Nivkara Hair Journal

Reetha for Hair: Benefits, How to Use & Reetha vs Shikakai

How soapnut cleans hair, what the research shows, how to make reetha water at home, and how it compares with shikakai and amla.

By Team Nivkara · 11 min read · Sources: 7 published studies and reviews

Before bottled shampoo, many Indian homes washed hair with a few soapnuts boiled in water. The brown, wrinkled fruit made a soft foam that cleaned hair without soap. That fruit is reetha, and it is now back in ingredient lists of "natural" and "herbal" shampoos.

So how does reetha actually work, what does research say about it, and is it better as a home remedy or in a shampoo? Let's go through it.

What Is Reetha?

Reetha, also spelt ritha or aritha, is the fruit of the soapnut tree, Sapindus mukorossi. The tree grows in the foothills of the Himalayas and other parts of India and East Asia. Its fruit is a small round berry. When dried, the outer shell (pericarp) turns golden brown and wrinkled, with a hard black seed inside.

The shell is the useful part. It contains saponins, natural compounds that make foam when shaken in water. That is where the English name "soapnut" comes from. Reetha has traditionally been used to wash hair, clothes and even jewellery.

Reetha in Indian Languages

How Reetha Cleans Hair

Saponins have one end that likes water and one end that likes oil. When you mix reetha with water, they gather at the surface and lower the water's surface tension. That lets water wrap around sebum, sweat and dirt and rinse it away. It is the same basic job that synthetic surfactants in shampoo do.

Lab tests confirm this. Saponin extracted from Sapindus mukorossi cut the tension between oil and water by about 93% at a concentration of just 0.2%.^[1] Plant saponins do tend to foam less than sodium lauryl sulphate (SLS). In one test, a plant saponin extract produced about 37% of the foam of the same strength of SLS.^[2]

Benefits of Reetha for Hair

1. Gentle, natural cleansing

Reetha removes oil and dirt from the scalp and hair. Because it foams less and is usually used diluted, many people find it less stripping than harsh soaps. It is a good fit for an oily scalp or for washing out hair oil.

2. Antimicrobial activity in the lab

A purified saponin fraction from reetha stopped the growth of Cutibacterium acnes (acne bacteria) at very low concentrations in lab tests, about 33 times more strongly than the crude extract.^[3] Researchers suggested it as a cosmetic ingredient for this reason. This was a lab study, not a scalp trial.

3. May support a balanced scalp

A 2024 study analysed 198 scalp samples from people using a fermented reetha shell filtrate for 28 days. It found shifts toward bacterial patterns linked with a healthy scalp and fewer fungal pathways.^[4] It is early research, and the study did not report changes in dandruff, itch or oiliness.

4. Good for washing out hair oil

If you oil your hair before washing, you need a cleanser that removes the oil without leaving hair squeaky and rough. Reetha does this well, especially when combined with a mild conditioner afterwards.

Also read: A Better Pre-Wash Hair Oiling Ritual: How to Use Hair Oil Without Overdoing It

5. Traditional use for a refreshed scalp

In Ayurvedic and folk practice, reetha is used for an oily, itchy or heavy-feeling scalp, often with shikakai and amla. This is traditional use, and the clinical evidence is limited.

What Reetha Cannot Do

• It does not regrow hair. There are no studies showing reetha stops hair fall from the root or grows new hair.
• It is not a proven dandruff treatment. The antimicrobial results are from the lab. For stubborn dandruff, see a dermatologist.
• It does not condition. Reetha cleans. Rough or dry hair still needs a conditioner or oil.
• It is not pH-balanced by default. Home-made reetha water varies batch to batch. Shampoo pH matters for hair: alkaline products increase friction and frizz.^[5]

Also read: When Hair Fall Needs a Dermatologist: Red Flags Every Routine Should Respect

How to Make Reetha Water at Home

Soak, boil, whisk, strain. Home-made reetha water keeps for 2–3 days in the fridge.

1. Break 8–10 reetha shells. Remove the black seeds. Only the shell has saponins.
2. Soak overnight. Put the shells in 2 cups (about 500 ml) of water and leave for 8–10 hours.
3. Boil for 10–15 minutes. Use the same water. It will turn light brown.
4. Cool and squeeze. Mash the softened shells with your hand or a whisk until foam forms.
5. Strain. Pour through a fine strainer or cloth into a clean bottle.
6. Store in the fridge. Use within 2–3 days. Throw it away if it smells sour.

Tip: add 3–4 shikakai pods and a few dried amla pieces while soaking for the traditional "reetha-shikakai-amla" wash.

How to Use Reetha for Hair

1. Wet your hair fully with lukewarm water.
2. Apply reetha water to the scalp in sections, about half a cup for medium-length hair. Keep your eyes closed or tilt your head back.
3. Massage gently for 2–3 minutes with your fingertips. The lather will be light.
4. Rinse well. Reetha residue can feel sticky if not rinsed out fully.
5. Condition the lengths. Use a conditioner or a few drops of oil on the ends.

How often? 2–3 times a week is enough for most people. If your hair feels dry, use it less or mix it with shikakai.

Reetha vs Shikakai vs Amla

Left to right: reetha, shikakai, amla.

Which one should you choose? Pick reetha if your scalp gets oily fast or you oil your hair often. Pick shikakai if your scalp is dry. Add amla if your lengths feel rough. Most traditional recipes use all three together.

Reetha Powder vs Reetha Water vs Reetha Shampoo

Home reetha is cheap and simple. A well-made reetha shampoo gives the same cleansing idea in a form you can use daily without the prep.

Nivkara Reetha Scalp Detox Shampoo

Made with reetha-infused water, plus salicylic acid to help lift buildup and loosen visible flakes, rosemary extract to refresh the scalp, and sodium gluconate to help rinse away hard-water mineral residue.

Shop the shampoo

Side Effects and Precautions

• Eyes: saponins sting. Keep reetha away from your eyes and rinse with plenty of water if it gets in.
• Dryness: using it every day, or too strong, can leave hair dry and rough. Condition afterwards.
• Allergy: rare, but reported. A chemical worker who handled soapnut extract for years developed an allergy to it.^[7] Do a patch test behind the ear 24 hours before first use.
• Broken skin: do not use on cuts, wounds or an irritated scalp.
• Children: be extra careful around eyes. Ask a doctor before using any new product on babies.
• Do not swallow reetha water or powder.

Conclusion

Reetha is a real, plant-based cleanser. Its saponins lower water's surface tension and lift oil and dirt from the scalp, which is why it has been used for hair for generations. Lab studies show antimicrobial activity and early research suggests it may support a healthier scalp, but it is not a hair-growth or dandruff cure.

Use it 2–3 times a week, keep it out of your eyes, and always follow with a conditioner or a little oil. If you want the reetha idea without the soaking and boiling, choose a reetha shampoo with a clear ingredient list.

FAQs on Reetha for Hair

Also read: Hard Water Hair Fall: Signs, Causes & How to Protect Your Hair

References

This article is for general information and is not medical advice. Nivkara products are cosmetics and are not intended to diagnose, treat or cure any disease. Contains salicylic acid: not to be used for children under 3 years of age. For persistent dandruff, itching or hair loss, consult a qualified dermatologist.