Means of individual hair counts over a 6-day period (initial counts plus subsequent 6-month counts) for subjects aged 20 through 40 years.
Means of individual hair counts over a 6-day period (initial counts plus subsequent 6-month counts) for subjects aged 41 through 60 years.
Wasko CA, Mackley CL, Sperling LC, Mauger D, Miller JJ. Standardizing the 60-Second Hair Count. Arch Dermatol. 2008;144(6):759-762. doi:10.1001/archderm.144.6.759
To define the range of normal for a standardized 60-second hair count in men without alopecia.
The study included 60 healthy men (age range, 20-60 years) without evidence of alopecia.
Main Outcome Measure
Range of normal for a standardized 60-second hair count.
Among the 20- through 40-year-old men, the shedding range was 0 to 78 hairs, with a mean of 10.2 hairs. Among the 41- through 60-year-old men, the range was 0-43 hairs, with a mean of 10.3 hairs. Low intrapatient variability for hair counts was found in both age groups, indicating consistent results on consecutive days for all participants. When repeated 6 months later in both age groups, the hair counts did not change much. The hair counts were repeated and verified by a trained investigator, with results similar to those of subject hair counts.
A properly performed 60-second hair count is a simple, practical, and reliable tool for the assessment of hair shedding.
Currently, there is no widely accepted or standard method for assessing the number of hairs shed daily. Although the dermatology literature and the media often mention that shedding of approximately 100 hairs a day is normal, that number is questionable.1 The number 100 is a theoretical, mathematical derivation based on the assumption that the average scalp contains 100 000 hairs, 10% of which are in the telogen phase: 100 000 hairs × 10% telogen hairs = 10 000 telogen hairs; therefore, 10 000 telogen hairs/100 days (average length of telogen phase) = 100 telogen shed hairs per day. Does 100 shed hairs pertain to both men and women? Does shedding remain constant with age? No clinical study or standardized method has validated the number 100.
The daily hair count and wash test are not practical methods for monitoring hair shedding over a 24-hour period. Keeping a daily total count of hairs shed is cumbersome for the patient and may yield inaccurate results because numerous hairs escape detection.2- 4 The wash test involves washing the patient's hair over a sink with a covered drain 5 days after the last shampoo. The number of washed-out hairs is then counted.2,4 Patients may be reluctant to leave their hair unwashed for 5 days. Moreover, there is no currently accepted normal range for this method, with estimates of “normalcy” ranging from 105 to 250.2,6
A more practical method for determining the number of shed hair is the 60-second hair count. Using this technique, Kligman7 attempted to establish a standard range for the procedure using 24 healthy white men aged 21 to 42 years. He found the average number of shed hairs to be 44 per interval, with a range of 15 to 75 (SD, 18). The small sample population and the lack of detail regarding the study protocol limit the applicability and interpretation of Kligman's data.
