Obesity

Obesity causes & treatments - Illnesses & conditions | NHS inform Home Illnesses and conditions Symptoms and self-help Tests and treatments Healthy living Care, support and rights Scotlands Service Directory 0 Home Illnesses and conditions Nutritional Obesity Obesity About obesity Causes of obesity Diagnosing obesity Treating obesity About obesity The term obese describes a person whos very overweight, with a lot of body fat. Its a common problem in the UK thats estimated to affectaround one in every four adults and around one in every five children aged 10 to 11. Defining obesity There are many ways in which a persons health in relation to their weight can be classified, but the most widely used method is body mass index (BMI). BMI is a measure of whether youre a healthy weight for your height. You can use the BMI healthy weight chart to work out yourscore. For most adults, a BMI of: 18.5 to 24.9 means youre a healthy weight 25 to 29.9 means youre overweight 30 to 39.9 means youre obese 40 or above means youre severely obese BMI isnt used to definitively diagnose obesity, because people who are very muscular sometimes have a high BMI without excess fat.But for most people, BMI is a useful indication of whether theyre a healthy weight, overweight or obese. A better measure of excess fat is waist circumference, which can be used as an additional measure in people who are overweight (with a BMI of 25 to 29.9) or moderately obese (with a BMI of 30 to 34.9). Generally, men with a waist circumference of 94cm (37in) or more and women with a waist circumference of 80cm (about 31.5in) or more are more likely to develop obesity-related health problems. Read more about diagnosing obesity Risks of obesity Its very important to take steps to tackle obesity because, as well as causingobvious physical changes, itcan lead to a number of serious and potentially life-threatening conditions, such as: type 2 diabetes coronary heart disease some types of cancer, such as breast cancer and bowel cancer stroke Obesity can also affect your quality of life and lead to psychological problems, such as depression andlow self-esteem (see below for more information about the health problems associated with obesity). Causes of obesity Obesity is generally caused by consuming more calories  particularly those in fatty and sugary foods  than you burn off through physical activity.The excess energy is stored by the body as fat. Obesity is an increasingly common problem because for many people modern living involves eating excessive amounts of cheap, high-calorie food and spending a lot of time sitting down, at desks, on sofas or in cars. There are also some underlying health conditions that can occasionally contribute to weight gain, such as an underactive thyroid gland (hypothyroidism) , although these type of conditions dont usually cause weight problems if theyre effectively controlled with medication. Read more about the causes of obesity Treating obesity The best way to treat obesity is to eat a healthy, reduced-calorie diet and exercise regularly . To do this you should: eat a balanced, calorie-controlled diet as recommended by your GP or weight loss management health professional (such as a dietitian) join a local weight loss group take up activities such as fast walking , jogging, swimming or tennis for 150 to 300minutes (two-and-a-half to five hours) a week eat slowly and avoid situations where you know you could be tempted to overeat You may also benefit from receiving psychological support from a trained healthcare professional to help change the way you think about food and eating. If lifestyle changes alone dont help you lose weight, a medication called orlistat may be recommended. If taken correctly, this medication works by reducing the amount of fat you absorb during digestion. Your GP will know whether orlistat is suitable for you. In rare cases, weight loss surgerymay be recommended. Read more about how obesity is treated Other obesity-related problems Obesity cancause anumber of further problems, including difficulties with daily activities and serious health conditions. Day-to-day problems related to obesity include: breathlessness increased sweating snoring difficultydoingphysical activity often feeling very tired joint andback pain low confidence and self-esteem feeling isolated The psychological problems associated with being obese can also affect your relationships with family and friends, and may lead to depression. Serious health conditions Being obese can also increase your risk of developing many potentially serioushealth conditions, including: type 2 diabetesa condition that causes a persons blood sugar level to become too high high blood pressure high cholesterol andatherosclerosis (where fatty deposits narrow your arteries), which can lead to coronary heart disease andstroke asthma metabolic syndrome a combination of diabetes, high blood pressure and obesity several types of cancer , including bowel cancer, breast cancerand womb cancer gastro-oesophageal reflux disease (GORD) where stomach acid leaks out of the stomach and into the oesophagus (gullet) gallstones small stones, usually made of cholesterol, that form in the gallbladder reduced fertility osteoarthritis a condition involving pain and stiffness in your joints sleep apnoea a condition that causes interrupted breathing during sleep, which can lead to daytime sleepiness with an increased risk of road traffic accidents, as well as a greater