In recent articles, we have discussed heart disease and cholesterol levels in women. We have also touched on the need for treatment based on cholesterol numbers and how sometimes this treatment can be over-prescribed if good analysis of cholesterol numbers is not done. In general, a good diet will include a combination of the three food types with every meal and snack: protein, carbohydrates, and fat. About 30 percent of your caloric intake should be fat, as this helps maintain your body processes, reduces your overall blood sugar level and insulin stimulation, and furnishes nutrients for your body to use in the production of hormones and other useful body chemicals.
Much research has been done regarding the ability of fats to either improve your health or make it worse. For example, studies reveal that total overall fat intake and high vegetable oil intake is associated with a higher cancer risk than with animal fat. In other words, when there is more natural saturated fat in the diet, the cancer risk is lower than if so-called healthy vegetable fat intake is high.
Vegetable fat is partially or poly-unsaturated, but is chemically treated to prevent spoilage. In its raw form as an omega-6 fatty acid, it can be healthy in limited quantities. However, in order to store this fat without it going rancid, it has to be hydrogenated. In chemical terms, hydrogenation implies that the “open spaces” (double-bonds) are saturated with hydrogen ions, which make it an artificially saturated fat. There is a difference between real saturated (animal) fat and hydrogenated saturated vegetable oil. Hydrogenated fat and trans-fat are definitely unhealthy for you and should be avoided, whereas saturated animal fat in reasonable quantities is healthier.
In our culture, the problem is that we eat too much partially hydrogenated vegetable oil, which is included in everything from salad dressings, baked goods, and snacks to the whole gamut of processed foods. One by-product of altering poly-unsaturated fat into hydrogenated fat is that some of it becomes trans-fat. Trans-fats are dangerous because they attach to cell walls and interfere with the movement of nutrients through these cell walls. A trans-fat has the same chemical compound as hydrogenated fat molecules, but it is a molecular “mirror image” of that and is just different enough that the body doesn’t know what to do with it.
Research at the University of Maryland showed that consumption of trans-fatty acids and partially hydrogenated acids increased the risk of heart disease, cancer, and diabetes; decreased immunity; and caused poor reproduction and obesity. Interestingly, the consumption of trans-fatty acids lowers HDL (healthy) cholesterol and raises LDL (bad) cholesterol by a significant amount. A study at Harvard University that included 85,000 women over a long term showed there was a significant relationship between trans-fatty acids and heart disease. The same is true about the development of cancer in people who eat partially hydrogenated fats. Trans-fats also decrease red blood cells’ response to insulin and thereby create an undesirable effect in diabetics. Trans-fats also significantly affect the immune system by lowering the efficiency of the B-cell (immune) response.
Monounsaturated fatty acids are chemically different and only have one double-bond linkage. This fat is usually healthy and occurs in nature as olive oil, avocado, and canola oil. Canola oil is genetically-modified rapeseed oil and was developed in Canada (Can + oil = Canola). When Dr. Ansel Keyes did the original studies on saturated fat intake and heart disease in 1958, he claimed that “partially hydrogenated vegetable oils with their trans-fatty acids were the culprits in heart disease.” The edible oils industry (which sells hydrogenated vegetable oil) was very quick to squelch that information and shifted the emphasis over to natural “saturated” fat which included meats, tropical oils (coconut oil), and dairy fats. I was recently shopping in the grocery store and noticed so many items that were “no-fat” or “low-fat.” I could not find plain Greek yogurt that had not had all of the fat extracted from it. This is not good because fat helps stabilize the body’s management of blood sugar and insulin, which is very important for our total body function.
It’s not difficult to relate this to your blood cholesterol levels and to the development of heart disease, cancer, and immune problems. Cholesterol is an oil and won’t mix with water, and so it travels in the bloodstream with protein particles that “carry it” and help it move about. HDL helps remove cholesterol from the body by transporting it to the liver whereas LDL does not aid in the transportation of cholesterol, but deposits it onto the vessel wall.
There is a very sensitive mechanism in your body for determining what the LDL cholesterol level will be. In familial hypercholesterolemia or excessive blood cholesterol levels, a mutant gene is responsible for the absence of LDL receptors, which then prevents the body from controlling its levels of cholesterol. Very high cholesterol levels leads to heart attacks even in the young. The cholesterol/HDL ratio is more indicative of cardiovascular disease than the total cholesterol (total cholesterol is HDL plus LDL totals). The ratio of these two is what is important, and if your cholesterol is 250 while HDL is 60, you are at an average risk for cardiac disease. So, you can divide your HDL into your total cholesterol and note that if the number is 5 or less, you are at an average or lower risk for heart disease. If you are at average or low risk for heart disease, you can improve your risk level by exercise, aspirin, and fish oil.
To increase HDL, performing aerobic exercise, cessation of smoking, avoiding passive smoke exposure, and reducing your weight can be effective. Decreasing LDL can be immediately accomplished by eliminating foods that contain hydrogenated fat, including baked goods and salad dressings, and by adding dietary fiber to your diet, increasing aerobic exercise, and taking niacin as a supplement. In general, you can improve your cholesterol levels and ratios with diet and exercise. However, people with familial high cholesterol cannot do this and must rely on statins to keep their blood cholesterol levels down to a less dangerous point.
So, improve your levels of HDL and LDL and avoid having to take powerful drugs such as statins, which may not help and may cause side effects. Also, you may eat saturated animal fat (bacon), tropical oils (coconut oil), or monounsaturated fat (olive oil). As usual, the more processed the food is that you eat, the less healthy it is for you.
Dr. Carraway is the director of the Plastic & Cosmetic Surgery Center of EVMS. Call 757-557-0300 for more information.