Getting seven and a half hours of sleep a night compared to five hours, for example, has been shown to change the amount of natural killer cells in your body by 50-60%. What are natural killer cells? They are the part of your innate immune system that fight viruses.

There was a US study which showed that 79%, nearly 80% of people, change their eating behavior in response to stress. About 45% will eat more; about 35% will eat less.

Most people, perhaps all people, use food to regulate their emotional state, and I think most of us are completely unaware of the extent to which that's true.

Every person listening to this is giving their dental health four minutes of their time a day. But how much time are you giving your mental health each day? Your physical health? And your emotional health? Are they not also worth four minutes?