What is the best approach to achieve weight loss?

How to Lose Weight

To lose weight effectively, create a caloric deficit by consuming 1,200-1,500 kcal/day for women or 1,500-1,800 kcal/day for men, combined with at least 150 minutes per week of moderate-intensity physical activity, aiming for 0.5-1 kg (1-2 pounds) weight loss per week. 1

The Fundamental Principle

• Weight loss requires an energy deficit—this is non-negotiable. 1
• The specific macronutrient composition of your diet matters far less than maintaining a consistent caloric deficit. 1, 2
• Target a 500-750 kcal/day deficit below your maintenance needs to achieve steady weight loss. 1

Dietary Strategy Selection

Any of the following approaches will work if you maintain the caloric deficit—choose based on what you can sustain long-term: 1

• Mediterranean diet with caloric restriction (strongest evidence for metabolic benefits) 1, 3
• Low-carbohydrate diet (initially <20g/day carbohydrate, no formal calorie counting but achieving deficit) 1
• Low-fat diet (20-30% of calories from fat) 1
• Higher-protein diet (25% of calories from protein) 1
• Low-glycemic-load diet 1

Critical Implementation Details

• Reduce dietary fat intake as the most practical way to cut calories, since fat is calorie-dense at 9 kcal/gram. 1
• Eliminate liquid calories completely—sodas, juices, and alcohol provide calories without satiety. 1, 3
• Use portion-controlled servings or meal replacements to prevent underestimating caloric intake, which obese individuals commonly do. 1
• Increase consumption of high-water-content, low-energy-density foods (vegetables, fruits) to enhance satiety while maintaining caloric deficit. 1

Physical Activity Requirements

Start with 150 minutes per week of moderate-intensity aerobic activity (30 minutes daily, 5 days/week), then progress to 200-300 minutes per week for weight loss maintenance. 1, 3

• Physical activity alone produces minimal initial weight loss but is essential for maintaining weight loss long-term. 1
• Aerobic exercise (brisk walking, cycling) is the foundation—it preferentially reduces visceral fat even with modest weight loss. 3
• Add resistance training 2-3 times weekly to preserve lean muscle mass during weight loss. 3
• Target 10,000 steps daily in addition to structured exercise sessions. 3

Behavioral Modification Components

High-intensity behavioral intervention (≥14 sessions over 6 months) produces the best outcomes. 1

• Self-monitor daily: Keep food logs, track physical activity, and weigh yourself at least weekly. 1, 3
• Set SMART goals (specific, measurable, achievable, realistic, timely) rather than vague intentions. 3
• Modify your environment to reduce food cue exposure (stimulus control). 3
• Schedule regular follow-up visits (at least monthly) with a trained interventionist or healthcare provider. 1

Expected Outcomes and Timeline

• Aim for 5-10% initial body weight loss over 6 months—this produces clinically meaningful improvements in blood pressure, lipids, and glucose control. 1
• Most weight loss occurs in the first 6 months; expect 1-2 kg/year gradual regain thereafter without continued intervention. 1
• After reaching your goal, increase physical activity to 200-300 minutes/week to maintain weight loss. 1

Common Pitfalls to Avoid

• Very-low-calorie diets (<800 kcal/day) cause rapid weight loss but lead to weight regain when stopped—use only under medical supervision for short periods. 1
• Very-low-carbohydrate diets (<130g/day) lack long-term safety data and eliminate important food sources—not recommended for sustained use. 4
• Relying on exercise alone without dietary changes produces minimal weight loss. 1
• Underestimating portion sizes and caloric intake when self-selecting foods—use portion control or meal replacements initially. 1

Pharmacological Adjuncts (When Appropriate)

If lifestyle intervention alone is insufficient after 3-6 months, consider FDA-approved medications: 1, 3

• Orlistat: Blocks fat absorption; take 1 capsule with each fat-containing meal (maximum 3 daily), combined with reduced-calorie, low-fat diet. 5
• GLP-1 receptor agonists (semaglutide, liraglutide): Superior visceral fat reduction for patients with obesity and metabolic complications. 3

The Bottom Line

No single diet is superior—the key is creating and maintaining a sustained caloric deficit through an approach you can adhere to long-term. 1, 2 The combination of caloric restriction (1,200-1,800 kcal/day depending on sex), regular physical activity (150-300 minutes/week), and behavioral support produces 5-10% weight loss in 6 months, which significantly improves metabolic health regardless of which specific diet you choose. 1