How weight loss works
In some respects, it is quite simple. Your weight depends on how much energy you take in (the calories in food and drink) and how much energy your body uses (burns) up:
- If the amount of calories that you eat equals the amount of energy that your body uses up, then your weight remains stable.
- If you eat more calories than you burn up, you put on weight. The extra (or excess) energy is converted into fat and stored in your body.
- If you eat fewer calories than you burn up, you lose weight. Your body has to tap into its fat stores to get the extra energy it needs.
So, to lose weight, you need a calorie deficit. You can achieve this calorie deficit by eating less (taking in fewer calories from food) and also by doing more physical activity (burning up more calories).
It is best not to lose weight too fast. You should aim to lose weight gradually. If you lose more than a kilogram per week, you may lose muscle tissue rather than fat and this isn’t sustainable weight loss. So, it is recommended that you lose an average of 0.5 to 1 kg per week (about 1-2 lb per week).
Top tip: in order to lose weight, your energy in needs to be less than your energy used up. In short, you need to eat less and move more.
Lifestyle change for life
Some people lose weight by strict dieting for a short period. However, as soon as their diet is over, they often go back to their old eating habits, and their weight goes straight back on. Losing weight, and then keeping it off, needs a change in your lifestyle for life. This includes such things as:
- The type of food and drink that you normally buy.
- The type of meals that you eat.
- Your pattern of eating.
- The amount of physical activity that you do.
Top tip: ask family or friends to help and encourage you to keep to a healthy lifestyle. Consider a lifestyle change for the whole family.
Before you start
Motivation is crucial
To lose weight and to keep it off, it is vital that you should be motivated, really want to lose weight, and want to improve aspects of your lifestyle. No weight-loss plan will work unless you have a serious desire to lose weight. You may not feel that being overweight or obese is a problem to you and so you may have little motivation or desire to lose weight. That is fine, so long as you understand the health risks.
Top tip: write down the reasons why you would like to lose weight. Keep referring to this list to motivate yourself.
Set clear goals with a realistic timescale
Based on the recommended rate of weight loss explained above, set yourself a clear weight loss goal with a realistic timescale. Some people aim to get down to a perfect weight. However, this may be a lot of weight to lose for you and you may get fed up about poor progress, and give up. So, you may find it helpful to break up your weight loss goal. For example, you may wish to set yourself a goal to lose 4 kg over the following 4 to 6 weeks. Once you have achieved that goal, you can set yourself another, etc.
For most people, you can start to get health benefits by losing even just 5-10% of your starting weight. For example, if your starting weight was 100 kg, losing 5-10 kg in weight will produce some health benefits for you, even if you are still not at your ideal weight.
Top tip: aim to lose weight steadily, around 0.5-1 kg per week. For most people, health benefits can come from losing the first 5-10% of your weight. This is often about 5-10 kg.
Monitor your current food intake
It is helpful to know how much you normally eat. Try keeping a diary, writing down everything that you eat and drink over a week or so. Include even the smallest of snacks. Are there times of the day that you tend to snack more? Are you eating three meals a day? Are there some snacks that you don’t need? You may find it helpful to discuss your diary with your practice nurse, your doctor or a dietician. The simple fact is that, to lose weight, you must eat less than your current food intake (see above).
Top tip: don’t forget the drinks. Some drinks contain lots of calories, including alcohol and some fizzy drinks.
Eating to lose weight
Aim to eat a healthy balanced diet
Briefly, a healthy diet means:
- Making up the bulk of most meals with starch-based foods (such as cereals, bread, potatoes, rice, pasta). Wholegrain starch-based foods should be eaten when possible.
- Eating plenty of fibre in your diet. Foods rich in fibre include wholegrain bread, brown rice and pasta, oats, peas, lentils, grain, beans, fruit, vegetables and seeds.
- Having at least five portions of a variety of fruit and vegetables per day. These should be in place of foods higher in fat and calories. For example, fruit makes a good, healthy snack if you feel hungry.
- Limiting fatty food such as fatty meats, cheeses, full-cream milk, fried foods, butter, etc. Use low-fat options where possible. Examples are:
- Skimmed or semi-skimmed instead of full-cream milk.
- Using low-fat, monounsaturated or polyunsaturated spreads instead of butter.
- If you eat meat, eating lean meat, or poultry such as chicken.
- Try to grill, bake or steam rather than fry food. If you do fry food, choose a vegetable oil such as sunflower, rapeseed or olive.
- Avoiding sugary drinks and foods such as chocolate, sweets, biscuits, cakes, etc.
- Limiting other foods likely to be high in fat or sugar such as some take-away or fast foods.
