370 JOURNAL OF COSMETIC SCIENCE called catagen to an active growing state called anagen (4). When hair emerges into the anagen phase, it begins to change its physical appearance from small colorless fibers called vellus hairs to thick hair that contains color called terminal hairs (1). Testosterone breaks down in the human body principally via action of an enzyme called 5-a-reductase which converts testosterone into 5-a-dihydrotestosterone (DHT) (5-7). Dihydrotestosterone is also a powerful androgen which binds to the androgen receptor. Typically, for most people, this binding of dihydrotestosterone is reversible and does not interfere with the anagen growth of the hair. However, for some individuals (men and women), the binding of dihydrotestosterone begins to dominate the steroidal cycle and the hair follicles are driven out of anagen phase and into telogen and catagen phase. Subsequently, the terminal hair fibers shrink and lose their color. This leads to a condition known as alopecia or baldness (8). The exact biochemical and genetic reasons for this situation are not presently known, although considerable research is being conducted to better understand the reasons why some people lose their hair and others do not. However, it stands to reason that in order to influence the strength of a hair fiber, it would be necessary to try and do this at the point in which the hair is still living. In this regard, a shift in treatment perspective is required and instead of looking at how to improve the structure of the dead hair fiber, might it be possible to influence the fiber integrity at earlier stages of growth while it is still within the confines of the follicle? In addition, the definition of hair strength must also be renewed as improving hair fiber strength means something entirely different if one is talking about keeping the hair fiber from being extracted, intact, from the follicle. In a normal human being with non- alopecia hair, the head will typically lose nearly 100 hairs a day through normal exfo- liation processes (2). This level is grossly increased due to a number of situations such as alopecia, damage of the hair fibers, or attempts to comb the hair when it is wet and tangled. While some have argued that hair fibers do not simply break by elongation, but rather through interaction with other fibers that become entangled and crossed on the tangs of the brush or comb, it must be fundamentally understood what force is greater for apparent hair loss, hair breakage or hair extraction (9, 10). This paper will attempt to address these inconsistencies by looking at hair fiber health via well established skin care treatment practices. METHODS TREATMENT INGREDIENTS For this study, a hair treatment composition which comprises the following ingredients at the ratios shown was developed (Table I). CONDITIONER COMPOSITION A commercially available, silicone-free conditioner was used throughout the study. To the commercial conditioner was added 5% of the composition shown above to create the "Active" formulation. The conditioner with additional water equal to the amount of water added to the active formulation was used as the "Placebo."

2006 TRI/PRINCETON CONFERENCE Ingredient (INCI name) Water Hexapeptide-11 Fruit acids Betaine Green tea polyphenols Hexylene glycol IN VIVO TESTING PROTOCOL Table I Treatment Ingredients Percentage in composition 46-50 1-2 25-30 8-12 2-3 8-12 371 The entire study was conducted at a clinically-sponsored salon which the participants visited every day for five days. Prior to commencing the study, the participants signed informed consent agreements. Participants were all Caucasian women with a mixed population of damaged and non-damaged hair, between the ages of 30 and 60, of general good health and non-pregnant. Each participant was required to have hair of at least 12 inches in length. None of the participants reported signs of female alopecia or other known scalp conditions which might skew the test results. Prior to commencing the study, the participants went through a five day wash out period on their hair using a simple ionic shampoo and the placebo conditioner. In addition, after the wash-out period, but prior to the treatment period, each participant had a fabric collar transfixed around their neck so that during drying, any hairs which fell from the head were captured in the collar. The participant's hair on one half of their head (to remain consistent with the test results from the half-head study described below) was then dried for three minutes with a brush and a 1200 W hair dryer. At the end of the drying period, the clinician then gathered all of the hair fibers that were trapped in the brush and those that had fallen into the collar and these hair fibers were culled into plastic bags and labeled as "Day O." Only fibers that could be visibly seen were gathered (typically greater than ½-inch in length or greater). The participants came into the salon every day at the same time for their hair treatments. During the treatment, each participant was shampooed with the same simple shampoo and then the hair was combed to afford half-head treatment sites. To one side of the head, the salon clinician applied the placebo conditioner and allowed the conditioner to reside on the head for five minutes prior to rinsing. To the other side of the head, the participants were treated with the conditioner containing the active ingredients which were also allowed to reside on the scalp and hair for five minutes prior to rinsing. Each side of the hair was rinsed in such a way as to prevent treatment from one side of the head to wash over to the other side of the head. Such treatments were continued once a day for five complete days. At completion of the study period, after the final conditioning rinse, the participants were affixed with the same collar mentioned above and each side of the head was dried for three minutes. After completion of one side of the head, all the hair fibers were gathered before the other side of the head was similarly dried. The hair fibers were culled as before and placed into plastic Ziploc bags and labeled as "Day 5" with identification of whether they were from the active- or placebo-treated side of the head.