Weight management worldwide: obesity, medicines and nutrition care

The scale of the challenge

The World Health Organization reports that in 2024, 45% of adults worldwide, 2.6 billion people, were living with overweight, and 940 million, 16% of all adults, were living with obesity. Among children, 35 million under five and 400 million aged 5 to 19 were overweight, including 170 million with obesity^[1]. Obesity is a chronic, relapsing disease and a major cause of type 2 diabetes, heart disease, some cancers, joint problems and poor mental health.

Prevalence varies widely. WHO estimates of adult obesity in 2022 range from 39.5% in Saudi Arabia and 36.1% in Mexico to 31.8% in the United Arab Emirates, 31.1% in South Africa, 28.2% in Brazil and 7.2% in India^[2]. Because India's population is so large, even a lower rate means a very large number of people, and type 2 diabetes appears at lower body weights in South Asian populations.

A market reshaped by medicine

Grand View Research values the global weight-management market at US$190.6 billion in 2025 and forecasts US$562.2 billion by 2033, growth of 14.2% a year^[3]. The main reason is the arrival of GLP-1 receptor agonists and related medicines that produce clinically meaningful weight loss.

IQVIA reports that 11 million unique patients in the United States were using a GLP-1 medicine across indications by the second quarter of 2025, and that before 2022 only 1.8% of patients diagnosed with obesity had started anti-obesity treatment^[4]. Uptake is highest in people with several related conditions: 29% of patients with four additional conditions filled a GLP-1 prescription within six months of diagnosis in early 2025^[5].

The Global Wellness Institute reports that the weight-loss services market contracted by 1.1% in 2024 as GLP-1 use boomed^[6]. Commercial diet programmes built only on calorie restriction are under pressure. Programmes that combine medication with nutrition, activity and behavioural support are growing.

Where nutrition care fits in the GLP-1 era

Medicines reduce appetite. They do not choose food, protect muscle or teach maintenance. That is the dietitian's work, and it has become more important, not less.

Protein and muscle

Rapid weight loss can include a significant amount of lean mass. Adequate protein spread across meals, combined with resistance exercise, helps protect muscle and function, especially in older adults. Dietitians set protein targets, plan meals people can actually eat with a reduced appetite, and use supplements where food alone is not enough.

Micronutrient adequacy

Eating much less makes it harder to reach recommended intakes of iron, calcium, vitamin D, vitamin B12, zinc and fibre. A dietitian screens intake, recommends food-first strategies and targets supplements to real gaps. See our supplements guide.

Side effects

Nausea, constipation, reflux and early fullness are common, particularly during dose escalation. Practical advice on meal size, fat content, fluids, fibre and timing helps people stay on treatment.

Maintenance and stopping treatment

Weight regain is common when medicines stop. A plan for eating patterns, activity and monitoring, agreed before treatment ends, gives people the best chance of keeping their results.

People who cannot or do not want medication

Many people cannot access medicines because of cost, supply or contraindications, and some prefer not to use them. Structured lifestyle programmes led by dietitians, including very-low-energy diets where appropriate, remain effective first-line options.

Weight management across the life course

• Children and adolescents. Family-based programmes focused on eating patterns, activity, sleep and screen time; dietitians trained in paediatrics lead this work. See our paediatric nutrition articles.
• Pregnancy and after birth. Healthy weight gain during pregnancy and support afterwards reduce risks for mother and child.
• Midlife. Menopause, work stress and rising cardiometabolic risk make this a key window for intervention.
• Older adults. The priority shifts from weight loss to preserving muscle, function and nutrition status; unintentional weight loss and malnutrition are equally serious.

Weight management as a career

Weight management is one of the fastest-growing fields for dietitians and nutritionists. Roles include:

• Specialist obesity services in hospitals and community clinics, often in multidisciplinary teams with doctors, psychologists and physiotherapists.
• Bariatric surgery programmes, before and after surgery.
• Telehealth and digital programmes that pair medication with remote nutrition coaching.
• Private practice, increasingly working alongside prescribing doctors.
• Industry roles in meal replacements, medical nutrition and digital health.

In the United States, employment of dietitians and nutritionists is projected to grow 8% from 2025 to 2035^[7]. See the full jobs outlook and the ObesityWeek and European Congress on Obesity entries on our events calendar.

For companies in weight management

Meal-replacement, medical-nutrition, digital-health and supplement companies all face the same shift: the customer may be on medication. Products that help people meet protein and micronutrient needs on a small appetite, support gut comfort and help with maintenance have a strong rationale, provided claims stay within each country's rules. Practitioner partnerships are the most credible route to market. Companies can reach dietitians through a company profile.

Professional bodies to know

The World Obesity Federation brings together more than 80 associations in over 100 countries and territories^[8]. The Obesity Society organises ObesityWeek, held in 2026 in National Harbor, Maryland^[9]. National dietetic associations, listed on our associations page, run weight-management specialist groups and continuing education.

What good nutrition care looks like

A modern weight-management consultation is more than a calorie target. A dietitian typically covers:

1. Assessment. Weight history, previous attempts, eating pattern, hunger and fullness, sleep, stress, activity, medicines, medical conditions, mental health and social circumstances.
2. Body composition and function. Where available, measures of muscle and strength, not only weight, especially in older adults and people on medication.
3. Shared goals. Health outcomes the person cares about, such as blood glucose, blood pressure, mobility, fertility or energy, alongside weight.
4. A practical eating plan. Built around the person's culture, budget and routine, with clear protein, fibre and vegetable targets.
5. Behaviour support. Planning, self-monitoring, problem solving and relapse prevention.
6. Follow-up. Regular review, adjusting the plan as weight, medication and life change.

Evidence-based dietary approaches

No single diet works best for everyone. Trials show that several patterns can produce meaningful weight loss when people can stick to them: reduced-energy Mediterranean-style eating, lower-carbohydrate approaches, higher-protein plans, meal replacements, intermittent energy restriction and, for selected people under supervision, very-low-energy diets. The best choice is the one that fits the person's health needs, preferences and long-term habits. Dietitians tailor the approach and adjust it when progress stalls.

Nutrition before and after bariatric surgery

Bariatric surgery remains the most effective treatment for severe obesity. Dietitians prepare people before surgery, guide the staged return to food afterwards, prevent and treat deficiencies of protein, iron, vitamin B12, folate, calcium and vitamin D, and support lifelong follow-up. Most people need lifelong supplements after surgery, which makes regular review essential.

Measuring success beyond the scale

Weight is one measure among many. Improvements in blood glucose, blood pressure, cholesterol, liver fat, sleep apnoea, joint pain, mood and quality of life often appear with modest weight loss of 5% to 10%. Tracking these outcomes keeps people motivated when the scale plateaus and gives a fairer picture of success.

Language and stigma

Weight stigma harms health and keeps people away from care. Professional bodies, including the World Obesity Federation, encourage person-first language, such as "a person living with obesity", respectful discussion of weight only when relevant, appropriately sized equipment, and a focus on health rather than blame. Dietitians are well placed to model this in clinics, workplaces and the media.

Building a weight-management service

For clinics and private practices, a service that combines medical review, medication where appropriate, dietitian-led nutrition care and behaviour support is now the expected standard. Practical steps include agreeing referral pathways with prescribers, setting protein and micronutrient protocols for people on GLP-1 medicines, planning group sessions to make care affordable, and measuring outcomes beyond weight. Listing the service on the member directory helps people find it.