Dietary Fats: Separating The Bad From The Good
For years, eating a low fat diet has been touted as being essential to losing weight and controlling or preventing cardiovascular disease. However, recent research shows that it's not simply how much fat you eat, but rather what type of fat. It appears that not all fats are created equal when it comes to maintaining a healthy diet. Read on to learn more about the different types of dietary fats.
There are four major types of fat and each of them differs based on their chemical structure and effects on your health. Eating too much of the "bad" fats (saturated and trans fats) may increase the risk for certain diseases, while eating the "good" fats (monounsaturated and polyunsaturated fats) may actually lower disease risk. The key to a healthy diet is to eat more of the good fats, minimize saturated fats and to avoid trans fats.
The "Bad" Fats
There are two main types of dietary fats that have been shown to have a detrimental effect on your health. These include:
- Saturated Fats: This type of fat is mainly derived from meat and dairy products. Eating foods rich in saturated fats have been shown to increase LDL cholesterol as well increase your risk for cardiovascular disease and Type 2 diabetes. Foods with saturated fat include animal products such as red meat, poultry, pork, seafood, eggs, milk, lard and butter. Coconut and palm oils also contain saturated fat. The American Heart Association (AHA) suggests that no more than 7-percent of your total calories should come from saturated fats.
- Trans Fats: The majority of trans fats in your diet are created artificially by a chemical process called partial hydrogenation that occurs during the manufacturing of many foods. Trans fats help to extend the shelf life of food, provide a less greasy feel, and create a pleasing creamy texture. Many commercial baked goods (crackers, cookies and cakes) and fried foods (doughnuts and fries) are rich in trans fats. Furthermore, foods that list "partially hydrogenated oils" on their ingredient list also contain trans fats. Trans fats are thought to be the worst type of fat as it simultaneously increases LDL cholesterol and decreases HDL cholesterol. The AHA recommends limiting the amount of trans fats you eat to less than 1-percent of your total daily calories.
The "Good" Fats
Unsaturated dietary fats, when eaten in moderation, have been shown to have a beneficial effect on overall health. There are two main types of unsaturated fats. These include:
- Monounsaturated Fats: Eating foods rich in monounsaturated fats have been shown to reduce LDL cholesterol, lowering your risk of heart disease and stroke. Additionally, consumption of monounsaturated fats has also been associated with improved insulin and blood sugar levels. Foods high in monounsaturated fats include vegetable oils such as olive oil, canola, oil and sesame oil. Other sources of these fats include avocados, peanut butter, and a variety of nuts.
- Polyunsaturated Fats: Evidence shows that eating foods rich in polyunsaturated fats improves blood cholesterol levels, which can decrease your risk of heart disease. Polyunsaturated fats may also help decrease the risk of type 2 diabetes. Polyunsaturated fats also encompass essential fats, which are fats that your body requires to function properly but can't produce. Therefore, these essential fats, specifically omega-6 and omega-3 fats must be procured through your diet. Omega-6 and omega-3 fats are essential to maintaining cognitive function and for the overall growth and development of the body. Furthermore, the consumption of omega 3 fats has been shown to decrease your risk of coronary heart disease, depression, and arrhythmias. Foods high in polyunsaturated fat includea number of vegetable oils, including soybean oil, corn oil and safflower oil, as well as fatty fish such as salmon, mackerel, herring and trout. Other sources include some nuts and seeds such as walnuts and sunflower seeds.
Although there is no recommended guideline for how much unsaturated fats you should eat, the AHA suggests that a majority of your fat intake (which should not exceed 25-to-35 percent) should be derived from unsaturated fats.
Calculating Your Recommended Daily Fat Intake
The AHA recommends that no more than 7-percent of your daily calories should come from saturated fat. In order to calculate how many calories per day this translates to, multiply your daily caloric intake by 7-percent and divide that by nine (the number of calories in a gram of fat). For a 2000 calories per day diet, 140 calories (which is equivalent to about 16 grams of saturated fat) should come from saturated fat.
The Bottom Line
The American Heart Association suggests that your daily fat intake should not exceed 35-percent of your total calories. Furthermore, most of these calories should be derived from the "good" fats specifically monounsaturated and polyunsaturated fats. Conversely, saturated and trans fats should not exceed more than 7-percent and 1-percent, respectively, of your daily caloric intake.