In our study, using the 60-second hair count, we expanded on Kligman's work by determining hair counts in 60 healthy white men ranging in age from 20 through 60 years. By studying a broader age range, we sought to evaluate the normal changes in scalp hair that accompany aging. These changes include a decrease in the duration of anagen (lifespan of the hair), an increased latency period between telogen and a new anagen, and a decrease in hair shaft diameter.8 Also, each subject performed the 60-second hair count on 2 separate occasions, separated by at least 6 months, to account for any seasonal differences in hair shedding.9
The study was reviewed and accepted by the institutional review board of Pennsylvania College of Medicine, Hershey. Sixty white subjects (59 with straight hair and 1 with curly hair) were recruited for the study. Thirty of the participants were aged 20 through 40 years, and the other 30 were aged 41 through 60 years. Subjects were recruited from our local community and our medical center. Inclusion criteria did not specify a specific ethnicity or race; however, based on the population demographics of the community, only white men presented for inclusion in the study. Eligible subjects included men who had no signs or symptoms of hair loss and those who did not have thyroid disease, anemia, or a history of cancer. The study also included subjects who had not begun taking certain medications (β-blockers, statins, or angiotensin-converting enzyme inhibitors) within the 6 months before testing. Each subject was examined by a member of the investigating team for signs of hair loss, and only subjects with Norwood-Hamilton stage I were eligible for participation. The subjects were issued identical combs (Cleopatra 400; Krest Combs, Leominster, Massachusetts) to be used throughout the study. The teeth of the comb, which was 15 cm long, were separated by 1 mm on one half of the comb and by 2 mm on the other half. The subjects used a shampoo (T/Sal; Neutrogena Corp, Los Angeles, California) once daily for 3 consecutive days in the morning. On the fourth day, they were instructed to comb their hair for 60 seconds before shampooing in the morning, starting at the vertex and combing forward. The hair was combed over a towel or pillowcase of contrasting color so that any shed hairs could be adequately visualized. The subjects then collected the shed hairs and recorded their number. This “comb-and-count” technique was repeated on 3 consecutive days. The subjects returned all hairs and data sheets to the investigators. The hairs were then mounted on glass slides and examined using light microscopy for the purpose of verifying the hair counts. Broken or fragmented hairs were discounted. The subjects were reexamined after 6 months for any new onset of hair loss and, if still eligible, instructed to repeat the entire procedure exactly as before. Subsequent verification of the new hair counts was performed as described above.
The average age of subjects in the 2 groups was 27.8 years (n = 30; age range, 20-40 years) and 49.4 (n = 27; age range, 41-60 years). Three subjects in the 41- through 60-year-old group were unavailable for follow-up. Figure 1 depicts the means of the individual hair counts over a 6-day period (initial counts plus subsequent 6-month counts) for subjects aged 20 through 40 years. Subjects shed an average of 10.2 hairs (range, 0-78 hairs). There was minimal intrapatient variability in hair counts over the 6-month period, indicating that the subjects were consistent in hair counts (data not shown). Figure 2 shows the means of the individual hair counts for subjects aged 41 through 60 years. The patients shed an average of 10.3 hairs (range, 0-43 hairs). As was the case with the younger age group, intrapatient daily variability in hair counts was low. Investigator hair counts were similar to subject hair counts, with an average shed count of 8.9 hairs (range, 0-64 hairs) for subjects aged 20 through 40 and 10.6 hairs (range, 0-52 hairs) for subjects aged 41 through 60 years. For both age groups, the data on the subsequent hair counts, performed 6 months later, including subject and investigator hair counts, are included in the data reported above (reflected in Figure 1 and Figure 2 as counts over a 6-day period).
This study establishes a normal range for the 60-second hair count in men aged 20 through 60 years who have clinically normal scalps. Our hair counts of approximately 10 for both age groups are lower than the average hair count of 44 predicted by Kligman.7 We suspect that this difference is most likely attributable to hair count technique, which was not clearly defined by Kligman. Another factor that may have contributed to lower than expected values for numbers of hair shed may be the study's requirement of daily shampoos on the 3 days immediately preceding the hair counts. It is possible that this requirement represents an artificially high frequency of hair washing, which, in turn, may cause the number of hairs shed on subsequent days to be lower than that which would be expected with less frequent shampooing.
Ranges and mean values for hair shedding did not differ significantly between the younger (20-40 years old) and older (41-60 years old) age groups (mean P = .60; range P = .24). Although not statistically significant, the slightly lower overall range that was seen in the older population may indeed more closely represent a normal range for hair shedding, as older men without any evidence of alopecia are presumably less likely to progress to significant hair loss than their younger counterparts. It is interesting to note the rather high value of the upper end of normal in the younger age group; the question arises as to whether evaluating the participants who fall within the higher range beyond the 6 months of this study would yield similar results or whether these individuals are in the early stages of telogen effluvium or androgenetic alopecia.
Studies have suggested that involutional alopecia, the natural thinning of hair with age, does not appear to be associated with increased shedding of hairs. The number of scalp hairs decreases (25-35 hairs vs the normal 35-45 hairs in 4-mm punch biopsy specimens), but there is a normal proportion of telogen hairs (approximately 20%).10,11 To answer this question with certainty, subjects would need to be followed up over time using the 60-second hair count.
