Most Asked Questions About Weight Loss and Fat Loss
Answers to 12 common weight loss and fat loss questions about dieting, exercise, supplements, and sustainable ways to reduce body fat.
- A safe, effective rate of fat loss is 0.5–1 kg per week. Faster rates increase muscle loss, nutrient deficiencies, and weight regain.
- Protein intake of 1.6–2.4g per kg of bodyweight daily during a calorie deficit reduces loss of muscle compared to lower protein intakes.
- Even proven "fat-burning" supplements only burn a 100 extra calories, whereas dietary and exercise interventions routinely exceed 1,000.
Weight loss and fat loss are the overall reduction in body mass and body fat, respectively. It is usually achieved through dietary, activity, and lifestyle changes. This article addresses the most commonly asked questions about these processes and what the evidence says about them.
1. How can I lose weight quickly?
A safe rate of fat loss is about 0.5-1 kg (or 1–2 lbs) a week1. Research shows that gradual weight loss results in more fat being lost, preserves your muscle and metabolic rate better compared to rapid weight loss2.
Faster rates of weight loss risk greater muscle wasting, nutritional deficiencies, and metabolic adaptations that increase the likelihood of regaining the lost weight. The exception is people with serious obesity or related conditions who need to lose weight fast for their health. This is done under medical supervision.
2. How many calories should I eat to lose fat?
Calorie counting is not strictly required, but creating a "calorie deficit" is likely needed to lose fat. Tracking calories may help some people achieve consistent results, as it provides awareness and accountability.
However, you can create a calorie deficit (and lose fat) through other strategies like portion control, eliminating processed foods, increasing protein and fibre intake, or eating mindfully.
The method matters less than the outcome (consuming fewer calories than you burn). Some people succeed with intuitive approaches, while others benefit from precise tracking. Choose the method you can sustain long-term.
3. Can I target belly fat through specific exercises?
No, you probably can’t selectively burn ‘subcutaneous’ body fat from specific areas of the body through targeted exercise. Where the fat loss occurs throughout the body is largely determined by genetics and hormones, not which muscles you exercise.
While some research suggests you can target fat loss around your abdomen, other studies have not3,4. However, you can certainly change the 'proportion of fat' (i.e., % fat) of any region of the body by increasing the amount of muscle you have there5.
Exercising a certain region of the body may not burn the fat directly from that region, but it can strengthen and add muscle to that area, giving the appearance that you have lost fat or “toned” that area.
4. What type of exercise is best for fat loss: cardio or strength training?
Both have important but different roles. Aerobic exercise burns more calories during the activity itself, making it more efficient at creating a calorie deficit and improving your cardiovascular health6.
Strength training preserves and builds muscle mass, which maintains your metabolic rate while you lose weight and improve your body composition (i.e., % body fat)6.
The optimal approach seems to combine both aerobic exercise for energy expenditure and strength training for your muscles. This combination provides additive benefits that neither achieves alone.
5. Can I lose fat through diet alone without exercise?
Yes, fat loss is possible through diet alone, since weight loss fundamentally requires a calorie deficit. You can achieve this deficit entirely by reducing your food intake.
However, adding exercise provides significant advantages: it increases total energy expenditure, preserves muscle mass, improves cardiometabolic health, enhances insulin sensitivity, and supports long-term weight maintenance7.
Diet-only approaches often result in greater muscle loss alongside fat loss. For optimal body composition and health outcomes, combining moderate calorie restriction with regular physical activity produces superior and more sustainable results than diet alone8.
