In the bbc series the singing detective, the protagonist suffers from terrible psoriasis.
At one point, a well-meaning orderly tells him in a conspiratorial whisper, "It's the tomahtoes! Don't eat the tomahtoes! I'm tellin' ya." And we think, oh, how silly. Well, there may actually be something in that. Fact is, nobody knows what causes psoriasis, a lifelong non-contagious skin disease, or how to cure it. It can affect small areas of the body or spread massively, causing joint inflammation and related arthritis.
One common and effective treatment everyone seems to agree on is light therapy using UV-B rays. And stress, though an over-cited cause for just about anything, also shows up as a consensus issue here.
Beyond that, you'll find endless treatment suggestions online, from acupuncture to salt water, and from magnetic therapy to topical applications of evening primrose and emu oils and apple cider vinegar.
How to wade through all this stuff to find out what actually works?
What the experts say
"Psoriasis is your body's attempt to expel through the skin things that are unwanted or harmful. [Your health] would be much worse if those things weren't released. Psoriasis also has to do with the emotions. Your skin is the boundary between you and the outside world. Often, when there is conflict there, you get skin problems. We get skin problems when our boundaries are too hard. There is often a strong stress component to skin issues. They are also often associated with food sensitivities. I use acupuncture and counselling ."
KALEB MONTGOMERY , Chinese medicine practitioner, Toronto
"Stay away from combinations of fruits and dairy, particularly fruit and yogurt. The combination is too acidic. Don't overindulge in citrus fruits and tomatoes or yeast-producing things like beer and red wine. We treat stress and poor diet and then recommend internal herbs. We might cook sesame seed oil with organically grown neem to make an excellent ointment. An essential oil formula, a combination of lavender , frankincense , ravensara , geranium and myrrh , used topically aids healing and itching. Don't wear nylon clothes."
ANDREA OLIVERA , Ayurvedic practitioner, Toronto
"What was happening when the psoriasis began? You must treat that. Was the person on any medications or antibiotics or experiencing an emotional upset? Look for gut-derived toxins such as [those produced by an overgrowth] of candida albecans. Increasing fibre in the diet promotes their excretion. Supplementing with probiotics balances the gut flora. Take freshly ground flaxseeds or fish oils , and don't drink alcohol. Drink the juice of half a lemon squeezed into 8 ounces of water to help detoxify the liver. Supplement with milk thistle . Eliminate wheat, sugar and caffeine and animal products like milk, cream and red meat. Tomatoes and peppers are common food sensitivities. Limit anything that will increase cell proliferation like vitamin C, biotin, ginseng and echinacea. Vitamin A and zinc are good. Oatmeal baths and topical applications of red clover or aloe vera can soothe."
KERRI LYNN LAPOINTE , naturopath, Toronto
"The most common herb in psoriasis formulas is fumitory , known for the chemical constituent fumaric acid. I've had good luck with chaparral , which contains a chemical called NDGA that is supposed to help clean the liver and clear the skin. Some studies suggested it had role in liver damage, but FDA trials showed this to be a mistake. I use a lot of figwort , but some people are allergic to it. Herbs for the liver like burdock , dandelion and milk thistle are vaguely related to the goldenrod family and could aggravate the conditions of people with dermatological allergies. Neem is good, as is calendula rubbed in topically. I've had good results with patients taking vitamin D in high doses."
ROGER LEWIS , chartered herbalist, Toronto
"Topical treatments include corticosteroids , Dovonex (a vitamin D analogue), salicylic acid and coal tar . Sometimes we use retinoids . Orally, we use retinoids or cyclosporin , an immunosuppressant medication. I was introduced to herbals when people started coming to me with reactions to them. I've seen reactions to cayenne , also called capsaicin, even though there are studies showing that it does work. I've also seen reactions to aloe, tea tree oil and chamomile.
People often think what they read on the Internet is true, but you have to know the potential side effects [of herbs] as you do for other medications. Aloe vera, for example, is very good but has been shown to have a photo-reaction, meaning sun exposure can cause an allergy to topical aloe. The alternative treatments that do work are cayenne , aloe, shark cartilage and dong quai . But again, you really have to know about possible interactions. One that definitely doesn't work is evening primrose."
SHARON JACOBS , assistant professor, clinical dermatology, University of Miami, Miami, Florida