Obesity Management

Evaluation

Clinical obesity can cause severe end-organ damage and life-altering or potentially life-threatening complications, including heart attack, stroke and renal failure; therefore, people with clinical obesity should receive prompt, evidence-based treatment to improve or, when possible, achieve remission of obesity-related manifestations and prevent progression to end-organ damage.  

People with preclinical obesity should be recognized as having a variable but generally increased risk (depending on age, ethnicity, familial predisposition, body fat distribution and other factors) of developing obesity-related diseases, clinical obesity, or both. These patients should receive evidence-based health counselling, ongoing monitoring, and, when appropriate, interventions tailored to their individual risk to reduce the likelihood of developing clinical obesity or other obesity-related diseases.

Severity of Obesity  

Stage severity of obesity based on complication-specific criteria. 
 

Alternatively, the Edmonton Obesity Staging System or the King’s Obesity Staging Criteria can be used to assess the impact of obesity on physical and psychological health and function. It also helps determine the benefit of treatment.

Principles of Therapy

Treatment Goals  

The treatment goals in managing obesity are to reduce health risks and improve health by maintaining weight loss and preventing further weight gain, managing appetite and/or cravings, reducing cardiometabolic risks and improving and resolving obesity-related complications, preventing or managing existing comorbidities, restoring positive body image and self-esteem, and improving the quality of life. It is also important to address the principal cause of weight gain (treat primary and secondary causes of obesity) and focus management on both weight loss and patient-centered health outcomes (eg improved mental wellbeing, physical and social functioning, and fitness).
 
The short-term goal is a loss of 5-15% of body weight over 6 months with long-term goal of weight maintenance. Depending on the severity of obesity and ORCs, poorly controlled diabetes mellitus despite best medical treatment, cardiovascular disease, MASLD, and OSA may require ≥10% weight loss. The regain of <3 kg in 2 years and sustained reduction of waist circumference of at least 4 cm are also essential.  

Strategy  

It is important to aim for realistic goals (ie 10% body weight reduction over 6 months or not exceeding 0.5-1 kg/week) to maintain weight and prevent weight gain. Multidisciplinary team approach (combination of dietary change, physical activity, and behavioral modification) is recommended for a comprehensive and individualized weight management. Intensive interventions should be considered in obese patients with type 2 diabetes mellitus or poorly controlled ORCs (eg use of very low-calorie diet, anti-obesity agents, or bariatric metabolic surgery). Reduction of the global cardiovascular risk (eg diet modification, physical activity, weight loss, smoking cessation and control of blood glucose, blood pressure, and serum lipids) should be undertaken by patients with obesity and type 2 diabetes mellitus or hypertension. Lastly, clinicians should use shared decision-making in managing obesity to best balance potential risks and benefits of the treatment approach. 

Advantages of Weight Loss  

Weight loss promotes reduction in blood pressure, lipid levels (eg total cholesterol, TG, and LDL), risk of type 2 diabetes mellitus and all-cause mortality. There is a decrease in blood pressure <130/80 mmHg, an LDL of <3.4 mmol/L, and fasting blood glucose of ≤6 mmol/L. Since the improvement in LDL-C is modest with weight loss, cardiovascular disease risk may be reduced with early interventions that prevent and/or treat excess adiposity and increased levels of atherogenic cholesterol (eg LDL-C and/or non-HDL-C).

Weight loss also improves the patient’s cardiovascular disease risk profile with weight loss of >10-15%, produces clinical benefits in ORCs such as diabetes mellitus prevention or remission, ovulation, and regularization of menses in PMOS, reduction in inflammation and fibrosis in MASLD, improved symptomatology in OSA, OA, urinary stress incontinence, asthma, and GERD.

Pharmacological therapy

Pharmacologic therapy may be recommended in patients who failed to achieve meaningful weight loss (ie ≥5% of total body weight) and to sustain weight loss, and for patients with BMI ≥30 kg/m² or a BMI of ≥27 kg/m² with the presence of risk factors or obesity-related illnesses such as hypertension, dyslipidemia, diabetes mellitus, and OSA. The greatest effect of anti-obesity medications is on reducing TG levels with neutral to increases in HDL-C levels and marginal reductions in LDL-C levels.

