Parsley has many, many health benefits, including reducing effects of diarrhoea, improving digestion, regulating the menstrual cycle and increasing the rate of urination, which means that more matter is expelled from the body, including more calories and thus reducing weight loss. The diuretic aspect of parsley juice also means that it detoxifies the body faster than other drinks, and acts as an appetite suppressant making you feel fuller than you are.
But people who started following the keto diet noticed weight loss for a few reasons: When you eat carbs, your body retains fluid in order to store carbs for energy (you know, in case it needs it). But when you’re not having much in the carb department, you lose this water weight, says Warren. Also, it's easy to go overboard on carbohydrates—but if you're loading up on fat, it may help curb cravings since it keeps you satisfied.