Welcome , The very low-calorie diet used in the HCG diet restricts calorie intake to 500-800 calories daily. Very low-calorie diets can also cause very fast short-term weight loss. Very rapid weight loss can also increase the chance of developing gallstones. HCG can cause side effects including headache, fatigue, irritability, restlessness, depression, and fluid retention. Other side effects that have been reported include enlargement and rupture of ovarian cysts, blood clots, can cause birth defects. take fresh fruits,soya products,plenty of water,toned milk, avoid cola,coffee,fruit juices,junk foods, do exercise,cycling,swimming, get blood test for thyroid ,lipid profile,sugar, take care.