risk of diabetes, high blood pressure and heart disease liver disease and kidney disease pregnancy complications,such as gestational diabetes orpre-eclampsia (when a woman experiences a potentially dangerous rise in blood pressure during pregnancy) Obesity reduces life expectancy by an average of3 to10 years, depending on how severe it is. Its estimated that obesity and being overweight contribute to at least1 in every 13 deaths in Europe. Outlook Theres no quick fix for obesity. Weight loss programmes take time and commitment, and work best when fully completed. The healthcare professionals involved with your care should provide encouragement and advice about how to maintain the weight loss achieved. Regularly monitoring your weight, setting realistic goals and involving your friends and family with your attempts to lose weightcan also help. Remember that even losing what seems like a small amount of weight, such as 3% or more of your original body weight, and maintaining this for life, can significantly reduce your risk of developing obesity-related complications like diabetes and heart disease. Causes of obesity Obesity is generally caused by eating too much and moving too little. If you consume high amounts of energy, particularly fat and sugars, but dont burn off the energy through exercise and physical activity, much of the surplus energy will be stored by the body as fat. Calories The energy value of food is measured in units called calories. The average physically active man needs about 2,500 calories a day to maintain a healthy weight, and the average physically active woman needs about 2,000 calories a day. This amount of calories may sound high, but it can be easy to reach if you eat certain types of food. For example, eating a large takeaway hamburger, fries and a milkshake can total 1,500 calories  and thats just one meal. Another problem is that many people arent physically active, so lots of the calories they consume end up being stored in their body as fat. Poor diet Obesity doesnt happen overnight. It develops gradually over time, as a result of poor diet and lifestyle choices, such as: eating large amounts of processed or fast food  thats high in fat and sugar drinking too much alcohol alcohol contains a lot of calories, and people who drink heavily are often overweight eating out a lot you may be tempted to also have a starter or dessert in a restaurant, and the food can be higher in fat and sugar eating larger portions than you need you may be encouraged to eat too much if your friends or relatives are also eating large portions drinking too many sugary drinks  including soft drinks and fruit juice comfort eating if you have low self-esteem or feel depressed, you may eat to make yourself feel better Unhealthy eating habits tend to run in families. You may learn bad eating habits from your parents when youre young and continue them into adulthood. Read more about eating well Lack of physical activity Lack of physical activity is another important factor related to obesity. Many people have jobs that involve sitting at a desk for most of the day. They also rely on their cars, rather than walking or cycling . Forrelaxation, many people tend to watch TV, browse the internet or play computer games, and rarely take regular exercise . If youre not active enough, you dont use the energy provided by the food you eat, and the extra energy you consume is stored by the body as fat. The Department of Health recommends that adults do at least 150 minutes (two-and-a-half hours) of moderate-intensity aerobic activity, such as cycling or fast walking, every week. This doesnt need to be done allin one go, but can be broken down into smaller periods. For example, you could exercise for 30 minutes a day for five days a week. If youre obese and trying to lose weight , you may need to do more exercise than this. It may help to start off slowly and gradually increase the amount of exercise you do each week. Read more about the physical activity guidelines for adults Genetics Some people claimtheres no point trying to lose weight because it runs in my family or its in my genes. While there are some rare genetic conditions that can cause obesity, such asPrader-Willi syndrome, theres no reason why most people cant lose weight. It may be true that certain genetic traits inherited from your parentssuch as having a large appetitemay make losing weight more difficult, but it certainly doesnt make it impossible. In many cases, obesity is more to do with environmental factors, such as poor eating habits learned during childhood. Medical reasons In some cases, underlying medical conditions may contribute to weight gain. These include: an underactive thyroid gland (hypothyroidism) where your thyroid gland doesnt produce enough hormones Cushings syndromea rare disorder that causes the over-production of steroid hormones However, if conditions such as these are properly diagnosed and treated, they should pose less of a barrier to weight loss. Certain medicines, including some corticosteroids , medications for epilepsy and diabetes , and some medications used to treat mental illness including antidepressants and medicines for schizophrenia can contribute to weight gain. Weight gain can sometimes be a side effect of stopping smoking Diagnosing obesity Body mass index (BMI) is widely used as a simple and reliable way of finding out whether a person is a healthy weight for their height. For most adults, having a BMI of 