Sunday, May 20, 2018

Hair Loss: Nutrient Deficiencies, Supps, Herbal Shampoo Ingredients, and Egg Yolk Hair Masks for Alopecia | Plus: Carcinogens & Endocrine Disruptors in Your Shampoos

While women will (comparatively) rarely go completely bald, they have the same problems with thinning hair as men do... and diet (from nutrient deficiency to excess - esp. vitamin A + D) are primary drivers of hair loss in both, men and women; and that despite the fact that deficiencies of both retinol and 25OHD contribute to hair loss, too (Rushton 2002; Guo 2017).
I've written extensively about "conventional alternative" treatments (alternative = avoiding 5-AR inhibitors that block the conversion to DHT and not paying for a transplant) roughly a year ago in "Hair Loss: Finasteride, Laser Light or Minoxidil - What Will Really Help Men & Women Regrow Lost Scalp Hair?" (re-read it).

In view of the fact that this is still one of the more popular articles and considering the interest many of you showed in a recent Facebook post of mine that included the list of nutrient deficiencies, ailments, and behaviors that may cause hair loss (Table 1) on Facebook, I decided to re-address the issue. This time with a focus on the former, i.e. dietary and behavioral factors that promote hair loss and potential ways to address them while avoiding increasing your exposure to carcinogenic endocrine disruptors from cosmetics.
Looking for more ways to improve your diet? Increase your potassium (K) intake!

Potassium vs. Diet-Inducded Insulin Resis.

In the Lime Light: The Ill Effects of Low K Intakes

Bad News: Most Americans are Sign. K Deficient

Lean, Healthy ... Correlates of High Hair Potassium

Eating a High Protein Diet? Better Watch K!

Potassium Bicarbonate = Anabolic!?
To begin with, let's briefly readdress why you may be losing your hair in the first place. As Rajesh Rajput Rajendrasingh points out in Chapter 71 of "Practical Aspects of Hair Transplantation in Asians" (Haber 2018), ...
"[... h]air loss is a derangement or disregulation [sic!] of the hair growth cycles in the body caused by multiple factors acting in tandem. There is a role of genetic predisposition. However, the outcome is influenced by environmental factors, pollution, stress, lifestyle, aging, diet, scalp care, and hygiene" (Rajendrasingh 2018).
Now, genetics and aging are (as of now) factors you can neither tweak (safely) nor avoid. The rest of the factors, however, may be addressed and could (no guarantees, here) allow/force your body to (re-)start replacing the 100% natural loss of hair with new hair, again (that's the way it's supposed to work - and no, science indicates, the cells rarely die, they just stop to reproduce hair).
Table 1: Tabular overview of various factors that may cause hair loss - apart from androgenetic alopecia, where the mechanism does not involve DHT as a mediator of hair loss (Rajendrasingh 2018).
Thus, "[t]reating hair loss is more about how to retain hair, strengthen the roots, promote hair growth, and stimulate the hair cycles to continue rather than fighting hair fall" (Rajendrasingh 2018).
This is particularly important because research indicates that usually less than 10% of the roots are affected in any given growth cycle, and thus it takes a few years for baldness to become apparent - even if your hair is already falling out without being subsequently replaced.
You will read all sorts of things about the (sex)hormonal origin(s) of hair loss, don't believe it! While both testosterone and estrogen have been shown to inhibit hair growth in the petri dish, epidemiological evidence shows that only DHT, not estrogen or testosterone levels are elevated in people with increased hair loss (in men | Kische 2017).
I've previously addressed low-dose 2% and 5% topical minoxidil applications, the use of medicated shampoos, and LLLT in last year's article (re-read it). This article is sort of a follow-up that will focus on diet (antioxidants, vitamins, and minerals) and selected supplements.
Table 2: Too much of a good thing - Side effects of excessive use of supplements that could help w/ hair loss (Guo 2017).
Obviously, the first stop on your journey to stopping hair loss is to make sure you avoid deficiencies in zinc, vitamin A, C, E, and D and check for typical triggers such as thyroid dysfunction or medication you may be taking for other reasons. Other reasons to address are...
  • potential toxins in your diet/environment - Since a toxin-free environment is required for the cells to divide, minimizing your exposure to agents that are known to cause hair loss - these include heavy metals, such as thallium and mercury, for which industrial and mechanical workers are at most risk for exposure, dietary supplements, such as vitamin A, insecticides, such as boric acid, and other more specific agents, such as colchicine, arsenic, excess selenium, botulinum toxin, Podostroma cornu-damae, and the synthetic opioid MT-45 (Yu 2018).
  • lack of catalysts required to facilitate metabolic processes required for hair growth - The former include some of the previously mentioned nutrients, i.e. trace elements such as iron, calcium, zinc, and magnesium that form the structure of the hair, but also amino acids, the building blocks for the hair, as well as vitamins (here in the broader sense) such as biotin (largely overrated according to Patel 2017), B-complex, vitamin C, and omega 3. All these vitamins, minerals, and nutrients, if
Talking in-depth and in an evidence-based fashion about the former would go way beyond the scope of this review - my advice thus is:

