Spearmint tea is a medicinal beverage made from the leaves and flowering tops of the spearmint plant. Unlike teas made from the camellia sinensis tea plant – such as green tea – spearmint tea does not contain any caffeine. Although no clinical studies have been performed on the interaction between spearmint tea and caffeine, moderate dosages of both substances are not likely to cause a negative reaction.
According to a study published in a 2010 issue of “Phytotherapy Research,” spearmint tea may have a significant anti-androgen effect on individuals suffering from polycystic ovarian syndrome. One of the side effects of this condition is hirsutism, a cosmetic and psychological problem caused by increased levels of androgen and other male sex hormones in women. Like peppermint and other plants of the mint family, spearmint may also alleviate digestive discomfort, although this effect has not been clinically studied. Aside from its medicinal uses, spearmint tea also is consumed for its minty flavor and aroma.
Spearmint and Caffeine
Both spearmint and caffeine have a stimulating effect on the nervous system. According to a report published on the FDA website, spearmint can have a beneficial effect on energy circulation. Caffeine has a much more pronounced effect on the central and sympathetic nervous systems, and can stimulate the production of stress hormones after consuming 100 to 200 milligrams of caffeine. One of the reasons why caffeine is considered so potent is its inhibitive effects on fatigue receptors called adenosine. As a result of caffeine in the brain, these receptors are prevented from causing symptoms of drowsiness and sleepiness, resulting in an overall delay in fatigue sensations.
There are no known interactions between spearmint tea and the caffeine found in beverages and foods. According to the “The New York Times” Health Guide, both caffeine and spearmint may cause a worsening of heartburn and other gastroesophageal reflux disease symptoms. Like peppermint tea, spearmint can be added to green or black teas to form an aromatic caffeinated beverage. Mild to moderate intake of spearmint tea and caffeine is not likely to cause any adverse effects or interactions.
The BreastCancer.org website includes spearmint among its list of estrogen-containing herbs. Individuals suffering from hormone imbalance, estrogen dominance, breast or other cancers should avoid taking spearmint without a doctor’s approval. Although caffeine is generally considered safe when kept to daily doses of 300 milligrams, some individuals may experience unpleasant effects such as upset stomach, irritability, anxiousness, muscle tremors and accelerated heart rate after consuming caffeine.