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What are trans fats?

Artificial trans fats can be formed when oil goes through a process called hydrogenation, which makes the oil more solid (known as hardening). This type of fat, known as hydrogenated fat, can be used for frying or as an ingredient in processed foods.

Artificial trans fats can be found in some processed foods such as biscuits and cakes, where they are sometimes used to help give products a longer shelf life. However, in recent years many food manufacturers have removed trans fats from their products.

Trans fats can also be found naturally in some foods at low levels, such as those from animals, including meat and dairy products.

Are trans fats bad for you?

Consuming a diet high in trans fats can lead to high cholesterol levels in the blood, which can cause health conditions such as heart diseaseheart attacks and strokes. However, most people in the UK don't eat a lot of trans fats.

We eat about half the recommended maximum of trans fats on average, which is why the more commonly eaten saturated fat is considered a bigger health risk. For more information, see Is saturated fat bad for me?

Reducing your intake of trans fats

If you want to reduce your intake of trans fats, you should:

  • avoid products that list partially hydrogenated fat or oil on the label
  • include lots of fruit and vegetables in your diet
  • use fat-free or low-fat dairy products
  • try to eat fewer biscuits, cakes and pastries
  • use liquid vegetable oil for frying at home
  • when eating out, try to eat fewer fried foods

Further information:

Page last reviewed: 13/03/2015

Next review due: 12/03/2017