What is the unhealthiest type of fat?

Fats explained

A small amount of fat is good for you. Too much bad (saturated) fat in your diet can increase your risk of developing heart and circulatory diseases.

There are lots of things you can do to eat less bad fats. Replacing some of them with healthy (unsaturated) fat will keep your heart healthy and manage your weight.

Why do we need some fat?

We all need to eat a small amount of fat to have a healthy and balanced diet. The right amount of fat helps our bodies to:

• stay warm
• have energy
• make hormones that help our bodies work the way they should
• have essential fatty acids like Omega-3 and Omega-6 – the body can’t make these
• absorb vitamins A, D and E – the body can’t absorb these vitamins without the help of fat.

When we eat more fat than our bodies need, the excess from our food is turned into body fat. We need some body fat to function properly and be physically active. But having too much body fat, especially around your waist, can increase your risk of developing heart and circulatory diseases. It can also make you feel more tired, give you joint pain and make you snore while you sleep.

Do you need help maintaining your weight?

Having a healthy weight can give you more energy and help you sleep better. It will also help to keep your heart healthy and reduce your risk of being seriously ill if you have coronavirus.

More than 3 in 5 people are living with extra weight or obesity in the UK. Our information hub is here to help. Find easy tips to lose weight gradually, simple recipes to fit around your routine and our 10 minute workout.

What are the types of fat?

There are four main types of fat in our diets. They are:

• monounsaturated fats
• polyunsaturated fats
• saturated fats
• trans fats.

Monounsaturated fat and polyunsaturated fat are ‘healthy’ fats. They can help to maintain healthy cholesterol levels. Cholesterol is a fatty substance in your blood.

Saturated fat and trans fat are ‘unhealthy’ fats. They can raise your ‘bad’ (non-HDL) cholesterol in your blood. Too much cholesterol can increase your risk of having:

Cutting down on foods and drinks that are high in saturated and trans fats will help to keep your heart healthy and maintain your weight. You can replace some of them with unsaturated fats.

Types of fats

Types of foods

Monounsaturated

Have these healthy fats in small amounts.

Peanut butter, almonds, cashews, hazelnuts, peanuts and pistachios.

Rapeseed oil, olive oil, olives and avocados.

Polyunsaturated

Have these healthy fats in small amounts.

They supply omega-3 and omega-6. Your body can’t make these important nutrients on its own.

Oily fish like kippers, mackerel and salmon.

Rapeseed oil, sunflower oil and corn oil.

Some nuts like walnuts, pine nuts, sesame seeds and sunflower seeds.

Saturated

Reduce how much you eat these unhealthy fats by swapping some of them for unsaturated fats.

Processed and fatty meats like sausages, ham, burgers and bacon.

Hard cheeses like cheddar. Whole milk, cream and ice cream. Butter, lard, ghee, suet, palm oil and coconut oil.

Trans

Limit how much you eat these unhealthy fats as much as you can.

Fried foods and takeaways.

Snacks like biscuits, cakes, pies and pastries.

Hard margarines made with hydrogenated oil.

How much fat should I eat?

The UK government recommends that:

• men should have less than 30g of saturated fat per day
• women should have less than 20g of saturated fat per day
• men and women should have less than 5g of trans fat per day
• children should have less trans fat and saturated fat per day than adults.

Most people in the UK eat too much saturated fat. The nutrition labels on your food’s packaging will show you the amount of total fat and saturated fat you are eating. Looking at the amount of saturated fat in your food will help you keep to the recommended daily intake.

We tend to eat more saturated fats than trans fats. But you may want to check your food’s nutrition labels for trans fats. They are usually listed as ‘hydrogenated fats’ or ‘hydrogenated vegetable oils’ in the ingredients.

Worried about your diet?

It can be confusing to understand what fat does to your body and how much you should eat. Watch our 3 minute video to learn about healthy fats, unhealthy fats and which foods contain them.

Are ‘low fat’ and ‘lighter’ foods better for me?

A lower fat option might not be better for you. For a food or drink to be labelled as:

• ‘lite’, ‘light’ or ‘lighter’, it must have at least 30 per cent less fat than the original product
• ‘low fat’ or ‘reduced fat’, it must have less than 3g of fat per 100g and the pack’s label will have the fat content coloured green.