Reconsider the amounts of vitamin A (retinol in its various forms) and selenium you're supplementing with and stay away from processed junk food and known sources of heavy metals.

You want to keep the above in mind also when it comes to supplements. Even the "holy health grail", vitamin D (the hype supplement of the decade) has been shown to promote hair loss when taken in excessive amounts (Carlberg 1996). More doesn't help more!
The magic (peptide) is in the yolk: I am pretty sure you've seen women use egg-based "hair masks" in YouTube videos before, too. Be honest, did you laugh about such stupidity? Well, in this case, you may be the stupid one: It is both logic (hair mostly grows in a precocial bird) as well as scientifically proven that the yolk of chicken eggs contains a key hair growth factor. Nakamuro et al. (2018) were able to show that the VEGF stimulation and effects on human hair follicle dermal papilla cell growth are significant enough to be observed even if the eggs are not massaged into your scalp, but simply eaten ... well, certain peptides from the yolk, that is (note: in different but related contexts, i.e. healing burn wounds egg yolk has been used topically successfully | Yenilmez 2015).

Egg yolk peptides may facilitate hair (re-)growth in women. Female pattern hair loss patients were orally administered placebo or HGP-containing capsule (2x125mg) for 24 weeks. (A) Changes in Savin scale. (B) Number of subjects with improved hair growth; that is, number of decreased Savin scale subjects. (C) Photographs of subject scalp before and at 24 weeks after administering egg yolk peptide. (D) Hair density measured by phototrichogram (Nakamura 2018).
In their study, there were significant improvements in hair growth in both mice and humans who were fed a diet containing 0.1% of egg yolk peptides (mice) and 2x125mg of egg yolk peptides in supplemental form.

Next to the surprisingly visible results in the photo in the figure to the left, the paper that has been published ahead of print in the Journal of Medicinal Food shows that the water-soluble egg yolk peptides induce VEGF expression through insulin growth factor-1 receptor activation-induced hypoxia-inducible factor-1α transcription pathway... "Wait, IGF1?" If you are now thinking about the eggs vs. egg-white study showing 40% increased gains with whole eggs vs. egg whites, you are probably a similar science geek as I am... or simply remember my article from last year ;-).
What could help, though, is a supplementation protocol outlined by Rajendrasingh et al. in the previously cited chapter in "Practical Aspects of Hair Transplantation in Asians" (Haber 2018). It takes into consideration that 'anti-hair loss supplements' heavily compete for absorption and is thus a three-day protocol that avoids the simultaneous provision of agents such as iron and calcium, of which 30-40% are lost when they are administered together:
Table 3: Cyclical vitamin therapy for hair loss management as suggested in Rajendrasingh 2018.
In this context, it is worth mentioning that scientists dabbling in the field explicitly warn people not to consume multi-vitamins - especially the high(er)-dosed ones that are marketed to athletes might do more harm than good. Moreover, Rajendrasingh et al. (2018) advise that the "addition [of] topical application of biomimetic peptide[s] is advised every morning to promote hair growth [see infobox on egg], and topical minoxidil 2% in females and 5% in males is advised every night" to get the most from the previously outlined stack. Moreover, ketoconazole 2% shampoo is recommended once every 3 days and regular pH balanced shampoo twice a week or up to every day as desired. Plus: The optional use of LLLT hair growth for 20 min once a week may yield even better results.
Do not laugh about "alkaline diets" - They imply switching to healthier food options and that will promote both your health and performance!
Why's high protein a problem? You will probably have spotted it right away in Table 1 - fad-diets and high protein diets promote hair loss... supposedly! The explanation Rajendrasingh (2018) give, is not 100% convincing, though. He writes: "High protein diet leads to acidic blood pH which requires reabsorption of calcium to neutralize the acidity, leading to indirect calcium deficiency and hair loss". Furthermore, there is research suggesting that blood androgen levels will increase after high meat and fat meals - this could, in fact, promote hair loss in susceptible individuals.

