Drinking water throughout the day is recommended to keep the body hydrated. More importantly, avoid eating oily and junk foods to avoid the build-up of unhealthy fat. Remember that exercise is also vital to promote fast weight loss. Some people complain about insomnia after taking fat-burning supplements during the day. It’s a 3-in-1 dietary supplement designed to improve sleep patterns, boost your energy levels, and stimulate fat-loss even when you sleep.