Tuesday, February 7, 2017

Scientifically tested, over-the-counter treatments for thinning hair

Please remember that this information can and should never replace the care and advice of a physician. If you experience hair thinning, seek consultation with a medical professional who listens and will physically examine your scalp. If you take medications on a regular basis, always check for interactions between medications and supplements.

Be aware that scalps can be sensitive to any and all treatments and products, including natural ones. Scalps that are losing hair may be more sensitive than scalps in which hair density is stable.

This post has lots of links. Where I can link you to a full article, I did. Otherwise, I linked to abstracts, which contain a summary of the study's contents.

Updated: January, 2021

Androgenic alopecia is the clinical term of male and female pattern hair loss. It’s one of those diagnoses of exclusion. If you don’t have telogen effluvium (hair loss following an exposure to an allergen, due to physical or mental trauma), or alopecia areata (patches of hair loss), traction alopecia due to tension on your scalp, or hair loss due to thyroid disease, scalp disease or polycystic ovarian syndrome - then you likely have androgenic alopecia.©Science-y Hair Blog 2017

If you start to experience hair loss that is more than you are accustomed to, it’s ideal to have a doctor or dermatologist check for other causes of hair loss before concluding you have androgenic alopecia. Hair loss can be a sign that something else is wrong.

Female pattern hair loss and male pattern hair loss take on different patterns, which you can find men's here and women's here. ©Science-y Hair Blog 2017

Androgens are hormones which are more abundant in men than women, specifically testosterone. Testosterone circulates in your blood and in the hair follicle, can be transformed into dihydrotestosterone (DHT) by the enzyme alpha-5 reductase in your hair follicles. This is thought to be damaging to hair follicles. The end result is that hair follicles begin to produce narrow, “vellus” hairs. Like the hairs on non-hairy parts of your body, they are very thin, narrow and difficult to see. As these replace normal-width hairs on your head, overall hair thickness decreases.

Note that the "DHT-causes-hair-thinning" idea is not unequivocally proven. There are other variables at work on scalps with thinning hair like low-grade inflammation and atopy (allergy to airborne allergens, contact allergens, yeasts in normal scalp flora).©Science-y Hair Blog 2017

There are some proven treatments for Androgenic alopecia which work in a variety of ways. These are ones you can buy over the counter, they don't require a prescription. Some of them you can use together because different treatments address different causes of hair thinning, such as enzymatic pathways or circulation or inflammation. If in doubt, ask a pharmacist, doctor or dermatologist.

1) Minoxidil. For example: Rogaine. Minoxidil must be applied twice daily as indicated on the label. ©Science-y Hair Blog 2017
Everybody (women and men) can to use the 5% men’s strength to get the best result.
Minoxidil must be used twice daily to achieve the best result. Minoxidil is effective in around 50% to 60% of people who use it. Minoxidil is a vasodilator (expands blood vessels to increase blood flow).

2) Topical caffeine.  
It has to go on your scalp, drinking caffeinated beverages doesn’t count. 

Caffeine is a quickly-absorbed vasodilator to increase blood flow in the scalp. Caffeine does not need to stay on the scalp until the next washing (that's why shampoos work), but it does need about 2 minutes to absorb into your skin before rinsing
In men especially, topical caffeine may decrease trans-epidermal water loss, which means skin stays hydrated.
The concentration used in the studies linked here, done in the lab (not on people, just their hair follicles/skin in the lab) is 0.001% to 0.005% - very low for an active ingredient, but enough to be effective. 

In a 2018 study done on men with androgenetic alopecia (in vivo), a 0.2% caffeine solution was used twice per day, increasing the number of hairs in the growing phase (anagen) by almost 11% - similar to the results from Minoxidil in the same study.

Topical caffeine affects the whole body and too much on your skin is the same as too much when ingested. Larger concentrations can be dangerous. If you're caffeine-sensitive, topical caffeine might keep you awake if you use caffeine in products at night, or give you a "caffeine buzz" during the day. 