As can be seen in Figure 1 and Figure 2, there is a broad range for normal values of hair shedding during a 60-second hair count. Normal percentages of telogen hairs may range considerably (0%-25%, with an average of 13% in one study and an average of 6% in another study).5,7 This variability may account for the range of normal with the 60-second hair count. Low intrapatient variability in hair counts, as well as consistency between investigator and subject hair counts, make the 60-second hair count an objective and practical tool for monitoring hair shedding. Low intrapatient variability indicates easily reproducible results on consecutive days. If a patient presents with an acute telogen effluvium, the dermatologist can instruct him or her regarding the 60-second hair count. The technique comprises the following 4 steps:
Before shampooing, comb your hair for 60 seconds over a pillow or sheet of contrasting color to your hair, starting with the comb at the back top of the scalp and moving the comb forward to the front of the scalp.
Repeat the procedure before 3 consecutive shampooings (eg, if you shampoo every other day, then repeat the procedure every other day), and always use the same comb or brush.
Count the number of hairs in the comb or brush and on the pillow after each hair count and record.
Repeat the above procedure monthly and bring the results to your next dermatology visit so you can review them with your dermatologist.
The counts are performed monthly, and the patient returns in 6 months with the average number of hairs shed during each month. It is important to note that although the 60-second hair count in this patient population cannot adequately measure the number of hairs shed from the lateral and posterior portions of the scalp, the technique provides a simple, easy-to-use tool for quantifying and tracking a patient's hair loss. Patients willingly perform the hair counts so that they can gain some control over a condition in which they feel that they have no control.
Study limitations include the inability to generalize our findings to persons of all ethnicities. Our study was almost exclusively limited to white men with straight hair (1 man had curly hair). Previous studies have documented decreased hair density in African Americans compared with whites.12 Hair density could influence the amount of hair shedding in a 60-second timed hair count. With 1 exception, subjects with curly hair and long hair were not studied because of the difficulty of running a comb through the hair, which would lead to increased numbers of broken hairs, thereby falsely elevating hair counts. Differences in the spacing of the teeth of the comb could yield different hair counts, and the comb used in our study has wider teeth on one half and smaller teeth on the other half. In future studies, we recommend using combs with teeth of similar size and spacing. Future studies should aim to include larger number of participants as well as to compare different values of normal in different ethnicities. Furthermore, additional studies comparing our results with those obtained from patients with androgenetic alopecia or telogen effluvium would undoubtedly increase the usefulness of this technique.
In summary, the 60-second hair count is a simple, practical, and objective tool for monitoring conditions associated with hair shedding. Low intrapatient variability demonstrates that dependable results over an extended period of time are obtainable. The similarity between investigator and subject hair counts indicates that patients can reliably count hairs. Studies of the 60-second hair count in normal women and in the setting of hair disease still need to be performed.
Correspondence: Jeffrey J. Miller, MD, Department of Dermatology, Penn State College of Medicine, UPCII, Ste 4300, 500 University Dr, Hershey, PA 17033 (firstname.lastname@example.org).
Author Contributions: Dr Miller had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. Study concept and design: Wasko, Mackley, Sperling, and Miller. Acquisition of data: Wasko and Mauger. Analysis and interpretation of data: Wasko, Mauger, and Miller. Drafting of the manuscript: Wasko, Mauger, and Miller. Critical revision of the manuscript for important intellectual content: Wasko, Mackley, Sperling, and Miller. Statistical analysis: Mauger. Administrative, technical, and material support: Wasko. Study supervision: Miller.
Financial Disclosure: Dr Miller is a consultant for and has received honoraria from Pfizer Inc.
Funding/Support: This study was supported by a study grant from Merck.
Role of the Sponsor: The sponsors had no influence on the acquisition, interpretation, or publication of the study.