Fats: Which ones can you eat?

We all need a certain amount of fat in our diet. Without it, we would miss out on a valuable source of energy for the body which is crucial for moving nutrients around the body, building cells and the absorption of fat soluble vitamins A, D and E and K.

Nutritionists agree that eating the right amount of the right type of fats is just as important as the total amount we eat.

How much fat should we be eating?

The average total fat intake is almost at the population target intake of 35 per cent of your total calorie intake.1 This equates to about 70g of fat a day for women and 95g of fat a day for men. But, there are different types of fat and you need to make sure that those ‘fat calories' count by eating more of some fats and less of others.

Which fat should we choose?

There are three main types of fat: saturated, polyunsaturated and monounsaturated. We need all three in our diets, but because some are better for us than others, it's important to become aware of the amount of which fats you are eating.

  • Saturated fats are naturally hard at room temperature and are found in the greatest quantities in animal products such as dairy, meats and manufactured goods such as cakes, biscuits and pies. Eaten in excess, saturated fats have been shown to raise levels of ‘bad' LDL cholesterol in the blood, one of the main contributors to heart disease
  • Trans fats occur naturally in foods such as meat and dairy products but are also formed when liquid oils are hydrogenated to make them solid – avoid these
  • Triglyceride are found in foods such as dairy products, meat and cooking oils. People who are very overweight, eat a lot of fatty and sugary foods or drink too much alcohol are more likely to have a high triglyceride level
  • Unsaturated fats of which there are two types, namely polyunsaturated and monounsaturated fat. These types of fats can actually reduce cholesterol levels and provide us with the essential fatty acids that the body needs
  • Polyunsaturated fats are ‘essential' because they cannot be made in the body and have to be provided by diet
  • Omega-6 polyunsaturates are mainly found in vegetable oils. Omega 6 fats reduce ‘bad' LDL cholesterol, but too much may also reduce the ‘good' HDL cholesterol2
  • Omega-3 polyunsaturates have now been shown to be particularly important in preventing heart disease and strokes. One of the ways these fatty acids are thought to be beneficial is by making the blood thinner. They also protect the heart against abnormal heart beats (arrhythmias) and help reduce triglyceride levels.3 Good sources are oily fish, as well as nuts and seeds, and their oils such as soya and walnut
  • Monounsaturated fats are most commonly found in olives, nuts, avocados, olive oil, rapeseed oil, groundnut oil and spreads made from them. Monounsaturated fats can lower ‘bad' LDL cholesterol but more importantly they do not affect the level of the protective HDL ‘good' cholesterol2

Key tips:

  • Eat at least two portions of fish per week, one of which should be oily (choose from salmon, mackerel, sardines, pilchards or herring)
  • Use lower fat versions of dairy products, e.g. semi-skimmed or skimmed milk, reduced fat cheese, or use less of the full fat products
  • Choose leaner meats (e.g. chicken and turkey) and remove visible fat and skin where possible. Swap some vegetables or pulses for meat in your cooking
  • Use less fat in cooking and use low fat spreads on toast and sandwiches
  • Grill, steam, boil and bake foods instead of frying or roasting
  • Check food labels to work out if a food is high or low in fat: High is more than 20g fat per 100g - Low is 3g fat or less per 100g

References:
1. Henderson L, Gregorgy J, Irving K et al (2003). The National Diet and Nutrition Survey: Adults aged 19-64 years, volume 2: Energy, protein, carbohydrate, fat and alcohol intake. HMSO, London.
2. Stanner S. Cardiovascular Disease: Diet, Nutrition and Emerging Risk Factors. The report of the British Nutrition Foundation. 2005. Blackwell Science.
3. Advisory Committee on Nutrition (SACN) and the Committee on Toxicity. Advice on fish consumption: benefits and risks. 2004.