“My feet are killing me,” is a complaint you’ve probably heard often. With good reason: scientists estimate that the force on a person’s feet is about 120 per cent of their weight. This is a good reason to watch your weight: obesity subjects the supporting structures of the foot to a huge amount of stress. This can lead to plantar fascitis (inflammation of the fibrous tissue in the sole) and heel pain and can worsen hammer toes and bunions. It is also a risk factor for diabetes, say doctors.