Chickens, toads, and gluten sensitivity

Keratosis pilarisBy: Laurie Laforest
Keratosis pilaris is one of the many symptoms attributed to non-celiac gluten sensitivity in alternative medicine circles.  Keratosis pilaris – or “chicken skin” – is a benign skin condition reminiscent of permanent goose bumps.  I first heard the term keratosis pilaris on a episode of The Dr. Oz Show about gluten sensitivity [1], the premise being that keratosis pilaris results from fat malabsorption caused by gluten-induced intestinal damage.  Since my family and I have little patches of this on our elbows and knees, I was eager to learn what was really behind it.
It turns out that the link between “chicken skin” and gluten sensitivity is one of mistaken identity.  Keratosis pilaris is a type of follicular hyperkeratosis where excess keratin – a key protein in our outer layer of skin and in our hair and nails – plugs the hair follicule, sometimes trapping a small hair inside. [2]  Enlargement of the follicule and the presence of the hard keratin plug produces the characteristic rough and bumpy appearance; reddening may also occur.  Keratosis pilaris is quite common – it affects around 50% adolescents (80% of females) and 40% of adults – and seems to have a strong hereditary component. [3]
Phrynoderma – or “toad skin” – is another type of follicular hyperkeratosis that is typically related to malnutrition in developing nations.  Phrynoderma is what alternative medicine folks are actually thinking of (or they should be) when they speak about a diet-related bumpy skin problem.  The exact nutrient deficiency behind phrynoderma is not known, but the condition can be reversed by supplementation with essential fatty acids, vitamin A, vitamin E, or B-complex vitamins; different people seem to respond to different nutrients. [4-7]
So “chicken skin” (keratosis pilaris) is common and benign, while “toad skin” (phrynoderma) is uncommon in the developed world and a sign of a serious problem.  But could it still be possible that gluten sensitivity is at the heart of these conditions?  Most likely not.  Keratosis pilaris is not related to diet, although it does seem to occur more often in people with a high body mass index. [8,9]  Hormones could also play a role, since keratosis pilaris is more common during adolescence.  Still, keratosis pilaris can come and go throughout adulthood and may worsen during the drier winter months.
Even for phrynoderma, the gluten connection doesn’t pan out.  Let’s first consider celiac disease, an autoimmune reaction triggered by gluten that damages the small intestine.  Celiac disease is the worst-case scenario when it comes to gluten sensitivity – fat malabsorption is a classic symptom of untreated celiac disease, and there is a risk that celiac sufferers could be deficient in fat-soluble vitamins like A, D, and E.  But even though it might seem like celiac disease could produce the kind of malnutrition that leads to phrynoderma, phrynoderma is not one of the skin conditions seen alongside celiac disease [10], and fat-soluble vitamin deficiencies are also not found in newly-diagnosed celiac patients as often as one is led to believe on TV [11-13].  Now consider that non-celiac gluten sensitivity is not supposed to involve the characteristic intestinal damage (and, hence, the potential vitamin deficiencies) found in celiac disease [14,15], and you have no reason for the average person to suspect that their rough skin is related to gluten.
If you do have “chicken skin” or other roughening or reddening of the skin, it is best to talk to a dermatologist to properly identify your skin condition or to your doctor if you do suspect that you have celiac disease.  Most people with keratosis pilaris don’t even realize that they have it, but others may be plagued by large, unsightly patches of skin.  Mild cases can be improved by over-the-counter moisturizers; more severe cases can be treated by medicated creams that soften keratin and help remove the outer layer of skin.  Even though there is an abundance of advice on treating keratosis pilaris on the Internet, ask a doctor or pharmacist to direct you to the right products to use.
<a rel=”author” href=”https://plus.google.com/108035110292301860932″>Laurie Laforest</a> – <a href=”http://foodconnections.org/”>foodconnections.org</a>
References
1. The 5 Hidden Signs You Have a Gluten Allergy [Internet]. The Dr. Oz Show. 2014 [cited 2014 Nov 14]. Available from: http://www.doctoroz.com/episode/5-hidden-signs-you-have-gluten-allergy
2. Hwang S, Schwartz RA. Keratosis pilaris: A common follicular hyperkeratosis. Cutis. 2008;82(3):177–80.
3. Alai AN, Elston DM. Keratosis Pilaris Treatment & Management [Internet]. Medscape. [cited 2014 Jun 12]. Available from: http://emedicine.medscape.com/article/1070651-overview
4. Ragunatha S, Kumar VJ, Murugesh SB. A Clinical Study of 125 Patients with Phrynoderma. Indian J Dermatol. 2011;56(4):389–92.
5. Bagchi K, Halder K, Chowdhury SR. The etiology of phrynoderma; histologic evidence. Am J Clin Nutr. 1959 Jun;7(3):251–8.
6. Nadiger HA. Role of vitamin E in the aetiology of phrynoderma (follicular hyperkeratosis) and its interrelationship with B-complex vitamins. Br J Nutr. 1980 Nov;44(3):211–4.
7. Therapeutic Response of Vitamin A, Vitamin B Complex, Essential Fatty Acids and Vitamin E in the Treatment of Phrynoderma: A Randomized Controlled Study. Journal of Clinical and Diagnostic Research. 2014;8(1):116–8.
8. Yosipovitch G, Mevorah B, Mashiach J, Chan YH, David M. High body mass index, dry scaly leg skin and atopic conditions are highly associated with keratosis pilaris. Dermatology (Basel). 2000;201(1):34–6.
9. Yosipovitch G, Hodak E, Vardi P, Shraga I, Karp M, Sprecher E, et al. The prevalence of cutaneous manifestations in IDDM patients and their association with diabetes risk factors and microvascular complications. Diabetes care. 1998;21(4):506–9.
10. Caproni M, Bonciolini V, D’Errico A, Antiga E, Fabbri P. Celiac Disease and Dermatologic Manifestations: Many Skin Clue to Unfold Gluten-Sensitive Enteropathy. Gastroenterology Research and Practice. 2012;2012:1–12.
11. Imam MH, Ghazzawi Y, Murray JA, Absah I. Is it Necessary to Assess for Fat Soluble Vitamin Deficiencies in Pediatric Patients With Newly Diagnosed Celiac Disease?: Journal of Pediatric Gastroenterology and Nutrition. 2014 Mar;1.
12. Villanueva J, Maranda L, Nwosu BU. Is vitamin D deficiency a feature of pediatric celiac disease? J Pediatr Endocrinol Metab. 2012;25(5-6):607–10.
13. Wierdsma NJ, van Bokhorst-de van der Schueren MAE, Berkenpas M, Mulder CJJ, van Bodegraven AA. Vitamin and Mineral Deficiencies Are Highly Prevalent in Newly Diagnosed Celiac Disease Patients. Nutrients. 2013 Sep 30;5(10):3975–92.
14. Sapone A, Bai JC, Ciacci C, Dolinsek J, Green PH, Hadjivassiliou M, et al. Spectrum of gluten-related disorders: consensus on new nomenclature and classification. BMC medicine. 2012;10(1):13.
15. Sapone A, Lammers KM, Casolaro V, Cammarota M, Giuliano MT, De Rosa M, et al. Divergence of gut permeability and mucosal immune gene expression in two gluten-associated conditions: celiac disease and gluten sensitivity. BMC Med. 2011 Mar 9;9:23.