In lab tests on skin in culture which was treated with testosterone, hair growth was suppressed. When topical caffeine was added, it stimulated hair growth back to normal, so caffeine may counter hair-thinning effects of testosterone in hair follicles.
Caffeine stimulates hair growth and helps hair stay in anagen phase longer - the growing phase - than it otherwise might in people with androgenic alopecia.
Caffeine may slow down excessive shedding and stimulate hair growth.
Topical caffeine has been measured to stay active in hair follicles for up to 48 hours, so it needs to be used every 1-2 days to be most effective.©Science-y Hair Blog 2017

There are a number of products - shampoos, sprays, serums you can purchase which already contain caffeine. Some contain additional ingredients which may be beneficial. There is a do-it-yourself recipe following this list.

Caffeine-Containing Hair Products

Alpecin Caffeine shampoo (with ketoconazole)
Alpecin After Shampoo Liquid
Amplixin Intensive Hair Growth Serum
Art Naturals Organic Argan Oil Hair Loss Shampoo 

Broo Thickening Shampoo
ConditionMe Hair Growth Conditioner - Watermans UK brand 

Dove Men + Care Fortifying 2 In 1 Shampoo, Complete 2-in-1 shampoo 
GrowMe Shampoo, Sulfate Free - Watermans UK brand
Hair Lab Hair Growth Serum
Hair Lab Regrowth & Thickening Shampoo
Man Cave Caffeine Shampoo
Pura D'Or Anti Hair Loss Argan Oil Shampoo (with pyrithione zinc) (Sulfate free)
Revita Hair Stimulating Shampoo (with ketoconazole) (Sulfate free) (Not suitable for vegetarians)
SebaMed Scalp Activating Shampoo for Thinning Hair 

The Ordinary Multi-Peptide Serum for Hair Density
Thicker Fuller Hair Shampoo
Thicker Fuller Hair Weightless Conditioner
Ultrax Hair Surge Caffeine Hair Growth Stimulating Shampoo
Ultrax Hair Solace Conditioner
Ultrax Labs Hair Lush Thickening treatment serum
Wick and Strom Anti Hair Loss Shampoo (with ketoconazole)

DIY caffeine recipe: Here are 2 options.

Option 1) Lower concentration, ready to use without further diluting - but dilution may be a good idea:
Mix the contents of one-fourth of a 200 mg capsule of caffeine powder (such as this one with no fillers or additives) with 1 gallon (about 4 liters) distilled water.  Using too much caffeine can cause the same side effects as ingesting too much caffeine, or can cause scalp irritation.  Overdosing on caffeine can be very dangerous for people of any age!©Science-y Hair Blog 2017 
The end concentration is approximately 1.25% to 1.3% with this mixture. I recently updated this concentration due to a arithmetic error.  This is more concentrated than necessary - but we're working with really small amounts that require much more sensitive equipment than most of us have!
I encourage you to dilute this before using it. Use 1 part caffeine-water, 3 parts water or shampoo or whatever you are adding the caffeine water to.
The caffeine-water could be mixed with a shampoo (when using, don't dilute a product in its bottle), or made into a spray or put in or in a dropper-bottle to apply to the scalp.

Option 2) Higher concentration, needs to be diluted to use: Add the contents of a single, 200 mg capsule of caffeine powder (with no additives) to 1 gallon (about 4 liters) distilled water. This is your highly concentrated solution. Dilute this solution to make sprays or scalp "drops" or to add to a shampoo by using 5% to 10% caffeine solution in your product. For example, 5 grams caffeine solution per 100 grams total product is 5%. To be exact, 5% caffeine solution + 95% "everything else" = 100%. I make shampoo and a leave-on scalp gel this way.