- Eating three meals a day and not skipping meals. Always have breakfast. Eat each meal slowly. Skipping meals will just make you feel more hungry, make you think more about food, and make you more likely to overeat in the evening or snack between meals.
- Trying not to add salt to food, and avoiding foods that are salty.
- Including 2-3 portions of fish per week. At least two of which should be ‘oily’ (such as herring, mackerel, sardines, kippers, pilchards, salmon, or fresh tuna).
See separate leaflet in this series, called ‘Healthy Eating’, which gives more details. Also, many books on food and health give details. Your practice nurse or dietician may also be able to help.
Top tip: low-fat foods are generally best. But remember, some low-fat foods and drinks such as alcohol, sugary drinks, and sweets, are still high in calories.
Plan what you eat
It is important to plan ahead. Perhaps you could plan each day’s meals and recipes the day before, or plan a week’s meals at a time. In this way you will know exactly how much food you will be eating. This is better than looking in the cupboard and fridge before mealtimes or snacks to see what is there.
It is best to separate eating from other activities, as this helps you to keep to your planned eating for the day. So, try not to eat whilst on the move, whilst watching TV, during meetings, etc.
Top tip: plan tomorrow’s eating today.
Change your eating habits
Do you have any eating habits that can improve?
- Are you eating larger and larger portions when you have a meal? 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 in your cupboard (which may be large) to more medium-sized plates. In this way you will naturally serve up smaller portions.
- What do you have for snacks? Try changing chocolates, cakes or crisps for fruit. The Change4Life website listed below gives tips about healthy snack alternatives.
- Do you have second helpings at meal times when you are really already full?
- Skipping meals is usually a bad idea. It sounds a good idea, but many people just become hungry, have snacks later in the day, and eat too much at the next meal. Eating at regular mealtimes may be a first important change. Three healthy meals a day is best.
- Do you always have a pudding? Will a light yoghurt do instead of a sweet pastry?
- Do you eat quickly? Are you ready for a second helping before most people have half finished their first plateful? Overweight people, on average, eat faster than slimmer people. It is best to train yourself to chew each mouthful for longer, and to eat slowly.
Top tips: eating three healthy meals each day, including breakfast, is better than skipping meals. Eat slowly, chew longer. Put your knife and fork down between each mouthful.
Change the food you buy
One step towards improving eating habits is to change the contents of your shopping basket. For example, if you never buy biscuits, they will not be in the cupboard to tempt you. Most food labels say what is in the food, so this can help you to buy healthier food. It may be helpful to plan a shopping list, and stick to it. However, whilst you are learning which are the healthier foods, it may also be helpful to spend some time comparing food labels before deciding on what to buy.
Top tips: do not shop for food when you are hungry; after a meal is best. Remove temptations by changing the contents of your cupboards.
Try new recipes
Most people have a standard set of recipes and meals that they repeat. These may be old favourites, but you may need to adapt these and also find new, healthier recipes.
Top tip: when you are on a weight-reducing diet, try to learn a new healthy recipe each week. When you have reached your goal weight, you should then have plenty of new healthy meal ideas to help keep your weight down.
Consider eating more soup
There is some evidence that eating soup may fill you up for longer. Also, if you have soup as a starter to your meal, you are less likely to overeat for the rest of your meal. If you take, for example, chicken and vegetables and have this with a drink of water, you will feel full for a certain period of time afterwards. However, if you take the same food but blend it with the water to make a soup, eating the soup can keep your hunger satisfied for a longer period. This is thought to be due to the fact that your stomach empties more slowly if you eat soup than if you eat chicken and vegetables and drink water separately. As a result, your stomach wall is stretched for a longer period and messages are sent to your brain switching off the feeling of hunger for a greater period of time.
Top tip: make sure that it is a low-fat soup that you are eating. Avoid creamy or high-calorie soups.
Are you feeling physically hungry?
Your appetite is a very powerful thing. This is why many people find it so difficult to lose weight. It is true that some people feel hungry more often than others. However, feeling hungry does not always mean that your body physically needs food. Sometimes you can feel emotional hunger. For example, feeling hungry because you are tired, bored, fed up, upset, etc.
Think about this and try to resist eating as soon as you feel hungry. Are you feeling physically hungry or are you just looking for food to fulfil an emotional hunger? If you do have a strong appetite, try to fill up at meal times with vegetables and fruit which have a lot of fibre and bulk, but are low in calories.
Top tips: drink lots or water and eat lots of fruit and vegetables to help counter physical hunger. Think about whether your hunger is for emotional reasons.
A note about special diets
Many special ‘wonder’ diets are advertised, but they are often not helpful. This is because your old eating habits will usually return after a short special diet, and weight often goes back on.