18.5 to 24.9 means youre considered to be a healthy weight. A person with a BMI of 25 to 29.9 is considered to be overweight, and someone with a BMI over 30 is considered to be obese. While BMI is a useful measurement for most people, its not accurate for everyone. For example, the normal BMI scores may not be accurate if youre very muscular because muscle can add extra pounds, resulting ina high BMI when youre not an unhealthy weight. In such cases, your waist circumference may be a better guide (see below). Whats considered a healthy BMI is also influenced by your ethnic background. The scores mentioned above generally apply to people with a white Caucasian background. If you have an ethnic minority background, the threshold for being considered overweight or obese may be lower. BMI shouldnt be used to work out whether a child is a healthy weight, becausetheir bodies are still developing.Speak to your GP if you want to find out whether your child is overweight. Visiting your GP If youre overweight or obese,visit your GP for advice about losing weight safely and to find out whether you have an increased risk of health problems. Your GPmay ask about: your lifestyle  particularly your diet and how much physical activity you do; theyll also ask you whether you smoke and how muchalcohol you drink any possible underlying causes for your obesity  for example, if youre taking medication or have a medical condition that may contribute toweight gain how you feel about being overweight  for example, if it makes you feel depressed how motivated you are to lose weight your family history  as obesity and other health conditions, such as diabetes , are often more common in families As well as calculating your BMI, your GP may also carry out tests to determine whether youre at increased risk of developing health complications because of your weight. These could includemeasuring your: blood pressure glucose (sugar) and cholesterol levels in a blood sample waist circumference (the distance around your waist) People with very large waists  generally, 94cm (37in) or more in men and 80cm (about 31.5in) or more in women  are more likely to develop obesity-related health problems. Your GP may also take your ethnicity into account because it can affect your risk of developing certain conditions. For example, some people of Asian, African or Afro-Caribbean ethnicity may be at increased risk of high blood pressure (hypertension) . Healthy waist measurements can also be different for people from different ethnic backgrounds. After your assessment, youll be offered an appointment to discuss the results in more detail, ask any questions that you have, and fully explore the treatment options available to you. Treating obesity If youre obese, speak to your GP for advice about losing weight safely. Your GP can advise you about losing weight safely by eating a healthy, balanced diet and regular physical activity . They can also let you know aboutother useful services, such as: local weight loss groups  these could be provided by your local authority, the NHS, or commercial services you may have to pay for exercise on prescription  where youre referred to a local active health team for a number of sessions under the supervision of a qualified trainer If you have underlying problems associated with obesity, such as polycystic ovary syndrome (PCOS), high blood pressure , diabetes or obstructive sleep apnoea , your GP may recommend further tests or specific treatment. In some cases, they may refer you to a specialist. Read more about how your GP can help you lose weight Diet Theres no single rule that applies to everyone, but to lose weight at a safe and sustainable rate of 0.5 to 1kg (1lb to 2lbs) a week, most people are advised to reduce their energy intake by 600 calories a day. For most men, this will mean consuming no more than 1,900 calories a day, and for most women, no more than 1,400 calories a day. The best way to achieve thisis to swap unhealthy and high-energy food choices  such as fast food, processed food and sugary drinks (including alcohol)  for healthier choices. A healthy diet should consist of: plenty of fruit and vegetables plenty of potatoes, bread, rice, pasta and other starchy foods (ideally you should choose wholegrain varieties) somemilk and dairy foods some meat, fish, aggs,beansand other non-dairy sources of protein just small amounts of food and drinks that are high infatandsuagr Try to avoidfoods containing high levels of salt because they can raise your blood pressure, which can be dangerousfor people who are already obese. Youll also need to checkcalorie information for each type of food and drink you consume to make sure you dont go over your daily limit. Some restaurants,cafs and fast food outlets provide calorie information per portion, although providing this information isnt compulsory. Be carefulwhen eating out because some foods can quickly take you over the limit, such as burgers, fried chicken, and some curries or Chinese dishes. Diet programmes andfad diets Avoidfad diets that recommend unsafe practices, such as fasting (going without food for long periods of time) or cutting out entire food groups. These types of dietsdont work, can make you feel ill, and arent sustainable because they dont teach you long-term healthy eating habits. This isnt to say that all commercial diet programmes are unsafe. Many are based on sound medical and scientific principles and can work well for some people. A responsible