Can brewed tea or coffee be used?
Yes. But not decaffeinated tea or coffee. Tea and coffee can create or enhance "cool" or ashy tones in hair. The tea or coffee needs to contact your scalp and be left on for at least 2 minutes.
3) Ketoconazole shampoo

Ketoconazole is an anti-fungal medication that can help reduce hair loss - it’s sold for managing seborrheic dermatitis - dandruff. Higher concentrations are found in Nizoral shampoo, and Regenepure DR in the US. There are some shampoos with both caffeine and ketoconazole in the list above (Alpecin Caffeine shampoo, Revita Hair Stimulating Shampoo, Wick and Strom Anti Hair Loss Shampoo). Ketoconazole may help by ultimately reducing inflammation, or by interfering with the alpha-5 reductase enzyme. ©Science-y Hair Blog 2017
Ketoconazole shampoos are used every 2-3 days in studies that showed decreased hair loss by about 17%, a greater number of hairs in anagen phase (growing phase), greater hair density and width (compared to narrowing hairs with androgenic alopecia).
It may be especially helpful for thinning hair if you have ever had seborrheic dermatitis, eczema, rosacea, or itchy scalp or any sort of scalp flaking, including little powdery dry flakes.
Results are similar to 2% Minoxidil - which is response in approximately 40% to 50% of people using it.
4) Pyrithione zinc shampoo

This is another dandruff shampoo that can decrease inflammation in the scalp and slow hair shedding (by about 10%). It may or may not encourage more normal-width hairs to grow, depending on the study.
It may be more helpful if you’ve ever had seborrheic dermatitis, eczema, rosacea, or itchy scalp.
Use a pyrithione zinc shampoo every 2-3 days.
5) Pumpkin-seed containing supplement (with other active ingredients) 

A pumpkin seed-containing supplement in one, 6-month study which was double-blinded and placebo-controlled (the gold standard for studies such as this) had a positive effect on hair re-growth in men with mild to moderate androgenic alopecia. That translates into 40% increases in hair counts in men treated with pumpkin seed oil after 24 weeks versus only 10% increases in hair counts for men in the placebo group.
In animal studies, pumpkin seed oil alone has been demonstrated to block the action of alpha-5 reductase.
The dose was of 4 capsules, 2 were taken with a morning meal and 2 with the evening meal. 

The specific supplement used in this study was
Octo-Sabal Plus” which is not available in the U.S., containing : Octacosanol, Pumpkin seed powder, Mixed vegetable powder, Evening primrose powder, Corn silk extracted powder, Red clover powder, Tomato powder. These are not inactive ingredients, they have systemic actions - and they are probably synergistic, working together to have the end effect.

  • Red clover extract is a phytoestrogen (plant estrogen), corn silk extract contains plant sterols which may help with glucose metabolism. Phytoestrogens from plants may modify the onset of androgenic alopecia by reducing inflammation around hair follicles.
  • Octocosanol may have mild anti-inflammatory effects and/or improve lipid metabolism (cholesterol, for example). 
  • Tomato powder may reduce inflammation and improve lipid metabolism.
  • Pumpkin seed extract may interact with alpha 5 reductase and aromatase, which may have an impact in how alpha 5 reductase affects hair follicles.

Pumpkin seed oil may also support nitric oxide formation, an effect which may be supportive of healthy skin barrier function

A tablespoon or about 15 ml of pumpkin seeds contains about 5 grams of fat (oils), which is 5000 mg - more than used in this study. If you regularly eat pumpkin seeds - it may be having a similar effect. And you get other nutrients too!
6) Protective foods and nutrients: 

  • Regular consumption (1-3 days per week at least) of soy beverages (for the phytoestrogen content). One study of men with moderate to severe androgenic alopecia (including more of the scalp) found that regular consumption of soy beverages and higher vanadium intake appeared to be protective of hair thinning. It is a study done in Taiwan, of men only.
  • Higher vanadium intake. Having an adequate intake of vanadium, which is especially high in shellfish, mushrooms, parsley and dill, is correlated with a lower likelihood of having moderate to severe androgenic alopecia, mild androgenic alopecia is still possible. 
7) Protective behaviors: Sleep
Sleeping for fewer than 6 hours each night is correlated with more widespread hair thinning in men with androgenic alopecia (in the reference linked in #6). I know, you don’t need to hear that, busy people and night owls. Get 6 to 8 hours of sleep every night!
8) Nigella sativa oil (topical), aka black cumin seed oil for telogen effluvium.