Pharmacotherapy may aid compliance with dietary restriction, augment diet-related weight loss program, and help achieve weight maintenance after weight loss. The efficacy, modes of action, risks, side effects, tolerability, contraindications, drug interactions, mode of administration, previous obesity treatments, cost, access, and patient preferences are considered when choosing appropriate therapeutic options to optimize compliance and adherence to long-term management. Therapy should be individualized with medication titrated as tolerated to achieve the desired clinical effect with a dose that effectively manages ORCs. The efficacy of obesity pharmacotherapy in improving complications associated with obesity such as cardiovascular disease, heart failure with preserved ejection fraction, dyslipidemia, prediabetes, type 2 diabetes, MASLD/metabolic dysfunction-associated steatohepatitis (MASH), OSA, and OA highlights their potential benefits beyond weight reduction. Treatment selection should therefore be guided by the patient’s ORCs and the medication’s demonstrated outcome benefits, in addition to its expected weight loss efficacy.

Nutrient-stimulated hormone (NuSH) therapies (eg Liraglutide, Semaglutide and Tirzepatide) have been shown to provide benefits in lowering cardiovascular risk factors and improving cardiovascular outcomes, as well as reducing MASLD and chronic kidney disease progression. NuSH therapies target the hormonal pathways which control appetite (eg hunger, satiety, satiation and cravings) and allow titratable dosing that minimizes side effects and maximizes weight loss. Their usage may require adjustments in the management of ORCs, including de-escalation of antihypertensives to prevent hypotension, adjustment of diuretics for heart failure to prevent intravascular depletion and adjustment of antidiabetic medications for type 2 diabetes mellitus to prevent hypoglycemia.  

Central adiposity measurements (eg waist circumference, WHR, and/or waist-to-height ratio) along with ethnicity-specific BMI thresholds and/or ORCs may be used to help determine when to start pharmacotherapy. It is important to check for the efficacy and safety at least monthly for the first 3 months of pharmacotherapy. Successful pharmacotherapy is considered if at least 2 kg (4.4 lb) weight loss is achieved in the first 4 weeks after starting treatment, otherwise, re-assessment should be considered. Pharmacotherapy, together with lifestyle modifications and physical activity, produces an average weight loss of 10-20% with a reduction in cardiovascular events, type 2 diabetes mellitus, MASLD, and OSA. For successful weight maintenance, weight regain should be <3 kg (6.6 lb) in 2 years and a sustained reduction in waist circumference of at least 4 cm.  

Since obesity is a chronic disease, treatment approach should be long-term. The United States Food and Drug Administration (US FDA)-approved agents for chronic weight management include Orlistat, Phentermine/Topiramate, Naltrexone/Bupropion, NuSH therapies (eg Liraglutide, Semaglutide, and Tirzepatide), and Setmelanotide, according to relevant indications. Clinical trials consistently show that discontinuation of therapy is followed by clinically significant weight regain and loss of associated health benefits; therefore, effective and well-tolerated treatment should generally be continued long term, provided that the benefits outweigh the risks and there are no safety concerns. Treatment discontinuation should not be routine solely because weight loss goals have been achieved; maintenance treatment and lifestyle support should continue to reduce the risk of weight regain.  

If weight loss of ≥5% has not been achieved after 3 months on a therapeutic dose, factors contributing to a suboptimal response should be reassessed. These may include access, cost, adequacy of dosing, challenges in compliance, barriers to health behavior change, and psychosocial and medical issues. If treatment goals have not been achieved on the maximum tolerated dose, consider adding or substituting another obesity medication or intervention. Referral is considered to an obesity medicine specialist if side effects restrict dose escalation or if weight loss is <5% at the maximum tolerated dose. In cases of excessive weight loss, medication should be reduced to a dose at which the patient is able to regain and maintain sufficient weight. However, medication may need to be stopped in some cases. It may also be necessary to evaluate the presence and severity of any gastrointestinal side effects from treatment and determine whether further investigations for other potential causes of the weight loss are necessary. Acute illness should be prioritized for treatment (eg markedly increased blood glucose and/or blood pressure, severe dyslipidemia, acute thrombosis, cardiovascular disease or cancer) with concomitant treatment of obesity. Medications that are not associated with weight gain should be chosen for the treatment of other health conditions. Pharmacotherapy for obesity is not recommended in pregnant or breastfeeding women or in women who are trying to conceive. There is no available evidence to guide when pharmacotherapy for obesity should be discontinued before conception. The use of compounded medications for obesity management is not recommended due to concerns and uncertainties regarding content, safety, quality, efficacy and lack of regulation.
 
