You may have seen some bad press surrounding dietary fat, but how true is it? Fats are an important part of our diet, especially when it comes to absorbing other vital nutrients and helping our bodies function properly. The difficulty is that not all fats are created equal, and when it comes to unsaturated and saturated fats, there are a few things to consider.
In general, unsaturated fats like avocados, olive oil, nuts and seeds are the “good” fats we want to include in our diet. It helps support heart and brain health, among other functions. Saturated fat, on the other hand, should be eaten in moderation and excess is associated with negative health outcomes.
Next, we will explain the differences between unsaturated and saturated fats and their functions in the body. Also, if you’re looking for a nutritionally dense diet with plenty of healthy fats, our guide Mediterranean diet is a great place to start.
What are dietary fats?
Dietary fats is defined as the fat we consume with food, so it is different from body fat or blood triglycerides. It is one of the three macronutrients (protein, carbohydrates and fat) that our bodies need to function and function.
All fats contain nine calories per gram, but not all fats are as nutritious as others. Polyunsaturated fatty acids, especially omega-3 and omega-6 fatty acids, are necessary for proper brain and body function, while monounsaturated fats help absorb fat-soluble vitamins such as vitamins A, D, E, and K. Some fats, such as saturated fats and trans fats have been linked to negative health outcomes, including metabolic syndrome (a combination of obesity, diabetes and high blood pressure) and cancer.
What is saturated fat?
Saturated fats are single-linked carbon chains saturated with hydrogen atoms, meaning they are usually solid at room temperature. While the hydrogenation process turns unsaturated fats into saturated fats (trans fats) by forcing hydrogen into the empty carbon chain spaces, saturated fats are naturally like that. While excess saturated fat can have negative health consequences, a small amount of saturated fat is fine, so you don’t have to completely cut out your favorite foods to avoid it.
Dr Kevin Barrett, GP The new knee surgery (opens in a new tab) in Hertfordshire, UK, explains further: “We need to eat some fat because it is important for the absorption of fat-soluble vitamins A, D, E and K and is a source of essential fatty acids. Saturated fat in highly processed foods is associated with negative health outcomes, but fat from less processed foods does not have such strong links.
Some sources of saturated fat include:
- Fatty cuts of meat
- Processed meats such as sausages or bacon
- Butter, lard and fat
- Hard cheeses such as cheddar
- Cream and ice cream
- Cookies, cakes and pastries
- Savory snacks such as chips, crackers
- Fried foods
- Coconut oil
Excessive consumption of saturated fat is one of the main causes of obesity and related conditions in adults, according to a US study. International Journal of Molecular Sciences (opens in a new tab). With that in mind, it’s important to know how much saturated fat you’re consuming, as it’s estimated that 70% of Americans consume more than the recommended daily intake. USDA (opens in a new tab). On a 2,000-calorie diet, that equates to about 22g of saturated fat per day.
Dr. Deborah Lee, from Dr Fox Online Pharmacy (opens in a new tab), says that consuming too much saturated fat can cause heart problems. “In general, saturated fat is the ‘bad fat,'” she says. “These are fats we should all be eating less of.” They tend to be associated with elevated levels of bad cholesterol, which increases the risk of atherosclerosis (fatty plaque build-up in the arteries), which leads to heart disease, including heart attacks and strokes. In general, saturated fat should make up no more than 5-6% of your total daily calories.
What are unsaturated fats?
There are two types of unsaturated fats: monounsaturated and polyunsaturated. Unsaturated fats can promote the levels of “good” HDL cholesterol in your body and lower the levels of “bad” LDL cholesterol, which can build up in your veins and arteries and cause high blood pressure.
These fats come from plant sources and include:
- Olive and rapeseed oil
- Nuts, nut butters and nut oils
- Seeds, such as pumpkin or sesame seeds
in 2021 research done Nutrients (opens in a new tab) journal suggests that consumption of monounsaturated fatty acids may lead to positive cardiometabolic consequences. Another study Annals of the New York Academy of Sciences (opens in a new tab) also found that boosting HDL (good) cholesterol can also reduce inflammation in the body, giving it potentially cardioprotective properties. Because monounsaturated fats promote HDL (good) cholesterol, it’s important to make sure you’re getting enough to support your heart health.
These fats come from plant sources and include omega-3 and omega-6 fatty acids
Omega-3 sources include:
- Fatty fish such as mackerel and salmon
- Seeds such as flax seeds or chia seeds
- Nuts such as walnuts
- Legumes such as soybeans
“The omega-3 acids in oily fish are EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid),” explains Dr. Lee. “Although the human body can synthesize EPA and DHA, it is not efficient, which means that their levels are usually low. So it’s important to make sure you’re getting enough omega-3, both through food and omega-3 supplements. Omega-3 fatty acids are thought to help prevent heart disease by helping to lower blood triglycerides (fats), lower blood pressure, and improve circulation.
Sources of omega-6 include:
- Meat, fish and poultry
- Legumes such as soybeans
- Sunflower oil
“Omega-6 fatty acids are essential fatty acids obtained from food and used primarily for energy,” explains Dr. Lee. “The health benefits of omega-6 are not so clear. We recommend eating more omega-3 than omega-6. Omega-6 is found in, for example, meat, poultry, fish, eggs, soybean oil, corn oil, walnuts, almonds and cashews.
Review in magazine Biomedicine and pharmacotherapy (opens in a new tab) says that omega-3 and omega-6 should be consumed in balance. Omega-3s are used to build the structure of our cells and are important for your immune system to function properly. High levels of omega-6s may contribute to the development or worsening of cardiovascular disease, cancer, and inflammatory diseases, but when taken in combination with omega-3s, they lower harmful LDL cholesterol, increase protective HDL, and help improve insulin sensitivity.
Unsaturated and saturated fats: the right balance
The USDA guidelines (opens in a new tab) recommends that 20-35% of your total calories come from fat. This works out to about 44-77g per day on a 2000 calorie daily diet. Less than 10% of your daily calories should come from saturated fat, 15-20% from monounsaturated fat, and 5-10% from polyunsaturated fat.
Dr. Lee is a lawyer Mediterranean diet, because it is low in saturated fat and high in unsaturated fat. “It’s possible that eating less saturated fat and more unsaturated fat will increase your longevity,” she says. “People who lived in Greece and other Mediterranean countries, who always had a high intake of unsaturated fat, were found to have a lower risk of heart disease than those in other Western countries.
For the best quality fat, choose minimally processed liquid fat. For example, you should choose olive oil, which has been shown to have cardioprotective properties, over frying with butter. Also, finding healthier alternatives to unhealthy foods high in saturated fat can help you stay within your recommended daily allowance.
Some healthy swaps you can make include:
|Unhealthy fatty foods||Healthy alternatives|
|Fatty cuts of meat||Leaner meats such as chicken or fish|
|Processed meats such as sausages, bacon||Leaner meats such as chicken or fish (you can also get chicken sausages and turkey bacon, although these can be highly processed)|
|Cream or ice cream||Greek yogurt or sherbet|
|Hard cheeses such as Parmesan||Feta or cottage cheese|
|Butter, lard or fat||Olive oil, you can also use mashed banana or applesauce to replace fat when baking|
|Cookies, cakes and pastries||Fruit, granola, yogurt with honey|
|Chips and crackers||Nuts and seeds, kale chips, homemade vegetable or tofu chips|
This article is for informational purposes only and is not intended as medical advice.