What is Spearmint?

Spearmint is the common garden mint. Its leaves flavour tea, sauces, sweets and chewing gum. The plant is Mentha spicata, also listed in older books as Mentha viridis.

As a remedy, it was used for upset stomach, wind and nausea. Newer interest has moved elsewhere. Spearmint tea has been tested for hormone levels in women, and spearmint extracts are sold for memory and focus.

Here is the short verdict. As a food and an everyday tea, spearmint is safe for most people. As a treatment, the human evidence is thin and comes from a handful of small studies.

Long use in folk medicine is not proof that something works. It is also not proof that it is safe. This page says plainly where the evidence runs out.

How does Spearmint work?

Most of what we know about how spearmint acts comes from the lab, not from people.

Spearmint leaves hold rosmarinic acid and other polyphenols (plant compounds that mop up damaging molecules). In test tubes these slow some inflammation signals. Whether that happens in your body at tea-sized amounts is not known.

In two small human trials, spearmint tea lowered free testosterone (a male-type hormone that women also make). How it does this is unclear. One idea, untested in people, is that it changes how the body makes or carries that hormone.

Mint oils relax smooth muscle in lab strips of gut tissue. This is shown best for peppermint, which is a different plant. It is the usual explanation for mint easing cramps, but for spearmint it stays an explanation, not a proven result.

A branded spearmint extract high in rosmarinic acid has been studied for memory. In animals it appears to shield brain cells from oxidative stress (damage from unstable molecules). The link between that lab finding and the human results is not established.

What forms does Spearmint come in?

Spearmint is sold as a food, a tea and a supplement.

- Fresh or dried leaf, for cooking and for tea. - Tea bags, plain or in blends. - Capsules or tablets of leaf extract, often standardised for rosmarinic acid.

- Essential oil, used for scent and flavour. - Toothpaste, mouthwash and chewing gum. - Flavouring in sweets and drinks.

The oil is very concentrated and is not a strong tea. Food and flavour uses have the longest safety record. Extracts are newer, and the amount per capsule varies widely by brand.

Labels should name the plant and the part used. A label that says only "mint" tells you little.

Where it comes from:

Spearmint came to North America with European settlers and spread into gardens, ditches and damp ground.

Nineteenth-century American Eclectic doctors listed it as a mild remedy. They gave warm leaf infusions for upset stomach, wind, hiccups and the nausea of fevers. It was also given to children and to people recovering from illness.

Eclectic writers rated it as gentle rather than strong. Peppermint was their choice when they wanted a sharper effect. Spearmint was often used for urinary complaints and to make other medicines taste better.

It also had a long kitchen life in sauces, jellies and cordials. Mint waters were common in home medicine chests.

These records tell you what people did and believed. They do not tell you whether it worked.

What does Spearmint help with?

• Upset stomach, bloating and wind: Folk use of mint tea for cramping and wind is old and widespread. Human trials of spearmint on its own for this are lacking. Most gut research used peppermint oil, which is a different plant with far more menthol. A warm drink can ease a full, gassy feeling by itself. That may explain part of what people notice.
• Nausea and queasiness: Tradition used mint tea for queasiness, travel sickness and fevers. The human evidence is weak, and what exists mostly covers peppermint or mixed mints. Spearmint may make you feel more comfortable. It is not a proven antiemetic (anti-sickness) treatment.
• Unwanted hair growth and high androgens in PCOS (polycystic ovary syndrome, a hormone condition): This is the best-studied use, and the studies are still small. Two short trials in women with hirsutism (unwanted coarse hair growth) found that spearmint tea twice a day lowered free testosterone. Measured hair growth barely changed over a month. These results do not show that spearmint treats PCOS. Hormone symptoms need a proper diagnosis. Talk to your doctor before adding it to prescribed care.
• Memory and attention in older adults: One branded spearmint extract, high in rosmarinic acid, has been tested for memory. A trial in adults with age-related memory complaints reported small gains in working memory over 90 days. The study was funded by the extract's maker. It has not been widely repeated by independent groups. Ordinary spearmint tea has not been shown to do this.
• Breath and mouth freshening: Spearmint flavours most gums and toothpastes, and it masks odour well. The freshening effect is real but short. It does not treat the causes of bad breath, such as gum disease, tooth decay or dry mouth. Lasting bad breath is worth a dental check.

Which foods are rich in Spearmint?

1. Fresh spearmint leaves in salads and tabbouleh
2. Spearmint tea and Moroccan-style mint tea
3. Mint sauce and mint jelly
4. Yoghurt and cucumber dishes
5. Chewing gum, mints and toothpaste
6. Mint cordials and mojitos

Practical Tips:

Spearmint is a food first and a remedy second.

Eating it in meals is the oldest and best-tested use. Cooking amounts are far below anything used in studies.

Strong daily tea sits somewhere between food and supplement. That is where the hormone question comes in, so it is worth knowing about.

What are the side effects of Spearmint?

• Heartburn or reflux getting worse
• Irritation of the mouth or lips from strong mint flavours
• Rash or itching in people sensitive to mint-family plants
• Nausea from very strong tea or from oils
• Headache, reported rarely
• Lower testosterone with regular daily tea, which matters for some people

Good to know:

Side effects are uncommon and usually mild at food and tea amounts.

The most common complaint is reflux (stomach acid rising into the throat). Mint can loosen the valve at the top of the stomach. If mint tea gives you heartburn, that is a reason to stop.

Serious harm is tied to the essential oil, not the leaf. Swallowing mint oils can poison, and the risk is highest in babies and young children.

The hormone effect is not a side effect for everyone, but it is real. It is a reason for some people to skip daily tea.

How much Spearmint should you take?

• Recommended daily: These are the amounts labels and studies carry, not advice for you. Tea labels usually suggest one to two cups a day. A cup is made from about 1 to 2 grams of dried leaf. Extract capsules often carry 450 to 900 mg a day on the label. The hirsutism trials used one cup of tea twice daily. That was a study amount in a monitored setting. Cooking amounts are not measured and do not need to be. Spearmint essential oil is not something to swallow at home.
• Best time of day: Timing matters little. Tea after meals suits the digestive use, since that is when bloating tends to hit. The hormone trials split the tea across the day, morning and evening. Mint is not a stimulant, so an evening cup is fine for most people.
• With or without food: Either works. Tea after a meal is the usual choice for digestion. Capsules sit better with food for some people. If you take iron tablets, tea is best kept a couple of hours apart from them.
• Time to effect: Any easing of a full, gassy stomach is usually felt within the hour, if it comes at all. Hormone changes in the trials took weeks. They were picked up by blood tests, not by how the women looked or felt. Hair growth did not visibly change in a month. The memory extract trial ran 90 days before reporting small gains. For many people, spearmint will do nothing measurable. That is a fair outcome to expect.
• How long to take it: As a food or everyday tea, spearmint has no set time limit. The hormone trials ran five days and 30 days. The memory extract trial ran 90 days. Longer use has not been studied properly. A sensible habit is to review after about a month. If nothing has shifted, stopping costs you nothing.