Cholesterol is a lipid, or a naturally occurring fatty molecule such as oil, wax, and fat, found in all animal tissue within the cell membrane. It is transported throughout the body by the circulatory system and is insoluble in blood, meaning it does not break down. As a result, it must be transported within particles called lipoproteins. Cholesterol tends to congregate in areas of the body that either synthesize the molecule or have densely packed cells, such as the liver, brain, and spinal cord. Most of our cholesterol comes from dietary sources through animal products; however, even plants and some fungi contain the lipid, and our bodies can utilize these sources as well.
Although the general belief is that too much cholesterol in the body is bad, it is actually required for many biochemical processes and the production and use of many hormones. What is not generally known is that there are five types of cholesterol, with two of the five playing the starring roles in our bodies: low-density lipoprotein (LDL) and high-density lipoprotein (HDL), while the other three play supporting roles that only a biochemist would understand or get excited about.
Understanding the Roles of LDL and HDL Cholesterol
High levels of low-density lipoproteins (LDL) are associated with atherosclerosis—the formation of plaque or fatty deposits in the vascular system. This leads to restrictions, or in severe cases, complete blockage of blood flow. The outcome is a heart attack or stroke, depending on which of the two organs—either the heart or the brain—is slowly suffocated.
On the other hand, high-density lipoproteins (HDL) actually help lower the levels and concentration of LDLs in the circulatory system. So, part of the treatment for high cholesterol is not only lowering the intake of LDLs but also increasing the consumption of high-density lipoproteins.
Low-density lipoproteins are most often found in animal products or products high in animal fat. The rule of thumb is that if the fat is solid at room temperature—such as lard, butter, cream, milk, eggs, red meat, and even chocolate—avoid it. These fats are usually classified as saturated fats, and they are bad for more reasons than just cholesterol levels. Avoid, avoid, avoid!
High-density lipoproteins are most often found in unsaturated fats, such as those in nuts, some vegetables and vegetable oils, olives, peanuts, and canola oil. These fats remain in liquid form at room temperature. Although they contain the same amount of calories per gram as saturated fats, they contribute to an increase in your waistline, not in your risk of suffering a heart attack or stroke.
The other source of HDLs is through essential fatty acids (EFAs) found in polyunsaturated fats. These fats are the lipids our bodies use to metabolize hormones, and since our bodies cannot produce this cholesterol, it must come from our food instead. The king of the EFAs is Omega-3, found in fatty fish such as salmon, mackerel, halibut, sardines, trout, herring, and tuna, as well as walnuts, leafy green vegetables, flaxseed, flaxseed oil, and canola oil.
Omega-3 EFAs increase the levels of high-density lipoproteins within the circulatory system, helping to break up ‘bad’ cholesterol or LDLs from cells and atheroma formations (the plaque that leads to atherosclerosis).
Unfortunately, the balance between ‘good’ HDLs and ‘bad’ LDLs is genetic. If your parents suffered from high cholesterol, there’s a good chance you’ll need to watch your saturated fat intake as you age. Many medications are available to help lower cholesterol levels for those with this genetic predisposition, but the best treatment is prevention. Early recognition and the avoidance of foods high in low-density lipoproteins, while increasing the intake of HDLs and foods rich in Omega-3 EFAs, can significantly reduce this risk.
If you exercise daily, control your weight, and increase your intake of healthy fats while lowering bad fats, there is a good chance you will live a long, healthy life free from heart disease and long-term illness. Choose salmon over beef, opt for Omega-3 fortified eggs if you must have eggs, and enjoy a spinach salad with roasted walnuts for lunch at least once a week—your heart will thank you for it!
