Measurement Guide

1. What is scalp sebum?

Sebum plays a key role to lubricate, coat and protect your scalp and hair. It is an oily, waxy substance secreted by sebaceous glands that are often grouped around hair follicles. Many factors can change sebum secretion, and both sebum deficiency and increased sebum production can cause concerns. On one hand, sebum secretion decreases as we age. But malnutrition and starvation, and some medications, e.g., birth control pills, can also reduce sebum production. Insufficient sebum can lead to dry and cracked scalp. On the other hand, hormone changes, for example increase of sex hormone, and some hormonal medications can lead to increased sebum production. Inflammations develop when excessive amount of sebum and dead skin cells plug hair follicles.

To assist diagnosis of scalp sebum, we provide absorbent sebum strips to tag your scalp. Press the sebum strip moderately onto scalp in hair parting area for 10 seconds, remove sebum strip and take an image with the PPL light mode of our Chowis Mobile Analyzer for Hair. Our algorithm then evaluates the sebum spots in the image and provides the grading.

Figure 1

Figure 1. Scalp sebum strips

2. Chowis scalp sebum grade

The following Chowis scalp sebum grade has been co-developed by Chowis and dermatology experts. For each image, we detect sebum to provide a quantified score. Based on the scale shown in Table 1, we grade scalp sebum into clear, very clear, mild, moderate and severe.

Table 1. Scalp sebum grade
GradeScaleDescription
Clear0 ~ 9Dry scalp with really low sebum secretion
Almost Clear10 ~ 20Scalp with mildly low sebum production
Mild21 ~ 54Normal scalp with balanced sebum secretion
Moderate55 ~ 85Scalp with mildly increased sebum production
Severe86 ~ 99Oily scalp with highly excessive sebum secretion
Table 2. Representative images of scalp sebum grade
ClearImageImage
Almost ClearImageImage
MildImageImage
ModerateImageImage
SevereImageImage