Basil Leaf

Traditional uses include the treatment of snakebites, colds, and inflammation within nasal passages — a common effect of colds, for example.

Basil provides some macronutrients, such as calcium and vitamin K, as well as a range of antioxidants.

Sweet basil, for example, has a high concentration of the chemical agent eugenol. This gives it a clove-like scent. Lime and lemon basils have high concentrations of limonene, which give them a citrusy scent. Both eugenol and limonene have antioxidant properties.

Reducing oxidative stress
Antioxidants are essential for eliminating free radicals from the body.

Free radicals are unstable molecules that develop as a result of metabolism and other natural processes. They can also form as a result of smoking and some dietary choices.

Antioxidants are compounds that help remove these molecules from the body. If they build up instead, oxidative stress can occur, resulting in cell damage and, possibly, disease.

Scientists have linked cancer, heart disease, rheumatoid arthritis, diabetes, and other health issues to oxidative stress.

The body produces some antioxidants, but it also needs to absorb some from the diet. Among the many antioxidants in basil are anthocyanins and beta carotene.

Which foods are good sources of antioxidants? Find out here.

Supporting liver health
A 2015 study in rats concluded that antioxidants in a powdered preparation that included tulsi, or holy basil, had a positive impact on liver health. The scientists applied the powder after using a toxin to induce liver injury.

Tulsi — a plant that is very different from the basil in the average Western supermarket — plays a role in Indian traditional medicine.

Fighting cancer
A review published in 2013 looked at whether tulsi, or holy basil, could prevent cancer.

The authors concluded that the phytochemicals in holy basil may help prevent certain types of skin, liver, oral, and lung cancers.

They appeared to do this by increasing antioxidant activity, changing gene expression, triggering cell death, and slowing cell division.

However, the studies in this review were preclinical or performed in animals. Confirming the effects will require further research.

Is there a link between cancer and the diet? Find out here.

Protecting against skin aging
According to research published in 2011, sweet basil has properties that might help protect the skin from some effects of aging.

In the study, the scientists applied a basil extract to laboratory models of skin. The results suggested that including basil extracts in topical skin creams might improve skin hydration and reduce roughness and wrinkling.

While extracts of basil at certain doses may have this effect, consuming basil will not necessarily benefit the skin.

However, the antioxidants in basil and other plant-based foods may have a protective effect if a person consumes them as part of a varied diet.

Learn about foods that can help boost skin health.

Reducing high blood sugar
Some practitioners of traditional medicine commonly recommend basil to help manage blood sugar levels.

A 2019 study in rats found that an extract of sweet basil leaves helped reduce high blood sugar levels. The results also suggested that basil leaves may help treat long-term effects of high blood sugar.

If further investigations confirm these findings, basil extracts could prove useful for people with diabetes.

Which foods are good for people with diabetes? Find out here.

Supporting cardiovascular health
A 2011 review reported on findings that a sweet basil extract briefly reduced high blood pressure, possibly due to the extract’s eugenol content. Eugenol can block calcium channels in the body, lowering high blood pressure.

However, 2 minutes after the researchers used the extract, the blood pressure returned to its high levels.

In another study, 24 healthy volunteers took either a placebo or a capsule containing 300 milligrams (mg) of a dried tulsi leaf extract once a day.

After 4 weeks, those who took the tulsi extract had lower levels of cholesterol and triglycerides than those who did not. The authors concluded that the extract could help reduce some risk factors for cardiovascular disease.

Find foods that may help lower blood pressure here.

Boosting mental health
Mental stress can trigger the production of free radicals in the body.

According to a 2014 review that looked at the role of tulsi in Ayurvedic medicine, the plant contains properties that may help:

alleviate stress, anxiety, and depression
increase the ability to think and reason
prevent age-related memory loss
improve stress-related sleep and sex issues
Some studies, the authors report, produced results comparable to those of diazepam and antidepressant drugs.

However, confirming these findings will require more research. Also, consuming tulsi — in a tea, for example — is unlikely to have the same effect as receiving a dosage of an extract.

How may the diet impact depression? Learn more.

Reducing inflammation and swelling
Oxidative stress can lead to inflammation, a factor in various diseases, including cancer, type 2 diabetes, and rheumatoid arthritis.

In 2017, researchers analyzed the anti-inflammatory properties of two preparations of sweet basil essential oil.

According to their results, basil oil may help treat various diseases that involve inflammation resulting from oxidative stress.

It is not clear whether eating basil, however, could have the same effect.

Which foods may help manage inflammation? Find out here.

Combatting infection
Various practitioners of traditional medicine have used basil as an antimicrobial agent, and some scientific research supports this use.

In 2013, researchers applied sweet basil oil to various strains of Escherichia coli , or E. coli. The bacteria came from people with respiratory, abdominal, urinary, or skin infections, as well as from hospital equipment. The results showed that the oil was active against these bacteria.

The researchers concluded that certain preparations of basil oil could help treat or prevent some types of infection.