New research conducted at Texas A&M University suggests that diets may not be one size fits all, but rather could depend on each person’s genes.

“Dietary advice, whether it comes from the United States government or some other organization, tends to be based on the theory that there is going to be one diet that will help everyone,” said David Threadgill, a professor at the Texas A&M College of Medicine and College of Veterinary Medicine & Biomedical Sciences.

Threadgill was a senior author of a new study published in the peer-reviewed journal Genetics titled “Improving Metabolic Health Through Precision Dietetics in Mice.”

The study looks at how “genetic differences influence health responses to several popular diets in mice, which are similar to humans in genetic composition.” The study fed mice several popular diets and looked at their health outcomes. The mice were similar enough genetically across the board to mimic the similarities all human share, but genetically different enough individually to mimic the differences individual people have. The mice were separated into four genetic groups.

The study used four different diets and a control to see how each mice responded. The diets were an “American-style” diet higher in fat and refined carbs, a Mediterranean diet, a Japanese diet and an Atkins or ketogenic-style diet — high in protein and low in carbs.

Though the Japanese diet is considered healthier than other diets, one of the genetic strains of mice didn’t do well with this diet.

“The fourth strain, which performed just fine on all of the other diets, did terrible on this diet, with increased fat in the liver and markings of liver damage,” said lead author William Barrington, a graduated PhD student in Threadgill’s lab.

The Atkins diet also was good for two groups, while bad for the other two.

“One became very obese, with fatty livers and high cholesterol,” said Barrington.

Another of the mice stayed lean, but their body fat increased.

“My goal going into this study was to find the optimal diet,” said Barrington said. “But really what we’re finding is that it depends very much on the genetics of the individual and there isn’t one diet that is best for everyone.”

The Mediterranean diet was also a mixed bag for the mice, some mice were healthy, while others gained weight. The American diet saw a poor reaction in most mice.

The study examined a variety of health outcomes from the diets including blood pressure, cholesterol level, liver fat, and levels of blood sugar.

“One day, we’d love to develop a genetic test that could tell each person the best diet for their own genetic makeup. There might be a geographical difference based on what your ancestors ate, but we just don’t know enough to say for sure yet.” said Barrington.