Does the “Greenhouse Effect” Really Increase Hair Growth?


By Chinwe of Hair and Health

What is the “Greenhouse Effect” (GHE) Method?  In short, it involves sleeping with a shower cap over your hair (or just wearing one for a long period of time) in order to encourage a steamy, warm environment – hence the name “greenhouse effect” – that increases hair growth.  This method was popularized by Mika and Juvaun, and is, what I would call, the new “growth bandwagon.”

But wait … isn’t this just another name for the “Baggy” Method? No.  The “Baggy” Method focuses on helping the hair retain moisture and thus length; it also requires the use of a moisturizer and/or conditioner prior to “baggying”.  In contrast, the GHE Method focuses on growth from the scalp, and only natural oils or butters may be applied to the hair prior to putting on a shower cap.

So now you are probably asking: Does this GHE Method actually increase hair growth?  Well, given the many testimonies from relaxed and natural ladies, it appears to do so … but does it actually work?  Let us take a closer look at some of the claims people have made about the GHE method:

1. Increased sebum production “nourishes the hair and helps it grow”

Sebum, as many of you probably know by now, is a substance that is secreted from the skin for the purpose of lubricating the skin and hair.  The sebum that comes from the scalp can be thought of as a “natural oil treatment,” if you will.

So, how does this relate to the GHE method?  After period of wearing a shower cap, the heat from the head produces a warm environment under the cap.  When the cap is worn for hours at a time, the scalp may begin to produce more sweat and sebum.  Now, sebum can help with length retention and alleviating a dry scalp, but can it help with actual growth from the follicles?  I doubt it can.  (Check out this interesting study on vellus hair growth and sebum excretion: Blume U, Ferracin J, Verschoore M, Czernielewski JM, Schaefer H. “Physiology of the vellus hair follicle: hair growth and sebum excretion.” British Journal of Dermatology, 1991 Jan: 124 (1): pp. 21-28.)

2. The heat increases blood circulation in the scalp, thus increasing hair growth

The application of heat to the back, leg, or other part of the body can stimulate blood flow to that particular region.  (That is just the physiology of the human body.)  Thus, the heat that is produced with the GHE Method may help to stimulate blood flow to the scalp.  Our blood carries vital nutrients to various parts of the body, so it would make sense that more nutrients might be reaching the follicles of the scalp with the GHE Method.  With increased nutrients follows optimal hair growth?  Possibly.

3. It helps to retain more moisture, which “boosts hair growth”

In addition to heat production there is condensation (that is, water vapor transforming into liquid water) in the shower-cap environment.  Because our natural hair loves moisture, the GHE method can be good for replenishing and retaining moisture.  That in turn can help with length retention, but what about hair growth?  I have not found any information that supports a relationship between moisture and hair growth from the follicle.

4. The sweat and steam detoxify the scalp

As mentioned earlier, the warm environment created with the GHE method can induce sweating.  However, the main purpose of sweat is to regulate the body’s temperature (by cooling the body upon evaporation); sweat does not “detoxify” the body.  We have organs within our body – liver, gastrointestinal tract, kidneys – that take care of that task.  Additionally, sweat is primarily water with just a small amount of elements and minerals (none of which are toxic), such as iron, calcium, and sodium.  That being said, the GHE Method more than likely cannot detoxify the scalp.

So, after examining each of these claims, does the GHE Method really help the hair grow?  Well, it is possible given a stimulation of blood flow to the scalp induced by the heat formed from wearing a shower cap for a prolonged period.  However, you might really not know until you try it for yourself!  You can read more about the method here.

Ladies, have you tried the GHE Method?  What has been your experience?

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  • Tyrena

    When the air is dry my dries out fast, the green house effect keeps my hair moisturize which helps my hair from breakage. I use a little water a natural oil cover with pastic cap but a scarf on and go to work or anywhere when I get home I take them off hair nice and soft and moisturized.

  • AJ

    I have tried the GHE and I do it after every Aphogee protein treatment to put the moisture back into my hair. I can’t say weather out has worked when it comes to length but it makes my scalp and hair feel better. My new growth is always softer and it makes for easy comb after the oil has soaked into my hair from the heat.

  • Robyn C

    Applying this method at least 5 times a week, has definitely allowed my to retain 8 inches of hair growth with regular trims in 1 year. Allowing me to go from NL to APL, after being stuck at NL for two whole years and my 3C hair is a 100 times healthier and less frizzy than it was before.

  • Bella

    Nice article, but you don’t sound like you wanted to write it. I read it and feel a lot of doubt concerning the article and that you don’t believe that the method can grow hair. I don’t know if I’m making sense. But very helpful information :)

    • ify

      yes your right i felt the same way too it was like she was doubting if GHE really works for the hair but she made us understand what exactly is GHE and what it does for our hair

      • Rocki Ferg

        This lady doesn’t believe anything works. I read her articles and cringe every time!

  • Cher

    I feel like dropped a bit of science on this bandwagon. I feel like while so many people say going “natural” is a movement and so on, people treat it like a fad and will try just about anything including putting “anti-fungal cream” on their hair to make it grow. I am glad someone wrote what I was thinking about the basic facts of GHE. I think like any other method, we should examine if this good for us as individuals and as a group. Thanks for providing much needed insight.

