Despite misconceptions, eating lemons doesn't contribute to weight loss, according to SFGate. In fact, eating too many adds to a person's calorie intake and may contribute to weight gain. The Food Network also reports that it is a myth that drinking lemon water has weight-loss effects.
The myth that eating lemons or drinking lemon juice causes weight loss is based on the belief that lemons speed up the metabolism. However, SFGate reports that no food can do that. Instead, strength training and physical activity combined with a healthy, low-calorie diet is the key. Lemons do offer vitamin C and are a relatively low-calorie food.