diet programme should: educate you about issues such as portion size, making behavioural changesand healthy eating not be overly restrictive in terms of the type of foods you can eat be based on achieving gradual, sustainable weight loss rather than short-term rapid weight loss, which is unlikely to last Very low calorie diets Avery low calorie diet (VLCD) is where you consume less than 800 calories a day. These diets can lead to rapid weight loss, butthey arent a suitable or safe method for everyone, and they arent routinely recommended for managing obesity. VLCDs are usually only recommended if you have an obesity-related complication that would benefit from rapid weight loss. VLCDsshouldnt usually be followed for longer than 12 weeks at a time, and they should only be used under the supervision of a suitably qualified healthcare professional. Speak to your GP first ifyoure considering this type of diet. Exercise Reducing the amount of calories in your diet will help you lose weight, but maintaining a healthy weight requires physical activity to burn energy. As well as helping you maintain a healthy weight, physical activity also has wider health benefits. For example, it can help prevent and manage more than20 conditions, such as reducing the risk oftype 2 diabetes by 40%. The Chief Medical Officers recommend that adults should do at least 150 minutes (two-and-a-half hours) of at least moderate-intensity activity a week  for example, five 30-minute bouts a week. Something is better than nothing, and doing just 10 minutes of exercise at a time is beneficial. Moderate-intensity activity is any activity that increases your heart and breathing rate, such as: brisk walking cycling recreational swimming dancing Alternatively, you could do 75 minutes (one hour, fifteen minutes) of vigorous-intensity activitya week, or a combination of moderate and vigorous activity. During vigorous activity, breathing is very hard, your heart beats rapidly and you may be unable to hold a conversation. Examples include: running most competitive sports circuit training You should also do strength and balance training two days a week. This could be in the form of agym workout, carrying shopping bags, or doing an activity such as tai chi .Its also critical that you break up sitting (sedentary) time by getting up and moving around. Read more about strengthandbalance exercises . Your GP, weight loss adviser or staff atyour local sports centre can help you create a plan suited to your own personal needs and circumstances, with achievable and motivating goals. Start small and build up gradually. Its alsoimportant to find activities you enjoy and want to keep doing. Activities with a social element or exercising with friends or family can help keep you motivated. Make a start today  its never too late. Read more about the physical activity guidelines for adults and the physical activity guidelines for older adults . Other useful strategies Evidence has shown that weight loss can be more successful if it involves other strategies, alongside diet and lifestyle changes. This could include things like: setting realistic weight loss goals  if youre obese, losing just 3% of your original body weight can significantly reduce your risk of developing obesity-related complications eating more slowly and being mindful of what and when youre eating  for example, not being distracted by watching TV avoiding situations where you know you may be tempted to overeat involving your family and friends with your weight loss efforts they can help to motivate you monitoring your progress  for example, weigh yourself regularly and make a note of your weight in a diary Getting psychological support from a trained healthcare professional may alsohelp you change the way you think about food and eating. Techniques such as cognitive behavioural therapy (CBT)can be useful. Avoiding weight regain Its important to remember that as you lose weight your body needs less food (calories), so after a few months, weight loss slows and levels off, even if you continue to follow a diet. If you go back to your previous calorie intake once youve lost weight, its very likely youll put the weight back on. Increasing physical activity to up to 60 minutes a day and continuing to watch what you eat may help you keep the weight off. Medication Manydifferent types of anti-obesity medicines have been tested in clinical trials, but only one has proved to be safe and effective: orlistat. You can only use orlistat if a doctor or pharmacist thinks its the right medicine for you. In most cases, orlistat is only available on prescription. Only one product (Alli) is available over the counter directly from pharmacies, under the supervision of a pharmacist. Orlistat works by preventingaround a third of the fat from the food you eat being absorbed. The undigested fat isnt absorbed into your body and is passed out with your faeces (stools). This will help you avoid gaining weight, but wont necessarily cause you to lose weight. A balanced diet and exercise programme should be started before beginning treatment with orlistat, and you should continue this programme during treatment and after you stoptaking orlistat. When orlistat should be used Orlistat will usually only be recommended if youve made a significant effort to lose weight through diet, exercise or changing your lifestyle. Even then, orlistat is only prescribed if you have a: body mass index (BMI) of 28 or more, and other