Most experts agree that eating too much saturated fat increases health risks, such as the risk of cardiovascular disease. On the other hand, eating unsaturated fats as part of a nutritious, balanced diet may have health benefits.

Fat is an essential nutrient that the body needs to function fully. Fats in the diet help the body absorb vitamins and minerals and serve other vital roles. Fat stored in body tissues is critical for:

  • energy storage and metabolism
  • body temperature regulation
  • insulation of the vital organs

However, a diet with too much fat can increase body weight, along with a person’s risk of cardiovascular disease.

The Dietary Guidelines for Americans 2020 to 2025 recommends that adults get between 20% and 35% of their daily calories from fats. However, saturated fats should account for less than 10% of a person’s daily calorie intake.

The American Heart Association recommends eating less than 6% of total calories from saturated fat, which equates to 120 calories for someone eating 2,000 calories per day.

This article explains the differences between saturated and unsaturated fat, their roles in the body, and which foods provide them.

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The four main types of fats are:

Saturated and trans fats are solid at room temperature, whereas polyunsaturated and monounsaturated fats are liquid.

Most health organizations and dietary experts recommend eating saturated fats in moderation and replacing them with unsaturated fats when possible.

Saturated and trans fats increase LDL or “bad” cholesterol in the blood. Unsaturated fats help to lower LDL and protect the heart. High levels of LDL can lead to a buildup of plaque in the arteries, which increases the risk of heart disease and stroke.

Many foods contain a mixture of saturated and unsaturated fats, which can make eliminating one type difficult.

Over many decades, studies have found evidence of a link between saturated fats in the diet and increased risk of cardiovascular disease. However, recent research has challenged this link.

A 2019 review did not find any significant effects of reducing saturated fat on people’s risk of heart disease. Trans fats, however, did increase the risk.

Other studies have also reported no link between saturated fat intake and the risk of cardiovascular disease, but those studies may have serious flaws, which a 2022 article points out.

It is possible that a diet containing too many saturated fats can increase body weight and the risk of CVD, but it might not be as harmful as scientists once thought.

Some saturated fats may have more health benefits than others. For example, the lauric acid in coconut oil may help with digestion and metabolism. However, there is not enough evidence to recommend one saturated fat over another.

In contrast, the health benefits of unsaturated fats are well-established. The Mediterranean diet is the most well-researched dietary pattern, and many dietary recommendations are based on it.

The Mediterranean diet is based on an abundance of minimally processed plant foods, healthy fats, such as olive oil and nuts, whole grains, and a moderate amount of lean protein, such as poultry and oily fish. The diet is low in processed foods, saturated fats, and animal and dairy products.

People who eat this type of diet have a low rate of heart disease despite consuming a relatively high fat diet. Researchers believe that consuming polyunsaturated and monounsaturated fats instead of saturated fat is an important factor in the diet’s cardioprotective effects.

For example, extra virgin olive oil has anti-inflammatory properties and is rich in antioxidants. It helps lower blood pressure and LDL cholesterol, increase HDL, and improve blood sugar management.

The following sections provide examples of foods containing different types of foods.

Saturated fat

These fats have single bonds between their molecules and are “saturated” with hydrogen molecules. They tend to be solid at room temperature.

Food sources that contain high levels of saturated fat include meat and dairy products, such as:

Unsaturated fat

Unsaturated fats contain one or more double or triple bonds between the molecules. These fats are liquid at room temperature in oil form.

This group breaks down further into two categories: monounsaturated and polyunsaturated fats.

Dietary sources of unsaturated fats include:

  • avocados and avocado oil
  • olives and olive oil
  • peanut butter and peanut oil
  • vegetable oils, such as sunflower, corn, or canola
  • fatty fish, such as salmon and mackerel
  • nuts and seeds, such as almonds, peanuts, cashews, and sesame seeds

Trans fat

These fats take a liquid form that converts to solid fats during food processing techniques.

Since 2015, the Food and Drug Administration (FDA) has taken steps to eliminate partially hydrogenated oils (PHOs), a significant source of trans fats, from processed food. Manufacturers had until the beginning of 2020 to stop adding PHOs to their food products.

Cookies, crackers, doughnuts, and fried foods may still contain trans fats, but they are becoming less prevalent.

Nutrition resources

For more science-backed resources on nutrition, visit our dedicated hub.

Some tips for eating more heart-healthy fats and limiting saturated fats include:

  • Choose lean meats, such as chicken and turkey, instead of processed and fatty cuts.
  • Swap butter, margarine, or lard for olive oil or another plant-based oil.
  • Add nuts and seeds to meals, or eat them as snacks.
  • Aim for at least two portions of oily fish per week, such as tinned sardines and salmon.
  • Be cautious about foods that claim to be fat-free or low in fat. Many of these products contain added sugars and refined carbohydrates to replace the fats. These ingredients can increase caloric intake without any extra nutritional value.
  • Limit the intake of processed foods, as these may be high in trans fats and sodium.
  • Grill, bake, or steam foods instead of deep-frying them.

Despite the abundance of research on dietary fats, there are still questions regarding the relationship between saturated fats and adverse health outcomes, such as heart disease.

However, most experts agree that limiting the intake of most saturated fats and consuming plenty of unsaturated fats, such as plant oils, avocado, nuts, seeds, and fatty fish, has many health benefits.