Dietary factors have been known to contribute to cardiovascular health for decades. This area continues to be a major area of research into human health. Components of diet can also affect cholesterol levels, so it is natural to discuss both topics together.
Elevated cholesterol levels have long been established to increase the risk of cardiovascular disease. As prior columns have reported, cardiovascular disease is the number-one cause of line-of-duty deaths among firefighters. This is important since screening for elevated cholesterol levels and controlling cholesterol levels is a primary therapy at preventing cardiovascular disease. Preventing cardiovascular disease reduces the chance of having a heart attack.
While guidelines in the past focused on total cholesterol levels, current guidelines focus on the subtypes of cholesterol that may not be familiar to some. The first component of cholesterol is low-density lipoproteins (LDL). This also is referred to as the "bad cholesterol." LDL cholesterol is responsible for transporting cholesterol that is synthesized in the liver to the peripheral tissues. It is thought that LDL cholesterol deposits cholesterol molecules in the walls of damaged blood vessels, contributing to atherosclerosis, or plaque formation, within the blood vessels. It is these plaques that rupture in the arteries of the heart and cause heart attacks. Elevated LDL levels are a risk factor for cardiovascular disease.
The other component of cholesterol is high-density lipoproteins (HDL). This molecule has the opposite mechanism of LDL cholesterol and is considered the "good cholesterol." HDL cholesterol transports cholesterol molecules from the peripheral tissues back to the liver for processing. Higher levels of HDL cholesterol are considered a negative risk factor for cardiovascular disease and reduce the risk of cardiovascular disease. Table 1 lists the classification of the two different types of cholesterol.
In the past, preventative measures for cardiovascular disease looked at total cholesterol levels for overall cardiovascular disease risk. However, because of the different natures of the two subtypes of cholesterol, risk-reduction measures factor the levels of both types of cholesterol with the main focus on LDL levels instead of total cholesterol levels. High LDL levels increase the risk of cardiovascular disease while high levels of HDL cholesterol reduce the risk. Understanding this concept will help you communicate with your health care provider when discussing cholesterol levels and help you take control of your health.
Determining a goal LDL level also depends on your overall risk of cardiovascular disease (Table 2). In general, an LDL level less than 100 is optimal with a level greater than 130 being considered high. For patients with established cardiovascular disease or diabetes, the goal LDL is less than 100 (Table 3). From a preventative medicine standpoint, diabetics are at such an increased risk of developing cardiovascular disease that these patients are considered having cardiovascular disease even in the absence of an established diagnosis. For patients with two or more risk factors for cardiovascular disease, the goal LDL is less than 130. If you only have one or less cardiovascular risk factor in Table 2, your goal LDL is 160, but still lower levels are optimal. Also, an HDL level greater than 60 is a negative cardiovascular disease risk factor; the total number of cardiac risk factors from Table 2 is reduced by one. For example, using Table 2, if you are over 45 and are being treated for high blood pressure, using Table 3 you have two cardiovascular risk factors and your goal LDL is less than 130. Now if you have an HDL level greater than 60, your total number of risk factors is reduced by one and your goal LDL is less than 160.
The first step to reducing LDL levels is lifestyle changes. These include consuming a low-fat diet, exercising and quitting smoking. Despite the attempts at controlling cholesterol levels with lifestyle changes, new research suggests that there is a genetic component to cholesterol. Current thinking is that cholesterol metabolism is hereditary, so if you have elevated LDL levels, there is a good chance you will need medical therapy. If after a month or so after dietary measures have been implemented LDL levels are not at acceptable levels, your health care provider should start medical therapy.
Diets can contribute to cholesterol levels in the body. Diet modification is a primary therapy at lowering cholesterol levels. Research in this area has changed current thinking regarding cholesterol and diets. Diets high in cholesterol were once thought to increase cholesterol levels in the body. However, recent studies suggest that it is not the cholesterol content in diets that contribute to cholesterol levels in the body, but the content of saturated fats. Current recommendations reflect this in recommending a diet low in saturated fat rather than low in total cholesterol. In 2006, the American Heart Association (AHA) released dietary guidelines for a heart-healthy diet. The AHA recommends a diet high in fruits and vegetables, whole grains, lean meats, poultry and fish and low in saturated fat. Table 4 offers examples of foods consistent with the AHA recommendations.
It is very easy to become confused on what are good dietary habits and what are not just due to the huge volume of information available. Many good resources are available at no or minimal cost. Good resources to start are any cookbooks developed by The Mayo Clinic, The American Heart Association and Weight Watchers. Online resources are available at the National Volunteer Firefighter Council (NVFC) website accessible at http://www.healthy-firefighter.org/; the Mayo Clinic has free recipes accessible at http://www.mayoclinic.com/health/heart-healthy-recipes/RE00098.
These resources offer recipes that do not sacrifice flavor while maintaining a healthy diet. It also nearly impossible to adhere to a strict diet. For example, if you have the urge to eat a donut, go ahead; just don't make a habit of eating a donut every day. Try to adhere to a healthier diet 90% to 95% of the time and you will improve your overall health and reduce your risk of cardiovascular disease.
Table 2: CARDIAC RISK FACTORS FOR TREATMENT OF CHOLESTEROL
* Cigarette smoking
* High blood pressure or currently being treated for high blood pressure
* Low HDL cholesterol (&llt;40 mg/dL)
* Family history of CVD (cardiovascular disease)
* (CVD in male first-degree relative &llt; 55; CVD in female first-degree relative &llt; 65)
* Age (men ⩾45; women ⩾55)
* Cardiovascular disease
* Diabetes mellitus*
*Considered to be equivalent to CVD
Note: HDL levels greater than 60 are considered a negative risk factor for cardiovascular disease and reduce the total number of cardiovascular risk factors by one.
From "Executive Summary of the Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III)" by The Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults, 2001, Journal of the American Medical Association, 285, p. 2487. Copyright © 2001, American Medical Association. All rights reserved. Adapted with permission.
From "Executive Summary of the Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III)" by The Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults, 2001, Journal of the American Medical Association, 285, p. 2487.
Copyright © 2001, American Medical Association. All rights reserved. Adapted with permission.
DR. RAYMOND BASRI, MD, FACP, is in the private practices of internal medicine and diagnostic cardiology in Middletown, NY. Dr. Basri is a Diplomate of the American Board of Internal Medicine and president of the Mid-Hudson Section. He received the 2008 Laureate Award of the American College of Physicians, of which he is a Fellow. Dr. Basri also is clinical assistant professor of medicine at New York Medical College, attending physician in the Department of Internal Medicine at Orange Regional Medical Center and on the consulting staff in cardiology at The Valley Hospital in Ridgewood, NJ. He is a member of the Excelsior Hook and Ladder Company in Middletown and a deputy fire coordinator for Orange County. Dr. Basri is the senior physician of the Disaster Medical Assistance Team (DMAT NY-4). He is a senior aviation medical examiner for the Federal Aviation Administration (FAA) and chief physician for Health & Safety Specialists in Medicine, which does onsite medical examinations for the fire service and consultant to FirePhysicals.com. ERIC BERGMAN, PA-C, is a physician assistant practicing internal medicine at Hartford Hospital in Hartford, CT. He earned a bachelor of science degree in allied health from the University of Connecticut and a master's degree from Albany Medical College. He is a member of the Killingworth, CT, Volunteer Fire Company; a past company officer and life member of the Avon, CT, Volunteer Fire Department; and a past member of the Shaker Road-Loudonville Fire Department in Colonie, NY.
