Many of us face hair fall problem every now and then. There could be many reasons for hair fall including hormonal imbalance, nutritional deficiency, genetics, some medical conditions like thyroid, chemotherapy etc, DHT (Dihydrotestosterone, mostly in cases of male pattern baldness but it can also happen in women). Talk to your doctor first when you feel that the situation is getting out of control so she maye guide you about the underlying medical condition.
You must have heard about using blend of essential oils in treating hair thinning or hair fall and other problems like alopecia areata. Alopecia areata, also known as spot baldness, is an auto-immune disease in which the immune system attacks the hair follicles, causing hair loss. There is one clinical study on treatment of alopecia areata in which active group was massaged with blend of essential oils (thyme, rosemary, lavender, and cedarwood) mixed with carrier oils (jojoba and grapeseed) into their scalp daily and 44% of them shown improvement in their condition.
Many essential oils are known for anti-inflammatory property, cleanse and stimulate hair follicle and reduce stress on the scalp so the hair follicles keep open for nourishment. Essential oils are highly concentrated and potent and should not be used directly on skin and hair. They should always be used after diluting them with other carrier oils or base oils like jojoba, coconut, sweet almond, grapeseed oil etc. Some essential oils like rosemary, sage, chamomile etc (full list here) should not be used if you are pregnant or nursing. Always do a patch test of the final blend to check any allergic reaction before using all over your scalp.
How to dilute essential oil
Generally 2% dilution rule is used to make a blend. 2% dilution means using 12 drops of essential oil in 30 ml of carrier oil. Check out this link from aromaweb for more information on how to dilute essential oil and things that needs to be taken care of while making the blend. You can also refer to below chart from learningabouteos.com.