A cheerful heart does good like medicine, but a crushed spirit dries the bones.
Proverbs 17:22
Research involving the mind-body connection (called psychoneuroimmunology) can be summarized in one sentence: The cerebral cortex (the thinking part of the brain) is connected to the limbic area (the feeling part of the brain) that is linked to the hypothalamus (the hormone control button of the brain) that, in turn, influences the rest of the body through a series of extremely complex microbiological connections.
When we have a thought or a feeling, our brains make chemicals known as neuropeptides. These proteinlike molecules attach to the receptor sites of blood cells allowing brain and body cells to talk to each other chemically. Immune cells that repair tissue, heal wounds, ingest bacteria, and protect us from cancer have receptors for these chemical messengers.
Messages flowing between the brain and the immune cells are transported instantaneously. When we experience joy, the white blood cells receive that message immediately. Conversely, when we are unhappy, a negative message is transmitted directly to the white blood cells. Thus, our emotional reaction influences physical health. Positive message, good health. Negative message, poor health.
What’s more intriguing, scientists have discovered certain cells in the body can make the same chemicals that the brain makes when it thinks. Our body cells make harmful or beneficial chemicals depending on our mood. A cheerful heart does good like medicine, but a crushed spirit dries the bones…is more than an aphorism. Likewise, there may be biological truth in the statements, He’s a pain in the neck, or She makes me sick.