Does Eating Low-fat Foods Help You Lose Weight?

Michael Pollan, author of "Food Rules," says that since low-fat diets began gaining popularity, the average American woman is 19 lbs. heavier and the average man 17 lbs. heavier than in the late 1970s. Yet, the USDA Dietary Guidelines say consumption of fat is part of a healthy diet. Apparently, the answer to the question of whether or not eating low-fat foods helps with weight loss is not as simple as it seems.

Losing Weight

As all dieters know, to lose weight, you must take in fewer calories than you burn. The USDA Dietary Guidelines' calorie recommendations help people determine how many calories they need each day for good health. Women over 19 need between 1,600 and 2,400 calories, and men need between 2,000 and 3,000. Age and level of activity determine where on the range you fall. To lose weight, eat around 500 calories less than the recommendations daily.

Calories in Fat

According to Marion Nestle, author of "What to Eat," fat has 45 calories per teaspoon, while both protein and carbohydrates have 20 calories per teaspoon. Eating low-fat foods will help you cut calories and achieve the 500 fewer calories a day you need to lose weight. Fruit, vegetables and whole grains are naturally low-fat foods that also contain high levels of nutrients.

USDA Dietary Guidelines

The USDA Dietary Guidelines recommend some low-fat foods, such as fat-free or low-fat dairy products, lean meats and a diet that, overall, is low in saturated fats and trans fats. Lean meats are those cuts without lots of fatty streaks, or marbling, such as round steak or flank steak. Other examples include pork fillets instead of pork ribs and skinless chicken breasts instead of chicken thighs.

Types of Fat

Fats come in three varieties: saturated fats, such as shortening and animal fats, which are solid at room temperature; unsaturated fats, such as olive oil and butter, which are liquid at room temperature, but harden in cooler temperatures; and polyunsaturated fats, such as safflower oil, which stay liquid at all temperatures. Saturated fats and partially hydrogenated, or trans fats, which have been treated to last longer in your cupboard, are both cited in the Dietary Guidelines as fats to avoid because they cause heart disease. They are lower in calories than some unsaturated fats, but their health risks outweigh their low-calorie benefits.

Making Wise Choices

Low-fat foods may contain less fat than other foods, but they may equal or even exceed the number of calories in similar products. As Michael Pollan points out, many low and non-fat foods contain extra sugar and carbohydrates to make up for the loss of flavor from fat.

If you substitute a low-fat product, such as milk or sour cream, for the higher fat version, you will consume fewer calories overall and will lose weight. But if you eat low-fat cookies on a regular basis, thinking that they will help you lose weight, you will add more calories than you can burn over time, and you will actually gain weight.