One double-blinded, placebo controlled study (pdf link) showed this oil, diluted and applied topically, can be helpful in re-growth of hair after telogen effluvium, which is significant hair loss following childbirth, serious illness, major surgery, exposure to severe allergens or irritants, severe emotional stress, significant weight loss. Acute telogen effluvium can persist up to 6 months after the initial provocation, but it lasts typically 3-6 months. Chronic telogen effluvium lasts longer than 6 months and can last for years. It is spread over the whole scalp, not in a pattern like androgenic alopecia although one may have thinning at both temples.

The “recipe” used in the study is 0.5% Nigella sativa oil, 3% glycerin, 0.4% lavender oil, and 60% alcohol, adding water to make up the balance of 100%. You should not put Nigella sativa oil on your scalp undiluted.
This was applied daily to the scalp for 6 months.
At 3 months, 9 of 10 patients receiving this treatment had increased hair counts, and half continued to have increased hair counts at 6 months.
Placebo-treated patients had improvement in 6 of 10 at 3 months and 6 months showed hair loss rather than increase.
Can you create this formula at home? Yes. You need a scale. This would usually be formulated with ethanol as the alcohol. the “60%” is a volume or weight, not a percentage alcohol or “proof.”
So if you were making 100g of this, you’d use 0.5g Nigella sativa oil, 0.4 g lavendar oil, 3 g glycerin, 60 g ethanol (vodka, or something with the highest proof number you can get) and just under 40g water.
What about another application method? If you oil your scalp overnight, add 1 teaspoon (5 ml) Nigella sativa oil to 1/2 cup (4 oz., 125 ml) oil of your choice and use that mixture lightly on your scalp. Add 1/4 to 3/4 teaspoon lavender essential oil if you like that fragrance better than smelling like cumin.

9) Melatonin (topical)

One study of topical melatonin in androgenic alopecia found that both men and women, treated with a 0.0033% melatonin solution (with other ingredients) experiences a reduction in hair loss of up to 60%. Seborrheic dermatitis was also improved, when it was present. Melatonin may work through an anti-oxidant effect on a scalp experiencing oxidative stress. ©Science-y Hair Blog 2017

Products for the scalp containing melatonin include Asatex
One "Full dropper" of this liquid melatonin product in 100 grams water will equal approximately the concentration used in the study linked above.
Melatonin products are applied to the scalp daily or taking 1 or 2 days off per week.
Because we have melatonin receptors in our skin, you may experience some sensations of sleepiness or dizziness after applying such a product, just like melatonin supplements. People who have asthma are cautioned to avoid melatonin, and probably need to avoid topical melatonin too. Use with caution! 
DIY leave-on melatonin: If you have a scale that weighs in tenths of milligrams, you can use a powdered melatonin with no fillers like this one. The final concentration would be 0.3 mg melatonin per 100 grams distilled or deionized water. But it won't dissolve in the water. First, mix the melatonin powder with glycerin. Use as little glycerin as you need to get it to dissolve so it won't be sticky. Once it is dissolved, add the water to the glycerin/melatonin mixture. Use this as a spray or in a dropper-type bottle to apply to the scalp.

10) Essential oils 

10 a) In one study, 44% of participants treated with a blend of essential oils in a carrier oil blend (compared to only 6% of the group who used the carrier oils without the essential oils) experienced improvement in return of hair with this particular form of hair loss. The study is linked here and they provide their formula (Scroll down to "Materials and Methods). 

These essential oils have anti-inflammatory, anti-microbial effects and can promote healing in skin. The oil was applied to the scalp at night (every night), massaged for 2 minutes, then wrapped with a warm towel. No mention is made of whether the scalp/hair was washed in the morning.
This was done nightly for 3-7 months.

This formula is not without risks. Essential oils, even diluted, can cause scalp irritation (which can provoke hair loss - ironically). People with seborrheic dermatitis or very sensitive skin may react badly to the application of oils to the scalp, or may be sensitive to the essential oils. The fragrance of this blend is very strong!

