1. What Is Hair Shine?

Sebum is an oily, waxy substance secreted by sebaceous glands that are often grouped around hair follicles. It plays a key role to lubricate, coat and protect your scalp and hair. When hair is adequately moisturized by sebum, it tends to appear smoother, softer, and shinier. However, many factors can change sebum secretion and both sebum deficiency and increased sebum production can cause concerns. For example, insufficient sebum secretion can result in dry, brittle hair that lacks shine and elasticity. On the other hand, excessive sebum production can lead to oily hair which can appear dull and weighed down. In the absence of other tools (e.g. sebum paper) we analyze hair shininess as an indirect but adequate measure of hair sebum level. To assist diagnosis of hair shine, up to 5 images can be taken under the PPL light using the Chowis Hair Analyzer. Our companion algorithm them evaluates the hair shine for each image and provides the final hair shine level.

2. Chowis Hair Shine Grade

The following CHOWIS hair shine grade has been co-developed by CHOWIS and dermatology experts. For each image, we detect shine to provide a quantified score. Based on the scale shown in Table 1, we grade hair shine into very dry, dry, normal, oily, and very oily.

Table 1. Hair shine grade as indirect measure of hair sebum.

Grade	Scale	Description
Very dry	0~5	Dry scalp with really low sebum secretion.
Dry	6~15	Scalp with mildly low sebum production.
Normal	16~48	Normal scalp with balanced sebum secretion
Oily	49~80	Scalp with mildly increased sebum production.
Very oily	81~99	Oily scalp with highly excessive sebum secretion.