Avoiding mental stress could save your arteries, a University College London study of middle-aged people has found. The researchers believe this might be because stress encourages the body to produce more glucose, requiring the liver to churn out more LDL cholesterol (the bad kind) to transport it around the body. The solution? Taking up a hobby or a new language can help – both spark new connections between brain cells and help grey matter become less frazzled when faced with lots of information.