EFFECT OF COCONUT OIL ON HAIR DAMAGE 177 Table II Analysis of Variance Data for Half-Head Treatments for Protein Loss Hair type Source of Degrees of Sum of F-Value at 95% variance freedom squares Mean square confidence level Normal Oil type MO Bleached Oil type MO Normal Oil type SFO Bleached Oil type SFO Normal Oil type CNO Bleached Oil type CNO Between treatments Experimental error Between treatments Experimental error Between treatments Experimental error Between treatments Experimental error Between treatments Experimental error Between treatments Experimental error 1 34.8 34.8 o.6 38 2234.6 58.8 1 42.8 42.8 1.1 38 1545.7 40.7 1 39.6 39.6 1.1 38 1345.6 35.4 1 48.6 48.6 1.5 38 1195.6 31.5 1 31.6 31.6 6.2 38 195.6 5.1 1 36.5 36.5 4.9 38 286.5 7.5 F theoretical for 1.38 degrees of freedom at 95% confidence level = 4.08. smoothness and shine. Grooming methods involving abrasive procedures are known to damage hair and its appearance. Historically, coconut oil has been used as a hair dressing in the developing countries in the tropical regions of the globe where the coconut is cultivated extensively. Prolonged use of coconut oil has been known to lead to healthy looking long hair, suggesting that it may prevent damage to the cuticle in grooming procedures involving abrasion. Obvious is the lubricating effect of oil on fiber friction, which reduces abrasive damage, especially in combing. However, in modern times, the trend in hair oil formulations is more towards the use of non-sticky oils such as mineral oil or less greasy oils such as sunflower oil. This is done primarily because of cost differentials as well as to overcome the undesirable properties of coconut oil such as greasiness, its strong smell, and freezing at ambient temperatures. This investigation is aimed at comparing the effects of these two oils along with that of coconut oil in preventing hair damage when used as a preconditioner. Although several methods involving scanning electron microscopy (SEM) measurement of combing forces and tensile mechanical properties have been used earlier to characterize hair damage, we have used protein loss and water uptake methods for this purpose. Furthermore, these methods have been extended to study the beneficial effects of these oils in preventing chemical, thermal, and UV damage. Efficacy of these methods has been established in an earlier paper from this laboratory (3). MATERIALS AND METHODS MATERIALS Samples of straight, curly, wavy and permed hair of Indian origin were used in this work. The length of the Indian hair strands was 25 cm.

178 JOURNAL OF COSMETIC SCIENCE PROTEIN LOSS IN ug/g OF HAIR 200- 160 - 120- 80- 40- i 176 173 135&116 }92 92 86 i COCONUT OIL 17 165 i SUNFLOWER COCONUT SUNFLOWER OIL OIL OIL PRE-WASH TYPES OF OILS POST-WASH IBWITHOUT EIWITH Figure 1. Comparison of protein loss from undamaged hair. The reagents for protein estimation were obtained from Sigma Chemical Co. (St. Louis, MO). The other reagents such as buffers and salts were of analytical grade, whereas the oil samples were used as they are available commercially. METHODS Sample preparatio,. Hair tresses of 3+0.5 g were prepared for this investigation. They were secured at the root end by a crochet so that they remained firmly in place, and not a single hair came out of the tress during experimentation (either because of combing or during the procedure). They were cleaned by soaking in 0.01% (w/v) of polysorbate 80 (30 min at 28øC), de-ionized water at room temperature (several rinses), and 0.01% (w/v) of acetic acid (15 min at 28øC), in that order. Finally, they were extensively rinsed in water and air dried. Bleached hair was prepared by using a bleaching kit containing 30 vol. hydrogen peroxide and ammonia solution to adjust the pH to -10. Five milliliters of this solution was used per tress (cleaned by the procedure mentioned earlier), and the treatment time was 120 min at room temperature. With this treatment the tresses became light brown with a red tone. A boiling water treatment was carried out for 120 min. The hair tresses were placed in