Weight gain, weight loss and HIV

Key points

  • Maintaining a healthy weight is important for people with HIV.
  • Gaining too much weight after starting ARVs increases the risk of getting type 2 diabetes and heart disease.
  • Maintaining a healthy BMI, between 18.5 and 25, through eating well and choosing a healthy lifestyle, is recommended.
  • Advice should be sought if weight loss is sudden and unintentional, as being underweight can weaken the immune system.

    As for anyone, it’s important to maintain a healthy body weight when you have HIV. Being overweight or underweight can cause problems for your health.

    Maintaining a healthy weight is about balancing the energy you take in and use up. If you consume more energy (calories) than you use, you’re likely to gain weight. On the other hand, if you burn more calories than you eat, the chances are you’ll lose weight.

    Weighing too little can weaken your immune system and cause bone problems. If you experience an unintended drop in your body weight, especially if it’s accompanied by symptoms such as diarrhoea, vomiting, fevers or pain, you should mention this to your doctor.

    People who gain too much weight in the first year of starting HIV treatment may have an increased risk of developing type 2 diabetes and cardiovascular disease later in life. Getting advice from a dietitian during this first year of treatment is a good idea as they will be able to help you limit weight gain.

    Finding the right balance over time allows you to achieve and maintain a healthy body weight. How and what you eat can help influence both your weight and the levels of fats and sugars in your blood.

    Working out your body mass index (BMI) can provide an approximate idea of how healthy your body weight is for your height. It is calculated using your height and weight measurements. A BMI between 18.5 and 25 is considered to be within the healthy range. As BMI calculations cannot distinguish between muscle and fat, they should only be used as a general guide. A useful tool that helps you to calculate your BMI is available on the NHS Choices website.

    There’s lots of advice and help available on eating well, and on choosing a healthier lifestyle to help you lose weight or maintain a healthy weight. You could start with the information on NHS Choices, or on the British Dietetic Association’s Weight Wise website.

    The HIV organisation The Food Chain provides more information on eating well. Resources such as factsheets and recipes are available on its website. The Food Chain also offers a range of services, including free healthy eating courses and practical cookery classes, for people living with HIV in London. Contact The Food Chain on 020 7843 1800, email info@foodchain.org.uk, or visit its website.

    Being overweight

    The anti-HIV drugs commonly used today are much less likely to cause the body-shape changes (lipodystrophy) that some older drugs did. So if you notice an increase in your weight and accumulations of soft fat around your belly or in other parts of your body, this is likely to be routine fat gain associated with eating too much and not doing enough exercise. Having a large amount of tummy fat in particular makes you more likely to develop type 2 diabetes and heart problems.

    Obesity is when a person is carrying too much weight for their height and it is becoming more common. Someone with a BMI over 30 is considered to be obese. It can cause a number of health problems. As well as type 2 diabetes and heart disease, it can also cause high blood pressure and can increase your risk of developing certain cancers. Being overweight or obese can shorten life expectancy by as much as six or seven years. 


    body mass index (BMI)

    Body mass index, or BMI, is a measure of body size. It combines a person's weight with their height. The BMI gives an idea of whether a person has the correct weight for their height. Below 18.5 is considered underweight; between 18.5 and 25 is normal; between 25 and 30 is overweight; and over 30 is obese. Many BMI calculators can be found on the internet.


    A group of diseases characterized by high levels of blood sugar (glucose). Type 1 diabetes occurs when the body fails to produce insulin, which is a hormone that regulates blood sugar. Type 2 diabetes occurs when the body either does not produce enough insulin or does not use insulin normally (insulin resistance). Common symptoms of diabetes include frequent urination, unusual thirst and extreme hunger. Some antiretroviral drugs may increase the risk of type 2 diabetes.


    An association means that there is a statistical relationship between two variables. For example, when A increases, B increases. An association means that the two variables change together, but it doesn't necessarily mean that A causes B. The relationship isn't necessarily causal.


    Any perceptible, subjective change in the body or its functions that signals the presence of a disease or condition, as reported by the patient.


    immune system

    The body's mechanisms for fighting infections and eradicating dysfunctional cells.

    Obesity is treated by losing weight, which will usually involve healthy, calorie-controlled eating and increasing the amount of exercise you do. This may mean you have to make some quite challenging lifestyle changes, but there is lots of help available. Talk to your healthcare team about the support they can offer, or see the end of this booklet for contacts of other organisations that may be able to help.

    In some cases, where people are severely obese and find they cannot lose weight in other ways, there is the option of surgery. Like any operation, this has some risks attached and may not be suitable for everyone.

    Unintentional weight loss

    The improvements in health that accompany treatment with anti-HIV drugs include improvements in body weight. However, weight loss can be a very serious issue for people with HIV, especially if they have a low CD4 cell count or are ill because of the virus. Unintentionally losing just 3% of your body weight can significantly increase your chances of becoming ill because of HIV.

    An important first step is to identify any medical cause of the weight loss. Loss of weight can be an important warning sign of the presence of an infection or other condition, and is often noticeable before other more specific symptoms become apparent. It is unusual for a person with HIV to lose weight if there is not an underlying medical problem, although lack of appetite, worry and depression can be causes.

    "Loss of weight can be an important warning sign of the presence of an infection or other condition."

    Losing too much weight can be dangerous as it reduces the body’s ability to fight infection and recover. It is important to try and minimise unhealthy weight loss during illness and to put weight back on as lean muscle mass if you lose it during an illness. Changes in your appearance because of weight loss can also be difficult to cope with.

    If you are concerned about your nutritional requirements, cannot face eating during this period or are finding it difficult to keep food down, speak to a member of your healthcare team or a dietitian. They will not bully you into eating food. Rather, they will work with you to try to help you regain your appetite, recommend smaller, more nutritious meals, or look at other solutions.

    Don’t think that eating problems or unintentional weight loss are trivial. They are not, and it is always better to see someone early to prevent problems later.

    Eating when you are ill

    When you become ill you often lose your appetite. However, your energy requirements are often greater when you are sick. What you eat is likely to be very important to how you fight illness and the speed at which you recover.

    • To help prepare for times when you are ill, make sure you always have food available in your home. Canned foods, long-life products and frozen meals can be helpful when you are feeling unwell.
    • If you are unable to afford food then seek help and advice from your local council, HIV treatment centre or an HIV support agency.
    • Snacking through the day, or having small frequent meals, may be easier than eating three main meals; it can also be less tiring to prepare and eat food in this way.
    • It is a good idea to have snacks full of energy at hand for when you are unwell such as nuts, dried fruits and cheese and biscuits.
    • Easy-to-swallow full-fat drinks and yoghurt may also provide a useful source of energy and calories.
    • Your clinic will be able to provide food supplements that contain a balance of the nutrients you need, which may help you boost your energy intake if you are very unwell.
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