But one in 7,000 people, or one million worldwide, carry a broken copy of this gene that means the body burns calories more easily. Additionally, they measured differences in participants' body fat, muscle mass and history of liver, kidney and heart disease. The team found that people with one faulty copy of the FNIP1 gene had lower cholesterol, triglycerides, liver fat, blood sugar and body fat than non-carriers. They also had less liver and overall body fat, as well as a healthier distribution of fat. In mice fed a fatty, sugary diet, altering the gene curbed weight gain, reduced fat and improved insulin sensitivity.