According to this, it is: ‘Four hours to walk off pizza calories’ warning works, experts say – BBC News. For example, if you were to buy a pizza or a chocolate bar, they argue that…
Appreciating it would take four hours to walk off the calories in a pizza or 22 minutes to run off a chocolate bar creates an awareness of the energy cost of food, they say.
That’s true. But it’s also not a great comparison. It’s pretty much a given that exercise is not a great way of losing weight, so most foods will come across as requiring a lot of exercise to work off the food. And it may be a lot more exercise than most people do. This will just end up shaming more people than it benefits.
I think a better approach would be to highlight what percentage of your recommended caloric allowance a selection of food is. I believe this would be much better. Foods have something similar already: they tell you what percentage of vitamins, fibre, etc. a selection of food provides for your diet. They could do the same thing with calories. Hey, on some days when you hadn’t had much to eat, something that provides you 50% of your daily calories may be fine.
No matter what, providing health guidance is never simple. But if I had to decide, I’d go with percentages.