaner, removing plaque from artery walls and disposing of it through the liver.  Those lucky individuals with high HDL cholesterol can most often attribute it to heredity.  Unfortunately a person’s HDL number is often hard to manipulate into a positive range simply by a change of eating habits or activity.  Increasing exercise and eating foods like oatmeal, soy, and fish high in omega-3 oils (or fish oil supplements) can have a mild positive effect on HDL levels for some people when combined with reducing animal fat in their diet.  Quitting smoking and vitamin niacin have also been shown to increase HDL. Regardless of your HDL number, slow daily exercise can help the HDL do its job of trying to clean out arteries naturally.  When bad cholesterol is high, the body lays some of it down in the arteries in the form of plaque.  Over time, the outside layer of this plaque develops a fibrous cap that acts like a protective shield.  After about 20 minutes of exercise, the artery wall relaxes and this hardened area is more able to be removed by the “vacuum cleaners” of HDL cholesterol.  Exercise makes the best conditions for what HDL you have to get in there and clean!

  The easier blood cholesterol number to change is LDL (bad cholesterol).  High LDL blood cholesterol is associated with increased risk of coronary heart disease and is therefore to be avoided.  Many individuals can bring their LDL and triglyceride numbers down by changing their diet and reducing their waist size.  The factors that affect blood cholesterol levels include what we eat, body weight, exercise, gender, age, diabetes, and heredity.  Some individuals have high LDL because of their diet and physical condition.  This group can impact and change their LDL cholesterol level simply by eating better, losing weight and/or exercising.  Other individuals have inherited a tendency toward high LDL cholesterol.  This group may have only a limited ability to change LDL levels by diet and exercise.  Medications are available to effectively reduce LDL cholesterol for most individuals.

  Your doctor monitors cholesterol levels carefully because they are an easy indicator of how much plaque your body may be laying down in the arteries.  Risk factors for hardening of the arteries (arterial sclerosis) include smoking, family history of cardio-vascular disease at 55 or younger, being sedentary, diabetes, high blood pressure, being overweight, and/or being a Type A personality (anxious, angry, driven, stressed).

  In some cases, individuals may have high cholesterol without accumulating plaque in the arteries.  If your cholesterol is high but you have no other risk factors for heart disease, it may be a good idea to investigate how much plaque is accumulating in your arteries by another means.  Other ways to check for hardening of the arteries include having a neck ultrasound or a CT scan called a “calcium score” that is now becoming affordable and commonly available.   For around $125 (most insurances aren’t paying for this yet) your doctor can order a quick CAT scan test that will see how much calcification has occurred in the arteries around your heart.  This is becoming a way to screen patients for hardening of the arteries earlier on in their life, before a heart event has ever occurred.

  In general, lowering bad cholesterol and triglycerides is managed through a healthy diet, controlling weight, exercising and working with your doctor if medication is needed.