Poor Cholesterol – always being deemed the “bad guy.” Although, the majority of people believe cholesterol is the devil, I’d like to give a more accurate analogy – six-year-old Jimmy. Jimmy’s the adorable, blonde-headed, blue-eyed, and well-behaved momma’s boy at a child’s birthday party. Little Jimmy can go from being the most precious innocent thing to an out-of-control terror after eating a big piece of birthday cake. Cholesterol is no more inherently bad than little Jimmy. Without cholesterol our bodies could not function properly and without Jimmy, his mom would be lost. But just like Jimmy, when cholesterol goes haywire from factors including genetic predispositions, diet, or lack of exercise, yes – cholesterol can be bad news. Although cholesterol has two faces, the general public typically only sees the bad face. With heart disease on the rise, obesity affecting 1 in 3 adults, and a broken food system it’s no wonder cholesterol gets caught in the middle of America’s health disputes.
What is Cholesterol?
Cholesterol or C27H46O, is a lipid which essentially is a fat molecule that contains hydrocarbons, are insoluble in water, and nonpolar molecules. Lipids include, fats, oils, vitamins, waxes, and steroid hormones, which are all essential to structure and function in the human body. Cholesterol is a waxy substance that is both naturally produced in the body (when there’s a low dietary intake of cholesterol) but normally acquired through an unrestricted diet, which directly inhibits the amount of cholesterol the body naturally produces. Interestingly, cholesterol cannot be sweated out during exercise or burned off like calories. (Facts About Cholesterol) Certainly, exercise can help with cholesterol management, but diet is the most effective and preventative way to maintain healthy cholesterol levels, of below 200 mg/dL. Foods high in saturated and trans fats, which includes most animal products like, egg yolks, meat, poultry, and full-fat dairy, are all high in cholesterol. Fruits and vegetables on the other hand contain very minimal cholesterol. High levels of cholesterol are also associated with commercial baked goods since they are processed with partially or fully-hydrogenated fats. Prescription drugs such as statins, bile acid sequestrants, fibrates, PCSK9 Inhibitors, and Ezetimibe are also commonly used to control high cholesterol levels. (Cholesterol, Lipoproteins and the Liver) WebMD considers a few dietary supplements to be somewhat beneficial for lowering bad cholesterol and triglyceride levels in the body. These include: fish oils or omega-3’s, psyllium (a fiber), soy protein or phytoestrogens, garlic, CoQ10, niacin, and red yeast rice. (Cholesterol Medicines: What to Know)
LDL – The Bad Twin
In the body, each cholesterol molecule must be bound to proteins called apoproteins, thereby allowing them to be soluble in water. At this point this cholesterol molecule is considered a lipoprotein. (Lipoproteins and Apoproteins) In metabolism, these lipoproteins lose, acquire, and exchange various lipids and proteins associated with the molecule, through various chemical interactions. Foods very high in fat usually lose their fat within the first few hours of consumption. (Lipoproteins and Apoproteins) These lipids are processed in the intestinal epithelia cells, are thrown into the blood stream, travel through the capillaries where they lose some fat, and then are taken up by the liver where they are synthesized and put back into the blood stream as high-cholesterol containing molecules. (Lipoproteins and Apoproteins) These high-cholesterol containing molecules are what define LDL, low-density lipoproteins, or “bad” cholesterol, which make up 60-75% of total blood cholesterol. (Lipoproteins and Apoproteins) LDL molecules are dense in fat, less dense in protein, and fairly stable molecules.
At normal levels of below 100 mg/dL, LDL molecules usually stay in the body for a few days until they are consumed by “cholesterol gobbling” cells in the body. This process is vital to the proper functioning of tissue cells to produce certain steroid hormones and uphold cell membrane integrity. (Cholesterol, Lipoproteins and the Liver) On the other hand, when LDL is present in the body at excessive levels, LDL molecules stay in circulation for longer periods of time and become susceptible to oxidation. Once oxidized, LDL is deposited as atherosclerosis plaques in arteries, commonly known as hardening of the arteries. This leads to numerous issues including stroke, blot clots, heart disease, and heart attacks. This is why LDL is considered “bad” cholesterol.
