This Valentine's Day, when you look over at your romantic partner, you'll likely reflect on all the wonderful ways they've impacted your life. And while we know that love has far-reaching benefits for our mental health, we rarely stop to reflect on its impacts on our physical health.

It turns out, the heart isn't a symbol of love for nothing. Feelings and expressions of love carry specific benefits to this critical organ.

Love letters lower cholesterol

Yes, you read that right: Writing love letters actually lowers your cholesterol. In a study by Human Communication Research, one group of subjects were asked to write letters about random mundane topics, while another group was asked to write love letters to their romantic partners.

The latter group showed a significantly reduced level of total cholesterol. This effect may be caused by chemicals in the brain that release when we think about those we love. Love does not just feel good, it's actually good for us.

Romance gets your heart rate up

Have you ever felt your heart race at the sight of your romantic partner? Well, it turns out that's good for you! Your increased heart rate due to "butterflies" is not that different than the increased heart rate produced by aerobic exercise. Getting your heart rate up for limited periods of time usually helps strengthen your cardiovascular system.

Romantic partners lower blood pressure

According to a study in the Journal Psychosomatic Medicine, spending time with those you love provides a larger dip in blood pressure than spending time with strangers. While some people can cause your heart to race (in a bad way) and make it feel difficult to breathe, spending time with romantic partners can release cortisol, relax your body, and actually lower your blood pressure. Often, the more time you spend with your romantic partner, the better.

Holding hands reduces stress

To anyone who has ever held the hand of someone they love, it's no surprise a study published in Psychological Science found that doing so can relieve stress and calm your nerves. It is well known that regular human-to-human contact is good for psychological well-being. Contact from a loved one, though, seems to be particularly potent.

Dangers of a broken heart

While there are many medical upsides to love, there are also a few downs. "Suffering from a broken heart" is more than just an expression. There is actually something (more commonly seen in women than in men) called Broken Heart Syndrome which is characterized by sudden enlargement and ineffective pumping due to prolonged emotional distress. Usually, the condition takes care of itself for -- as with all love-based wounds -- time seems to be the only cure.