Top tip: it is not usually a special diet that you need, but a lifelong change to a healthier diet as part of a healthier lifestyle.
Be careful about what you drink
Many people use drinks full of calories to quench their thirst. Sugary drinks, such as cola, tea and coffee with milk and sugar, milk, and alcoholic drinks, all contain calories. Alcoholic drinks also contain a lot of calories. One of the easiest ways to cut back on calories is simply to drink water as your main drink.
Top tips: keep some water in a plastic bottle in the fridge. Chilled water is surprisingly refreshing. The Change4Life website listed below also gives tips and advice about drink swaps to cut down on the calories.
An interesting research trial involving water
A study published in 2010 concluded that drinking water just before meals may also help people to lose weight. In the study, 48 overweight adults aged 55 to 75 were put into two groups. The first group was asked to eat a low-calorie diet but not to drink any extra water before meals. The second group was asked to eat the same diet but also to drink two glasses of water (500 ml) just before each meal. After 12 weeks the water drinking group had lost, on average, about 2 kg more than the non-water drinking group. The theory was that the water drinking group felt fuller during the meal and so ate less food at each meal.
This is just one small study and so it is difficult to base firm advice on it. However, it sounds logical and may be worth a try. Note: drinking excessive amounts of water is not helpful and, in rare cases, can be dangerous. There have been a few case reports of people dying from drinking excessive amounts of water. However, the extra 500 ml of water per meal in this study is reasonable.
Increase your physical activity levels
It is recommended that all adults should aim for at least 30 minutes of moderate-intensity physical activity on at least five days of the week. However, if you are overweight or obese and are aiming to lose weight, if possible you should try to do around 60-90 minutes on at least five days of the week.
Moderate physical activity includes: brisk walking, jogging, dancing, swimming, badminton, tennis, etc. In addition, try to do more in your daily routines. For example, use stairs instead of lifts, walk or cycle to work or school, etc. Avoid sitting for too long in front of the television or a computer screen. Take regular breaks whilst working. The good news is that you don’t have to do this physical activity all in one chunk. You can break it up into blocks of 10-15 minutes. See separate leaflet called ‘Physical Activity for Health’, which gives more details.
Top tip: build your exercise levels up gradually. If you are not used to physical activity, try starting with a 30-minute brisk walk every day and then building up from there.
Monitor your behaviour and progress
Just as keeping a food diary can be helpful at the beginning if you are trying to lose weight, it can also be useful as a way to monitor your eating during your weight loss. Studies have shown that keeping a food diary can help people lose weight just through the process of writing things down. You can use the same diary to keep a track of your physical activity levels as well.
It is also important to weigh yourself regularly to monitor your progress. Once weekly is recommended. The first kilogram is the easiest to lose. This is because you lose water from your body at first as well as fat. Be aware that the first kilogram or so may seem to fall off, but then the weight loss slows down. This is normal. Also, don’t be disheartened by minor weight increases or levelling off in weight for a few days. Look for the overall trend in your weight loss over several months.
Top tip: regular weighing and encouragement by a practice nurse or dietician may be helpful.
Get help and support
Some people may feel motivated enough and have all of the information that they need in order to lose weight without any help from others. However, you don’t have to try to lose weight alone. There is a wealth of help available. Ask your doctor or practice nurse for advice. A referral to a dietician may be helpful. One-on-one counselling or group counselling may be available in your area on the NHS. There may also be some local groups to help you increase your physical activity levels.
A number of commercial weight loss groups meet regularly in the UK. In fact, there is some research evidence to suggest that people who join a weight loss group are more likely to be successful in losing weight than those who don’t. There are also internet-based programmes and self-help books that can help you with your weight loss.
Drug treatment to help with weight loss
Medication to help with weight loss may be an option for some people who want to lose weight. However, there are no wonder drugs available, and lifestyle changes to improve your diet and increase your physical activity levels are still important.
The drug orlistat is available on prescription from your doctor and low-dose orlistat is also available to buy over-the-counter in pharmacies. Doctors and pharmacists are given specific guidelines on when orlistat should be used. It cannot be used in everyone who wants to lose weight and is only recommended in people over a certain body mass index (BMI). For a doctor to prescribe orlistat, they also need to be sure that you have tried changing your diet and increasing your physical activity levels first.
Orlistat works by blocking chemicals (enzymes) in your gut which digest fat. Nearly a third of the fat that you eat is blocked by orlistat. The undigested fat is not absorbed into your body, and is passed out with your faeces (stools). It is important to follow a low-calorie, low-fat diet and maintain regular physical activity if you are taking orlistat. You will also need regular follow-up with your doctor or pharmacist. See separate leaflet called ‘Orlistat – Help With Weight Loss’, which gives further details about this drug and when it may be used.
