A healthy diet may help to prevent certain chronic (long-term) diseases such as heart disease, stroke and diabetes. It may also help to reduce your risk of developing some cancers and help you to keep a healthy weight. This leaflet explains the principles of a healthy diet. It is general advice for most people. The advice may be different for certain groups of people, including pregnant women, people with certain health problems or those with special dietary requirements.
A note about the different food groups
Your body needs energy to work normally and keep you alive. You get this energy from nutrients in the food that you eat - mostly, carbohydrates, fats and proteins. Minerals and vitamins are other nutrients that are also important in your diet to help your body stay healthy.
It is important to get the right balance between these different nutrients to get maximum health benefits (see below). Your diet should contain food from each of the following food groups:
- Starchy foods such as bread, rice, potatoes, pasta, etc.
- Fruit and vegetables.
- Milk and dairy foods.
- Protein foods. These include meat, fish, eggs and other non-dairy sources of protein (including nuts, tofu, beans, pulses, etc).
Fatty and sugary foods are the fifth food group that you eat. However, only a small amount of what you eat should be made up from fatty and sugary foods. In addition to the above, plenty of fibre and water in your diet is also important for your health.
What are the benefits of a healthy diet?
A healthy diet may help to prevent certain serious diseases such as heart disease, stroke and diabetes. It may also help to reduce your risk of developing some cancers. If you become sick, eating a healthy diet may help you to recover more quickly. Also, a main way of preventing obesity and overweight is to eat a healthy diet. If you are overweight or obese, eating a healthy diet can help you lose weight.
What makes up a healthy diet?
As a general rule, starchy foods and fruit and vegetables should provide the bulk of most of your meals. About one third of your diet should be made up from starchy foods and about one third from fruit and vegetables. The remaining one third of your diet should be made up from milk and dairy foods and protein foods. As mentioned above, you should limit the amount of foods and drinks that are high in fat or sugar.
Below, the principles of a healthy diet are explained. It is general advice for most people. If you have a specific health problem, or specific dietary requirements, this advice may not apply to you. If in doubt, you should check with your doctor. There are also some changes that pregnant women need to make to their diet. See separate leaflet called 'Pregnancy - Planning to Become Pregnant' for more details.
Eat plenty of starchy foods (complex carbohydrates)
As mentioned above, starchy foods such as bread, breakfast cereals, potatoes, rice, and pasta, together with fruit and vegetables, should provide the bulk of most meals. Some people wrongly think that starchy foods are fattening. In fact, they contain about half the calories of the same weight of fat. (However, it is easy to add fat to some starchy foods. For example, by adding butter to jacket potatoes or bread, or by adding oil to potatoes to make chips, etc.)
Carbohydrate is an important energy source for your body. Starchy foods often contain a lot of fibre (roughage). When you eat starchy foods, you get a feeling of fullness (satiety) which helps to control appetite. They also contain other vitamins and minerals important for health.
Tips to increase starchy foods include the following:
- For most meals, include a portion of, for example, rice, pasta, baked potatoes, or bread.
- For more fibre, choose wholemeal bread, brown rice or wholemeal pasta. When baking, use wholemeal flour.
- If you have cereals for breakfast, choose porridge, high-fibre cereals, or whole grain cereals (without sugar coating).
- Have tea breads, and plain or fruit scones, instead of sugary cakes and biscuits.
Eat plenty of fruit and vegetables
It is recommended that we eat at least five portions of a variety of fruit or vegetables each day. If you eat a lot of fruit and vegetables, then your chances of developing heart disease, a stroke, or bowel cancer are reduced. In addition, fruit and vegetables:
- Contain lots of fibre which helps to keep your bowels healthy. Problems such as constipation and diverticular disease are less likely to develop.
- Contain plenty of vitamins and minerals, which are needed to keep you healthy.
- Are naturally low in fat.
- Are filling but are low in calories.
One portion of fruit or vegetables is roughly equivalent to one of the following:
- One large fruit such as an apple, pear, banana, orange, or a large slice of melon or pineapple.
- Two smaller fruits such as plums, kiwis, satsumas, clementines, etc.
- One cup (or a handful) of small fruits such as grapes, strawberries, raspberries, cherries, etc.
- Two large tablespoons of fruit salad, stewed or canned fruit in natural juices.
- One tablespoon of dried fruit.
- One glass of fresh fruit juice (150 ml).
- About three heaped tablespoons of any vegetable.
- One dessert bowl of salad.
Some tips on how to increase fruit and vegetables in your diet include:
- Try some different types that you have not tried before. The variety of tastes and textures may be surprising. Juices, frozen, canned, and dried varieties all count.
- Try adding chopped bananas, apples, or other fruits to breakfast cereals.
- Aim to include at least two different vegetables with most main meals. Do not overboil vegetables. Steaming, stir-frying, or lightly boiling are best to retain the nutrients.