Centrally Acting Anti-Obesity Agents¹  

Glucagon-Like Peptide-1 (GLP-1) Receptor Agonists  

Liraglutide  

Liraglutide is an early-generation, once-daily, injectable peptide GLP-1 receptor agonist. It is indicated as an adjunct to a reduced-calorie diet and increased physical activity for chronic weight management of patients who are obese or overweight with at least one weight-related comorbidity (eg type 2 diabetes, dyslipidemia or hypertension). This improves satiety, reduces hunger, and slows gastric emptying. The average weight loss is 8%. It reduces HbA1c, blood pressure, insulin resistance, lipid levels, risk of stroke, and use of oral glucose-lowering agents in patients with type 2 diabetes mellitus. The efficacy of Liraglutide 3 mg for weight loss is supported by the Satiety and Clinical Adiposity – Liraglutide Evidence (SCALE) Obesity and Prediabetes trial program.  

Semaglutide  

Semaglutide is a new-generation, once-weekly injectable peptide GLP-1 receptor agonist. It is indicated as an adjunct to a reduced-calorie diet and increased physical activity for chronic weight management of patients who are obese or overweight with at least one weight-related comorbidity (eg type 2 diabetes, dyslipidemia or hypertension). It is also indicated for the reduction of risk of major cardiovascular events in individuals with established cardiovascular disease and obesity or who are overweight and for the treatment of non-cirrhotic MASH in people with moderate to advanced liver fibrosis. It improves satiety, reduces hunger, and slows gastric emptying. It also reduces HbA1c, blood pressure, lipid levels, and the risk of stroke. Its use is supported by the Semaglutide Treatment Effect in People with obesity (STEP) trial programs – Semaglutide 2.4 mg produces greater mean weight loss than Liraglutide 3 mg. In patients with type 2 diabetes and chronic kidney disease, Semaglutide reduced the risk of clinically important kidney outcomes and cardiovascular death in the FLOW (Evaluate Renal Function with Semaglutide Once Weekly) trial, demonstrating renal and CV benefits beyond glycemic control. 

Orforglipron  

Orforglipron is a once-daily, oral non-peptide (small molecule) GLP-1 receptor agonist. It is indicated in combination with a reduced-calorie diet and increased physical activity to reduce excess body weight and maintain weight reduction long term in adults with obesity or adults with overweight in the presence of at least one weight-related comorbid condition. It improves satiety, reduces hunger, and slows gastric emptying. It also demonstrated significant, dose-dependent, sustained weight loss, with phase 3 trials showing a mean body weight reduction of 12-15% in non-diabetic adults and 10-12% in adults with type 2 diabetes mellitus over 72 weeks. It reduces HbA1c and has shown improvements in blood pressure and lipid levels in patients with type 2 diabetes mellitus. Orforglipron’s efficacy is being evaluated in the phase 3 ACHIEVE and ATTAIN clinical trial programs.
 
