Genetics alone cannot explain why some people are fat and others thin. Other factors include what you do and what happens to you. What can be revealed with known genes is in the single digits.
- One 2015 study of 97 genetic variants known to affect body weight revealed that they could only explain less than 3% of person-to-person differences in MBI.
- Researchers are still not sure whether the FTO gene makes a protein that influences body weight.
- Many of the studies on genetics used people of European ancestry and cannot guarantee that the results will mean the same thing in other populations.