56 JOURNAL OF COSMETIC SCIENCE Table I Hair Length Survey: US Women--Hair Length and Age (Nov./Dec. 1972)(10) Hair length/Age groups 14 to 24 25 to 34 35 to 50 50 to 60 14 to 60 Short 11% 27% 34% 53% 33% Medium 45% 40% 52% 38% 43% Long 44% 33% 14% 10% 24% Number of panelists 512 518 664 706 2400 Short = chin-length or shorter. Medium = chin-to-shoulder length. Long = shoulder-length or longer. 40 percent of men and 10 percent of women (a bit higher after menopause) (11) and interferes with one's ability to grow long hair. Several congenital disorders weaken hair fibers, leading to greater than normal breakage, and thus limit the length that hair fibers can attain. Trichorrhexis nodosa, monilethrix, and pill torti are such ailments. Other disorders such as alopecia and telogen effluvium also interfere with hair growth and thus limit the length that hair can attain. A few medications such as streptomycin, cyclosporin, diazoxide, spironolactone and estrogens can lengthen anagen, thus producing longer and thicker hairs. On the other hand, most chemotherapy agents shorten anagen, producing a temporary balding con- dition. The condition of the Guinness long-hair titleholders is another disorder that increases the timespan of anagen, most likely involving the hormone testosterone. Minoxidil and finasteride, two medications developed for other purposes, were found in early clinical studies to produce long terminal hair growth as a side effect. These drugs are now being sold by Upjohn and Merck, respectively, either to help prevent hair loss or to grow hair for persons concerned with baldness. Hair cutting and hair length. Hairstyles and hair cutting are related to societal trends and our perception of beauty. Thus, psychological factors are very important to hair length, because the hairstyle that we select determines the length that we choose to cut our hair, and how we cut our hair is probably the most important factor that determines hair length for most persons today. Hair damage/breakage and hair length. For long hair and for very curly to kinky hair, breakage can be an important factor affecting hair length. Some of the primary causes of hair breakage are chemical treatments of hair and how curly the hair is, coupled with how we wash and comb it or brush it out. Bleaches, permanent waves, and hair straight- eners do damage hair. However, when these treatments are applied properly, they should not produce significant breakage. When these treatments are not applied properly or when combinations of these treatments are used, significant breakage can occur. Extremely curly or "kinky" hair is often very oval-shaped and behaves more like fragile, fine hair. Excessive tangling can occur with kinky hair and high combing forces are encountered. Therefore, extreme care must be taken to derangle or to minimize aletan- gling of this type of hair or excessive breakage will occur. As a consequence, long, very curly hair from African-Americans (12 inches or longer) is almost impossible to purchase in bulk from hair dealers, but Caucasian or Oriental hair 12 to 24 inches in length is rather easy to obtain. Thus, a great deal of experimental research for very curly or kinky

HAIR LENGTH IN THE USA 57 hair (long) is done with either Caucasian or Oriental hair that is steam set in a curly/ kinky configuration. Care must also be exercised in straightening hair from African- Americans or damage from straightening can lead to hair breakage. Wearing hair in dredlocks or long braids significantly reduces the amount of detangling for very curly hair and, as a result, can lead to less breakage and thus allow longer hair to be achieved for those with very curly hair. Combing/brushing forces also increase with hair length. Therefore, very good condi- tioners and shampoos must be used for long hair, along with special combs and combing techniques. Extra time for washing and for combing the hair out must also be allowed or breakage will result. A statement about Diane Witt (a Guinness long-hair record holder for 1988 and 1990) who had hair more than 300 centimeters long (nearly 10 feet long), indicating that she required an entire day to wash and comb her hair out, confirms these conclusions (www.guinness.terrashare.com/diane-witt/geo.htm). HAIR LENGTH FROM CONSUMER RESEARCH AND OUR STUDIES Many companies involved in selling hair products to consumers conduct surveys that sometimes include questions on hair length. These surveys usually categorize hair length as in Table I: short hair = chin-length or shorter medium-length hair = chin-length to shoulder-length long hair -- shoulder-length or longer. Larger consumer products companies generally do not subdivide long hair into addi- tional categories, even though it would be easy to do. Smaller consumer companies may sell to these small segments, but the larger companies have little interest because of the limited sales potential, especially for the waist-length or longer hair. To obtain data on the actual percentages of persons in the United States with longer hair (shoulder-length or longer), we conducted eight hair length studies in Central Florida theme parks during the period January through March of 2001. The data from these studies are summarized in Table II. We believe that the population at these theme parks represents a good random assortment of normally active adults of all ages in the US (see the next section (The population). The numbers here involved both males and females about 137 centimeters (41/2 feet) tall or taller (by visual observation). The total number of males and females in all eight studies was 24,300 persons. The total number with hair shoulder-length or longer was 3,212 or 13.2 percent of the total population. This percentage is reasonably close to the earlier consumer survey showing 24 percent of US females with hair shoulder-length or longer (Table I), approximately 12 percent of the total population. The total number in our studies with hair down to the bottom of the breast or lower rim of the shoulder blades or longer was 587 or 2.42 percent of the total. The total number with hair down to the waist or longer was 77 or 0.317 percent. Only 22 men had hair shoulder-length or longer therefore, 0.181 percent of men have hair shoulder length or longer, representing only 0.09 percent of the total population. Only three men in this total group had hair down to their waist (approximately 0.025 percent or about three in 10,000). One of these men had very long braids (very curly hair), and I assumed (probably incorrectly) that it was his natural hair down to his waist and included him in the count. For the very longest hair, only four people (all women) were observed among the 24,300