Fats have twice as many calories per gram as carbohydrates or protein
Fats have 9 calories per gram, while carbohydrates and protein contain 4 calories per gram. As a calorie source, fats are more dense than almost anything that one would eat. High fat items include butter, cheese, lard, margarine, and many meats.
Fats provide a flavor and texture to foods that make a number of foods easier to take.
Not all fats are created equal, and we will attempt to go through the essential differences between the fats.
Trans fatty acids - fats are manufactured from vegetable oil...
...some forms of margarine being the most commonly consumed trans fat. While vegetable oils are healthy, when they are processed they change to an unhealthy product. Trans fats are unhealthy and are implicated strongly in heart disease, probably because they raise the bad cholesterol (LDL). Unfortunately, labels such as “cholesterol free” or “cooked in vegetable oil” do not indicate that these products contain high content of trans fats. Trans fats are another reason to avoid processed foods. The Food and Drug Administration now is requiring that the content of these dangerous fats be included on the label of foods. Some companies, such as Pepsi® and Frito Lay®, have eliminated trans fats from some of their food products.
Trans fats are used commercially to fry foods such as most baked goods, potato chips, French fries, and are found in foods such as vegetable shortening, some margarine, crackers, candies, baked goods, cookies, snack foods, fried foods, salad dressings, and many processed foods.
Reading food labels is the best way to learn about the content of trans fat. If the ingredient list includes the words “shortening,” “partially hydrogenated vegetable oil” or “hydrogenated vegetable oil,” the food contains trans fat. Because ingredients are listed in descending order of predominance, smaller amounts are present when the ingredient is close to the end of the list. Restaurants are not required to label their food, although a number of web sites will list the trans fats in the foods they prepare.
To avoid trans fats, substitute olive oil and garlic instead of butter or margarine. Nut butters and humus are good choices. Get rid of the vegetable spray that you use to coat your pans and instead buy a spray bottle and fill it with olive oil or canola oil—it will be less expensive, it will taste better, and it will be heart-healthy.
Saturated Fatty Acids - raise cholesterol and increase the risk of heart disease
These fats are usually sold in solid form and stored at room temperature. The primary sources of this fat are animal. They include lard, whole milk, and shortening.
Monounsaturated Fatty Acids - fats that are liquid at room temperature...
...but begin to solidify as they are refrigerated. Some salad dressings appear cloudy once they are refrigerated. These fats seem to lower blood cholesterol when used as substitutes for saturated fats. The sources of this fat are plants like nuts, avocados, olives, peanuts, and canola beans.
Polyunsaturated fatty acids - are considered essential fats...
...because they are required for your body to build cells and hormones. These fats are liquid at room temperature and include the healthy omega-3 fatty acids. They are also found in plant oils such as safflower, sunflower, corn, flaxseed and canola oils, as well as in seafood. Essential fatty acids—alpha-linolenic and linoleic acid—are also in the polyunsaturated group.
Good fats are still high in calories
The avoidance of trans fats and animal fats contributes to a healthy lifestyle. While trans fats will not be required in nutritional labels until 2006, until that time, avoiding processed foods that are not specifically labeled is a wise choice. Fats are still high in calories and should be minimized in any diet.
One of the difficulties with low carbohydrate diets is that they are typically higher in fat than we would recommend. When people go off the low carbohydrate diets they tend to maintain a high fat content in their diet, and regain the weight they lost, as well as add more. The addition of fat to high glycemic index carbohydrates makes a deadly combination for weight gain.