A diet that is generally low in fat can help you to lose weight, or to maintain a healthy weight. Maintaining a healthy weight will reduce your risk of heart disease and stroke, diabetes and certain types of cancer. There are other conditions in which a low-fat diet is of use, such as gallstones.
Is fat bad for me?
For several decades, the standard advice to people who want to lose weight has been to eat a low-fat diet. Certainly, a diet which is low in fat because it is high in fruits and vegetables as well as fibre from whole grains is likely to be a healthy one, and this is the basis of many weight loss programmes such as Weightwatchers® and Slimming World®.
However, there is a growing body of evidence which suggests that a diet high in carbohydrates, particularly sugar, is a common trigger for obesity in many individuals, and that eating fat is not what makes us gain weight. In this case, a low carbohydrate diet such as the Atkins Diet is also an effective way of losing weight.
In studies in which low-fat and low-carbohydrate diets have been compared, both have been found to be effective, and individuals should find an eating pattern that works well for them, taking into account their lifestyle and what sort of foods they like.
The current advice about healthy eating from the British Nutrition Foundation, the NHS and the American Medical Association remains centred on meals based around starchy carbohydrates such as bread, rice or pasta, with fat representing a very small part of the food intake.This may change over the coming years if the advice about losing weight by cutting down carbohydrates becomes more well established.
Fat content of various foods
The following table is just a rough guide to which foods are higher or lower in fat. Different brands may vary in their fat content - get into the habit of looking at labels when you shop and learn which brands are lower in fat. Fat consumption will also depend on portion size.
|Food type||Low-fat foods||Medium-fat foods||Higher-fat foods|
|Cereal foods||Bread and flour, oats, breakfast cereals, rice and pasta are all low in fat but the higher-fibre varieties have other benefits too.||Plain biscuits.|
Plain or fruit scones.
Most cakes and biscuits.
|Fruit, vegetables and nuts||All fresh, frozen or tinned vegetables and fruit.|
Dried beans and lentils.
Baked or boiled potatoes.
Oven chips are lower in fat than fried chips.
Fried or roast potatoes.
Fried, creamed, buttered or cheesed vegetables.
Crisps and potato snacks.
|Fish||All white fish.|
|Oily fish such as tuna (fresh, not tinned), herring, mackerel, sardines, kippers, pilchards, or salmon. These contain healthy omega-3 fats.||Fish roe.|
|Meat||Lean white meat such as chicken and turkey breast (without skin).||Lean ham, beef, pork and lamb.|
Liver and kidney.
|Visible fat on meat.|
Meat pies and pasties.
|Eggs, dairy foods||Skimmed or semi-skimmed milk.|
Cottage or curd cheese.
Most hard cheeses.
|Fats and spreads||None.||Low-fat spreads.|
Margarine high in polyunsaturates.
Corn oil, sunflower oil and olive oil.
Dripping and lard.
Margarine not high in polyunsaturates.
|Drinks and soups||Tea and coffee.|
|Packet soups.||Cream soups.|
Low-fat diets and weight loss or weight maintenance
Energy in food is measured in calories (also known as kcal). If you want to lose weight, you need to eat fewer calories per day than you burn off in exercise. Foods which are high in fat contain a lot of calories, so cutting down on fatty foods is one way of losing weight. Very sugary foods also contain quite a lot of calories, but fat contains about twice as many calories as sugar per 100 g.
More about fats
Not all fat is bad. Although all fats are high in calories, we need some fat in our diet. Some types of fat are actually good for our health and some vitamins are dissolved in fat, so a low-fat diet may be lacking in these.
The different types of fat include the following:
These are mainly found in animal products such as the fat on meat, in lard, and the fat in dairy products such as butter, full-cream milk, etc. Meat and dairy products have a useful role in a healthy diet; however, try to avoid the fattier cuts of meat and use semi-skimmed or skimmed milk if you are trying to cut down on fat. Eating less saturated fat may reduce your risk of having a heart attack.
Some cheeses are high in fat, particularly cream cheese and hard cheeses such as Cheddar and parmesan. But you may find that a smaller portion of a more strong-tasting cheese is more satisfying than a larger amount of softer cheese which may be lower in fat.
These are oils which have come from vegetables but have been processed to make them hard, so that they are easier to use in food. They are often used in processed foods, and in commercially made cakes, biscuits and pastries. Food labels may call them partially hydrogenated oils. Trans fats are generally bad for you and there is no place for them in a healthy diet.
These mainly come from vegetables, nuts and fruits. They are divided into:
- Polyunsaturated fats, such as sunflower oil and corn oil.
- Mono-unsaturated fats, such as olive oil and rapeseed oil.
- Omega-3 fatty acids. These come mainly from oily fish such as pilchards, sardines, salmon, mackerel and fresh (not tinned) tuna. Omega-3 fatty acids are also present in some nuts and seeds, especially linseeds.
Omega-3 fatty acids may help prevent heart disease and improve our health in other ways.
Unsaturated fats contain as many calories as saturated fats, but can form part of a healthy diet. If you are trying to lose weight, make sure that you are not eating too much unsaturated fat.
Foods that contain fat often contain a mixture of saturated and unsaturated fats. Food labels often list the amounts of each type of fat in the food (or at least how much of the fat in the food is saturated). As a rule, we should aim to limit our intake of saturated fats and, when we use fats and oils, mainly choose those high in unsaturates. Food labels also show how many calories are in the food. So, it may be a good idea to get into the habit of reading food labels when you shop.