GLP-1 Receptor and Glucose-dependent Insulinotropic Polypeptide (GIP) Receptor Agonist  

Example drug: Tirzepatide  

Tirzepatide is indicated for chronic weight management as an adjunct to a reduced-calorie diet and increased physical activity in adults with an initial BMI of ≥30 kg/m² or ≥27 kg/m² with at least one weight-related comorbid condition (eg hypertension, dyslipidemia, type 2 diabetes mellitus, OSA, or cardiovascular disease). It is also indicated for the treatment of moderate to severe OSA in adults with obesity as an adjunct to a reduced-calorie diet and increased physical activity; its use may reduce OSA severity in conjunction with weight loss and complements established treatments such as positive airway pressure (PAP) therapy. It improves satiety, reduces hunger, and slows gastric emptying. It also reduces HbA1c, blood pressure, and lipid levels. Tirzepatide’s efficacy for weight loss is supported primarily by the SURMOUNT clinical trial program, particularly SURMOUNT-1. Tirzepatide has demonstrated benefits in adults with MASH and liver fibrosis, including MASH resolution without worsening of fibrosis and improvement in fibrosis without worsening of MASH. Although emerging evidence suggests that Tirzepatide may reduce hepatic fat more than Semaglutide, this comparative claim should be considered investigational unless supported by direct head-to-head evidence. Patients are advised regarding the potential risk of medullary thyroid carcinoma and symptoms of thyroid tumors.
 
Naltrexone/Bupropion  

Naltrexone is an opioid receptor antagonist while Bupropion (an antidepressant) is a dopamine and norepinephrine reuptake inhibitor. They are adjuncts to a reduced-calorie diet and increased physical activity for weight management of patients with a BMI of ≥30 kg/m² or ≥27 kg/m² with at least one weight-related comorbid condition (eg type 2 diabetes mellitus, dyslipidemia, or hypertension). They reduce food craving and appetite; their anorectic effect may be a result of sustained activation of anorexigenic neurons in the hypothalamus. In a clinical study, results from the Control of Eating Questionnaire (CoEQ) showed improvement in craving control. They also decrease glucose levels, insulin resistance, and lipid levels, and decrease the requirement for glucose lowering drugs in type 2 diabetes mellitus. They may also be used in patients with obesity and depressed mood.

Norepinephrine Agents²  

Example drugs: Mazindol, Phentermine, Phentermine/Topiramate 

Norepinephrine agents enhance catecholamine neurotransmission leading to increased sympathetic activity and reduced appetite. They are not recommended in patients with uncontrolled hypertension or a history of heart disease.  

Phentermine is the most commonly used noradrenergic agent for the treatment of obesity. It does not affect dopamine neurotransmission, hence, there is little potential for abuse. It is recommended for short-term use (<12 weeks) only and is no longer recommended for long-term treatment of obesity. It reduces appetite, total cholesterol, and LDL-C. It should be used with caution in patients with anxiety disorders and should closely monitor for changes in behaviors and moods. Severe mental depression may result from abrupt discontinuation after prolonged high-dose intake; hence, it is recommended to gradually withdraw Phentermine therapy.  

Phentermine/Topiramate is approved for long-term use in the management of obesity in combination with a reduced-calorie diet and lifestyle modifications. They increase satiety, reduce appetite and caloric intake, and increase energy expenditure and decrease energy efficiency and caloric intake. The average weight loss seen is 10%. 
 
¹Lorcaserin has been withdrawn from the market after a safety clinical trial demonstrated an increased occurrence of cancer in treated patients.
²Amphetamines are no longer recommended for treatment due to their potential for abuse. Some agents (eg Benzphetamine and Phendimetrazine) are considered to be of high potential for abuse and are not recommended.  

Setmelanotide  

Setmelanotide is a melanocortin 4 receptor (MC4R) agonist which restores impaired MC4R activity caused by extremely rare genetic deficits leading to hyperphagia and early-onset severe obesity. It is indicated for chronic weight management in patients ≥6 years old with monogenic or syndromic obesity due to Bardet-Biedl syndrome (BBS) or genetically confirmed biallelic pro-opiomelanocortin (POMC), proprotein convertase subtilisin/kexin type 1 (PCSK1) or leptin receptor (LEPR) deficiency due to variants in POMC, PCSK1, or LEPR genes considered pathogenic, likely pathogenic, or of uncertain significance. It is undergoing evaluation as a possible treatment for other monogenic forms of obesity associated with impaired MC4R signaling, as well as for acquired hypothalamic obesity. Weight loss is evaluated after 12-16 weeks of treatment in patients with POMC, PCSK1 or LEPR deficiency or after 1 year in patients with BBS.