Even if I don't think that that high protein (esp. meat) intake is the most common cause of hair loss, the solution Rajendrasingh offers, i.e. to "rotate the source of protein to include beans, dals, chickpeas, soy, mushrooms, milk, yogurt, egg, fish, and some meat" is good advice, anyway - low protein intakes will, after all, also promote hair loss, because protein is your #1 (and only) natural source of the previously listed amino acids that are required or facilitative for/to hair growth.
As far as individual dietary factors are concerned, the list of potentially useful nutrients (vitamins, minerals, etc.) includes...
  • vitamins: biotin (vitamin B7) for hair growth and dry skin; nicotinamide (vitamin B3) for its anti-inflammatory purposes; cyanocobalamin 'cause it prevents anemia; pyridoxine HCl (B6) which prevents anemia and water retention, vitamin C as an antioxidant, and prerequisite for collagen synthesis; vitamin A (moderate amounts) and vitamin E as antioxidants and cell-protecting agents; folic acid (B9) to help prevents anemia and facilitate DNA synthesis, and vitamin D (moderate amounts of <2,000 IU/d) to promote calcium metabolism
  • amino acids: l-histidine, tyrosine and lysine, which are required for/seem to improve hair growth; l-ornithine which promotes DNA and protein synthesis, as well as arginine, which is involved in rapid cell division, repair, and endothelial stability; taurine (2 aminoethanesulfonic acid), which has potent detoxing (in the real-science sense ;-) effects; glycine, which is an important precursor to biosynthesis of various proteins, as well as the sulfur proteins l-selenomethionine/sodium selenate and sulfur-methylsulfonylmethane 
  • Zinc is one of the candidates for totally overrated supps. Its benefits in T2DM are a result of increased insulin, not improved sensitivity.
    minerals: ranging from iron (preferably Ferrous fumarate), calcium and magnesium, over manganese, iodine, molybdenum to chromium, zinc, and (specifically important for the morons many people in the fitness industry are) copper, which (just as iron) can be depleted if you supplement with zinc like crazy (and NO you are not fat because you're zinc deficient, the opposite may be the case!)
  • others: potentially useful are also the fatty acid gamma-linolenic acid (GLA) for its anti-inflammatory prowess; para-aminobenzoic acid (PABA), which prevents premature graying of hair; inositol, which prevents hair thinning in women, in particular; green apple extract (probably the pectin), as well as all the proanthocyanidins, flavonoid, and catechins in berries, tea, etc. 
Saw palmetto, which is also on the original list of potential supplement candidates in Rajendrasingh (2018) is a natural 5-AR inhibitor of which I am still not sure if they are a good idea (at least not as a default therapy).
Figure 1: First rule of controlling hair loss - Get your dietary ducks in a row.
An important part of getting your nutritional ducks in a row (see Figure 1) is also proper hydration of both, your whole body and - maybe in this particular case even more importantly - your scalp! The latter may easily dry out in response to the use of inappropriate shampoos and/or hair styling products! As far as the former is concerned, there's, by the way, an interesting rodent study showing highly beneficial effects of mineral-rich spring water in SKH-1 hairless mice who are almost non-response to conventional treatment with (e.g.) minoxidil (Begum 2017).

Can you wash your hair too often? No, but you can style them to death...

If you wash your hair thrice a day, I would start investigating OCD issues, but as far as hair loss is concerned, there's currently no evidence that washing your hair daily (or even more frequently) would trigger hair loss - assuming you use a pH neutral (non-alkaline) shampoo, ideally without sulfates, that won't dry out your scalp (more about shampoos in Draelos 2010).
Caffeine penetrates the skin and open follicles are important for the time-course of penetration, human study shows putting caffeine shampoo right on the skin of hairy chests for 2 minutes (Otberg 2007).
Caffeine-based anti-hair-loss shampoos!? In case you've previously tried caffeine-based shampoos to no avail, you will also be interested to hear that you probably didn't leave them on/in your hair long enough.