Sometimes, the fat will be replaced with more sugar or salt to make it taste like the original product. This might not make the lower fat option healthier.

Even if your food’s packaging says it’s lower fat, you might want to check its nutrition label. You can check the amount of ‘total fat’ and the amount of ‘saturated fat’ per serving on the label.

Easy tips to help you reduce unhealthy fats

• Cook with vegetable oils and spreads like olive oil, rapeseed oil and sunflower oil.
• Measure the amount of oil you use with a teaspoon or use a spray bottle.
• Make your sandwich fillers healthier by using spreads made from vegetable oils and nuts. And swap hard cheese and processed meat for oily fish and vegetables like avocado, and lettuce.
• Reduce your intake of processed meats like hamburgers and sausages. Choose lean meats (meats with less fat) like skinless chicken, turkey and fish. Or plant-based protein like lentils, beans or Quorn.
• Snack on unsalted nuts and fruit, rather than biscuits, cakes and crisps. Or make your own healthy snacks like homemade fresh fruit scones.
• Use semi-skimmed, skimmed or 1% milk. Or no added sugar, plant-based milk like almond milk, soya milk, oat milk and cashew milk.
• Use lower fat cheeses like feta, mozzarella, half-fat cheddar, edam and ricotta, rather than cheeses like halloumi and cheddar. Or grate your cheese to make it go further in your meal.
• Check the amount of saturated fat per serving on your foods labels to help you keep to the recommended daily intake.

Try our easy recipes

Our recipe finder will help you take the stress out of planning yours and your family’s meals. Find quick recipes for meals and snacks to reduce the amount of saturated fat you eat. You’ll find tasty ideas for all dietary requirements and cuisines, even recipes to support diabetes, high cholesterol and high blood pressure.

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Page last reviewed: September 2021
Next review due: September 2024

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The Best And Worst Fats For Heart Health

Confused about which fats you should consume, and how much? Here’s the lowdown on the heart-healthiest options.

Wendy Haaf Updated February 20, 2018

For years, experts touted a low-fat diet as the key to reducing the risk of heart disease, but we now know that was misguided. The key is choosing healthier varieties of fats — such as the ones found in nuts and olive oil — and using them to curb your appetite, and crowd out calories from refined carbohydrates. We talked to the experts to find out how much fat you should be eating, which types are best, and how to use them.

Good: Monounsaturated fats

Found in: Olive, canola, peanut and sesame oils; avocados, almonds, and non-hydrogenated tub margarines.

Monounsaturated fat improves cholesterol levels, and may play a role in blood sugar control as well. Extra-virgin olive oil (EVOO) has even greater benefits than the regular variety, says Rosie Schwartz, a Toronto dietitian and author of The Enlightened Eater’s Whole Foods Guide — not only is it richer in cholesterol-lowering compounds called polyphenols, it contains a substance that helps prevent blood clots in much the same way as Aspirin.

How to use: When it comes to oil, olive, canola and peanut are good all-purpose options. And while EVOO is a delicious alternative to butter on bread, as well as a tasty base for dressings, you can fry with it, too. “The smoke point is higher than people think,” says Schwartz, “and in fact, in the Mediterranean, that’s what they use.” EVOO and sesame oil (which you can sprinkle on vegetables, or add to stir fry sauces) should both be stored in a cool, dark cupboard.

And here’s a trick if you’re shopping for tub margarine: Find the nutrition facts table, and add up the numbers for the ‘un’ fats (polyunsaturated and monounsaturated): if the answer is six or more, it’s heart-healthy.

Good: Polyunsaturated fats

Found in: Fatty fish, canola, safflower, sunflower, and flax-seed oils.

Polyunsaturated fats lower levels of damaging LDL cholesterol and triglycerides, and one type — omega 3s — may also help prevent the formation of stroke- and heart-attack-causing blood clots. The main polyunsaturated fat in vegetable oils, however, is a type called omega-6. (All oils are a mixture of different fats — including saturated — in varying proportions.) It may be a good idea to choose oils that contain only moderate amounts of omega-6, since some evidence suggests too much omega-6 may promote the simmering inflammation that’s linked with an increased risk of heart disease. Oils with a higher percentage of omega-6 include corn, cottonseed and soybean (all commonly used in prepared and packaged foods), while plant sources of omega-3 include flaxseed, canola, walnuts, pecans and pine nuts.

