Holy Basil Benefits: Ayurveda Herbal Medicine

Holy basil is commonly known as Tulasi in Sanskrit or Tulsi in Hindi. It is a perennial flowering plant from the mint family called Lamiaceae. Though this plant is native to the Indian subcontinent, it grows throughout Southeast Asia.

There are several types of holy basil. It is highly revered for its medicinal uses within the Ayurvedic and Siddha medical systems and has been used for thousands of years in Ayurveda for its diverse healing properties.

The Ocimum tenuiflorum or Ocimum sanctum species consists of the following:

• Rama or Sri tulsi, which has green leaves
• Krishna or Shyama tulsi, which has purple-colored leaves

Another species of holy basil is called Ocimum gratissimum. This species or type of holy basil is also known as Vana or wild forest tulsi, which has dark green leaves.

In general, holy basil is thought to work by helping your body cope with various stressors—like emotional stress, an infection, or other medical conditions. This article will look at what the research shows about holy basil in terms of potential benefits, possible side effects, and interactions.

Mind and Body Holy Basil Benefits

Holy basil is an adaptogen and contains several nutrients, including vitamins A and C, calcium, iron, and zinc.

The way in which holy basil works isn’t exactly clear. Though more research is necessary, some of holy basil’s effects may involve the gamma-aminobutyric acid (GABA) pathways that naturally exist in your body.

Though GABA supplements exist, they do not readily cross the blood-brain barrier in this form. With this in mind, they’re likely not as effective as some companies would lead you to believe.

When using herbal medicine, it is important to make informed decisions. A healthcare professional, such as a registered dietitian, pharmacist, or healthcare provider can help review and individualize your supplement use to be sure it is safe and supports your health needs.

Like many herbs, people may use holy basil for various reasons. But there are several clinical trials assessing holy basil for the following potential uses. Read on for more information.

Improves Metabolic Conditions

In a systematic review, several small short-term studies suggested holy basil improved metabolic conditions including:

• Blood glucose (sugar) in diabetes
• Cholesterol in hyperlipidemia
• Blood pressure in hypertension
• Body mass index (BMI)

Metabolic conditions raise the risk of heart-related problems. More research is needed to understand how holy basil may be improving symptoms of these health conditions.

Reduces Inflammation and Improves Immunity

A systematic review linked holy basil to better lung function and relief from asthma symptoms in a small short-term study—suggesting that holy basil may have reduced inflammation (swelling) in the airways.

The small short-term clinical trials suggested holy basil had some effect on the immune system (the body’s defense system)—especially against viral infections.

Given the studies were small and short-term, additional research with more participants is needed to confirm the effects holy basil has on inflammation and immunity.

Improves Stress and Brain Health

In small, short-term studies (two weeks), holy basil did slightly better than a placebo (a substance with no medication) in improving attention and memory.

As for mood and stress, the results were mixed. This may have something to do with the various holy basil “dosage forms” studied—such as capsules versus powder. Each study also examined different parts of the holy basil plant.

Larger, long-term studies are needed to understand how holy basil impacts symptoms related to brain health and stress.

Improves Sleep

An eight-week study including 100 participants found taking holy basil extract may improve subjective measures of sleep quality. However, sleep quality was measured using a wrist-worn sleep tracker. The study authors noted that further research using gold-standard objective sleep measures will be required to substantiate the sleep-related findings.

What Are the Side Effects of Holy Basil?

Similar to many medications, side effects are possible when taking holy basil.

Common Side Effects

Holy basil seems to be safe for most people but can have side effects, such as nausea or diarrhea. Holy basil might also worsen hypothyroidism by decreasing levels of the thyroid hormone thyroxine. It might also increase the risk of bleeding by slowing down blood clotting.

Severe Side Effects

Several clinical trials suggest that holy basil doesn’t cause serious side effects. But a severe allergic reaction is a possible serious side effect if you're allergic or sensitive to any members of the Lamiaceae (mint) plant family. Symptoms may include breathing difficulties, itchiness, and rash.

If you’re having a severe allergic reaction or if any of your symptoms feel life-threatening, call 911 and get medical help right away.

Use Holy Basil With Caution

Dietary supplements are not regulated like drugs in the United States, meaning the Food and Drug Administration (FDA) does not approve them for safety and effectiveness before products are marketed.

Choose a supplement tested by a trusted third party, such as USP, ConsumerLab, or NSF, when possible. However, even if supplements are third-party tested, that doesn’t mean they are necessarily safe for all or effective in general.

The safety of taking holy basil for longer than eight weeks has not been studied, and holy basil may pose risks in the following situations:

• Severe allergic reaction: Avoid this herb if you have a severe allergic reaction to holy basil or any of its components (parts or ingredients).
• Pregnancy or breastfeeding: Studies with holy basil may exclude pregnant or breastfeeding people. As a result, information on the safety and effectiveness of holy basil while pregnant or breastfeeding remains limited. Data on the safety and effects of holy basil in nursing infants is also limited. For this reason, take holy basil with caution. Your healthcare provider can help you weigh the benefits and risks of taking holy basil during pregnancy or breastfeeding.
• Children: A 2017 systematic review didn’t include studies with children. There is limited information about the effects and safety of holy basil in children. Reach out to your child’s healthcare provider (pediatrician) to discuss the benefits and risks of holy basil.
• Older adults: Older adults did participate in some studies included in a systematic review of holy basil. Though holy basil didn’t appear to be linked to severe side effects, these studies were small and short-term. Older adults may be more sensitive to side effects from medications.

