Mice that were restricted to a certain feeding window didn't seem to gain weight. How does that work? Energy balance is pivotal when it comes to weight loss or gain. When mice fast for a long time and humans maybe because we haven't done those very systematic study what we see is mice can burn that extra fat. They get more mitochondria and they there is a signature that gene expression signature or genetic genomic changes that happen that suggest these mice actually lose a little bit extra heat. So literally burn fat.