If you look at the absorption data from Otberg et al. (2007 | figure on the left) it becomes clear that the absorption is significant, however, it occurred when the scientists smeared the caffeine shampoo right onto the skin and left it there for 2 minutes. Moreover, anything that would seal the follicles (like too much sebum) would at least slow down, if not impair the absorption kinetics.
What you do want to avoid, though, are (almost) boiling hot water, using a really hot hair-dryer, and - mostly for women and hipsters - tieing your strands back so tightly that they will pull on your skin and (ab)using so much hair gel, hairspray and other stuff that's keeping your scalp from breathing that your hair follicles are suffocating.

No hot water, no hot hair-dryers, no hair pulling hair hairdos - check ✓

Speaking of suffocating, while the previously mentioned ketoconazole 2% shampoo seems to have some independent anti-inflammatory effects on the dermis beneath your more or less full scalp hair, it does also kill  Malassezia spp. and Staphylococcus spp., both examples of fungi, and bacteria which are (naturally) growing on your skin, and have both been implicated in the induction of the micro-inflammatory processes that are at the heart of several types of male/female hair loss (Pierard-Franchimont 1998; Gaber 2015).
Table 4: Contrary to some claims you may have read online, anti-dandruff shampoos prevent/reduce hair loss and don't promote them. In that, the more expensive ketoconazole shampoos (Nizoral) are slightly more effective than the cheap zinc pyithione (Head & Shoulders) based products (Piérard‐Franchimont 2002)
The influence of the microbiome is yet not just restricted to local effects. In fact, studies like Nair et al. (2017) indicate that calming down the pro-inflammatory effects of the microbiome with a broad-spectrum antibiotic cocktail (ampicillin, neomycin, metronidozole, vancomycin) protects mice from autoimmune alopecia. If it's just the previously mentioned Staphylococcus species that are a problem is yet still a matter of ongoing research and, as in other related areas, the whole "microbiome and hair loss"-research is still pretty much in its infancy - and that's despite papers such as Chen, et al. (2016) which claim that "[t]he gut microbiome is required for the development of alopecia areata" as early as in their title.
Table 5: Plants commonly used in herbal shampoos (Arora 2011).
Before this research is not available you may want to look into ditching your chemically loaded P&G + Co. shampoos with natural ingredients as they have been listed in a recently published review by Arora et al. (2011 | see Table 5) - don't assume, though, that those are natural and hence without potential side effects; as far as their allergenicity are concerned some may even be worse than the "chemicals" in commercial shampoos.

Moreover, many of the commercially available "herbal shampoos" are everything but exclusively herbal-based. In fact, some of them even contain particularly unhealthy substances such as...
  • sodium lauryl sulphate and related compounds - SAS is one of the most commonly used detergent. While it is recognized as Generally Recognized As Safe (GRAS), a study done at the Medical College of Georgia has shown that shampoos with SLS could retard healing of wounds in surface of cornea and can cause cataract in adults. Furthermore, SLS will build up in heart, liver, lungs and brain can cause major problem in these areas - to this ends, it does yet have to be ingested in significant amounts. Similar effects have been observed for other sulphate-containing groups (Chiu 2015).