Peripherally Acting Anti-Obesity Agent  

Orlistat  

Orlistat is the only lipase inhibitor approved for the management of weight loss. It works by inhibiting pancreatic lipase, preventing fat hydrolysis into absorbable fatty acids and thereby decreasing fat absorption. It does not target appetite or satiety mechanisms.

It is indicated for the treatment of patients with a BMI of ≥30 kg/m², or patients with a BMI of ≥27 kg/m² with associated risk factors (eg type 2 diabetes, hyperlipidemia, and hypertension). It may be used in patients who prioritize modest amount of weight loss and are not bothered by the possibility of gastrointestinal adverse effects. It has been shown to reduce blood pressure and glucose levels and improve lipid profile.

When 120 mg is taken immediately before, during or up to 1 hour after each main meal, 1/3 of dietary fat ingested is excreted in stool, reducing fat and calorie intake. It also inhibits digestion of TG. Current data noted rare cases of severe liver injury with the use of this medication.  

Weight Loss Efficacy  

Weight loss efficacy should be reported using mean and, where available, median percentage weight loss, together with the proportion of participants achieving clinically meaningful thresholds, including ≥10%, ≥15%, ≥20% and, when available, ≥25% weight loss. Outcomes should be interpreted in the context of treatment dose, duration, comparator and study population.

Reference: Pedersen SD, Manjoo P, Dash S, et al. Canadian adult obesity clinical practice guideline: pharmacotherapy for obesity management in adults: 2025 clinical practice guideline update. CMAJ. 2025 Aug 10;197(27):E797-E809.

Other Agents   

Glucose-Lowering Medications with Weight Effects

Metformin may help limit weight gain or produce modest weight reduction, in addition to improving glycemic control. Consider giving Metformin and psychological therapy for weight gain prevention to patients with severe mental illness who are receiving antipsychotic drugs associated with weight gain. Sodium-glucose co-transporter 2 (SGLT2) inhibitors promote urinary glucose excretion and may result in modest weight loss, with additional benefits on glycemic control, blood pressure reduction, and cardiovascular and renal protection. Pramlintide, an amylin mimetic, may result in modest weight loss and improves postprandial glycemic control when used as an adjunct to Insulin. 

Lisdexamfetamine and Topiramate  

Lisdexamfetamine and Topiramate may be considered as adjunctive therapeutic agents to psychological treatment in overweight or obese patients with binge-eating disorder.  

Dietary Supplements and Herbal Preparations  

There is insufficient evidence to recommend dietary supplements and herbal preparations for the management of obesity. They may contain unpredictable amounts of active ingredients, have unpredictable efficacy, and unknown safety profiles. 

Emerging Pharmacotherapies  

Amycretin is a unimolecular peptide with agonist activity towards GLP-1, amylin and calcitonin receptors that targets regions involved in appetite regulation to enhance satiety and reduce energy intake. CagriSema, a combination of Cagrilintide and Semaglutide, combines complementary mechanisms of action, providing synergistic and more potent effects on weight loss. The Phase 3 REDEFINE trials showed that once-weekly CagriSema produces clinically meaningful weight loss and improves glycemic control, with greater efficacy than its individual components and benefits extending to people with obesity and type 2 diabetes. Retatrutide is a triple agonist of the GLP-1, GIP and glucagon receptors designed to modulate multiple biological pathways and potentially provide greater weight reduction and metabolic benefits. The Phase 3 TRIUMPH-4 trial demonstrated that Retatrutide produced substantial weight loss in adults with overweight or obesity and knee osteoarthritis, with the 12-mg dose achieving an average reduction of up to 28.7% according to the efficacy estimand. Long-term safety data of these emerging pharmacotherapies remain limited, and optimal treatment duration and strategies for maintaining weight loss have not yet been established.

*Pharmacotherapy for obesity should be given together with lifestyle therapy and health behavior changes.
Reference: Pedersen SD, Manjoo P, Dash S, et al. Canadian adult obesity clinical practice guideline: pharmacotherapy for obesity management in adults: 2025 clinical practice guideline update. CMAJ. 2025 Aug 10;197(27):E797-E809.