Please don’t eat the daisies

daisiesBy: Christopher Labos MD CM FRCPC

Like most people I get most of my news by scanning the headlines and picking a few choice articles to read in depth. In general, political scandals get a pass and world events get a second look. But one day I awoke to find this headline in my Twitter feed: Eating flowers ‘could help reduce cancer risk.’

I really couldn’t let this slide.

I had to read this article if only to find out why “could help reduce cancer risk” was in quotation marks.

The article was published in the British newspaper The Telegraph and opened with this paragraph: “Eating flowers grown in British gardens could help to reduce the risk of heart disease and cancer, according to a new study.”

It made me wonder whether the chipmunks that harass my garden all summer might be on to something.

The article itself was sparse on details, so I went back to the original study, which was published in the Journal of Food Science. This is hardly a high-end medical journal, with an impact factor (how we measure the quality of medical journals) of 1.775, which is pretty underwhelming.

Already skeptical, I read on. Essentially a group of researchers measured the levels of phenols in various species of flowers and reported their antioxidant effects using a variety of chemical tests. Nowhere did the report mention cancer or heart disease, nor did they do any tests on human subjects. Clearly, the Telegraph reporter decided to editorialize a bit.

The big leap was that antioxidants must be good for you because everyone is talking about them. In fact, the clinical evidence for antioxidants is very poor.

It is true that antioxidants can neutralize free radicals. It also true that free radicals have been implicated in a number of diseases, including heart disease and cancer. But clinical trials of antioxidants have come back negative.

Vitamin A, vitamin C, vitamin E and carotenoids (all antioxidants) have been studied in large trials like the Physician’s Health study and the Women’s Health Initiative and have been found to have no benefit in preventing heart disease or cancer.

A recent Cochrane Review came to the same conclusion. Certain supplements like beta carotene have actually been seen to increase cancer risk in certain subgroups like smokers. Will phenols, the latest class of antioxidants to gain popularity, have better outcomes? We shall see; but so far the track record for antioxidants is not stellar.

Clearly, the conclusions of the newspaper account went beyond what the scientific study had reported. The danger of these types of stories is that, firstly, the public becomes misinformed. Although some flowers are edible and can be part of very appetizing dishes, some can be poisonous when ingested. Lilies, azaleas and poinsettias can cause health problems if eaten, although serious health consequences are fairly rare.

What happened here is that a study with very limited clinical applicability was given undue prominence by a British newspaper that capped it off with an eye-catching title that had little evidence to back it up.

Fortunately, most North American media outlets didn’t pick up the flower story and the National Health Service in Britain did a fairly good job of exposing the flimsy evidence behind the headline.

Although I recognize that most people are not going to start reading obscure medical journals, it is worthwhile to go beyond the headlines and read news reports all the way to the bottom. It is especially important to do so if the headline contains the word “miracle cure” or “breakthrough,” because by the end of the article you will probably realize that it is neither.

So my advice to you is not to go eat the flowers in your garden, not to go buy something simply because it has the name antioxidant on the label, and always read health related articles all the way to the bottom. For those of you who made it to the end of this article: well done.

 

Christopher Labos MD CM FRCPC

Division of Epidemiology, Biostatistics and Occupational Health

McGill University

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