Is there a perfect time to apply your scalp oil?

Our bodies follow a biological rhythm where it performs certain tasks in response to our exposure to light and dark (it is also what regulates our sleep-walk cycles). This is called the circadian rhythm. It was initially believed that there was only one central clock for our body in our brains, but further research has proven that there are clocks everywhere in the body. 

So, let’s talk about the hair clock, or rather, the scalp clock. The circadian rhythm of our scalp has our hair growing the fastest during the day, and transitions into cellular repair mode in the evening into the night.

There was an incredible study by researchers from Salk Institute for Biological Studies, the University of Southern California (USC) and the University of California, Irvine (UCI) which found that mice lost 85% of their hair if they received radiation therapy in the morning, compared to a 17% loss when the treatment occurred in the evening. Why? Remember, our scalp goes into repairs at night so if you apply radiation treatment in the morning, it’s many hours until your scalp is going into repair mode. But if you apply radiation therapy later in the evening, your body is naturally going into the cellular repair phase soon, so the chances of hair loss are significantly less.  

Pause and read that last paragraph again. The hair loss was reduced by 68%, that is how hard our cellular repair process works.

So, in theory, the ideal time to apply a scalp oil is the night before you wash your hair. This way, the oils have time to penetrate the scalp and aid in cellular repair process while you are sleeping and help boost your hair growth in the morning. It’s also why there are nighttime creams specifically tailored for nighttime use, for example.

With all that said, when it comes to scalp care, we need to do what fits best with our schedules and preferences. You may not like sleeping with oil on your scalp in which case applying your scalp oil one hour before a hair wash is still better than not applying it at all. The key to scalp care for healthy hair is always going to be consistency. Create a routine that you know you can stick to.

References

Lin, K. K., Kumar, V., Geyfman, M., Chudova, D., Ihler, A. T., Smyth, P., Paus, R., Takahashi, J. S., & Andersen, B. (2009). Circadian clock genes contribute to the regulation of hair follicle cycling. PLoS genetics, 5(7), e1000573.

Lyons, A. B., Moy, L., Moy, R., & Tung, R. (2019). Circadian Rhythm and the Skin: A Review of the Literature. The Journal of clinical and aesthetic dermatology, 12(9), 42–45.

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A Circadian Clock in HaCaT Keratinocytes,

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