Note: two other drugs, sibutramine and rimonabant previously used to help with weight loss are no longer available in the UK because of concerns over their safety.
Surgery to help with weight loss
This may be an option if you are very obese. However, surgery is usually only offered if other ways to lose weight have not worked (including diet, increasing your physical activity levels and orlistat). Weight loss surgery usually gives very good results and most people do lose a lot of weight. But this is specialist surgery and it is a major operation. In some people, surgery may not be advised because health issues may mean that having an anaesthetic could be dangerous.
Surgery to aid weight loss is called bariatric surgery. There are different types of bariatric surgery available. In one type, the surgery reduces the size of your stomach so that you are not able to eat as much. You feel full more quickly. Another type of bariatric surgery makes the food that you eat bypass some of your intestine. This means that you are not able to absorb as many calories from food as you would normally. There are also newer techniques that have been developed to help weight loss, including intragastric balloons (small balloons that sit inside your stomach).
After surgery, you will need to make long-term changes to your eating habits. You will be given help and guidance with this. You will also need long-term medical follow-up.
For further information about surgery to help with weight loss, please see separate leaflet called ‘Surgery for Obesity’.
Tempting situations and special occasions
It is natural that you will be tempted by different situations to put you off track with your eating and weight loss. It is important to recognise that holidays, festivals, eating out, etc, may affect your everyday food choices and what you had planned to eat.
Can you identify any tempting situations? Some people find that watching food programmes on TV makes them feel hungry. How about smells from the kitchen from someone cooking who is not aware that you are trying to lose weight? Do you get pressure from family or friends to eat or drink more? Can you avoid tempting situations? If not, think about ways of coping with them.
Top tip: go and clean your teeth or take a short brisk walk when you are tempted to eat between meals.
Stress, depression and your weight
Many people eat as a comfort, or as a way of coping with stress. How do you cope with stress? Is stress, unhappiness, depression, etc, a reason for you to overeat or to binge eat? If so, can you plan alternative strategies? For example, relaxation tapes, going for a walk, talking to a friend, etc.
Top tip: see a doctor if you feel that depression is a problem. Depression can often be treated.
Keeping the weight off
Many people lose weight but at the end of their ‘diet’, the weight goes back on. The main reason this happens is because their weight-reducing diet was only a temporary change to their unhealthy diet and lifestyle. To keep your weight off, it is important that you make permanent changes. This usually means:
- Keeping to a healthy diet.
- Exercising regularly.
- A change for the whole household. It is difficult for one member of a household to shop and eat differently to the rest. It is best that the whole household should eat a healthy diet.
It does not mean less enjoyment of food. However, it may take a while to learn to enjoy different foods, meals, and recipes. Some people need more support to keep to their new weight than when they were actually dieting and losing weight. A local support group may be able to help.
Top tip: after losing some weight, weigh yourself once a week to keep a check on your weight. This way you will see if your weight starts to increase again and you can do something about it early on.
Further help and information
A range of tools and articles to support healthy eating and becoming more physically active.
Tel: 0300 123 4567 Web: www.nhs.uk/change4life
A government campaign that began in January 2009 that aims 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. For the specific information about snack and drink ‘swaps’, see here: www.nhs.uk/change4life/Pages/change-for-life-adults.aspx
British Dietetic Association – Weight Wise
This is an independent site, with unbiased, easy-to-follow hints and tips, based on the latest evidence, to help you manage your weight for good. It will help you take a look at your current eating habits and physical activity levels, and offer a practical approach to setting your own goals for lifestyle change.
British Nutrition Foundation
Healthy living section of their website provides advice about how to put healthy eating and active lifestyle into practice, for life. It includes a good information sheet about eating foods with a lower-energy density to help you lose weight.
National Obesity Forum
First Floor, 6a Gordon Road, Nottingham NG2 5LN
Tel: 0115 846 2109 Web: www.nationalobesityforum.org.uk
Website has a section for families and individuals that offers advice and support about how to adopt a healthier lifestyle.
1-19 Torrington Place, London WC1E 6BT
Tel: 020 7679 1853 (not a helpline) Web: www.weightconcern.org.uk
Weight Concern is a registered charity, set up to tackle the rising problem of obesity. Weight Concern has shown how psychologists, dieticians and exercise specialists working together can help people make the lifestyle changes they want, to control their weight.
British Obesity Surgery Patient Association
PO Box 805, Taunton, Somerset TA1 9DH
Tel: 08456 02 04 46 Web: www.bospa.org
Provides support and information to people in the UK considering obesity surgery.
References and Disclaimer | Provide feedback
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