10 b) 3% Peppermint oil produced (in mice) a better result in a leave-on solution than 3% Minoxidil (which is not full-strength) for inducing hairs in the growth (anagen) phase and increasing follicle number. Results were visible at 4 weeks in shaved mice.

10 c) Rosemary oil proved to be as effective than 2% Minoxidil (which is also not full-strength) at increasing hair count by 6 months. I have yet to access the full article to learn the concentration of rosemary oil, but my impression is that it would be similar to the concentration in the first article linked in this "Essential Oils" section - but without the other essential oils.
11) Red Clover extract with Acetyl Tetrapeptide-3 (topical)
This ingredient has been shown to inhibit the alpha-5-reductase enzyme, encourage collagen production in the hair follicle (which may stimulate hair growth - this is not entirely clear), and inhibit some pro-inflammatory compounds in the skin. After 4 months of treatment, in a small (14-person treated, 15 placebo) study, the treated group had significantly (statistically significant = unlikely to be due to chance) more hairs in anagen phase - new hair growth - than the untreated group. 15% more hairs in anagen phase than the untreated group. There was also a reduction in hairs in telogen -getting ready to fall out- phase - was about 30% fewer than the untreated group. That means a net gain in hairs both growing in new, and staying on the scalp longer before falling out. This study was published in the Journal of Cosmetic Science (pdf link). For people with male/female pattern hair loss, that means hairs stay growing for a "normal" life span rather than a shortened life span typical of pattern hair loss. Bear in mind - this is a very small test group!

The treatment was left on, and based on the molecular weights of the active ingredients, a leave-on treatment may be more effective than a shampoo.

You can find these ingredients in:
  • Alterna Caviar Clinical Root and Scalp Stimulator
  • Amplixin Shampoo
  • Amplixin Conditioner
  • Beauty Facial Extreme (BFE) Hair Regrowth Serum
  • Dermalogic Hair Growth Serum
  • Keranique Follicle Boosting Serum
  • Peter Thomas Roth Hair To Die For Treatment Serum
  • Strong Hairpro Deep Scalp Hair Therapy
  • Shea Moisture Jamacian Black Castor Oil Strengthen and Restore Shampoo (only red clover extract)
  • The Ordinary Multi-Peptide Serum for Hair Density


  1. Brilliant! I love your blog I learn a lot with your posts since my hair is not my best asset... haha
    Please, don't stop posting! <3 :D lots of love!

  2. Thanks for doing the research to find these treatments! In #8 using the black cumin oil, is it an essential oil? Is the lavender also an essential oil? I'd like to give this a try. What kind of ethanol can be used in this?

    1. Hello Lily,
      The black cumin seed is an essential oil, but it also is used as a supplement, so it comes in larger bottles. The lavender is an essential oil too, but it was used in the placebo and did not have an effect in hair growth. It probably improves the scent, but 0.5% black cumin seed oil doesn't smell very cumin-y for too long.
      There are shampoos which contain black cumin seed oil which might be easier.
      The ethanol is probably 200 proof, or that would be my guess, things found in labs. For home-creation, I would use the highest proof ethanol you can get. Vodka comes to mind.

    2. Thank you!! Which of these might be the most helpful for hair loss associated with a lupus flare? I currently follow the curly girl method...cowashing and using products without sulfate or silicones.

    3. Hello Kimberly,
      Discuss any of this with a doctor or pharmacist first! You don't want to have an interaction with any medication you are taking. All of these treatments have potentially systemic effects. I think you might lean towards the anti-inflammatory like blackseed oil, which was helpful in telogen effluvium. There are some blackseed oil shampoos available - the total amount of the oil is low, so it will be listed near the end of the ingredient list. If you click the pdf link, there are photos showing the scalps of some participants before and after - and that "redness under the skin" of inflammation is gone.
      Of course, getting enough sleep is ideal and making sure your Vitamin D and ferritin levels are in good shape is helpful. If blackseed oil didn't irritate your skin - you could add it to a co-wash. It might smell - odd.
      Best wishes! W

  3. Thanks, Wendy! I was thinking Vodka, too, as an easily obtainable source. I'll let you know if I start this and my results. My biggest issue is not wanting to wash my hair every day or even every other day, as most treatments require a certain frequency for results - thus my preference for oral supplements, but this seem worth a try.