- Try always to have fruit or fruit juice with a meal.
- Try new recipes which include fruit. For example, some curries or stews include fruit such as dried apricots. Have fruit-based puddings. Fruit with yoghurt is a common favourite.
- How about cherry tomatoes, carrot sticks, dried apricots, or other fruits as part of packed lunches?
- Fruit is great for snacks. Encourage children to snack with fruit rather than with sweets.
Eat plenty of fibre (roughage)
Fibre is the part of food that is not digested. It is filling, but has few calories. It helps your bowels to move regularly, which reduces constipation and other bowel problems. Fibre may also help to lower your cholesterol level.
Starchy foods, and fruit and vegetables contain the most fibre. So the tips above on starchy foods and fruit and vegetables will also increase fibre. If you switch to wholemeal rice and pasta, and wholemeal bread, this can significantly increase your fibre intake. Pulses like lentils and beans are also full of fibre.
Have plenty to drink when you eat a high-fibre diet (at least 6-8 cups of fluid a day).
Eat enough milk and dairy foods
Milk and other dairy foods such as cheese and yoghurt are important in your diet as they provide calcium which is needed for healthy teeth and bones. They are also a source of protein and can provide other vitamins and minerals important for your health. Calcium-enriched soya milk and fromage frais also come under 'milk and dairy foods'. However, other foods such as butter and cream are not considered as dairy foods here as they are also high in fat, so they come under the fatty foods group.
To make sure that you get enough calcium in your diet, you need three servings a day from this food group. One serving is:
- 200 mls of milk.
- A small (150 g) pot of yogurt.
- A 30 g serving of cheese (about the size of a matchbox).
As the fat content of dairy foods can vary, make sure that you go for lower-fat options where possible, such as skimmed or semi-skimmed milk, low-fat cheese and low-fat yoghurt.
Eat other protein foods in moderation
Other protein-containing foods include meat, fish, eggs and non-dairy sources of protein. Non-dairy sources of protein include nuts, tofu, beans such as red kidney beans and canned beans, and pulses such as lentils and chickpeas.
You need a certain amount of protein to keep healthy. Protein is important for energy and for growth and repair in your body. Some of these high-protein foods can also be a source of iron and vitamins, including B vitamins and vitamin D. However, most people eat more protein than is necessary. Beware, some meats are also high in fat. Choose poultry such as chicken, or lean meat. Also, be careful, as many meat-based recipes include creamy or fatty sauces which are high in calories. When eating eggs, boil or poach them instead of frying. One portion of beans or pulses such as chickpeas or lentils is three heaped tablespoons.
There is some evidence that eating oily fish helps to protect against heart disease. Oily fish include: herring, sardines, mackerel, salmon, fresh tuna (not tinned), kippers, pilchards, trout, whitebait, anchovies and swordfish. It is thought that omega-3 fatty acids in the fish oil help to reduce the build-up of atheroma (furring of the arteries) which causes angina and heart attacks. Aim to eat at least two portions of fish per week, one of which should be oily.
Don't eat too much fat
You do need some fat in your diet but you need to be careful about how much fat you eat and what type of fat you eat. A low-fat diet helps to reduce your chance of developing diseases such as heart disease and stroke. It will also help you to keep a healthy weight. You should not have much saturated fats such as butter, lard, dripping, and unspecified margarine. Unsaturated fats are better, such as sunflower oil, olive oil, and low-fat spreads. Tips to reduce fat in your diet include the following:
- Whenever possible, do not fry food. It is better to grill, bake, poach, barbecue, or boil food. If you do fry, use unsaturated oil. Drain the oil off the food before eating.
- Choose lean cuts of meat, and cut off any excess fat.
- Avoid adding unnecessary fat to food. For example, use low-fat spreads, spread less butter or margarine on bread, measure out small portions of oil for cooking, etc.
- Watch out for hidden fats that are in pastries, chocolate, cakes, and biscuits.
- Have low-fat milk, cheeses, yoghurts, and other dairy foods rather than full-fat varieties.
- Avoid cream. Use low-fat salad cream, or low-fat yoghurt as a cream substitute.
Don't have too many sugary foods and drinks
Sugary foods and drinks are high in calories, and too much may cause weight gain. It isn't just the amount of sugar that may be bad. Even eating small amounts of sugary foods (sweets, etc) too often is bad for teeth. Tips include:
- Try not to add sugar to tea, coffee, and breakfast cereals. Your taste for sweetness often changes with time. Use artificial sweeteners only if necessary.
- Reduce sugar in any kind of recipe. Use fruit as an alternative to add sweetness to recipes.
- Try sugar-free drinks. Give children water as their main drink.
- If you eat chocolate or sweets, try to keep the quantity down. Eating them as part of a meal, and then brushing your teeth, is better than between meals as snacks.
