Delving into the recent discovery of the brain's immune system, Dr Monty Lyman reveals the extraordinary implications for our physical and mental health. Since the birth of modern medicine, we have fundamentally misunderstood our immune system. Although the brain and the body have always been treated as separate entities - in separate hospitals - the science now shows that they are intimately linked. Startlingly, our body's immune system can access our brain and directly alter our mental health, changing our mood and behaviour. This has opened up a new frontier in human health. Drugs designed to treat arthritis have been found to treat certain kinds of depression. Incredibly, brushing your teeth properly can reduce brain inflammation, and thereby reduce the risk of dementia. And we are now beginning to understand how infections in childhood can lead to neurological and psychiatric disorders such as tics and OCD. In The Immune Mind, Dr Monty Lyman explores the fascinating connection between the mind and the immune system, as well as the body's microbiome. A researcher in the cutting-edge field of immunopsychiatry, Lyman argues we need to change the way we treat disease and the way we see ourselves. For the first time, we have a new approach to medicine that treats the whole human being.