Fat, Food and Your Health
Fat. The mere sound of the word strikes fear in the hearts of millions. But heart disease isn't the only illness linked to a high-fat diet. Stroke, several types of cancers and even poor eyesight may be caused by consuming too much of it.
Since the late 1980s, fats have become the enemy. Early research indicated that fat increased cholesterol, which was a known risk factor for heart disease. These studies have led grocery stores to pack their shelves with no-fat and low-fat products. Many consumers have been avoiding all fats whenever possible.
However, some types of dietary fat are actually essential for good health. They increase your energy, keep your hair and skin soft and healthy, fight depression and may actually reduce your risk of heart disease and cancer.
Fats are required to make hormones in our bodies and to facilitate cell growth. Vitamins A, D, E and K need fat to be absorbed into the blood stream. And, according to Micheline Hansen, dietitian for Albertson's grocery chain, "It's the fat in your diet that helps you feel full and balances your blood sugar."
First Things First
Before discussing the types of fat, it is important to briefly discuss cholesterol. Cholesterol is the main villain in heart health, and dietary fat is directly related to cholesterol levels in the blood. High levels are associated with increased risk of arteriosclerosis and other heart diseases. However, as with fat, there are good and bad cholesterols.
LDL, formally known as low-density lipoprotein, is the bad cholesterol. "Think of the L as Lousy and Lethal," suggests Dr. K.C. Hayes, nutritional researcher in lipids for 35 years.
HDL, or high-density lipoprotein, is the good cholesterol. Dr. Hayes teaches his students at Brandeis University that the H is for Helpful and Healthful.
How do these two types of cholesterol work together? "Think of Mardi Gras or some other big party," says Dr. Hayes. The LDL is the litter; the HDL are the cleaners. The bigger the party, that is, the more fat you eat, and the more litter you have in the streets, or arteries. The cleaners come through and sweep the streets, clearing them to allow normal transport. "Oftentimes, the HDL is overworked and underpaid, which leads to more and more clutter in the streets," says Dr. Hayes. Eventually, it gets so clogged that no traffic can get through at all – which is bad news for cars, and blood.
Different fats affect the production of cholesterol in different ways. Here is a breakdown of the good, the bad and the ugly.
Unsaturated fats are healthy fats. They contain the essential fatty acids that our bodies are unable to produce on their own. They also help lower LDL cholesterol. As an added bonus, many of these fats are rich in antioxidants, which have been shown to protect against cancer and heart disease. They are derived mainly from plant sources and are liquid at room temperature. Unsaturated fats are broken down into two categories: monounsaturated and polyunsaturated.
Experts believe that one reason heart disease is so rare in Mediterranean countries is because of their diet rich in monounsaturated fats. Olive oil, canola oil and a wide variety of nuts contain this heart-friendly fat, which is believed to lower LDL cholesterol and total cholesterol when used in place of saturated fat.
Polyunsaturated fats are found in vegetable oils, including corn, safflower, soybean and sesame seed. Additionally, they can be found in some nuts, such as walnuts and pine nuts. These fats are responsible for providing our bodies with the essential fatty acids Omega-3 and Omega-6.
According to Dr. Udo Erasmus, author of Fats that Heal, Fats That Kill, Omega-3 fatty acids "reduce appetite, elevate mood, decrease inflammation, give more energy and make you feel more active."
Unfortunately, most of us don't get enough of them. "The easiest way to get your Omega-3s is through fresh nuts, green leafy vegetables, seeds and deep sea, cold-water fish such as salmon, mackerel and tuna," says Dr. Richard Mabray, a gynecologist and nutrition expert.
Luckily, getting our Omega-6s is easier. The bulk of our polyunsaturated fats come from Omega-6 fatty acids, which are abundant in most cooking oils, and therefore, in most of the foods we eat.
It's true. Despite all of the conflicting information on fat, French fries and hot fudge sundaes are still a no-no. Full of artery-clogging saturated fat, these favorites should be saved for rare occasions.
Saturated fat continues to wear the black hat when it comes to heart health. Found primarily in animal products, including meat, milk and eggs, saturated fat is usually a solid at room temperature. It increases LDLs and is strongly associated with numerous maladies, including heart disease and stroke.
And The Ugly
Trans fats are the new fats on the scene, and they may be even worse than saturated fats. They are formed by taking a healthy unsaturated fat, like canola oil, and hydrogenating it to prolong shelf life. Trans fats have been shown to increase LDLs while decreasing HDLs. To use Dr. Hayes' example, the party is getting bigger, the litter is piling up, but the cleaners are being laid off.
"Gram for gram, trans fats have 15 times more risk for inducing coronary heart disease than saturated fats," says Dr. Hayes. Although you get less trans fat in your diet, even small amounts greatly increase your risk.
The other problem with trans fat is that it is not currently represented on food labels. To get an idea of the amount of trans fat in a product, read the ingredients list – the closer to the top you see any form of hydrogenated oil listed, the higher the amount of trans fat it contains.