Your boss just left you a ranting voicemail for the second time this week. Your neighbor seems completely oblivious to the fact that his unkempt lawn and growing pile of trash is affecting everyone else. And then some jerk cuts you off in traffic so you have to swerve dangerously to avoid an accident! Can you feel your blood pressure rising?

In an ideal world, any insult or offense would immediately be followed by a heartfelt apology, along with the promise never to do it again. In reality, many conflicts go unresolved, and that can leave you hanging on to a lot of resentment and frustration.

More: 10 warning signs of burnout & excessive stress

If you need a motivator to let go of your irritation with a thoughtless coworker or anger at an unreliable ex, recent scientific research might help.

Here are three great reasons to start moving on:

Forgiveness reduces stress
In one clinical trial, people who actively practiced forgiveness had measurably lower levels of stress hormones. In contrast, just seeing a picture of someone they held a grudge against caused other subjects' stress markers to skyrocket! We're not just talking a speedier heart rate here, either—a wide range of blood tests that indicate stress were all affected. The takeaway? Forgiving others means you feel less stressed, and that can reduce your risk for everything from heart disease to type 2 diabetes.

More: 6 weird signs that you're way too stressed out

Forgiveness helps you lose weight
There are multiple hormones like cortisol and ghrelin that help regulate your appetite and weight, and research shows they're directly impacted by your mindset. The stress of being angry or depressed actually makes you feel hungrier. It also means your body is less likely to burn fat. Want to shed some pounds? Letting go of resentment from your past is a great place to start!

More: 6 hormones essential for fat loss

Forgiveness makes you live longer
Science proves that people who are forgiving can live longer and age more slowly. In fact, people who rated themselves as highly forgiving of both others and themselves had fewer health conditions and a longer lifespan. (It's worth noting that the older people got, the more positive and powerful the effects of their willingness to forgive. Forgiveness is a habit it pays to keep for life...)

More: Live almost 4 years longer with this diet tweak

Holding on to bitterness or shame can actually take years off your life... ouch. On the bright side, studies show that people who practice forgiveness live longer, healthier, happier lives. We all know the phrase "forgive and forget." But it turns out a more appropriate version might be "forgive and live"!

This article originally appeared on RodaleWellness.com.