Eating fewer carbs and calories helps overweight people lose weight by improving how their bodies process energy. This finding is from the abstract summary - full study details were not available

Whether you cut fat or carbs, if you eat the same number of calories, you’ll lose about the same amount of weight.

For athletes who need to make weight (like wrestlers or boxers), eating low-carb and high-fat for a long time might help them lose fat without losing muscle, which is safer than starving or sweating off weight quickly.

Improvements in metabolic markers and weight loss observed on extreme low-carb or carnivore diets are primarily attributable to caloric restriction and elimination of ultra-processed foods, not to the physiological properties of animal-based foods alone.

Eating fewer carbs can make you feel fuller and eat less overall — which might make it harder to gain muscle because building muscle needs extra calories.

When people eat a low-fat, high-carb diet, their body burns less fat for energy overall, which might help explain why fat builds up in the blood.