Summertime! Time for picnics and pigging out — fresh salads AND ice cream!
Our own Kristen Rezabek (MS, RD, CD; MG Class of 2013) gives us the heads up on the fats in our food.
Fat has long gotten a bad rap for its contribution to weight gain, heart disease and certain types of cancer. But not all fats are created equal. And fat does have important roles in the body; it helps protect our vital organs from injury, it insulates to keep us warm, it carries and stores essential vitamins and helps make up certain cells and hormones in the body. So knowing which fats are healthier than others is a first step in controlling your weight and reducing your risk for chronic disease.
Saturated fat, trans fatty acids and dietary cholesterol raise blood cholesterol. Monounsaturated fats and polyunsaturated fats don’t. Some studies suggest the mono and polyunsaturated fats might even help lower LDL cholesterol slightly when eaten as part of a low saturated fat diet.
So how can you tell your fats apart?
Saturated fat is the main dietary cause of high blood cholesterol, and in particular LDL (bad) cholesterol. The American Heart Association recommends you limit your saturated fat intake to less than 20 grams a day. Most saturated fat in our diet comes from animal products as well as tropical oils. Animal sources include beef, veal, lamb, pork, lard, poultry fat, butter, cream, milk, cheeses and other dairy products made from whole milk. The tropical oils that contain saturated fat include coconut oil, palm oil, palm kernel oil, and cocoa butter.
Polyunsaturated and Monounsaturated Fats
Polyunsaturated and monounsaturated fats are unsaturated fats. They’re often found in oils from plants. Polyunsaturated fats include safflower, sesame and sunflower seeds, corn and soybeans, and many other nuts and seeds and their oils. Monounsaturated fats include canola, olive and peanut oils, and avocados. Both polyunsaturated and monounsaturated fats may help lower your blood cholesterol when you use them in place of saturated fats in your diet. But a moderate intake of all types of fat is best (less than 60 grams of total fat per day). Use polyunsaturated or monounsaturated oils — and margarines and spreads made from them — in limited amounts. This is better than using fats with a high saturated fat content, such as butter, lard or hydrogenated shortenings.
Omega 3 fatty acids are a type of polyunsaturated fat found in shellfish and fish, soybeans, canola oil, wheat germ, flax seed and walnuts. A number of studies have suggested that people who eat a diet rich in fish are less likely to develop Alzheimer’s and heart disease. Omega 3 fatty acids may help lower your risk for these diseases by helping prevent blood clots from forming, lowering cholesterol levels and decreasing high blood pressure. Good sources of omega-3s include cold-water fish such as salmon, halibut, mackerel, sardines and herring, and fish-oil supplements. However before taking any type of supplement check with your doctor first, particularly if you are on blood thinning medication. Doses greater than 3 grams a day of fish oil are not recommended due to the side effects.
Trans Fatty Acids
During food processing, liquid fats like vegetable oil may undergo a chemical process called hydrogenation, which changes the structure of the fat to make it more solid. This fat is called a trans fat. This process is common in making margarine and shortening. These trans fats raise LDL cholesterol just like a saturated fat, however they will also lower your HDL (good) cholesterol. You find many commercial baked goods such as crackers, cakes, and cookies made with hydrogenated fat. There is no recommendation for the amount of trans fat in the diet, just to limit this type of fat as much as possible. Soft or liquid margarines are lower in trans fat. Trans fats are found in small amounts in various animal products such as beef, pork, lamb and the butterfat in butter and milk.
The American Heart Association recommends that consumers follow these tips:
(liquid or tub varieties) over harder stick forms. Shop for margarine
with no more than 2 grams of saturated fat per tablespoon and with
liquid vegetable oil as the first ingredient. Look for those labeled
“trans fat free.”
french fries, cakes and cookies. Not only are these foods very high in
fat, that fat is also likely to be hydrogenated, meaning a trans fat.