How Much Fat?

By Dietitian, Juliette Kellow BSc RD

Q: Even though I’m now at my target weight, I rarely eat above 25g fat each day apart from on special occasions. Is it harmful to not eat enough fat?

A: Assuming you’re having around 2,000 calories a day to keep your weight steady, consuming just 25g of fat a day means that only 11% of those calories are coming from fat – and this is actually very low. The Department of Health recommends that no more than a third of calories come from this nutrient, while most weight loss plans rarely recommend less than 20% of calories come from fat.

We all need some fat in our diets. In fact, it’s virtually impossible to have a fat-free diet as most foods, even fruit and veg, provide small amounts of fat. As well as providing the body with a concentrated source of energy, certain components of fat are essential parts of our body cells and are needed to make hormones. Fat also helps to insulate our body and small amounts around the major organs have a protective effect. Several vitamins (vitamins A, D, E and K) are also fat-soluble and tend to be found in foods with a high fat content. Very low fat intakes mean that intakes of these vitamins, in turn, are often extremely low, too.

Furthermore, two fatty acids – linoleic acid (omega-6s) and linolenic acid (omega-3s) – cannot be made by the body and so must be supplied in the diet. These fatty acids, known as essential fatty acids, are needed in small amounts for many functions in the body such as growth and healthy skin, as well as protecting against certain diseases. Vegetable, nut and seed oils tend to be good sources of omega-6 fats, while oily fish is a great source of omega-3 fats, needed to prevent blood clotting, thereby lowering the risk of stroke and heart disease.

In view of all these beneficial effects, I suggest you slightly increase your intake of fat. To stick within healthy eating guidelines, you should have no more than 70g fat a day if you’re having around 2,000 calories daily. But rather than eating more high-fat foods like crisps, biscuits, cakes and fried food, you should choose foods which contain the right sort of fat and are also packed with nutrients. Good choices include oily fish such as salmon, mackerel, sardines and trout, avocado, olive oil, fresh nuts and seeds. In practical terms, this might mean having an avocado dip for lunch with a wholemeal pitta bread and vegetable crudités, serving a grilled salmon steak for dinner or adding a handful of chopped almonds to your breakfast cereal.