COSMETIC AND AMINO ACID ANALYSIS OF HAIR 295 A similar analysis of the data for lysine content found that there were statistically sig- nifi cant (p 0.10) decreases after relaxer treatment: 2.0 [1.5–2.3], p = 0.082 and 2.0 [1.5–2.2], p = 0.036 for the lye and no-lye, respectively, compared to the virgin hair [2.1 (2.0–2.6)]. However, the difference between the decreases for the two relaxer types was not statistically signifi cant (p = 0.920). Interestingly, lysine has been reported to be used as a treatment for hair loss (14). Changes observed for the other 15 amino acids analyzed in this study were found not to be statistically signifi cant (p 0.10) for either relaxer treatment. CONCLUSIONS The no-lye relaxer performed better than the lye relaxer with regard to hair straightness. The former also appeared to perform better overall with regard to other hair quality pa- rameters such as dryness, softness, and shininess in addition to appearing to be milder on the scalp. There was consistency between the fi ndings of the two parts of the study: in- creased straightness was accompanied by decreased cystine content. More research needs to be done on the no-lye relaxer because of its overall better clinical performance. The authors intend to repeat the study with a larger group of subjects. ACKNOWLEDGMENTS This work was partially fi nanced by the National Research Foundation of South Africa (NRF THRIP grant no. TP2006060900011) and the industry partner AMKA Products Table VI Cystine Content (g/100 g hair) of the Hair Samples (Mean Values, n = 2) After treatment Subject no. Before treatment Product A (Lye) Product B (No-lye) 1 11.9 7.8 3.9 2 10.7 8.5 4.8 3 9.1 9.9 4 4 8.7 2.5 2.9 5 6.7 4.9 4.6 Median [range] 9.1 [6.7–11.9] 7.8 [2.5–9.9] 4.0 [2.9–4.8] Table VII Statistical Analysis of Cystine Data Group (n = 5) Groups compared p-value CL (%) Before treatment (BT BT vs. L 0.086 (p 0.1 90 After lye treatment (L) BT vs. N 0.005 (p 0.01) 99 After no-lye treatment (N) L vs. N 0.085 (p 0.1) 90

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