Consumption of a high-fat diet may be activating a response in the heart that is causing destructive growth and could lead to a greater risk of heart attacks, according to new research. In a paper published in Biochemical and Biophysical Research Communications, researchers looked at the effect of feeding mice a high-fat diet on oxidative stress levels on heart cells. The team from the University of Reading found that cells from the mice had twice the amount of oxidative stress, and led to heart cells being up to 1.8 times bigger due to cardiac hypertrophy which is associated with heart disease. The researchers focused on a key protein Nox2 which believed to be associated with increased oxidative stress in the heart. The study found that the mice fed a high-fat diet had twice the amount of Nox2 activity, which also led to a similar amount of reactive oxygen species (ROS), a free radical that is associated with pathological damage of the body. To check whether Nox2 was involved in causing the cardiac stress, the team compared the results with mice bred specifically to ‘knock out’ Nox2, stopping the protein from activating at a cellular level. The mice that were fed high-fat diets received 45% of their calorie consumption from fat, 20% from protein and 35% carbohydrate.