Cholesterol. Get Your Fats Straight!
Confused About The Difference Between Lipids, Fats And Cholesterol?
You're not alone! And it seems a lot of health professionals are confused as well, the way these terms are often bandied about in the same sentence.
Lipids is the umbrella term used to describe compounds that do not dissolve in water and includes fats, oils, lipoproteins, waxes, sterols (including cholesterol), and triglycerides. Lipids is the correct term to describe both fats and cholesterol.
Fats are large molecules with a specific type of structure that allows more energy storage than carbohydrates.
Cholesterols are a unique type of fat with quite a complicated structure.
Confusion Multiplied: Cholesterol Tests Actually Measure Lipoproteins
When your doctor tells you your "cholesterol" levels are high, what he/she really means is that your lipoprotein levels are not within the "normal range". "Cholesterol" tests measure:
- Total "cholesterol"
- Low Density Lipoproteins (LDL)
- High Density Lipoproteins (HDL)
"Cholesterol" is in quotation marks because all of these molecules are made of triglycerides + cholesterol + phospholipids + protein, in varying quantities. They are NOT just cholesterol.
Guidelines Differ In Recommendations For Cholesterol Monitoring
In actual fact, "cholesterol" blood tests only actually measure total cholesterol and HDL. The LDL and triglyceride component are just calculated using a mathematical equation.
Internationally, some professional bodies have recognized this shortcoming and have changed their guidelines to accommodate this less-than-ideal situation.
The United Kingdom's National Institute for Clinical Excellence (NICE) now recommends the calculation of non-HDL rather than LDL: Non-HDL = Total cholesterol minus HDL cholesterol, both measurable in blood. An association has been found between non-HDL cholesterol and recurrent episodes of angina and non-fatal myocardial infarctions (heart attacks) in people with preexisting coronary heart disease.
In the U.S., professional bodies have been slow to adopt using non-HDL cholesterol levels in clinical decision making, despite the National Cholesterol Education Program (NCEP) recommending that they use it as a secondary lipid-lowering target in people with elevated triglyceride levels. Contributing to the problem is the issue that not all laboratories provide non-HDL values in their printout sheet. Hopefully, in the future, the use of non-HDL values will become more mainstream, because it makes more sense to assess all of the circulating atherogenic lipoproteins as one measure.
Some Guideline Differences, Some Similarities
Although the 2016 American College of Cardiology Expert Consensus Decision Pathway still uses LDL values, they state non-HDL cholesterol values as well. In addition, they offer guidance with respect to what the anticipated response to therapy should be; for example, a 50% reduction in LDL-C or a non-HDL-C of less than 100 mg/dL.
The Good: Cholesterol Is Vital For Our Survival
To say that cholesterol gets a bad rap is an understatement. Its reputation for being associated with an increased risk of heart attack and stroke means it gets blanketed with the term BAD. But we wouldn't be ALIVE without cholesterol.
Cholesterol helps our body make bile acids; vitamin D; hormones such as estrogen, progesterone, testosterone, cortisol and aldosterone; and helps form cell walls. Although some cholesterol is obtained from our diet, most is made in the liver and other tissues. So if your "cholesterol" levels are high, there may be a genetic reason for it.
The Bad: High Cholesterol Is Associated With An Increased Risk Of Heart Attack Or Stroke
Experts believe that when there is too much cholesterol in your blood, it builds up on the walls of the arteries. Over time, this causes the arteries to "harden" and also attracts other cells and debris from the blood, narrowing the space that blood has to flow through. Since blood carries oxygen, tissues supplied by the narrowed blood vessel may become starved of oxygen, and cause symptoms such as angina pain or worse, a heart attack if complete blockage occurs.
Coming from a slightly different angle, other experts suggest it is inflammation, not cholesterol that starts this process. Cholesterol just happens to "latch" onto the inflamed blood vessel wall and contributes to the narrowing of the arteries.
The Ugly: Still More Questions Than Answers?
Even though it seems clear that having high blood cholesterol puts you at risk of heart disease, the whole cholesterol issue itself is more complicated than you think. Here's a few facts about cholesterol that may just leave you with more questions than answers!
- The 2015–2020 Dietary Guidelines for Americans, state that dietary cholesterol is "no longer a nutrient of concern for overconsumption" as there is no link between dietary cholesterol intake and heart disease. The guidelines still recommend a reduction in the intake of saturated fats, while other experts believe diets high in concentrated sugars, particularly sucrose and high-fructose corn syrup elevate cardiovascular disease risk more than diets containing saturated fats. At least everybody agrees that trans fats (those found in highly processed foods such as ready-made cakes, cookies and pie crusts), are definitely bad for you!
- At least eight major dyslipidemia guidelines are available; variations exist in their recommendations including need to reach target LDL levels (or not). Congruent recommendations would be less confusing to doctors and the public alike!
- Genetic high cholesterol conditions appear more common than previously thought, affecting 1:250 people overall, twice the amount previously thought; although risk varies with race and age.
Screening For Cholesterol: When Should It Happen?
All experts agree that cholesterol levels should be measured in ALL people with a history of coronary heart disease (CHD) or vascular disease (VD). However, the issue of when to screen people WITHOUT symptomatic CHD or VD is somewhat contentious.
The ACC/AHA Cardiovascular Risk Guidelines recommend all people aged 20 or older, with no previous diagnosis of cardiovascular disease (CVD), have their cholesterol levels checked every four to six years as part of a cardiovascular (CV) risk assessment.
