If a hot water bottle could help people lose belly fat, then the hot water bottle manufacturers would have made millions. A hot water bottle can help relieve pain but it certainly will not help you lose belly fat. Belly fat can be lost only through a sensible diet and lots of exercise. Nothing works better. Eat plenty of fresh fruits and vegetables, whole grains, proteins and very little carbohydrates. Drink lots and lots of water. Along with that, develop a good exercise routine. Nothing can help you lose fat fast like a good combination of exercise and healthy diet.