Sustainable approaches to weight

How do you combine diet and exercise for lasting weight loss?

Use activity as a partner to your eating changes, not a way to eat as you like. Diet combined with activity tends to give more benefit than diet alone, and it helps you keep more muscle¹. Exercise on its own, with eating unrestricted, was not effective for weight loss, because people tended to eat more to make up for it⁵. Adding exercise to an eating plan may do little extra for early weight loss, but it may matter more for keeping weight off⁶.

For the activity side, European guidelines recommend at least 150 minutes a week of moderate aerobic exercise, such as brisk walking, plus resistance (strengthening) exercise to build muscle⁷. Aerobic activity is best for reducing fat, and a programme that includes strengthening is needed to build muscle⁷.

You don't have to start there. Begin with the amount you can manage now and build up gradually; the weekly totals are targets to work towards over time. Brisk walking is a good place to begin, and strengthening can be added later.

What helps you keep a healthy weight long term?

Keeping weight off rests mostly on gradual, permanent changes to what you eat, what you drink and how active you are, rather than short-term dieting². Activity matters here. Guidance on how much varies: more than 150 minutes, preferably 300 minutes, a week of at least moderate aerobic activity to prevent regain⁴; more than 250 minutes a week of moderate activity¹; or 150 to 300 minutes or more³. Treat these as a direction and build towards them over time. Maintaining or increasing activity after weight comes off is likely the most promising way to resist regain⁵.

A few habits help:

• Set a specific goal and keep track of it. For adults aged 40 and over with overweight or obesity, this helped people both start and keep up change⁸. Tracking works best when you do it regularly, such as weekly⁹.
• Check your weight about once a week³.
• Look for support that respects your choices. A person-centred style of help was linked with keeping up activity and healthy eating for a year or more⁸.
• Use a tool that suits you. A step counter, an activity app or a notebook can all work.
• Be realistic and kind to yourself. Regaining weight is common¹⁰, and habits take time to change.

How do you set realistic weight goals?

A realistic first goal is modest: guidelines suggest losing 5–10% of your starting weight over about 6 months³, and even that much can bring clear health benefits⁷. Aim for a steady pace rather than losing weight suddenly with diets¹¹, and give your goal months rather than weeks. Staying at your current weight has benefits too².

Goals can go beyond the scale. European guidelines say weight goals should be realistic, individualised and aimed at the long term, and that waist measurement and body composition deserve attention too⁷. An activity goal counts as well: the NHS suggests getting active for 150 minutes a week¹¹.

Set specific goals for the near future, such as this week, and check your progress regularly¹². If you want help finding a pace that suits you, a doctor or other health professional can help.

What does energy balance mean for weight?

Energy balance means the calories your body uses compared with the calories you eat and drink. To stay at about the same weight, the two should match; if you take in more than you use, the extra is stored as fat¹³. To lose weight, you need to use more than you take in¹. The NHS says you can do this by eating and drinking fewer calories and being more active¹⁴.

Needs vary with your age, weight, height and how much exercise you do¹³. On average, women use around 2,000 calories a day and men around 2,500, so treat figures as a rough guide, not a target to hit exactly¹⁴. Movement is one side of the balance: the more energy an activity takes, the more calories it uses, and fast walking uses more than walking at a moderate pace¹³.

Eating less than you use is how weight comes off, but it isn't realistic to keep a calorie deficit going for ever, so keeping weight off is a different job from losing it¹⁵. Small, steady changes to both eating and activity feed into the balance.

Why don't crash diets and quick fixes work?

Quick fixes tend not to last because regaining weight is common after dieting: at least one-third of dieters regain more weight than they lost¹⁰. Bigger daily calorie cuts also mean a larger share of what you lose is lean tissue, so slower loss is better for keeping muscle¹⁰. Repeated loss and regain may be linked to a higher risk of high blood pressure, abnormal blood fats and gallbladder disease, and has been associated with distress and depression⁷.

What tends to last is a plan with realistic goals, regular check-ins and kindness towards yourself, because changing habits and losing weight is not easy and takes time¹⁴. Keep activity going after weight comes off: adding it to a diet may do little for early loss, but it seems to matter more for keeping weight off⁶. If earlier attempts didn't last, that is common and doesn't mean you failed.

How does activity help with weight management?

On its own, activity has a small effect on the scale, but it changes body composition and helps keep lost weight off¹⁶. It also improves health at any weight, whether or not your weight changes⁴. In adults with overweight or obesity, regular activity, with or without weight loss, can improve blood pressure and blood fats¹⁷. European guidelines add that it reduces fat deep in the belly, builds muscle and bone, supports keeping weight stable over time, and reduces anxiety and depression⁷.

How much you need depends on your goal. 150 minutes a week improves heart health, but it is generally not enough for a meaningful amount of weight loss without eating less¹⁸. Moderate activity of 150–250 minutes a week appears to prevent weight gain and give modest loss, and more than 250 minutes a week is suggested for keeping weight off after losing it¹. For meaningful weight and body fat loss, 300–420 minutes a week is recommended⁴. Each extra 30 minutes of aerobic exercise a week may help adults with overweight or obesity slightly reduce body weight, waist size and body fat¹⁹.

No single figure suits everyone, so build up at your own pace and pair activity with eating changes.

When to check with a health professional

If you're starting exercise after a long break, it's always a good idea to see your doctor first. For an injury or a health condition, see a health professional, such as your doctor or a physio. That includes before changing your eating or activity if you have diabetes, high blood pressure, heart disease or joint pain.

Being inactive carries higher risks than the short-term risks of an exercise session, so the aim is to build up gradually rather than avoid activity²⁰.

If a muscle or joint is sore, ease off. If it persists or gets worse, see a doctor or other health professional. If you feel unusually tired, get it checked by a doctor.

Call your local emergency number for chest pain or pressure (or pain spreading to the arm, neck, jaw or back, especially with sweating or feeling sick), severe breathlessness, fainting or collapse, signs of a stroke, a serious injury, or someone who isn't safe. If you have thoughts of self-harm, contact a local crisis line (findahelpline.com lists free services in every country), along with your local emergency number.

If low mood or distress is weighing on you, talk to your doctor or a mental health service. If you have or think you may have an eating disorder, see a doctor or contact an eating disorder support service (findahelpline.com lists them by country). Sudden or strict dieting isn't advised.