Nutrition 101: Fats

Written By Katherine Basbaum, MS, RD, MyFitnessPal Food Data Curator 

Reviewed By Stephanie Nelson, MS, RD MyFitnessPal Sr. Lead Nutrition Scientist 

You may remember the low-fat/high-carb craze back in the 1990s. Butterless bagels were consumed with reckless abandon and reduced-fat cookies, crackers and chips occupied most of the prime real estate on grocery store shelves. Thankfully, more recent research has shown us that certain fats play a beneficial role in helping us achieve health and weight-loss goals.

What is fat, and why do we need it?

In addition to tasting good and giving foods moisture, fats are a dense energy source, helping to slow down digestion, which contributes to our feelings of satiety after a meal and slows the rate at which sugars from carbohydrates enter our bloodstream (1). Certain types of dietary fat can also improve our immune system, lower our risk for heart disease, help our bodies absorb important vitamins and help support brain function and development (1).

There are four main types of dietary fats: trans fats, saturated fats, monounsaturated fats (MUFAs) and polyunsaturated fats (PUFAs.) The structure of these fats is what makes them behave differently in the body, and ultimately determines how they impact our health. The unhealthier fats have a reputation for increasing our risk of chronic disease like heart disease, type 2 diabetes and obesity (2).

Here’s a brief rundown:

• Trans Fat Though it does occur naturally in some foods, most trans fats are synthetically made during food processing and come from partially hydrogenated oils (PHOs.) These fats became a very popular additive in the processed/packaged foods due to their ability to keep foods stable for longer periods, meaning they could last longer on supermarket shelves. Trans fats also make certain foods easier and faster to cook. The downside is that trans fats are by far the worst offenders when it comes to our health, with research showing that they not only increase “bad” LDL cholesterol but also lower “good” HDL cholesterol as well as increase the risk of type 2 diabetes and cancer (1) (2).  This is why, as of 2021 thanks to a ruling by the FDA, food manufacturers can no longer add PHOs (the major source of artificial trans fat) to foods (3). 
• Saturated Fat Mostly solid at room temperature, these unhealthy saturated fats are mainly found in animal-derived foods like red meat and full-fat dairy products like butter, cream, cheese or whole milk, but also in plant-derived coconut and palm oil. It’s important to watch our intake of these fats because these have been found to increase LDL cholesterol, a significant risk-factor for heart disease (4).  
• Mono- and Polyunsaturated Fats Also known as MUFAs and PUFAs, these fats are recognized for their potential health benefits. They’re found in many vegetable and fish-based foods like plant-based cooking oils (i.e. olive, canola, avocado, and grape seed), ground flaxseed, avocados, olives, nuts and seeds, and fatty fish like salmon or mackerel. These fats are liquid at room temperature and work together to moderate things like inflammation, blood clotting, muscle contractions, as well as improve blood cholesterol levels and protect against heart disease (1).

How much dietary fat do we need?

The recommended daily intake for fat is 20-35% of calories (5). Since we now know how important certain fats are in the diet, the goal should not be “the lower the better.” Rather, work towards having unsaturated fats make up the majority of the total fat in your diet. The 2020-2025 Dietary Guidelines for Americans recommends saturated fats make up less than 10 percent of calories per day starting at age 2 (6). 

Example: For someone eating 2000 calories per day, the recommendation would be about 600 of total daily calories coming from total fat (66 grams) and no more than 100 of total daily calories from saturated fat (~11 grams).

Which foods contain fat?

As you can see, dietary fat is present in a variety of foods. It is naturally present in meats, dairy and eggs as well as in plant foods like olive oil, avocados, nuts/nut butters and seeds. But it can also be found in high amounts in various packaged foods like sweets, baked goods, chips, crackers and frozen meals. Packaged foods like these tend to be high in fat and overall calories, while providing scarce other nutrients that are beneficial for health, so it’s best to consume fat from whole food sources.

Tracking fat intake in MyFitnessPal

The default fat goal in MyFitnessPal is 30% of calories from fat, and no more than 10% of calories coming from saturated fat. If you use MyFitnessPal to track your fat intake, keep an eye on the breakdown of the total fat you eat in a day that the app provides for you. The goal is to keep the saturated fats as low as possible and shoot for higher amounts of those protective, heart-healthy PUFAs and MUFAs!

References

1. Mahan LK, Escott-Stump S, Raymond JG, Krause MV. Krause’s Food & the Nutrition Care Process.; 2020. http://ci.nii.ac.jp/ncid/BB08090391.
2. Dhaka V, Gulia N, Ahlawat KS, Khatkar BS. Trans fats-sources, health risks and alternative approach - A review. J Food Sci Technol. 2011;48(5):534-541. doi:10.1007/s13197-010-0225-8
3. Program HF. Trans fat. U.S. Food And Drug Administration. https://www.fda.gov/food/food-additives-petitions/trans-fat. Published April 30, 2024.
4. Professional CCM. LDL cholesterol. Cleveland Clinic. https://my.clevelandclinic.org/health/articles/24391-ldl-cholesterol. Published February 7, 2025.
5. Dietary reference intakes for energy, carbohydrate, fiber, fat, fatty acids, cholesterol, protein, and amino acids.; 2005. doi:10.17226/10490

Snetselaar LG, De Jesus JM, DeSilva DM, Stoody EE. Dietary Guidelines for Americans, 2020–2025. Nutrition Today. 2021;56(6):287-295. doi:10.1097/nt.0000000000000512