Nonpharmacological

Weight loss through lifestyle changes leads to about a 5% weight reduction and is linked to decreases in blood pressure, TG and fasting glucose, as well as a lower incidence of type 2 diabetes mellitus.

Lifestyle Therapy

Diet or Calorie Restriction  

Energy expenditure should be more than total energy intake (caloric deficit). Patients are generally advised to decrease the portion size of food, choose low energy-dense foods and drinks, avoid between-meal snacks, ultra-processed food, sugar-sweetened beverages, or refined carbohydrates, limit sodium and alcohol intake, not to skip breakfast and to avoid nighttime eating, and reduce binge eating. Emphasize the need for a balanced, reduced caloric intake and adherence to dietary therapy for initial weight loss and maintenance. Macronutrient recommendations should be individualized according to the patient’s nutritional needs and preferences. Consumption of low-fat, reduced-calorie diets are important for a successful weight loss for 12 months.  

A calorie reduction of 500-1000 kcal/day from the usual intake should be done to achieve a weight loss of 0.5-1 kg/week (1-2 lb/week). Every 24 kcal/day reduction will result in the long term in approximately 1 kg loss in body weight, or a 15-30% reduction from habitual caloric intake can result in 5-10% weight loss and long-term maintenance. An intake of 1200-1500 kcal/day for most women and 1500-1800 kcal/day for most men can help achieve the treatment goals. Calorie reduction may also be simplified by using a 9-inch plate with half of the plate composed of vegetables and fruits and the other half divided between carbohydrates and protein.  

The amount of fat reduced will depend on each specific country’s national standard. Total fat should be ≤30% of the total calories (trans fat <1%, saturated fat 7-10%, monosaturated fat up to 15% of total calories) and with most fats coming from fish, nuts, and vegetable oils.  

Carbohydrates should comprise 55% of the total calories. Complex carbohydrates from fruits, vegetables, and whole grains are preferred.  

Protein should be ≤15% of the total calories. It should be derived from plant sources or lean animal sources.  

Fiber should get ≥25-35 g/day. It delays gastric emptying causing a feeling of fullness and decreased appetite or hunger. It also helps decrease absorption of fat and cholesterol. It may be obtained from oatmeal, whole wheat bread, rice, beans, citrus fruits, carrots, cauliflower, strawberries, peaches, and apple with skin.  

For vitamins and minerals, the following are the recommended daily intakes:

• Calcium: 1000 mg/day total daily intake which can be derived from diet with or without supplementation (especially for women at risk of osteoporosis)
• Vitamin D: 10-20 mcg/day

Modified Diets  

Clinically meaningful weight loss and improvement in the function of the adipose tissue can be achieved with reduced calorie intake regardless of macronutrients.  

Low-Calorie Diet (LCD) is a food-based approach intended to lower caloric intake by 500 kcal/day from the maintenance requirement regardless of macronutrient composition. The energy content is 800-1200 kcal/day and may require meal replacements to meet caloric and nutritional targets. An average of 8-10% reduction in total body weight was noted over a 6-month period.  

Very Low-Calorie Diet (VLCD) comprised of a caloric intake of <800 kcal/day regardless of macronutrient composition. It uses calorie-controlled, nutritionally balanced, vitamin or mineral-fortified pre-prepared meal replacements utilized as the only nutrient source. It is used for a maximum of 12-16 weeks and monitored by experienced practitioners. It can be extended or used intermittently over longer periods of time at the discretion of the supervising healthcare provider.  

VLCD is indicated in moderately to severely obese patients who are motivated but have failed with conservative methods, or in patients with a BMI of 27-30 kg/m² who have medical conditions that might respond to rapid weight loss. Weight regain after rapid weight loss is not faster than gradual weight loss.  

Modified diets can be done by a certified nutritionist or dietitian, and they need to be clinically supervised. Physicians should also consult with nutrition professionals when prescribing a particular weight loss diet, including individualized medical nutrition therapy, that will address the patient’s needs. Patients with ORCs need to work with their physicians to adjust chronic medications.  

