Myths

Metabolism-boosting foods: chili, green tea and the small print

Spicy food, green tea and coffee do raise energy use slightly, but the effect is a few dozen calories a day at most, too small to replace a calorie deficit.

Lists of foods that boost your metabolism are everywhere: chili peppers, green tea, coffee, apple cider vinegar, ginger and many more. Some of these claims have a grain of truth. Capsaicin, the compound that makes chili hot, can slightly increase energy expenditure and fat burning for a short time. Caffeine and the catechins in green tea also raise metabolism a little. In laboratory studies these effects are measurable, which is why they keep appearing in headlines.

The problem is size. Across studies, the extra energy burned from realistic amounts of these foods and drinks is typically somewhere between a few and about 50 to 100 calories a day, and the effect often shrinks as the body gets used to them. That is less than a single biscuit or a small handful of nuts. Concentrated green tea extracts sold as weight-loss supplements have also been linked to rare cases of liver injury, which makes high doses a poor trade.

If you enjoy spicy food, coffee or green tea, there is no reason to stop; they can be part of a healthy diet, and spicy meals may even help some people feel satisfied with smaller portions. Just do not count on them to do the work. The factors that really change how many calories you burn are body size, muscle mass, daily movement such as walking, and training. The factor that matters most for fat loss is still the overall balance between what you eat and what you use.

More articles

Alkaline water will not change your body's pH or your performance Zone 2 cardio: why easy training builds a stronger engine Cooking oil: the hidden calories that can stall a diet Body recomposition: can you lose fat and build muscle at the same time? Gym calluses: how to keep them from tearing A warm shower before bed can help you fall asleep faster Negative-calorie foods: why celery cannot make you lose weight by itself Lifting straps: a useful tool, not cheating