Health Benefits of Holy Basil

Reviewed by Dany Paul Baby, MD on November 26, 2022

Nutritional Info

from the WebMD Ingredients Guide
Serving Size 1 Tablespoon
Calories 1
% Daily Value*
Total Fat 0 g
Saturated Fat 0 g
Trans Fat 0 g
Cholesterol 0 mg
Sodium 0 mg
Potassium 0 mg
Total Carbohydrate 0 g
Dietary Fiber 0 g
Sugar 0 g
Protein 0 g

*Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.

  • Vitamin C 0%
  • Iron 0%
  • Vitamin B6 0%
  • Magnesium 0%
  • Calcium 0%
  • Vitamin D 0%
  • Cobalamin 0%
  • Vitamin A 3%

Holy basil, also known as tulsi, is an herb originally grown in the tropical climates of India and nearby countries. The scientific name is Ocimum sanctum or Ocimum tenuiflorum L. 

In addition to being an herbal supplement, the holy basil tulsi plant is an important part of Hindu culture. Those in the largest Hindu sect, Vaishnavism, use tulsi for worship, prayer, and other spiritual rituals.

In India, tulsi is an important antioxidant in a holistic medicinal practice. This form of traditional medicine is called Ayurveda, which considers health problems to be imbalances within a person’s mind, body, and spirit.

Health Benefits

Holy basil has a calming effect that can help battle stress and give you a boost of energy, and it offers some antimicrobial benefits, too, which help kill bacterias. Here are a few of the health benefits of holy basil:

Improves Asthma Symptoms

Early studies indicate that holy basil may reduce airway swelling in people with asthma. However, one of these studies relied on animals, and though two clinical trials did show improvement among a group of people taking holy basil to help with swollen airways, the studies didn’t include a group who did not take holy basil, for the sake of comparison. While helping with breathing and reducing irritation of airways is a common use of holy basil, more research is needed to be sure these effects are confirmed.

Helps Symptoms of Type II Diabetes

Animal and human studies have suggested that holy basil can lower both blood glucose and cholesterol levels. One study found that rats who were given holy basil saw a 26% decrease in blood sugar after 30 days. Studies with human participants show similarly promising results, suggesting that holy basil may be helpful in easing symptoms for people with type 2 diabetes.

This can make diabetes easier for you to manage.

Kills Bacteria

Holy basil is well-loved for its antimicrobial properties, which help kill bacteria. In an early study, holy basil oil completely stopped the growth of the bacterias MRSA and E. Coli. It partially affected P. aeruginosa. However, more study is needed to find out how this treatment would work in humans. 

Improves Immune System Function

A traditional Ayurveda belief is that holy basil improves overall immunity when taken on an empty stomach.. Researchers verified this idea in a small study. The results showed improved immune system benchmarks, including an increase in the levels of T cells. T cells are a type of blood cell that fights infections.

May Reduce Damage from Many Types of Stress

Holy basil is an adaptogen, a substance that guards against physical and mental stress . Studies suggest that this adaptogen can protect you from the effects of:

  • Certain industrial chemicals
  • Heavy metals
  • Physical strain
  • Extremely cold temperatures
  • Poor diet
  • Low physical activity
  •  Depression

However, more study is needed to verify these results and determine how best people might benefit from holy basil.

Health Risks

Preliminary studies show that taking holy basil regularly is safe. However, ask your  doctor before adding tulsi to your routine, because more research is needed to determine its potential side effects.

Amounts and Dosage

Holy basil comes in many forms including:

  • Teas
  • Capsules
  • Tinctures
  • Extracts
  • Powders

There is no official dosage information for holy basil. It’s important to remember that natural supplements aren’t well-regulated, so pay close attention to the label. Ask your doctor about dosage information and read the instructions before taking a supplement.

Show Sources


Berkeley Herbal Center: “How to Use Tulsi Holy Basil in Herbal Medicine Making.”

Evidence-Based Complementary and Alternative Medicine: “The Clinical Efficacy and Safety of Tulsi in Humans: A Systematic Review of the Literature.”

Frontiers in Microbiology: "Antimicrobial Activity of Tulsi (Ocimum tenuiflorum) Essential Oil and Their Major Constituents against Three Species of Bacteria."

International Journal of Clinical Pharmacology and Therapeutics: “Randomized placebo-controlled, single blind trial of holy basil leaves in patients with noninsulin-dependent diabetes mellitus.”

Journal of Ayurveda and Integrative Medicine: "Tulsi - Ocimum sanctum: A herb for all reasons."

Journal of Ethnopharmacology: “Ethanolic extract of Ocimum sanctum leaves partially attenuates streptozotocin-induced alterations in glycogen content and carbohydrate metabolism in rats.”

Kaiser Permanente: "Holy Basil."

National Ayurvedic Medical Association: "History of Ayurveda."

National Cancer Institute: "T cell."

United States Department of Agriculture Natural Resources Conservation Service: "Classification for Kingdom Plantae Down to Species Ocimumtenuiflorum L."

University of Minnesota Taking Charge of Your Health & Wellbeing: "What is the Philosophy of Ayurvedic Medicine?"

© 2022 WebMD, LLC. All rights reserved. View privacy policy and trust info