turbo-1 said:
I used to buy Head and Shoulders, years back, until I discovered that if I wash my hair with really mild, simple shampoo/soap, the dandruff would go away all by itself. For a long time, I used No More Tears baby shampoo (which we also used to bathe our ferrets), but Scent-A-Way hunter's soap is cheaper and lasts much longer, and is a good all-body soap.
Turbo's right. The main cause of dandruff is drying your scalp out by using too much shampoo, way too often.
That's why you really shouldn't wash your dog more than once a month. You're washing away protective oils that cause the skin to dry out, causing dandruff, etc.
The problem with humans is that walking around with all of those protective oils in your hair makes you look like some kind of geeky slob. People like it even less if you're one of those lumber jack types, since you'll probably also accumulate dirt, leaves, wood chips, twigs, bugs, small birds, etc.
Ideally, the shampoo you use is mild enough to wash away all miscellaneous debris, plus some of those protective oils without drying out your scalp. A milder, baby shampoo is often enough. If you're spending a lot of time outdoors, wearing a hat might make a dandruff shampoo unnecessary, since the Sun tends to dry out your scalp, as well. Sometimes you have to use a medicated shampoo to find a non-greasy balance.
Other than finding something fairly gentle, look for something cheap or something that smells fairly nice (unless you're female, in which case something that smells very nice is sometimes acceptable).
On the other hand, turbo's recommendations for shaving cream is horrible. I stuck a bar of soap in my hot lather machine, but nothing would come out the spout when I pushed the button no matter how long I left the soap in there.
I don't know of independent shampoo tests, but independent tests of laundry detergents are surprising. Clothes washed in plain water usually get an average rating in a comparison where the top to bottom ratings are practically random (in other words, you never get a consistent winner in different comparisons). Laundry detergent gets rid of heavy dirt and grease very effectively - except most people in office type jobs don't get enough dirt or grease in their clothes for laundry detergent to really matter.
There is an exception. Detergents with extra ingredients that interact with ultraviolet light get higher ratings, provided you follow the directions and use more than can possibly rinse out - your clothes will appear brighter, especially under black lights. Of course, if you follow the directions on laundry detergent bottles, your clothes will still have detergent left in the fibers while you're wearing them, so you'll need a fabric softener to counteract the stiffness caused by excess detergent. Now, that's a scam.
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You have to put in a bar of hard soap AND a boar-bristle brush! People just don't follow directions!
