healthy fats after wls

What’s the Skinny on Healthy Fats After WLS?

October 27, 2017

Throughout our lives, most of us have heard that fat is bad. Everyone around us, from celebrities to our family and friends, has tried dieting and losing weight by cutting out fattening foods and listening to the latest fat-free diet trend. The reality is, fat is an essential part of a healthy, balanced diet. Fat is one of the three major nutrients, along with protein and carbohydrates, which our bodies need to survive. To eat a well-balanced diet, you should eat healthy fats after WLS.

Fat is Important

In the body, fat is used as an energy source and helps to support cell growth. Fat is also used to absorb vitamins and minerals. It is a cushion for the body’s organs and helps keep the body warm. Fat is a key component of the myelin sheath that protects nerve cells in the brain and is an essential part of the cell membrane that protects every cell in our body. It is also needed in the body for appropriate blood clotting, hormone production, and muscle movement. (1,2)

3 Main Types of Fats

Unfortunately, not all fat is created equally.
There are three main types of fat: unsaturated fat, saturated fat, and trans fat.

Unsaturated Fats

Unsaturated fats are liquids at room temperature. They are generally referred to as “good” or beneficial fat. Unsaturated fats have been shown to reduce a person’s risk of developing heart disease, improve blood cholesterol levels, decrease inflammation, and stabilize heart rhythms. (3)

Unsaturated fats can be found in many foods including:

  • Nuts
  • Fatty fish (salmon, tuna, lake trout, sardines, mackerel)
  • Flaxseed
  • Chia seeds
  • Eggs
  • Avocado
  • Peanut Butter
  • Vegetable Oils (olive oil, sunflower oil, canola oil, sesame oil, peanut oil)

Unsaturated fats can be further broken down into two categories: monounsaturated fats and polyunsaturated fats.

Monounsaturated fats are found in olive oil, avocados, nuts, peanut butter, and seeds. Polyunsaturated fats are found in walnuts, flax seeds, sunflower oil, soybeans, and fatty fish. Many of the polyunsaturated fats, including omega-3 and omega-6 fatty acids, provide essential fats that the body needs to survive, but can’t produce on its own. (3) Eating both of these types of unsaturated fat are crucial for optimal body functioning.

Saturated Fats

Saturated fats are typically solid at room temperature and are usually found in animal products, such as meat and dairy. (4)

Sources of saturated fat include:

  • Beef, lamb, and pork
  • Poultry skin
  • Cheese
  • Butter and lard
  • Cream
  • Coconut and coconut oil
  • Palm and palm kernel oil
  • Ice cream

Saturated fats used to be classified as a “bad” or harmful source of fat that can increase the risk of heart disease. Recent studies have shown inconclusive evidence to whether saturated fat is associated with an increased risk of developing heart disease. (3)

What is conclusive, however, is that eating unsaturated fats in place of saturated fats can prevent insulin resistance, decrease “bad” LDL cholesterol levels, and can improve the ratio of “good” HDL cholesterol to total cholesterol. (3)

Trans Fats

Trans fats, also known as trans fatty acids, are created when liquid vegetable oils are heated in the presence of hydrogen gas. This converts the liquid vegetable oil into a solid and changes its effect on the body. (3)

Trans fats are typically found in:

  • Fried foods
  • Fast food
  • Processed foods (especially microwave popcorn, frozen pizza, coffee creamers)
  • Baked goods
  • Margarine
  • Shortening

Trans fats are considered the “worst” or most harmful type of fat. They have been found to raise “bad” LDL cholesterol and lower “good” HDL cholesterol, increase insulin resistance, and increase the risk of heart disease. Trans fats also produce inflammation in the body, which can contribute to heart disease, stroke, and diabetes. (3)

Incorporating Healthy Fats Into a Healthy Diet

The newest nutrition recommendations from the Dietary Guidelines for Americans recommend that 20-35% of an adult’s daily calories come from fat sources in the diet. The Dietary Guidelines also advise that less than 10% of an adult’s daily calories should come from saturated fat sources; The American Heart Association recommends further limitations to saturated fat intake and advises that only 5-6% of daily calories should come from saturated fat sources.(4,5) The Dietary Guidelines recommend limiting trans fats as much as possible. (5)

For every gram of fat in a food, there are 9 calories. This is more than double the amount of calories found in carbohydrates and protein, which contain 4 calories per gram. This is why portion control is key when eating foods that contain fat. Know the true size of portions.

One serving size of fat, equal to 5 grams of fat, is equal to:

  • ⅓ ounce of nuts
  • 2 tablespoons, or 1/8 of a medium-sized avocado
  • 2 teaspoons of a nut butter
  • 1 teaspoon of oil
  • 1 egg
  • 2-3 ounces of fatty fish
  • 1 tablespoon of ground flaxseed or sesame seeds
  • 3 tablespoons of sunflower seeds

If you eat 1,200 calories per day, 20 to 35% of your calories is about six to nine 5-gram servings of fat!

Take Home Message

Although it is true that too much fat in your diet can add excess calories and lead to weight gain, eating too much of any food can be unhealthy. Fat is a crucial component of a healthy, balanced diet. Choosing the right fat sources is also key - strive to eat more unsaturated fat sources to gain health benefits such as reduced inflammation, improved blood cholesterol levels, and decreased risk of developing heart disease.


  1. Dietary Fats. American Heart Association Website. Updated March 24, 2014.
  2. The truth about fats: the good, the bad, and the in-between. Harvard Health Publications- Harvard Medical School Website. Published February 2015. Updated August 22, 2017.
  3. Types of Fat. The Nutrition Source- Harvard T.H. Chan School of Public Health Website.
  4. Saturated Fat. American Heart Association Website. Reviewed 2015. Updated March 24, 2017.
  5. Dietary Guidelines 2015-2020. Chapter 1. Key Elements of Healthy Eating Patterns. Office of Disease Prevention and Health Promotion Website.


Melissa Lanes is a clinical nutrition specialist at Bariatric Specialists of North Carolina. Melissa is commissioned as a Registered Dietitian with the Academy of Nutrition and Dietetics and is a Licensed Dietitian/Nutritionist within the state of North Carolina. She is also a Certified Health Education Specialist. She is passionate about helping her patients live life to the fullest.