Other Dietary Strategies  

Other dietary strategies may be effective when individualized and sustainable. The Dietary Approaches to Stop Hypertension (DASH) diet and the Mediterranean diet are safe and recommended for individuals wanting to lose weight. DASH diet was developed to reduce blood pressure and it emphasizes intake of foods low in sodium, cholesterol, and saturated fats (eg fruits, vegetables, and low-fat dairy foods). The Mediterranean diet, which is associated with improved long-term weight maintenance and cardiovascular risk reduction, requires a high consumption of olive oil, legumes, grains, cereals, fruits, vegetables, and moderate to high consumption of fish and dairy products. .  

Intermittent fasting involves fasting and non-fasting periods (eg eating normally for 5 days and then taking in much less energy/calories on the remaining 2 days of the week). Time-restricted feeding is also a form of intermittent fasting wherein food intake is limited to ≤8 hours daily. Fasting-related concerns include mood changes, fatigue, or dizziness. Cardiovascular events can be provoked and aggravated in the elderly. It shows promise for obesity treatment, but further research is needed before using it in the long term.  

Carbohydrate-limiting diets such as the Atkins and ketogenic diets derive a major portion of the caloric intake from fat sources. Adverse effects include potential increase in LDL cholesterol levels and development of kidney stones.  

Paleo diet, also referred to as the caveman-like diet, is high in protein and low in carbohydrates and usually excludes grains, legumes, and dairy products. It may encourage consumption of large amounts of meat, while inadequate intake of other foods, which may lead to the development of anemia, osteoporosis, type 2 diabetes mellitus, or hypertension.  

Patients are recommended to seek professional advice before starting any form of diet.  

Physical Activity Interventions  

There is very strong evidence supporting the role of regular physical activity in the prevention and management of risk factors for cardiovascular disease and diabetes mellitus. The benefits of physical activity include reduced weight and fat mass, improved metabolic profile, increased cardiovascular fitness (improved functional status in patients with heart failure with preserved ejection fraction), and improved well-being.  

It can be done in the form of daily unstructured physical activity or structured physical activity featuring aerobic and/or resistance training. Moderate- to vigorous-intensity aerobic exercises (eg swimming, table tennis, 4.3-6.4 kph brisk walking, 16 kph cycling) are recommended for 30-60 minutes, 5 days/week (>150 minutes a week) and could be done as:

• 30 minutes/day for cardiovascular fitness
• At least 150 minutes/week combined with resistance exercise 2-3 times/week to increase muscle strength
• ≥150 minutes/week to maintain health and prevent diseases
• 150-420 minutes/week to achieve weight loss since a dose-response relationship exists between volume of exercise and the amount of weight loss
• 200-300 minutes/week to maintain weight loss
• A total of 10-60 minutes/day is recommended with gradual increase over time for unfit or inactive individuals

Resistance training using the major muscle groups in single-set exercises may also be advised 2-3 times/week to maintain weight or modestly increase mobility and muscle or fat-free mass. One may consider 5,000-10,000 steps per day as a starting aerobic physical activity in those who are physically inactive or with limited mobility. Appetite is suppressed during and immediately after exercise but increases after an hour. Activity should be tailored to the patient’s age, ability (eg fitness level, physical impairments), and cardiovascular risk. An increase in daily activity and reduction in sedentary time should also be encouraged (eg walking, climbing stairs). 

Obesity_Management

• Enhancement of communication and avoidance of stigmatization
• Psychoeducation which emphasizes on achieving behavioral and psychological goals to improve health, function, and quality of life
• Motivational interviewing and behavioral interventions
  • Motivational interviewing includes patient engagement, focusing on 1 behavior at a time and evoking the patient's internal motivation
  • Behavioral strategies help improve adherence to lifestyle intervention programs
• Psychological interventions which include cognitive behavioral therapy (CBT) and Acceptance and Commitment therapy
  • CBT combined with diet or exercise resulted in a greater weight loss compared to diet or exercise alone
  • Acceptance and Commitment therapies center on value-directed actions and commitment to multicomponent behavioral interventions

Information and communication technology (ICT)-based weight loss tools (eg structured websites, internet-enabled mobile phone applications) which allow patients to track and monitor their behaviors online compared to standard non-ICT-based interventions were found to significantly increase weight loss, decrease total energy and saturated fat intake, and have minimal but positive effect on physical activity. ICT-based interventions must include tailoring, goal setting, self-monitoring, social support, and targeted feedback.  

