According to Dr. Christopher J. Mosunic, a weight management and diabetes specialist at Greenwich Hospital in Connecticut writing down what you eat is one of the most powerful weight loss tools. "Keeping a food diary is like exercise; it will always help you lose [weight] if you do it consistently," he said in a news release. In observing his patients he finds that those who keep food diaries are usually very successful and their treatment programs lasting only months versus those who are not so keen on food diaries - their treatment programs can sometimes last years.