If someone were to suggest that helping an elderly person to carry their shopping could cut the risk of heart disease, I think most people's minds would jump to the thought of the exercise they'd be getting.
That's a fair enough thought, especially if the bags are heavy and you carry them on a regular basis.
But there might be another reason that has less to do with exercise and more to do with the act of kindness itself.
That reason lies with the hormone oxytocin, well known for its role in childbirth. Many women receive Pitocin, a commercial form of oxytocin, to induce labour. It also plays a role in lactation to facilitate breastfeeding.
It plays a key role in the brain as a neurotransmitter and facilitates social bonding. It has been found to help children and adults with autism better recognise emotions.
We produce oxytocin when we bond with each other. Having quality relationships increases its levels. But another way to bond with someone is through a simple act of kindness. And this might just be good for the heart.
Exciting research has revealed that oxytocin plays a powerful role throughout the cardiovascular system.
As well as being produced in the brain, it is also produced in the heart and travels throughout our blood vessels. There, it is believed to increase nitric oxide production (not nitrous oxide, which is laughing gas!). The nitric oxide then dilates our blood vessels, reducing blood pressure.
Many people will have heard of nitric oxide. Glyceryl trinitrate is given to reduce the pain of angina because it dilates the coronary arteries and improves blood supply to the heart. It does this because it is converted to nitric oxide in the body.
The "cardioprotective" role of oxytocin was actually first put forward in the early 1990s when researchers observed that lactating women tended to have lower blood pressure. Lactation is a time when there is lots of oxytocin production in the female body. Putting two and two together, it wasn't long before researchers began examining its effects on the heart and blood vessels.
Research now shows that oxytocin also has a powerful effect on free radical and inflammation levels, which are two of the central culprits in coronary artery disease. Excess inflammation, for instance, leads to a buildup of arterial plaque that can result in a heart attack.
In a groundbreaking study, researchers at the University of Miami placed blood vessel cells under stress in the lab, where the stress was meant to simulate stress conditions in our arteries, perhaps when a person is under chronic stress, or maybe even smoking or drinking too much. Unsurprisingly, they found high levels of free radicals and inflammation in the pot.
But repeating the experiment in the presence of oxytocin produced some quite remarkable results. Both free radicals and inflammation were substantially reduced. Free radicals were reduced by 24 percent and inflammation by 26 percent.
Stop for a moment and think of what this means. When you bond with someone, like when you're in love, for instance, you're producing oxytocin, and it is reducing your risk of heart disease. You might instead receive the benefits by chatting happily with friends. But you'll also get the same benefit when you show kindness to someone, especially if it's face to face and produces a smile.
So next time you hold that door for someone, or carry that shopping bag, be sure to smile. Even if your act of kindness only lasts a few seconds, it might be doing some good for both of your hearts. And what if you made kindness a regular thing?
The repetition of kind acts might have a cumulative effect on oxytocin production levels, at least if research on hugs is anything to go by. Oxytocin increase is a side effect of hugging. It's actually been called the "cuddle chemical." In one piece of research involving 59 women and performed at the University of North Carolina at Chapel Hill, those women who reported the most amounts of hugs with their partner had the highest levels of oxytocin. They also had the lowest blood pressure.
I guess you could say that "a hug a day keeps the cardiologist away."
Of course, these effects are no excuse for eating a two-pound steak dinner, washing it down with a bucket of ice cream, then giving out a few hugs as some sort of antidote.
I'm sure almost everyone will know someone who is a really kind person who has had heart trouble. There are many different reasons for heart conditions.
But it might just be that kindness is able to reduce the risk a little.
David R. Hamilton Ph.D.
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