  4. Thank you so much for this. Keep up the good work! :)

  5. Hello :),

    Thank you so much for all this amazing content. I will try your caffeine diy spray. I was wondering how long it should stay on the hair? Also 2 min like you described in the shampoo section?
    Thank you so much!

    1. Hello Dammie,
      2 minutes on the scalp is enough time for the caffeine to be absorbed. With the spray - you can just leave it on your scalp. If you're worried about scalp irritation - you can cut the amount of caffeine in the recipe in half and you will still have enough active ingredient. Good luck! W

  6. Hey again. Awesome post. This is conoletely off topic but can you please do a post on the importance of pH level of haircare products. I've been trying to use more natural, (mostly fragrance free, fewet essential oils too) brands since my scalp gree sensitive anr my eyes and facial dkin are veryy sensitive to glycols and frangrances.
    But I've read that most natural brands and small business brands do not stay within a healthy pH range.
    NaturalhavenBloom did a pH test list for some popular salon, drugstore and 'organic' brands,but it was mostly incomplete. Could you possibly test some products yourself. I dont have access to pH strips here.
    I'd also love to know your take on this pH thing. I do know for example that using the wrong amounts of anything too basic or acid can ruin thr hair long term and break the hydrogen bonds(similar to chemical porcessing) but I'd like more info on that though.
    Link to the article mentioned:

  7. Hey again. Awesome post. This is conoletely off topic but can you please do a post on the importance of pH level of haircare products. I've been trying to use more natural, (mostly fragrance free, fewet essential oils too) brands since my scalp gree sensitive anr my eyes and facial dkin are veryy sensitive to glycols and frangrances.
    But I've read that most natural brands and small business brands do not stay within a healthy pH range.
    NaturalhavenBloom did a pH test list for some popular salon, drugstore and 'organic' brands,but it was mostly incomplete. Could you possibly test some products yourself. I dont have access to pH strips here.
    I'd also love to know your take on this pH thing. I do know for example that using the wrong amounts of anything too basic or acid can ruin thr hair long term and break the hydrogen bonds(similar to chemical porcessing) but I'd like more info on that though.
    Link to the article mentioned:

    1. Hello Mamli,

      I am familiar with The Natural Haven Blog and that particular post. I don't own very many products and I can't use most products due to sensitive skin, so I would have to buy a bunch of products I cannot use. That presents a logistic problem.

      The range of pH at which hair is is most resilient (least likely to swell up or be weakened) is between 4.5 and 6. But many people's hair tolerates pH outside that ranges for short exposures. If one uses a product with a pH of 8 or 9, like baking soda solutions or real soap - hair may swell and that is stressful and dehydrating. The same applies to low pH, some people's hair swells in low pH solutions like acidic rinses.

      Most hair products are in the "safe" pH range because that is where preservatives are also most effective.

      The products that would always be high pH are soaps, natural soap whether bar soap or liquid soap. But also shampoos containing soap, which may be listed as Sodium Cocoate and Potassium Cocoate, Sodium Olivate and Potassium Olivate, Sodium Palmate, Sodium Palm Kernelate, "Saponified oils of _____."

      I'll give some thought to how I might find the pH of products I don't own.
      I do have a post with pH of common homemade rinses here: http://science-yhairblog.blogspot.com/2013/08/ph-of-common-homemade-rinses.html


  8. Hello! First, I love your blog! I follow everything you write and I admire your work very much.
    I would like to know about storage of the caffeine spray. I live in Brazil, Rio de Janeiro and here we face high humidity and I'am worried if I can do this amount and use until the end (expiring date), and how i can stock (fridge or closet).
    Sorry about my English =/

    1. Hello Thais,
      It might be best to store your caffeine spray in the refrigerator in a hot, humid climate. Good question! Also, the caffeine that you buy to use to make the spray needs to be kept in a cool, dry, dark place.
      If you start out with distilled water or boil some water and let it cool before making the caffeine water, it should be free of bacteria and molds, but bottles and surfaces can contaminate your product. So it is better to be safe and keep it refrigerated. I hope the caffeine spray works well for you! -W

  9. Hi. Great article. What about many of the herbs used as part of ayurvedic hair practices? Bhringraj is supposed to perform as well as minoxidil? I would love to hear your thoughts/assessment about it.