Comorbidities  

Prevention and treatment of comorbidities are recommended. Regular screening for obesity-related cancers is advised in individuals with obesity.

Surgery

Bariatric and Metabolic Surgery  

Bariatric and metabolic surgery are considered the most effective methods to reduce and maintain weight in severely obese patients. They are indicated for severely obese patients who were unable to maintain weight loss by non-surgical methods. They are associated with average weight losses of between 16-35% in up to 8 years depending on the type of surgical procedure. Laparoscopic approach is the first treatment of choice.  

Based on long-term data, surgery has been shown to reduce overall mortality over a 15-year period compared to conservative medical treatment. Surgery improves ORCs and quality of life and decreases cardiovascular mortality and morbidity. Metabolic surgery should be done in high-volume centers with well-informed and experienced multidisciplinary teams. Strict selection criteria should be applied. It may have partial weight regain in up to 35% of patients after 5 years in patients with BMI >35 kg/m².  

The 2022 American Society for Metabolic and Bariatric Surgery (ASMBS), the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO), and the 2026 American Diabetes Association (ADA) stated that metabolic surgery may be considered in the management of patients with BMI ≥30 kg/m² (≥27.5 kg/m² in Asian Americans) and ORCs (eg type 2 diabetes mellitus, hypertension, dyslipidemia, OSA, cardiovascular disease, asthma, fatty liver, chronic kidney disease, GERD, PMOS, and bone and joint diseases). 

The second Diabetes Surgery Summit (DSS-II) recommends metabolic surgery for the treatment of type 2 diabetes mellitus Asian patients with a BMI ≥37.5 kg/m² and a BMI 32.5-37.4 kg/m² when optimal lifestyle and medical treatment are inadequate to control hyperglycemia. It also considers metabolic surgery for patients with BMI 32.5-37.4 kg/m² with adequate glycemic control and BMI 27.5-32.4 kg/m² with poor glycemic control despite optimal lifestyle and medical treatment (including injectable medications and Insulin). 

The IFSO - Asia Pacific Chapter (IFSO-APC) consensus statements in 2011 recommend bariatric surgery in the following Asian patients with:

• BMI ≥35 kg/m² with or without comorbidities 
• BMI ≥30 kg/m² inadequately controlled by lifestyle changes or medical therapy for the treatment of type 2 diabetes mellitus or metabolic syndrome
• BMI ≥27.5 kg/m² as non-primary treatment alternative for inadequately controlled type 2 diabetes mellitus or metabolic syndrome

The contraindications to bariatric or metabolic surgery are current alcohol or substance abuse, unstable psychological conditions, esophageal dysmotility, inflammatory bowel disease, chronic pancreatitis, bile duct pathology, portal hypertension, active malignancy, regular use of non-steroidal anti-inflammatory drugs (NSAIDs), and history of gastric cancer. Relative contraindication includes inability to comply with postoperative nutritional changes or follow-ups.  

The commonly performed bariatric surgery procedures in Asia include sleeve gastrectomy, Roux-en-Y gastric bypass (RYGB), adjustable gastric band (AGB), and biliopancreatic diversion with duodenal switch (BPD-DS). Notably, at 1 year, the average weight loss is 23% for sleeve gastrectomy and 31% for RYGB; AGB produces less weight loss compared to sleeve gastrectomy and RYGB. Endoscopic bariatric procedures include intragastric balloon and endoscopic sleeve gastroplasty (ESG). The average weight loss at 1 year is 12-15% for intragastric balloon and 13-16% for ESG.

Obesity_Surgery