    Skin contact to SAS will lead to generally less severe side effects such as flaky, rough skin roughness and - you almost guessed it - corroded hair follicles with an impaired ability to grow hair. Decyl polyglucoside may be a viable alternative (Vozmediano 2000).
  • cocamidopropyl betaine -  While it is often used in ‘no tears shampoos’ for children, it seems to be responsible for many of the allergic reactions in response to both shampoos and shower gels - especially in kids (Militello 2006). 
  • diethanolamine or DEA - While DEA including the formerly widely used cocamide DEA seems to disappear from the market slowly, it is sill used in many shampoos - probably because it is still considered GRAS (offically), despite the fact that, in laboratory experiments, exposure to high doses of DEA-related ingredients has been shown to cause liver cancers and recancerous changes in skin and thyroid, as well as to "cause mild to moderate skin and eye irritation" (Udebuani 2015) - you shouldn't forget the qualifier "in high doses", though.
  • disodium ethylenediamine tetraacetic acid (EDTA) - Has mostly case reports to support its allergic potential. If you react with dermatitis to a shampoo, it may still be worth checking the label for the acronym "EDTA".
  • formaldehyde and formaldehyde releasing substances (also disguised as Quaternium – 15) - Is another potential allergenic substance that has long been one of the favorite preservatives of the average shampoo producer, because it has the nice side effect of altering hair keratin to reduce the frizziness and give a smoothness effect. Unfortunately, formaldehyde is a known carcinogen, which can cause allergic reactions of skin, eye and nose irritation, and lung cancer during dermal exposure (Chiu 2015).
  • parabens - Methylparabens and propylparabens are the most common preservatives found in the cosmetic industries that are used to control microbial growth to extend the shelf life... and they accumulate in cancerous breast tissue (Chiu 2015) - coincidence? Well, let's say that almost all major consumer good brands have either already pulled it from their formulas or are about to do that very soon. Smart move, 'cause research indicates that their bioavailability is probably higher when applied topical vs. being ingested orally.
  • polyethylene glycol (PEG) - Is, just like parabens, one of the substances producers even use to market their products... as "PEG-free", obviously. Just like parabens PEG is absorbed through intact skin and demonstrated penetration of substances across biological barriers; it can alter and reduce the skin’s natural moisture factor causing accelerated aging as well as increasing permeability of substances including harmful ingredients. As Chiu et al. point out, though, that ...
    "[...a]part from the potential concerns, there are no sufficient evidence showing systemic toxicity of acute dermal exposure [accordingly, from] the safety assessment, PEG is considered safe for use in personal care products, but there has been concerns with the contamination of 1,4-dioxane and ethylene oxide during the manufacturing process" (Chiu 2015).
    Said 1,4-doixane is, as you probably guessed it, another carcinogen, and ethylene oxide is classified as a developmental neurotoxicant. Ever since the Organic Consumers Association have found traces of contaminations in the PEG containing hygiene products - ever since, producers are pulling PEGs from their products
  • phthalates and silicon - While phthalates have been shown to possess developmental and reproductive toxicity and hormonal disturbances particularly in males (Heudorf 2007), the "wise" FDA does not recognize that phthalates pose a safety risk. The same goes for silicones such as dimethicone, where the scientific data on its toxicity is allegedly less convincing than for phthalates and many of the previously mentioned agents.
If you cannot find a shampoo without any of these (for "cosmetics", in general, the list can be extended endlessly, by the way, but those appear to be the major culprits in shampoos), you can simply use the info from Table 5 to produce your own hair care products... ok, I know, "too inconvenient" - in that our hair care choices mirror our dietary choices, where we also gravitate towards convenient, cheap products even though, by now, we should know that this won't just support the food industry, but also and even more so the pharma companies that produce and sell drugs to battle metabolic syndrome we develop in response to these foods :-/
#SVClassic: Hair Loss: Finasteride, Laser Light or Minoxidil - What Will Really Help Men & Women Regrow Lost Scalp Hair? | more
Ok, I am "eating healthy", still losing hair - What can I do? If you have the previously mentioned 'dietary ducks' in a row, there are a handful of specialty supplements with (usually sponsored) scientific backup. Zanzottera et al (2017), for example, describe a fatty acid + phytosterol supplement that prevents hair loss and promotes hair health in both women and men. The product comes in gel-caps and contains borage, linseed, wheat germ (all three >25 and <50%), and saw palmetto (>10 and <25%) as well as phytosterols (0.5-5%) from pine and rye extract. A brief look at the photos in the corresponding paper does yet show IMHO disappointing results (those I wouldn't be willing to pay for).

Rather than to waste time and money on these or related products, it would thus make sense to revisit my previous article on actually proven (but in all cases less convenient) treatment modalities such as the previously mentioned daily application of minoxidil (in dry hair!) and/or the regular use of LLLT... or coffee! Seriously, only recently Alonso and Anesi published a study showing that a spray that applies a coffee extract (+Larrea divaricata) locally can help with both hair loss and dandruff (Alonso 2018) - don't forget you got to keep it on for >2 minutes, though. Ah... and it may also help that each cup of coffee you use to rinse your hair is a cup less you'll drink and thus risk impairing the absorption of iron from your diet. Low iron is, after all, one of the #1 reasons women, especially women who don't live within the iron-fortified cereal world of North America (iron deficiency < 10% vs. 40%-60% in Africa, Asia and the Eastern Mediterranean | Stoltzfus 2003) or exercise regularly (among women with >3h of mostly aerobic work per week ~30% are deficient | Sinclair 2015), tend to lose hair | Comment on Facebook!
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