    1. Thank you, MzTeaze! I will look into it and add it to the post. It looks like the studies have only been done on mice and rats so far. Looks promising. -W

  10. Can I use caffeine powder instead? It's cosmetic grade. Can I add it to FSG?

    1. Hello mparmpadeli,

      Yes you can use a powder. But you need a very sensitive scale so that you can weigh out 0.005%. Which is 0.005 grams per 100 grams. If you were making a liter or a gallon, multiply that amount by the volume of water you're using.
      Using too much caffeine could be dangerous. Even doubling the amount can cause a caffeine "buzz" - for people with heart problems, kidney or breathing or anxiety problems, excess caffeine could be a health hazard.

      You could add it to flaxseed gel, but it would be better for measuring and mixing's sake to make the caffeine-water first, then prepare the flaxseed gel with the caffeine-water. Heating to boiling will not change the effects of the caffeine - the boiling point of caffeine is higher than that or water.

      I'm not sure what good it would do the scalp, though. Unless you apply flaxseed gel evenly to the scalp, coverage will be very spotty

  11. Hello and thank you for such great information.Would infusing oil with green tea leaves be effective? Can you tell me what the ratio would be for green tea leaves to oil to get the affective amount of caffeine? Thank you

    1. I don't think infusing oil with green tea leaves would work for caffeine. Caffeine is water-soluble and might not end up in the oil.

  12. Terrific article. Could Rogaine be used along with Alterna Caviar Clinical Root & Scalp Stimulator (Red clover extract)

    1. They might be used at the same time, at least based on how they work. Rogaine has different "targets" than the red clover and acetyl tetrapeptide-3
      But using 2 topicals always creates the potential for reactions between products (and your skin) so it would be best to test both out on a small patch of skin and watch how it responds for about 3 days before trying it all over your scalp. If you were to experience a sensitivity reaction (which can cause hair loss!) or if the 2 products were to not mix well and create an unpleasant residue, you'd want to know that before committing all your scalp to the treatment. Good luck - W

  13. How do you calculate the percentage of caffeine in your diy solution? I am calculating it as 200mg/4000 ml, and coming up with 5%, rather than .005 per cent. I have read that solutions greater than 2% can cause hair loss - obviously not the goal! I am no scientist or mathematician, so am I calculating this incorrectly?

    1. Hello Linda, You're right, I neglected the last step of the percentage calculation. I have corrected the "recipe" above. It still errs on the more-concentrated side. I like to mix the caffeine water with shampoo for ease of use, thus diluting it further.

    2. Thanks! I am definitely planning to use the water in my refresh solution, so fingers crossed!

    3. hi,thank you for your answer and thank you to linda for the data.i have a question,im really bad at maths so here goes.instant coffee has 0,007 gr caffeine per teaspoon.which is the proportion i need? i mean per cup-liter or whatever.sorry for my english.

  14. the nigella sativa oil study said they only used 2 ml per day to treat the scalp. i feel like that's not enough solution at all, even if you are treating a few problem area vs. the entire scalp. do you have any insight on this? Thank you so much

    1. I think the oil mixture was left on, if I recall correctly. If one applied 2 ml of oil to the scalp with a dropper or pipet, it could be spread around to cover the scalp unless hair is extremely dense - which we're assuming was not the case. I read studies like this and think, "yeah, right" as I try to imagine fussing around putting dots of cumin-scented oil mixture on my scalp daily for any length of time. It would almost have to be applied in either strips or dots all over the scalp and then rubbed in.

  15. Herbal Essence has a volume shampoo and conditioner that has coffee fruit in it do you think that this might work? Thanks for your help.

    1. Hello Janet - I think I would want to see "Caffeine" on the ingredient list to be sure that was what I was getting in the product.