Just how do we define cholesterol? Is it, like most people think, all totally bad and to be avoided in all forms? What types of foods is it found in and what roles does it play in our body? In terms of cholesterol management, what sort of dietary choices are the best, and just what are good cholesterol levels? Questions such as these and many others need to be understood by anyone trying to stay healthy while enjoying the modern American diet.
Cholesterol is a fat based substance that is produced in the body of all animals and that makes up part of the cell membrane. No plants produce cholesterol, but some plants produce oils that the body will turn into cholesterol, while other plants can help to clear cholesterol from the body. Now if cholesterol is so bad for us, why does our body produce it in the first place? There are three main functions of cholesterol in the human body, it helps the liver produce bile which is necessary for proper digestion, it is used by certain glands to produce needed steroids and hormones including sex hormones, and as already mentioned it is a major building block of cell membranes and structures. Without cholesterol, in small amounts, our bodies would not function and we would die. It is the "in small amounts" that is the important part of that last sentence. High cholesterol levels can mean major problems for the body. When the body has more than it needs, the excess can buildup on and clog blood vessels leading to atherosclerosis (hardening of the arteries) and an increased risk of stroke and heart damage.
So just what are good cholesterol levels and how are they measured? There are several different types of cholesterol in the body, LDL. HDL, chylomicrons, and VLDL. Cholesterol, being fat based, is an oily substance meaning in its raw state it will not mix with the water based blood fluids. The body gets around this by packaging cholesterol in molecules called lipoproteins that are covered by water soluble proteins. The different types of cholesterol are based on the ratios of these proteins to the lipoproteins. LDL or low density lipoproteins have a lower amount of proteins and a higher amount of the fatty lipoproteins. LDL is the type responsible for the buildup of deposits of cholesterol in the blood system, thus it is called "bad" cholesterol. HDL or high density lipoprotein has more protein molecules than lipoprotein ones and has been discovered to play a role in removing cholesterol deposits from the artery walls. It acts to transport LDL to the liver where it is removed from the body, making HDL the "good" cholesterol. Chylomicrons are cholesterol particles that are produced in the intestines and play a role in the digestion of foods. VLDL stands for very low density lipoproteins and will become LDL, making it another cholesterol type to avoid in the body. LDL, HDL, and VLDL are all produced in the liver in amounts determined by both genetics and diet.
Standard blood tests used for measuring levels of cholesterol, are based on the amounts of LDL, VLDL, and HDL in the blood after a fasting period. The total cholesterol number is a combination of the amounts of these three types of cholesterol and in adults can range from 120 to over 300 mg/dl with a level of 200 or more being considered high. Because of the different roles of LDL vs HDL, blood tests that show the levels of each type can be more revealing than a total cholesterol number. It is generally recommended that adults having a level of cholesterol exceeding 200 mg/dl should be retested to determine the good cholesterol levels vs the bad cholesterol levels. The USDA recommends keeping levels of LDL cholesterol below 100 and levels of HDL above 32 with levels of around 60 being excellent for the good cholesterol. It is important to remember that there are no magic numbers when it comes to cholesterol levels. Other health risk factors such as smoking, alcohol consumption, body weight, and a history of heart disease, all have to be taken into account along with cholesterol numbers before a person's risk for developing heart and circulatory problems can be accessed. One person may have a total cholesterol level of 212 with an HDL level of 52 and be at less risk of health problems than another person who has a total cholesterol level of 180 and an HDL level of only 20. It has been shown that people who follow a heavy exercise routine tend to have higher cholesterol levels mainly due to higher good cholesterol levels. One thing that can be said for the majority of people is that practicing cholesterol management and lowering cholesterol levels will definitely lower their risk of developing cornary heart problems and blocked arteries.