Identical twins Ross and Hugo Turner, 36, both ate three meals per day plus two snacks, which was the equivalent of around 3,500 calories in total.
HUGO followed a high fat, low-carb diet and began consuming most of his calories in olive oil, butter, nuts, eggs and avocado.
Meanwhile, ROSS began eating more high-carb foods such as pasta and rice and decreased his high-fat food intake.
They also spent the 12 weeks doing similar workouts sessions, which involved a mixture of cardio and strength training. They rested every three days.
Both the brothers continued to eat whole protein sources like chicken and protein shakes. [Ed: This means both were consuming additional fat.]
High-carb ROSS gained 2.2 pounds of muscle and lost two pounds of fat after following the high-carb diet. He also lowered his cholesterol and managed to decrease his internal visceral fat (the most dangerous type linked to chronic diseases) from 11.5 percent to 11.1 percent.
High-fat HUGO gained 6.6 pounds of muscle, lost only half a pound of fat, saw no changes in his cholesterol levels and increased his internal visceral fat from 11.4 percent to 12.6 percent.
Visceral fat is belly fat found deep within the abdominal cavity. It surrounds important organs, including the stomach, liver and intestines.
As well as losing more fat, high-carb ROSS also performed better in cardiovascular tests while high-fat HUGO noted that he performed worse and felt more fatigued during intense exercises.
Data collected by University of Loughborough researchers also showed that high-carb ROSS was able to run for longer by the end of the experiment while high-fat HUGO struggled.
The researchers concluded that, overall, the high-carb diet came out on top in this case.
https://www.businessinsider.com/fat-loss-diet-high-carb-energy-twin-experiment-2025-2