Talk to your healthcare provider about any supplements you plan to take. They can inform you of any potential interactions with other supplements or medications you take.

Dosage: How Much Holy Basil Should I Take?

Though there are several small short-term studies on holy basil, larger, well-designed studies are necessary. For this reason, there are no set guidelines on the appropriate dosage to take for any condition.

Supplements of holy basil extract are available in pill or capsule form. Dosages used in studies varied from 500 milligrams (mg) to 3,000 mg per day.

Holy basil can also be used in tea by using the leaves, flowers, or dried leaf powder, or can be freshly brewed by placing 2–3 teaspoons of holy basil in a cup of boiling water and letting it steep for 5–6 minutes.

In addition to the over-the-counter (OTC) supplement form, holy basil is also available from natural sources. Holy basil is also a culinary (cooking) herb.

Before taking holy basil, talk with a healthcare provider and follow product label instructions to ensure the supplement and dosage are safe for your individual needs.

What Happens if I Take Too Much Holy Basil?

There is little information about holy basil toxicity and overdoses in humans. But there were negative effects on sperm count and sex hormones in male rabbits with high doses of holy basil leaves at 2 grams for 30 days.

If you think you’re experiencing an overdose or life-threatening symptoms, get medical help immediately.

Medication Interactions

Use caution when taking holy basil with the following:

• Blood pressure medications: Holy basil has demonstrated blood pressure-lowering effects. This may have additive effects with antihypertensives—like Microzide (hydrochlorothiazide). If your blood pressure is too low, you may experience dizziness and feel faint.
• Blood thinners: In animal studies, holy basil slowed blood clotting time. Because your body will take longer to stop the bleeding, you may also bleed longer. This means that holy basil may interact with other blood thinners, such as Coumadin (warfarin).
  
• Cholesterol medications: Holy basil may have cholesterol-lowering effects. This may have additive effects or increase the side effects of your cholesterol-lowering medications, such as Lipitor (atorvastatin).
• Diabetes medications: Holy basil may have blood sugar-lowering effects. This may have additive effects with your diabetes medications. If your blood sugar is too low, symptoms may include excessive tiredness, confusion, and sweating.
• Immune support medications: Since holy basil may have immune system effects, use caution with other similar medications, such as Humira (adalimumab). Humira is for autoimmune conditions, where your body attacks parts of your body by mistake.
• Relaxants: After taking holy basil, you might experience a calming effect. This might increase the side effects of other medications that have similar effects, such as sleep-inducing medications like Ambien (zolpidem).

Carefully read a supplement’s ingredient list and nutrition facts panel to understand which ingredients and how much of each ingredient is included. Before taking holy basil, review the supplement label with your healthcare provider to discuss any potential interactions.

How to Store Holy Basil

Storage instructions vary for different products. Carefully read the directions and packaging label on the container. Keep your medications tightly closed and out of the reach of children and pets, ideally locked in a cabinet or closet. Try to store your medicines in a cool and dry place.

Discard after one year or as indicated on the packaging. Avoid pouring unused and expired products down the drain or in the toilet. Visit the FDA’s website to know where and how to discard all unused and expired medications. You can also find disposal boxes in your area.

Ask your healthcare provider if you have any questions about the best ways to dispose of your medications or supplements.

If you plan to travel with holy basil, review the regulations of your destination. Checking with the U.S. embassy or consulate might be a helpful resource.

Sources of Holy Basil and What to Look For

In addition to the over-the-counter (OTC) supplement form, holy basil is also available from natural sources and as a culinary (cooking) herb.

Food Sources of Holy Basil

Holy basil is naturally available as a plant from the mint family. The leaves and plant parts may be used in cooking or to make tea.

In general, dietary changes may interact with your medications or affect your medical conditions. For this reason, talk with your healthcare provider to safely make any dietary changes.

Holy Basil Supplements

Holy basil is available in many dosage forms, including capsules and tablets. If you have difficulties swallowing pills, holy basil is available in other dosage forms including:

• Liquid
• Powder
• Tea bags

Holy basil is also available as vegetarian and vegan products. The specific product you choose will depend on your preference and the benefits you'd like to achieve. Each product may work differently depending on the form, so following the directions is essential.

Summary

Holy basil is a perennial flowering plant from the mint family. Though it’s also a common cooking herb, it may also have some potential medicinal effects. For example, it may reduce blood pressure, blood sugar, and cholesterol. What’s more, it might have some effects on memory and immune support.

Although holy basil is available as a cooking herb and an over-the-counter (OTC) supplement, side effects and drug interactions are possible. More research is needed to assess holy basil’s effectiveness and safety. Before using holy basil, talk with your pharmacist or healthcare provider to help you safely achieve your health goals.