The USPSTF takes a slightly different approach and makes recommendations about which populations would actually benefit from statin use for the primary prevention of cardiovascular disease. They concluded that adults aged 40 to 75 years with no history of CVD and at least one CVD risk factor with a 10-year cardiovascular event risk of at least 10% would benefit from a low-to-moderate dose statin. Evidence was insufficient to make any recommendations for adults aged over 76 years. For all other patients, the recommendation should be based on the patient's situation.
Targeting Cholesterol: Treatment
Millions of people in America are prescribed treatment for high cholesterol, and statins are the most commonly prescribed medication. Statins work by inhibiting an enzyme called HMG-CoA reductase, which controls cholesterol production in the liver. As a result, blood levels of LDL in the blood are lowered. Examples of statins include:
- atorvastatin (Lipitor)
- fluvastatin (Lescol)
- lovastatin (Altoprev, Mevacor)
- pravastatin (Pravachol)
- rosuvastatin (Crestor)
- simvastatin (Zocor).
Simvastatin and lovastatin are also available as the following combination cholesterol-lowering medications:
Statins: When To Initiate?
American Heart Association (AHA) and American College of Cardiology (ACC) guidelines recommend statin therapy depending on risk for cardiovascular heart disease.
The AHA/ACC recommend statin therapy should be considered for:
- Adults aged 40-75 without cardiovascular disease with a 7.5 percent or higher risk for having a heart attack or stroke within 10 years
- People with a history of heart attack, stroke, angina, peripheral artery disease, transient ischemic attack, or other cardiovascular event
- People aged 21 and older with very high LDL levels (190 mg/dL or higher)
- People aged 40-75 years with diabetes (either Type 1 or Type 2).
Note that these recommendations differ from the 2016 USPSTF guidelines discussed previously.
Other Medications To Lower Cholesterol
Several other classes of medicine also lower cholesterol, such as:
- Selective cholesterol absorption inhibitors - prevent the absorption of cholesterol from the intestine: ezetimibe (Zetia)
- Resins (also called Bile Acid Binding Drugs) increase the disposal of cholesterol in the intestine: cholestyramine (Questran, Prevalite), colestipol (Colestid), colesevelam (WelChol)
- Other lipid lowering therapies, including fibrates (best for lowering triglycerides and sometimes for increasing HDL), such as gemfibrozil (Lopid), fenofibrate (Antara, Lofibra); niacin; Lovaza and icosapent (Vascepa).
There is a lot you can do to decrease your risk of cardiovascular disease, regardless of whether or not you are already prescribed cholesterol lowering medication.
- STOP smoking (if you smoke) and try to avoid second-hand smoke.
- Eat plenty of vegetables, fruits, and whole foods; avoid processed foods that contain high amounts of salt and trans fats.
- Get ACTIVE. Exercise every day and sit down less.
- Keep your weight within a healthy range. Lose weight if you are overweight or obese.
- If you have diabetes, take your medication as prescribed and always try to keep your blood sugar levels within the normal range.
- Seek advice about how to limit stress and keep anger in check if you find you are always uptight.
- Get regular cardiovascular assessments if you have a family history of heart disease or stroke, particularly if your relatives had these conditions at a young age.
Finished: Cholesterol. Get Your Fats Straight!
- 2013 ACC/AHA Guideline on the Treatment of Blood Cholesterol to Reduce Atherosclerotic Cardiovascular Risk in Adults: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines
- Stone NJ, Robinson J, Lichtenstein A, et al. Circulation. 2013. doi:10.1161/01.cir.0000437738.63853.7a. https://circ.ahajournals.org/content/early/2013/11/11/01.cir.0000437738.63853.7a
- Writing Committee, Donald M. Lloyd-Jones, Pamela B. Morris, Christie M. Ballantyne, Kim K. Birtcher, David D. Daly, Sondra M. DePalma, Margo B. Minissian, Carl E. Orringer, Sidney C. Smith. 2016 ACC Expert Consensus Decision Pathway on the Role of Non-Statin Therapies for LDL-Cholesterol Lowering in the Management of Atherosclerotic Cardiovascular Disease Risk. Journal of the American College of Cardiology Jul 2016, 68 (1) 92-125; DOI: 10.1016/j.jacc.2016.03.519
- National Heart, Lung, and Blood Institute. High Blood Cholesterol: What You Need To Know. NIH Publication No. 05-3290. Revised June 2005. - http://www.nhlbi.nih.gov/health/resources/heart/heart-cholesterol-hbc-what-html
- Ramsay LE, Yeo WW, Jackson PR. Dietary reduction of serum cholesterol concentration: time to think again. BMJ. 1991 Oct 19;303(6808):953-7. - http://www.ncbi.nlm.nih.gov/pubmed/?term=1954418
- Hendrani AD, Adesiyun T, Quispe R, et al. Dyslipidemia management in primary prevention of cardiovascular disease: Current guidelines and strategies. World J Cardiol. 2016 Feb 26;8(2):201-10. doi: 10.4330/wjc.v8.i2.201. - http://www.ncbi.nlm.nih.gov/pubmed/26981215
- Cholesterol Medications. American Heart Association - http://www.heart.org/HEARTORG/Conditions/Cholesterol/PreventionTreatmentofHighCholesterol/Cholesterol-Medications_UCM_305632_Article.jsp#.WMCO84F97IU
- New USPSTF Guidelines Recommend Statins in ‘Appropriately Selected’ Primary-Prevention Patients. tctmd/The Heartbeat - https://www.tctmd.com/news/new-uspstf-guidelines-recommend-statins-appropriately-selected-primary-prevention-patients
- Jin J. Lipid Disorders: Screening and Treatment. Nov 15, 2016. JAMA. 2016;316(19):2056. doi:10.1001/jama.2016.16650 - http://jamanetwork.com/journals/jama/fullarticle/2584052