Fats play an important part in our daily diet. You need a small amount as part of a healthy balanced diet. Fat provides the body with energy, essential fatty acids and helps with the absorption of vitamin A, D, E and K. However, some types of fats, especially those found in processed foods, are not good for us. This Food Fact Sheet explains the different types of fat we eat, how they affect our health and how much we should be eating.
Fats are important, as they:
There are two main groups of fat – saturated and unsaturated. Foods tend to contain a mixture of both saturated and unsaturated fats but are classed with whichever type is the highest. For example, butter is classed as a saturated fat product, as it contains more than 50% saturated fat.
These types of fats are mainly found in animal products such as fat on meats, meat products, butter, ghee, lard, and dairy products including cheese.
Products made using these types of fats and combined with cereal products such as cakes, biscuits, pastries are also classed as foods high in saturated fat. Some vegetable fats are also high in saturated fat such as cocoa butter, palm, and coconut oil.
These are found generally in plant foods such as seeds, nuts, olives, and avocados. They can be either polyunsaturated such as sunflower, soya, corn, and sesame oils/spreads or monounsaturated such as olive and rapeseed oils/spreads.
These are a type of polyunsaturated fat and known as omega-3 and omega-6 fats. They cannot be produced by the body so a small amount is needed from your diet.
Oily fish is the best source of omega-3, such as sardines, salmon or mackerel. If eating fish, it should be from a sustainable source. Plant sources of omega-3 include walnuts, flaxseeds, linseeds or green leafy vegetables. Some food such as eggs or fish products may be fortified with omega-3.
Omega-6 are found in nuts, seeds and vegetable oils/spreads, such as rapeseed, corn, or sunflower.
Trans fats are found naturally present at low levels in some dairy foods and meats but are also found in processed & hardened vegetable oils. They can be found in ‘partially hydrogenated vegetable fats/oil’, which is often used by food manufacturers to help prolong shelf life. Products that contain trans fats include margarines, cakes, biscuits and fast foods. However, intake in the UK is now very low, due to UK Government recommendations for food manufacturers to reduce the amount of trans fat added to food.
High intake of saturated fats is associated with higher blood cholesterol levels. Reducing intake of saturated fat and replacing with a smaller amount of unsaturated fats may help to maintain normal blood cholesterol levels. This will have a positive impact on associated health conditions, such as reducing the risk of heart disease or stroke.
High intakes of fat are also associated with weight gain, which can increase the likelihood of developing problems such as type 2 diabetes, joint problems, and some cancers.
A third of our daily energy should come from fat, the majority of which should be unsaturated. This is approximately 70g fat per day for an adult female and 90g per day for an adult male.
Saturated fat intake should be no more than 10% of total daily energy (20g for an adult female and 30g for an adult male). Trans fat should be no more than 2% (5g) of our daily energy.
We should increase our intake of essential fatty acids, especially omega-3. The recommendation is to eat two portions of fish per week (from a sustainable source), one of which should be an oily fish. Plant-based sources, such as green leafy vegetables or walnuts contain small amounts.
All packaged food products must provide nutritional information on the label. This information helps us to make healthier choices. Nutrition panels on the back or side of a label will provide information per 100g and/or per portion, which means you can compare like-for-like products.
Some products will provide a traffic light summary on the front of pack.
Traffic lights for fat and saturated fat per 100g is shown below:
|
Low |
Medium |
High |
Fat |
3g or less |
3g to 17.5g |
17.5g or more |
Saturated fat |
1.5g or less |
1.5g to 5g |
5g or more |
A product which is ‘red’ should be eaten with caution and less often. We should be aiming to eat more green and amber products.
There are guidelines around nutritional claims such as ‘low in fat’:
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