    • Kera

      What science did you drop? There isn’t anything unnatural about the GHE. The moisture created by the shower cap opens the cuticles in the strands and allows the oils to penetrate deeper instead of lying on top of the hair. You put a NATURAL oil on the hair (ie. coconut, olive, grapeseed, etc.) and then put on the plastic cap. No chemicals or harm done yet, right? You sleep in the cap allowing the heat that NATURALLY RISES FROM YOUR HEAD to be caught in the cap, promoting blood circulation and increased sebum production, a NATURAL oil that our bodies secrete! The GHE was not intended to increase growth only to RETAIN LENGTH by moisturizing and nourishing your hair.

  • Angelita

    I don’t know about how it affects the scalp, but anyone that’s ever had a cast for a while can confirm that the hair under that cast grows a lot faster than it should and is actually very disturbing. So it could be true for the hair.

    • MOTZ1031

      I agree, while I did not have a cast, my 8yr old son did. When the cast was removed after a month he had quite a bit of (visible) hair on it.

  • Dreadlocksdownmyback

    So heres a wrench. I have a problem with dandruff. Dandruff is a fungus and it likes darkness and moisture. I feel that this will simply worsen that problem.

  • missnew

    Well I’ve tried it for about half a year and it took all my dam hair out. This is just another fad I think. A week after I started I noticed my hair felt like dam strings & every time I rub my fingers through it it would shed excessively. I’m not sure if I over did it (5 hours a day, sometimes 6), but even on days when I did it 3 hours or whatever I still saw more lost then gain. Everybody hair is different and reacts to certain things in certain ways, but this method is definitely not for me. I have mixed curly & wavy hair. Not sure if it has to be real coarse afro hair or what, but this shit took my dam hair out. I was bald as a dam newborn muskrat. Never again child. Never again.

    • NotSoNew

      I agree, everybody’s hair is different. But it’s incredibly hard to believe that you tried this and were constantly losing hair daily. Why would you continue using this method if your hair was shedding and breaking continuously? I think you’re just a troll trying to discourage other women.

  • mickeyb504

    I will try this method starting today after i come from jogging….I will first wash and deep condition my hair and then two strand twist my hair until it dries completely…i will then and take my twist down and spray it with my water and oil mixture and seal it with my mango butter mixture i will then put my shower cap and scraf on and leave on for 4 hrs….4 hrs every night I will do this for a month and re update my post

  • Trina

    What does your opinion matter? This method has already been proven to grow hair by Meeka lashauna and countless other you tubers. When done accurately they received twice the new growth in a month. Usually 1 inch.

  • Dee

    I started this method last nite. My hair is braided down in cornrows and I plan to make it last 1 month while I put my wig over it during the day and GHM at night.

  • Mastermind

    It works! This is the only consistent think I’ve been doing for the past 3 months and I’ve gone from barely APL to BSL in 3 months.

  • Julia

    Hay, I just want to know if you can do the GHE without shampooing and conditioning. Anyone can respond, let me know A.S.A.P.

    • yes u can. i do

  • Lunye Ladybug Fowler

    For me it does make a difference in the health of my hair. It is like in the 80’s when everyone was wearing those curls. They would put that oil on their hair and those plastic bags on it. Most people that wore curls seem to have grown their hair much faster than people with relaxers or who were natural. The steam effect and the oils, I think made the difference.

    • MIA

      Good point

  • MIA

    Some of this article is not true, the body does detoxify itself through sweating since the skin is the largest organ we all have. Also since the sebum helps with length retention could it not help with hair growth at the follicle since this is where the sebum is coming from?

  • Jessica Scarlett

    I just started this method a couple days ago so far I have noticed that my hair is really soft without adding additional products. I have really thick and coarse 4 mix type hair so I love that part so far my only problem is that my scalp is itches constantly. As of right now I use oils and raw shea butter on just my hair when doing this method. I would like to know your ideas.

    • LaToya Penn

      So are you supposed to wet hair then add oil or apply oil to dry hair then put bag on?

      • Jessica

        I would wet my hair first then oils

  • MissS

    My hair and scalp have responded positively to this method. I notice that my naturally dry scalp and hair is much softer and moisturized for longer periods of time. I have noticed that in the month I’ve been using this method to prevent my scalp and hair from drying out that my roots has gotten slightly thicker. It’s seems as if my hair has gained some fullness and a slight increase in length. While I’m not using this method to grow my hair, it’s nice to witness the additional benefits!

  • Ariel

    Primarily used for keeping my hair moisturized and it works well for me. Especially in my crown area where I tend to have the most breakage.

  • Kadisha

    How often should you do this and not shampoo or cowash for? I am currently on day two of doing the GHE. I let it breathe for a little while today, then re applied oil and butter (moisturized and sealed) then put the caps back on. Is that the correct way to do it?

  • Ashley Malik

    Recently my boyfriend told me he noticed he was losing his hair maybe because he was under a lot of stress at the office and the men of his family have suffered of alopecia; he tried some products with no results. then after i consult with my brother who have a same problem and he told me about NuhairRX Serum and brought it for I gave it to him to see if it might help him with the problem, he have been using it for a while and the difference is noticeable. This serum provides the necessary nutrients to reduce hair loss and increase hair thickness; in a short period of time his hair looks thicker and healthier.