Your feelings, and the way you interact with others, impact on your overall health in some surprising ways.

So you know that getting stressed can make you cry, and you might even have heard that being happy reduces your risk of catching any cold bugs that are going around but they aren’t the only ways your emotions and your body interact. Here are 12 surprising ways your feelings can impact your health.

1. Expressing love can help to lower your cholesterol

When Professor Kory Floyd from Arizona State University asked a group of people with high cholesterol to write about their loved ones three times a week, they ended up with lower cholesterol levels than the group not involved in writing the love notes.

“We aren’t completely sure why, but one reason could be that cholesterol is elevated by a class of stress hormones called glucocorticoids, and behaviours such as affection have stress-alleviating effects that include the reduction of these,” he says.

2. Being kind protects you against atherosclerosis

Being angry seems to speed up the rate at which your arteries harden, but doing nice things for people might lower your risk of the problem. “Kindness releases the hormone oxytocin and in studies this has been shown to reduce the release of inflammatory chemicals linked to artery hardening,” says David Hamilton, author of Why Kindness is Good For You (Hay House, $26.95).

Hamilton says you’ll get the best oxytocin release from acts of kindness that see you getting eye contact and a smile from the recipient so do something nice for someone today!

3. Stress worsens PMS

This applies specifically to stress experienced in the second half of your menstrual cycle, say researchers at the University at Buffalo in the US. The theory is that getting all worked up increases your production of chemicals called prostaglandins that are linked to PMS.

Other research has also shown that women with high levels of stress are twice as likely to suffer period pain than those with low levels.

4. Getting angry fights stress

Next time life is getting on top of you, have a good yell. According to research from Dr Neus Herrero at the University of Valencia, getting angry sends a surge of blood to the left hemisphere of the brain and that’s the side that produces happy emotions which then relax you.

Another study in the US has found that people who make angry faces in response to stress get lower spikes in blood pressure and stress hormones than those reacting in other ways. “It’s possible that if you’re in a situation that is maddening and in which anger or indignation are justifiable responses, anger is not bad for you,” says the trial’s author Jennifer Lerner.

Just remember, though, that screaming into a pillow is less likely to end in a row than if you were to scream at your boss.

5. But too much anger can upset your gums

So while appropriate levels of anger are good, raging all the time is associated with a heap of health issues, the most perplexing of which must be gum disease.

Experts at Harvard University found that men who were regularly angry were 72 percent more likely to have gum disease than calmer men. Spikes in the insulin released during rage were thought to be the likely cause as high insulin levels are strongly linked to gum issues.

“If you want to try and control your anger, it’s good to start to recognise the clues you give off before you’re about to lose control, like tapping your finger on the table,” says Lee Town from the Anger Management Institute of Australia. “This gives you an opportunity to remove yourself from the situation while you’re still calm.”

6. Being cynical could stop your medicine working

Research from Oxford University saw doctors administering pain to people in four different situations without a painkiller, after secretly giving them a painkiller, after telling participants they were receiving painkillers, and giving them a painkiller but telling them the opposite.

The study revealed that when the participants believed they’d had no pain relief, their level of pain was practically the same as if they hadn’t taken anything. The drug simply had no effect. Yet when they knew they were getting medication, pain levels fell by almost half. If you want medicine to work, you need to believe it will.