Don't eat too much salt
Too much salt increases your risk of developing high blood pressure. Guidelines recommend that we should have no more than 6 grams of salt per day. (Most people in the UK currently have more than this.) If you are used to a lot of salt, try gradually to reduce the amount that you have. Your taste for salt will eventually change. Tips on how to reduce salt include:
- Use herbs and spices to flavour food rather than salt.
- Limit the amount of salt used in cooking, and do not add salt to food at the table.
- Choose foods labelled 'no added salt'.
- As much as possible, avoid processed foods, salt-rich sauces, takeaways, and packet soups which are often high in salt.
Don't forget portion sizes
You may be eating very healthy foods but you still need to keep an eye on your portion sizes because if they are too large, you will still gain weight. Deliberately try to take smaller portions when you have a meal. Do not feel that you have to empty your plate. Perhaps change the plates that you have in your cupboard (which may be large) to more medium-sized plates. In this way you will naturally serve up smaller portions. Fill up on fruit and vegetables. Ask for a smaller portion when eating out or ordering a takeaway.
Think about what you are drinking
Many drinks contain calories, including alcoholic and many nonalcoholic drinks . Think about what you are drinking.
- Choose healthier nonalcoholic drinks. Some tips: water contains no calories and can be both refreshing and healthy. Add a slice of lemon or lime to your water. Keep a jug in the fridge so that it stays cool. Also, think about switching your whole-milk latte coffee for a coffee made from skimmed or semi-skimmed milk.
- Keep alcohol within the recommended limits. Drinking above the recommended limits can lead to serious problems. For example, drinking heavily can damage the liver, brain, stomach, pancreas, and heart. It can also cause high blood pressure. Also, alcohol contains a lot of calories, and too much can cause weight gain.
- One unit of alcohol is 10 ml (1 cl) by volume, or 8 g by weight, of pure alcohol. For example, one unit of alcohol is about equal to:
- half a pint of ordinary strength beer, lager, or cider (3-4% alcohol by volume); or
- a small pub measure (25 ml) of spirits (40% alcohol by volume); or
- a standard pub measure (50 ml) of fortified wine such as sherry or port (20% alcohol by volume).
- There are one and a half units of alcohol in:
- a small glass (125 ml) of ordinary strength wine (12% alcohol by volume); or
- a standard pub measure (35 ml) of spirits (40% alcohol by volume).
- Men should drink no more than 21 units of alcohol per week, no more than four units in any one day, and have at least two alcohol-free days a week.
- Women should drink no more than 14 units of alcohol per week, no more than three units in any one day, and have at least two alcohol-free days a week.
- Pregnant women. Advice from the Department of Health states that ... "pregnant women or women trying to conceive should not drink alcohol at all. If they do choose to drink, to minimise the risk to the baby, they should not drink more than 1-2 units of alcohol once or twice a week and should not get drunk".
- One unit of alcohol is 10 ml (1 cl) by volume, or 8 g by weight, of pure alcohol. For example, one unit of alcohol is about equal to:
Eat at least five portions, and ideally 7-9 portions, of a variety of fruit and vegetables per day.
The bulk of most meals should be starch-based foods (such as cereals, wholegrain bread, potatoes, rice, pasta), plus fruit and vegetables.
Limit your intake of fatty food, such as fatty meats, cheeses, full-cream milk, fried food and butter. Use low-fat, monounsaturated or polyunsaturated spreads.
Include 2-3 portions of fish per week, at least one of which should be 'oily' (such as herring, mackerel, sardines, kippers, pilchards, salmon or fresh tuna).
If you eat meat, it is best to eat lean cuts, or poultry such as chicken.
If you do fry, choose a vegetable oil such as sunflower, rapeseed or olive.
Try not to add salt to food and limit foods which are salty.
Now you have read 7 ways to improve your diet, why not look at some of our other slideshows.
Further help and information
Offers a range of tools and articles to support healthy eating and becoming more physically active. The healthy living section of the website gives advice about healthy eating with practical tools and tips: www.nhs.uk/livewell/healthy-eating/Pages/Healthyeating.aspx
Tel: 0300 123 4567 Web: www.nhs.uk/change4life
A government campaign which began in January 2009. Its aims are to prevent people from becoming overweight by encouraging them to eat well, move more and live longer. On joining, receive a personalised pack with tips and advice. Website has details of activities in your local area.
British Nutrition Foundation
The healthy living section of the website gives tips and advice about how to put healthy eating into practice.
Further reading & references
- British Nutrition Foundation
- EatWell, Food Standards Agency
- Mozaffarian D, Micha R, Wallace S; Effects on coronary heart disease of increasing polyunsaturated fat in place of PLoS Med. 2010 Mar 23;7(3):e1000252.
Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. EMIS has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.
Dr Tim Kenny
Dr Michelle Wright
Dr Tim Kenny