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Medically reviewed by: Mary L. Gavin, MD

What Are Fats?

Fats are nutrients in food that the body uses to build cell membranes, nerve tissue (including the brain), and hormones. The body also uses fat as fuel. If fats eaten aren't burned as energy or used as building blocks, they're stored by the body in fat cells. This is the body's way of thinking ahead: By saving fat for future use, it plans for times when food might be scarce.

Though too much fat can be unhealthy, certain kinds of fat are good for us and are an important part of a healthy diet.

What's Bad About Fat?

Fat gives food flavor and texture, but it's also high in calories, and eating too much fatty food can cause many health problems. For kids and teens, fast food, fried food, and snacks are a significant source of fat. Kids also get fat from high-fat dairy products (like whole milk, cheese, cream, and butter) and high-fat meats (like bacon, hot dogs, and fattier cuts of red meat).

Restaurant and takeout meals tend to have more fat than home cooking. Fried foods are the highest in fat content. Fat also often "hides" in foods in the form of creamy, cheesy, or buttery sauces or dressings.

Why Are Some Fats Healthy?

Healthy fats are an important part of a nutritious diet for both kids and adults. Getting enough healthy fats is essential for growth and development. Young kids need enough of them in their diet for normal brain development.

Besides supplying fuel for the body, fats:

  • help the body absorb fat-soluble vitamins (vitamins A, D, E, and K), which can only be absorbed if there's fat in a person's diet
  • are the building blocks of hormones
  • are important for brain health
  • help people feel full, so they're less likely to overeat

Fat is a great source of energy, but has twice the calories in the same amount of carbohydrates or protein. For example, 1 gram of fat provides 9 calories, whereas 1 gram of carbohydrates or protein provide 4 calories.

What Kinds of Fats Are in Food?

To help you figure out fats, here's a look at the three major types:

1. Unsaturated fats: Found in plant foods and fish, these are seen as neutral or even beneficial to heart health. Unsaturated fats are:

  • monounsaturated, found in avocados; peanut butter; nuts like almonds and pecans; and olive, peanut, and canola oils
  • polyunsaturated, found in most vegetable oils, like corn and soybean oil
  • omega-3 fatty acids, a type of polyunsaturated fat found in fatty fish like salmon, walnuts, and flax seeds

2. Saturated fats: Found in meat and other animal products, such as butter, shortening, lard, cheese, and whole milk and cream. Coconut oil is also high in saturated fat. Eating too much saturated fat can raise blood cholesterol levels and increase the risk of heart disease.

3. Trans fats: Found in some stick margarines, commercial snack foods, baked goods, and some commercially fried foods. Trans fats are created when vegetable oils are hydrogenated (hydrogen atoms are added to the fat molecule so they remain solid at room temperature). Trans fats can raise cholesterol and increase the risk of heart disease. Food manufacturers must list trans fats on food labels. Many companies have removed trans fats from their products.

How Are Fats Listed on Labels?

The Nutrition Facts label lists total fat, saturated fat, and trans fat found in 1 serving. But it's easy to eat a portion that's larger than the serving size on the label. A bag of corn chips might list 12 chips as a serving size, but many people eat 2 or 3 times that amount.

When it comes to fat, food packages often use terms such as fat-free, low-fat, reduced fat, and light (or lite). The government has strict rules about the use of these claims. By law:

  • fat-free foods contain no more than 0.5 grams of fat per serving
  • low-fat foods contain 3 grams of fat or less per serving
  • light (lite) foods must contain 50% less fat or one third fewer calories per serving than the regular version of that food
  • reduced-fat foods must contain 25% less fat per serving than the regular version

Light (lite) and reduced-fat foods may have more sugar and still be high in fat if the regular version was high in fat to begin with. 

How Much Fat Should Kids Get?

Fat and cholesterol play important roles in brain development. Healthy fats are a vital part of a child’s diet, and they should not be excessively limited or banned. Do not restrict fat in infants under 1 year old. For children over 2 years, try to limit saturated fat to less than 10% of the diet.

How Can I Keep Fats Under Control?

Eating the right kind and amount of fat is an important part of a healthy diet. But many kids eat too much fat, which might lead to unwanted weight gain. Kids who carry excess weight have greater risk of high cholesterol, high blood pressure, diabetes, and other medical problems.

Here are some ways to encourage healthy eating:

  • Serve foods that are naturally low in fat, such as fruits and vegetables, whole grains, lean meats and fish, and low-fat dairy products.
  • Choose healthier, unsaturated fats when preparing meals and reduce the amount you use.
  • Choose a variety of proteins, including lean meat and poultry (without skin), fish and seafood high in omega-3s, and vegetarian options, like beans and nuts.
  • When cooking meat, fish, or poultry, opt for broiling, grilling, or roasting (on a rack). These methods allow the fat to drip away during cooking, which cuts down on calories too. Frying, on the other hand, adds fat.
  • Pack school lunches, snacks, and meals for family outings. This keeps you in control of what your family eats. Limit dining out, especially at fast-food restaurants.
  • When you do dine out, help kids make healthy choices. For example, make a green salad part of the order and use low-fat dressing on the side. Try mustard instead of mayonnaise on sandwiches. Choose baked, grilled, or steamed dishes rather than fried.

The best way to teach kids healthy eating habits is to set a good example yourself. For a healthy lifestyle, make sensible eating a habit, choose a variety of foods including healthy fats, and exercise regularly.

Medically reviewed by: Mary L. Gavin, MD
Date reviewed: May 2022