weight-related conditions,such as high blood pressure or type 2 diabetes BMI of 30 or more Before prescribing orlistat, your doctor will discuss the benefits and potential limitations with you, including any potential side effects (see below). Treatment with orlistat must be combined with a balanced low-fat diet and other weight loss strategies, such as doing more exercise.Its important that the diet is nutritionally balanced over three main meals. If youre prescribed orlistat, youll also be offered advice and support about diet, exercise and making lifestyle changes. Orlistat isnt usually recommended for pregnant or breastfeeding women. Dosage and duration of treatment One orlistat capsule is taken with water immediately before, during or up to one hour after, each main meal (up to a maximum of three capsules a day). If you miss a meal, or the meal doesnt contain any fat, you shouldnt need to take the orlistat capsule. Your doctor should explain this to you, or you can check the patient information leaflet that comes with your medicine. Treatment with orlistat should only continue beyond three months if youve lost 5% of your body weight. It usually starts to affect how you digest fat withinone to twodays. If you havent lost weight after taking orlistat forthree months, its unlikely to be an effective treatment for you. Consult your doctor or pharmacist, as it may be necessary to stop your treatment. Taking orlistat with other health conditions See your GP before starting treatment with orlistat if you have another serious health condition, such as type 2 diabetes, high blood pressure, or kidney disease, which youre taking medication for. It may be necessary to change the dose of your medicine. If you havetype 2 diabetes, it may take you longer to lose weight using orlistat, so your target weight loss after three months may therefore be slightly lower. If orlistat has helped you lose weight after three months, your prescription may be continued for up to a year. After that, your GP will carry out a review and decide whether you should continue taking it. Side effects Common side effects of orlistat include: fatty or oily stools needing the toilet urgently passing stools more frequently an oily discharge from your rectum (you may have oily spots on your underwear) flatulence (wind) stomach pain headaches upper respiratory tract infections, such as a cold These side effects are much less likely to occur if you stick to a low-fat diet. Women takingthe oral contraceptive pill should use an additional method of contraception , such as a condom , if they experience severe diarrhoea while taking orlistat. This is because the contraceptive pill may not be absorbed by your body if you have diarrhoea, so it may not be effective. Surgery Weight loss surgery, also called bariatric surgery, is sometimes used to treat people who are severely obese. Bariatric surgery is usually only available on the NHS to treat people with severe obesity who fulfil all of the following criteria: they have a BMI of 40 or more, or between 35 and 40 and another serious health condition that could be improved with weight loss, such as type 2 diabetesorhigh blood pressure all appropriate non-surgical measures have been tried, but the person hasnt achieved or maintained adequate, clinically beneficial weight loss the person is fit enough to have anaesthesia and surgery the person has been receiving, or will receive, intensive management as part of their treatment the person commits to the need for long-term follow-up Bariatric surgery may also be considered as a possible treatment option for people with a BMI of 30 to 35 who have recently (in the last 10 years) been diagnosed with type 2 diabetes. In rare cases, surgery may be recommended as the first treatment (instead of lifestyle treatments and medication) if a persons BMI is 50 or above. Treating obesity in children Treating obesity in children usually involves improvements to diet and increasing physical activity using behaviour change strategies. The amount of calories your child should eat each day will depend on their age and height. Your GP should be able to advise you about a recommended daily limit, and they may also be able to refer you to your local family healthy lifestyle programme. Children over the age of five should ideally get at least one hour (60 minutes) of vigorous-intensity exercise a day, such as running or playing football or netball. Sedentary activities, such as watching television and playing computer games, should be restricted. Read more about the physical activity guidelines for children and young people Referral to a specialist in treating childhood obesity may be recommended if your child develops an obesity-related complication, or theres thought to be an underlying medical condition causing obesity. The use of orlistat in children is only recommended in exceptional circumstances, such as if a child is severely obese and has an obesity-related complication. Bariatric surgery isnt generally recommended for children, but may be considered for young people in exceptional circumstances, and if theyve achieved, or nearly achieved, physiological maturity. Source: NHS 24 - Opens in new browser window Last updated: 21 November 2023 How can we improve this page? Help us improve NHS inform Thank You Your feedback has been received Dont include personal information e.g. name, location or any personal health conditions. 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