HDL – The Good Twin
Cholesterol is somewhat of a “multiple personality” chemical in the sense that there is “bad” cholesterol but also “good” cholesterol called high-density lipoproteins or HDL. The HDL precursor travels in the blood, picks up excess cholesterol, and uses this to synthesize mature HDL in the liver and small intestine. (Cholesterol, Lipoproteins and the Liver) HDL molecules are smaller compared to LDL molecules and have a lower lipid count and higher protein count. This is significant because the higher protein content lends itself to lessened probabilities of negative modifications, such as oxidation. (Lipoproteins and Apoproteins) The other major molecular difference between HDL and LDL is the apoproteins found on each are slightly different. HDL is high in the apoprotein, apoA-I which acts as a cholesterol gobbler, whereas LDL is high in ApoB-100 which is responsible for the delivery of cholesterol to tissue cells. (Lipoproteins and Apoproteins)
HDL does not transport cholesterol to tissue cells like LDL does, but instead recycles excess blood cholesterol through the liver where it can be excreted through bile or converted to bile salts. (Cholesterol, Lipoproteins and the Liver) This process is called, reverse cholesterol transport and is mediated through receptors. HDL helps to clean up some of the plaque LDL deposits in arteries. So in other words, HDL tries to keep cholesterol equilibrium when its evil twin, LDL gets out of whack! Good cholesterol can be increased through proper diet and eating healthier fats that contain omega-3, omega-6’s, and Vitamin E. These antioxidants are commonly found in monounsaturated and polyunsaturated fatty acid sources such as nuts, olives/olive oil, fatty fish, avocados/oil, and flaxseed/oil. Increasing dietary fiber can also be extremely effective in lowering cholesterol and protecting heart health. In particular, soluble fiber because it slows the absorption of nutrients, gives cholesterol ample time to bind to bile acids, these bile acids are then excreted through the intestines, and the liver uses excess cholesterol in the body to produce more bile acids, thus lowering total cholesterol. (Chandler)
The Good and The Bad
Maintaining healthy cholesterol levels in the body is a balancing act. When LDL levels are elevated (above 100 mg/dL ) and HDL levels are low (below 40 mg/dL) cholesterol can become a health concern over time. According to the CDC, 31.7% of Americans have high, LDL levels or above 160 mg/dL. (High Cholesterol Facts) Some research suggests pre-menopausal women are at lower risk than men to have elevated LDL levels. (Cholesterol Levels: What You Need to Know) PeproTech a cytokine producer says, “Interestingly, HDL and LDL particle sizes are significantly larger in women than in men, which may account, at least in part, for the longer life expectancies of women.” (Lipoproteins and Apoproteins) Common risk factors for high cholesterol depend mostly on diet and family history. But physical activity, age, body weight, cigarette smoking, high blood pressure and ethnicity also act as potential risk factors. (Cholesterol Levels: What You Need to Know)
But to say cholesterol should be completely avoided or that it is unimportant in the body would be false. Cholesterol, when controlled and maintained at normal levels is essential for vital functions in the body. First, it helps to stabilize cell membranes so the membrane is not completely permeable to external or potentially dangerous molecules. (Why Do We Need Cholesterol?) Without impermeable cell membranes anything could get into cells and essentially poison, infect, or kill a human being. Upholding proper cell membrane permeability also lends itself to moisturized and healthy skin. That’s right, without a permeable cell membrane the skin is unable to maintain proper moisture, causing dry and flaky skin. (Cholesterol on Skin) Cholesterol is also a substrate for the synthesize of Vitamin D from UV rays in the body, so without it the body could not naturally produce Vitamin D, a very important vitamin for bone health, energy, overall health, and immunity. (Why Do We Need Cholesterol?) Cholesterol is also the main building block for essential steroid hormones such as estrogen, progesterone, testosterone, cortisol, and aldosterone. (Why Do We Need Cholesterol?) These steroid hormones are extremely important for human reproduction, water/salt regulation, blood pressure, stress management, energy, immune health, and much more. Finally, the body would have a hard time digested fats without cholesterol. This is because bile acids which are made in the liver with cholesterol as a substrate, essentially emulsify fat in the stomach and allows that fat to become permeable to the cell membrane so enzymes can break it down to use for further functions. (Why Do We Need Cholesterol?) An interesting article I found from, Psychology Today written by Emily Deans, M.D., also stresses the importance of cholesterol for proper brain function. The nervous system is made up of one quarter of the body’s supply of cholesterol, and low levels of cholesterol has been associated with suicide as well as violence. (Low Cholesterol and Suicide)
“More specifically, cholesterol depletion is known to impair the function of the serotonin 1A receptor, the serotonin 7 receptor, and reduces the ability of the serotonin transporter to move serotonin in and out of the synapse. It is interesting that low serotonin in the spinal fluid is also associated with suicide, impulsive acts, hostility, and aggression – and low serotonin in the spinal fluid is associated with low cholesterol. Cholesterol is also needed for the formation of the synapse, to make myelin, the specialized insulating covering of the nerves, and in various other neurotransmitter signaling processes associated with anxiety, depression, and aggression.” (Low Cholesterol and Suicide)
There’s still a lot we don’t know about cholesterol and the way it affects various organs and systems in the body. But the information we do know is extremely interesting and beneficial for anyone going into the health-care field. According to the CDC, “Between 1999 and 2012, the percentage of American adults with high total cholesterol decreased from 18.3% to 12.9%.” (High Cholesterol Facts) So, on the bright side, the U.S. has made some progress in getting unhealthy levels of cholesterol under control. It’s funny, when I told my Mom I was writing a report on cholesterol her initial response was, “Oh, cholesterol is really bad, right?” Unfortunately, most people do not give cholesterol credit where credit is due, without it there would be no me and no you!
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