1. What is skin sebum?
Sebum plays a key role to lubricate, coat and protect your skin. It is an oily, waxy substance secreted by sebaceous glands that are often grouped around pores. 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 skin. On the other hand, hormone changes, for example increase of sex hormone, and some hormonal medications can lead to increased sebum production. Acnes develop when excessive amount of sebum and dead skin cells plug pores.
To assist diagnosis of skin sebum, we provide absorbent sebum strips to tag your skin. Press the sebum strip moderately onto skin for 10 seconds, remove sebum strip and take an image with the PPL light mode of our Chowis Mobile Analyzer for Skin. Repeat the process for both T-zone and U-zone. Our algorithm then evaluates the sebum spots in the images and provides the grading.
Figure 1. Skin sebum strips
2. Chowis skin sebum grade
The following Chowis skin 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 skin sebum into very dry, dry, normal, oily and very oily.
| Grade | Scale | Description |
|---|---|---|
| Very dry | 0 ~ 5 | Dry skin with really low sebum secretion |
| Dry | 6 ~ 15 | Scalp with mildly low sebum production |
| Normal | 16 ~ 48 | Normal skin with balanced sebum secretion |
| Oily | 49 ~ 80 | Skin with mildly increased sebum production |
| Very oily | 81 ~ 99 | Oily skin with highly excessive sebum secretion |
| Very dry |  |  |
| Dry |  |  |
| Normal |  |  |
| Oily |  |  |
| Very oily |  |  |