Grocery list experiment shows that making mental shopping lists doesn’t always lead to healthier purchases

“Contrary to the advice given by legions of nutritionists and diet guides, making a shopping list may actually increase a shopper’s chance of selecting unhealthier food options. According to a study conducted at Duke University and published in the ‘Journal of Consumer Research,’ the mental effort that it takes to make a shopping list may actually lead to decreased impulse control.”

This looks flawed to me.