Monounsaturated fats, such as those found in olive oil, avocados, and certain nuts, are healthy fats. The benefits may include helping with weight loss, reducing the risk of heart disease, and more
Monounsaturated fats have several health benefits. They can help with weight loss, reduce the risk of heart disease, decrease inflammation and your risk of inflammatory conditions, and improve insulin sensitivity.
What are monounsaturated fats?
Monounsaturated fats are otherwise known as the “good” or “healthy” fats.
Types of monounsaturated fatty acids (MUFAs) include:
- oleic acid
- palmitoleic acid
- vaccenic acid
Many foods are high in healthy unsaturated fats, including mono- and polyunsaturated fats. Most consist of a combination of different fats — both healthy and unhealthy. Few foods contain only one type of fat.
Foods containing unsaturated fats are typically liquid at room temperature (think: olive oil). Those high in saturated fats are typically solid at room temperature (think: butter).
These different fats affect health and disease differently.
Monounsaturated fats may help with weight loss
All fats provide the same amount of energy — 9 calories per gram (g).
Changing the amount of fat in your diet can be an effective way to reduce your calorie intake and lose weight.
A diet with moderate amounts of monounsaturated fats may still help with weight loss if you’re in a calorie deficit.
For diets moderately high in carbohydrates, swapping saturated fats for monounsaturated fats may:
- burn more fat
- reduce body fat, abdominal fat in particular
Monounsaturated fats may reduce the risk of heart disease
Evidence suggests that increasing MUFAs in your diet can reduce your risk of heart disease, especially if you’re replacing saturated fat.
The American Heart Association recommends replacing saturated and trans fats with unsaturated fats as part of its dietary guidelines to improve heart health.
Monounsaturated fats can help lower your risk of heart disease and stroke by:
- reducing your levels of low-density lipoprotein (LDL) “bad” cholesterol
- increasing your levels of high-density lipoprotein-C (HDL-C) “good” cholesterol
Lots of research supports the benefits of the Mediterranean diet for heart health, of which monounsaturated fat from olive oil is a big component. Other aspects of this dietary pattern may also support heart health.
A 2022 systematic review of randomized controlled trials suggests that MUFA-rich food may help control your blood lipid levels, but more research is necessary to confirm these findings.
Talk with your doctor or a registered dietitian about ways to change your diet to lower your risk of heart disease.
Monounsaturated fats may reduce cancer risk
Some studies examining the role of high MUFA diets show a protective effect, some show no effect, and others show a harmful effect.
A 2020 systematic review suggests that the MUFA oleic acid — the most abundant in olive oil — may lower cancer risk and have a protective effect against cancer.
But another 2020 study shows that MUFAs may have growth-stimulating effects on kidney cancer cells.
Yet another study found that some unsaturated fatty acids, including MUFAs in olive oil, may decrease the risk of digestive cancer.
Olive oil also contains many anti-inflammatory compounds and antioxidants that may counteract the cancer cell growth effect and cause the protective effect rather than the MUFAs themselves.
Studies looking at prostate cancer risk and MUFAs are inconclusive. A 2018 cohort study found that increased intake of MUFA was associated with an increased risk of prostate cancer.
But another cohort study found no evidence that dietary intake of individual fatty acids was associated with an increased risk of prostate cancer.
Many recent studies on the association between cancer and MUFAs are observational, meaning they can’t prove cause and effect. Other components of diet and lifestyle may be contributing to a beneficial effect.
Monounsaturated fats may improve insulin sensitivity
Insulin is a hormone that controls your blood sugar by moving sugars from the blood into your cells. Insulin production is important for preventing high blood sugar and type 2 diabetes.
A 2023 study shows that avocado intake may be associated with better blood sugar regulation among people with diabetes.
Other research also suggests an association between a high dietary intake of unsaturated fatty acid and improved insulin resistance, particularly in:
- older adults
- females
- people with obesity
- those without hypercholesterolemia (high cholesterol)
Compared to polyunsaturated fats, monounsaturated fat may be the preferred fat for fasting insulin and if you’re trying to lower your glucose levels.
Monounsaturated fats may reduce inflammation
Inflammation is an immune system process that helps your body fight infection.
Sometimes inflammation happens slowly over a long time, which can contribute to chronic metabolic diseases like:
- obesity
- type 2 diabetes
- metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as nonalcoholic fatty liver disease (NAFLD)
- heart disease
Swapping saturated fats for unsaturated fats may help with inflammation related to these conditions and reduce your risk of chronic diseases.
Compared to other diets, such as high saturated fat diets and Western diets, high MUFA diets like the Mediteranean diet may reduce inflammation.
A 2020 study on mice found that when raised on a MUFA-rich diet for 15 weeks, the mice had lower levels of pro-inflammatory markers and higher levels of anti-inflammatory markers.
Which foods contain monounsaturated fats?
Plant- and animal-based foods both contain some MUFAs. Fatty fish like salmon are another good source.
Some evidence suggests that plant-based sources of MUFAs are more desirable than animal-based sources relative to the risk of coronary heart disease.
This may be due to the additional saturated fatty acids in red and processed animal meat.
Here’s a list of 11 foods high in MUFAs:
- Extra virgin olive oil: 9.8 g in 1 tablespoon
- Raw almonds: 10.4 g in 1 ounce
- Dry roasted, unsalted cashews: 9.1 g in 1 oz
- Raw Virgina peanuts: 8.5 g in 1 oz
- Pistachios: 7.8 g in 1 oz
- Green olives: 11.3 g in 100 g
- Pumpkin seeds: 20.9 g in 1 cup (129 g)
- Ground pork: 7.9 g in 3 oz (85 g)
- Avocados: 19.7 g in 1 avocado (201 g)
- Sunflower seeds: 25.9 g in 1 cup (140 g)
- Hard-boiled eggs: 2.04 g in 1 large egg
The takeaway
Monounsaturated fats are healthy fats most commonly found in olive oil, avocados, nuts, seeds, and some meat.
Diets high in monounsaturated fats can help with weight loss and may reduce risk factors for heart disease and promote heart health — as long as they don’t add extra calories.
Foods that contain MUFAs, especially olive oil, may also help reduce cancer risk, inflammation and risk of inflammatory conditions, and insulin resistance.
Although it is also important to eat other types of fat, replacing unhealthy fats with MUFAs can provide many health benefits.