Lemon balm (Melissa officinalis), a member of the mint family, is considered a calming herb. It was used as far back as the Middle Ages to reduce stress and anxiety, promote sleep, improve appetite, and ease pain and discomfort from indigestion (including gas and bloating, as well as colic). Even before the Middle Ages, lemon balm was steeped in wine to lift the spirits, help heal wounds, and treat venomous insect bites and stings. Today, lemon balm is often combined with other calming, soothing herbs, such as valerian, chamomile, and hops, to promote relaxation. It is also used in creams to treat cold sores (oral herpes).

A 2004 studyTrusted Source found that taking lemon balm eased the negative mood effects of laboratory-induced psychological stress. Participants who took lemon balm self-reported an increased sense of calmness and reduced feelings of alertness.

Although this was a double-blind, placebo-controlled study, it had a small sample size of 18 people. Further research is needed to elaborate on these findings.

Lemon balm may also be used to help reduce symptoms of anxiety, such as nervousness and excitability.

Research published in 2014 examined the mood and cognitive effects of foods containing lemon balm. The supplement was mixed into a beverage and into yogurt along with either natural or artificial sweeteners. Participants in both groups reported positive effects on various aspects of mood, including reduced levels of anxiety.

Although this is promising, more research is needed to truly determine its efficacy.

The same 2014 study also looked at the effects of lemon balm in improving cognitive function.

Participants were asked to do cognitive tasks involving memory, mathematics, and concentration. The results of these computerized tasks suggest that participants who ingested lemon balm performed better than those who didn’t.

Although these participants did experience an increase in levels of alertness and performance, it’s still possible for fatigue to set in over time. Combining lemon balm with food also affects its absorption rate, which may have had an impact on its efficacy. Additional research is needed

Combining lemon balm with valerian may help relieve restlessness and sleep disorders such as insomnia.

Researchers in one 2006 study found that children who took a combined dose experienced a 70 to 80 percent improvement in symptoms. Both the researchers and parents regarded lemon balm as being a good or very good treatment. Still, more research is needed to validate these findings.

If you experience frequent abdominal pain and discomfort, lemon balm may have a positive effect on your digestion.

A small study from 2010Trusted Source assessed the effects of a cold dessert containing lemon balm on functional dyspepsia. Participants ate a sorbet, with or without the herb, after a meal. Although both types of desserts lessened the symptoms and their intensity, the dessert containing lemon balm intensified this effect. More research is needed.

Given its potential impact on your digestive system, lemon balm may also help relieve feelings of nausea.

A 2005 review assessing the results of several studies on lemon balm found the herb to be useful in treating gastrointestinal symptoms such as this. Although this is a promising development, it’s important to recognize the study limitations.

Many of the studies looked at lemon balm used in conjunction with other herbs. Further research is needed to determine the efficacy of lemon balm when used alone.

There’s also research to suggest that lemon balm can be used to relieve menstrual cramps and premenstrual syndrome (PMS).

A 2015 studyTrusted Source researched the effect of lemon balm in reducing the intensity of cramps in 100 high school girls. The girls took either a lemon balm essence or a placebo for three consecutive menstrual cycles. The intensity of PMS symptoms was analyzed before and one, two, and three months after the trial. The group who took the lemon balm reported a significant reduction in symptoms. Further research is needed to confirm these findings.

Lemon balm may also be useful in treating headaches, especially if they’re happening as a result of stress. Its relaxing properties can help you to unwind, release tension, and relax your muscles. It’s also though that ingesting the herb can help to open up and relax tight blood vessels, which can contribute to headaches.