It is recommended that rosemary oil is applied to the scalp and hair daily to see the best results.
“Everyone can use rosemary oil, but you might need to modify how often you use it depending on your hair type,” suggests Dr. Khetarpal. “Some people might be able to use it daily. Others may see that one or twice a week works best.”
"Rosemary essential oil can help stimulate healthy, thick hair," affirms Dr. Graf. "The oil can speed up the process of cell turnover and growth, which can work as a natural remedy to grow thicker hair. Since it is an anti-inflammatory, it is used for (preventing hair loss), as well as regrowth."
Why? Rosemary oil contains properties that can help stimulate blood circulation to the scalp, which can promote hair growth. However, if it is used excessively or in its purest form, it can cause scalp irritation and even allergic reactions, leading to hair loss.
The participants of the study showed a significant increase in hair count after 6 months of using rosemary oil. The overall result of the study provided evidence that rosemary oil may be effective for certain hair growth. A study from 2022 also found evidence that rosemary oil can aid in hair growth.
While rosemary oil is generally considered safe and effective for promoting hair growth, there is a possibility of increased hair shedding or temporary hair loss after discontinuing its use, particularly if it was used for an extended period.
Overall, Dr. Shende says that rosemary oil is considered safe for topical use on the hair and scalp, knowing that individual results may vary. She recommends doing a patch test before using any new essential oil or hair product to check for potential allergic reactions or sensitivities.
Leaving the hair growth oil on for a few hours can enhance its benefits. For the best results, leave the oil on for two to three hours to allow for effective nourishment. If your hair is particularly dry or damaged, consider an overnight treatment, but be sure to cover your hair to protect your pillow.
That said, there is a growing body of scientific evidence that rosemary oil is beneficial for hair growth. One study found that it's at least as effective as 2% Minoxidil for treating male pattern baldness, and is less likely to cause scalp irritation [1].
Leaving your oil on your hair for more than one day is a bad idea. Even one day is not recommended since it can cause the oil to form a layer on your scalp, clogging your pores, accumulating dandruff and attracting dirt. Apart from that, it will make your scalp constantly feel greasy and dirty.
Generally, he says, the range is somewhere between once a day and once a week. “If you have very fine or thin hair, you may need to wash more often, while those with thick or curly hair may need to wash less often,” says Dr Elizabeth Bahar Houshmand, a double board certified dermatologist and hair health expert.
Yes, you can leave rosemary oil in your hair overnight to reap the benefits while getting some well-deserved rest. However, it is important not to leave directly-applied rosemary oil on the hair overnight, as this can cause irritation. Only ever use diluted rosemary oil or products infused with rosemary oil.
The application of oil to the hair should be done atleast 30-60 minutes before shampooing to get best and effective results.
Because it's a pretty potent ingredient, for some, excess use of rosemary oil may lead to some itching and burning, says Holdsworth. “It can cause mild irritation of the scalp and should be discontinued if this is experienced,” adds Dr. Garlapati.
If using rosemary oil for hair growth, I recommend you apply it directly to the scalp and massage it in for several minutes. It should be used one to two times a day for best results. It is also worth noting that massage alone increases blood flow to the scalp and may help promote healthy hair growth.”
Conclusion. A combination of rosemary and coconut oil for hair can really help make your hair thicker and healthier. Rosemary oil nourishes your scalp, while coconut oil moisturizes your hair. This combo can make your scalp healthy, strengthen your hair, and give you the thick hair you want.
Taking large amounts of rosemary can cause vomiting, sun sensitivity, and skin redness. When applied to the skin: Rosemary oil is possibly safe for most people. It might cause allergic reactions in some people. When inhaled: Rosemary is possibly safe for most people when used as aromatherapy.
It's best to use it daily or at least three to four times a week to see noticeable improvements. Dilution: Rosemary oil should always be diluted with a carrier oil, such as coconut oil or jojoba oil, before application. The recommended dilution ratio is usually 5 drops of rosemary oil per 10ml of carrier oil.
"There are no great studies to know exactly how long it takes improvement, but usually it will probably take 4-6 weeks to help with hydrating the scalp, and about three months to see results, as it takes time to have hair grow out," says Dr. Kobets.