How to use: Canola, safflower and sunflower are all good options for baking, roasting, sautéing, and frying, though canola is the best when it comes to fat profile. (Mind you, no matter which fat you use, fried foods should only make up a very small part of your diet.) Drizzle walnut or flaxseed oil (which need to be stored in the fridge) onto salads or into yogurt or cereal to add a nutty flavour.

Bad: Saturated Fats

Found in: Meat, dairy products, palm and coconut oils, and hard margarines.

This type of fat raises LDL cholesterol, so it’s a good idea to eat it sparingly, but that doesn’t mean you need to cut out certain types of food entirely. For example, if you can’t bear to give up butter, “maybe you want to cut down on red meat, or choose lower-fat dairy products,” suggests Carol Dombrow, a registered dietitian and nutrition consultant for the Heart and Stroke Foundation. What else you’re eating is also important, stresses Schwartz — for example, the saturated fat in tropical oils such as palm and coconut may be less of a concern for vegetarians.

Worst: Trans Fats

Found in: Commercially baked and fried foods, many packaged foods, lard, and shortening.

When it comes to fats and heart disease risk, “trans fats are certainly the worst,” says Dombrow. Gram for gram, these fats are five times more harmful than saturated fats, driving up blood levels of unhealthy LDL cholesterol and triglycerides, and lowering ‘healthy’ HDL. The good news? Plans are under way to ban them in Canada beginning in September 2018.

How much (good) fat should you consume?

“It depends on the individual,” says Schwartz. “Moderation is really important — eating foods swimming in oil is still not a good idea, but 35 to 40 percent of total calories is likely fine, with a maximum of 10 percent from saturated fats.” For a woman who needs 1,500 calories per day, that translates to roughly 4.5 to 5.5 tablespoons — but remember, that’s from all sources, including foods such as nuts, peanut butter, dairy products and avocados.

This Is the Worst Kind of Fat for Your Heart

A s confusing as the diet message can be at times, one thing is clear. There are good fats and bad fats in the foods we eat, and some can really wreak havoc on the heart and its delicate vessels.

In a study published in the BMJ, scientists say that trans fats are linked to the highest rates of death from all causes, deaths from heart disease and heart problems. The trans fat risk surpassed even that associated with saturated fat, which is found in formerly taboo-for-the-heart foods like butter, eggs and red meat.

Russell de Souza, a dietician and epidemiologist from McMaster University, and his colleagues sifted through the published studies involving hundreds of thousands of participants on trans and saturated fats and their health effects. They found that those eating more trans fats had a 34% higher rate of dying from any cause compared to those eating less, a 28% higher risk of dying from heart disease, and a 21% greater risk of having heart-related health issues.

In contrast, eating saturated fat was not linked to a higher risk of early death, heart-related problems, stroke, or type 2 diabetes.

That doesn’t mean, however, that saturated fats now get a green light. de Souza points out that many people who try to cut back on saturated fats tend to substitute them with less healthy fats like those from margarine or with carbohydrates, which can contribute to heart disease. So while saturated fats when compared to trans fats did not substantially increase heart disease risk, that doesn’t mean saturated fats are actually heart healthy. It’s just that in the hierarchy of heart-friendly fats, trans fats are the worst and saturated fats are the next worst. “We didn’t find any evidence for increasing the allowable amount of saturated fat in the diet,” says de Souza.

The group that showed the lowest risk of early death or heart disease were those who consumed the most vegetable oils such as olive and canola. “If there is one message to go away with from these results, it’s that substituting saturated and trans fats with whole grains and vegetable oils is a step in the right direction,” says de Souza.

The results, he says, support current dietary guidelines for how much of different types of fats people should eat to maintain healthy hearts and lower their risk of chronic diseases. For now, he says, the advice to consume no more than 10% of daily calories in saturated fat and to limit trans fats to less than 1% of calories, is reasonable.

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