Do pores really shrink and expand based on temperature?
Many people have heard the saying, "hot water expands pores, cold water shrinks them." Especially when it comes to skincare, many people want to use this principle to choose products or perform treatments.
What causes pores to shrink or expand?

Actually, there's a muscle under the skin called the Arrector Pili Muscle, which relaxes when hot and contracts when cold, similar to goosebumps in winter.
However, pores themselves are small holes in the skin, and muscles cannot truly contract or expand them. Therefore, neither hot nor cold water will actually change pore size.
Gentle hot water or steam can help release oil, and cold water can soothe the skin, but water that is too hot or too cold can irritate the skin and cause sensitivity.
Recommended Moisturizing Products for Healthy Pores
While temperature won't directly change pore size, keeping skin well-hydrated and maintaining an oil-water balance can make pores appear smaller and smoother.
For daily care, consider the following moisturizing and repairing products:
SOS Booster Deep Hydrating Serum
- Provides instant hydration to the skin
- Helps calm skin and maintain a healthy pore environment
All-Round Antioxidant Repair Mask
- Deeply nourishes skin through overnight repair
- Long-term use can improve skin dryness and fine lines, making pores smoother
- Locks in skin moisture and prevents moisture loss
- Better results when used with serum or mask
Frequently Asked Questions (FAQ)
Q1: Do pores shrink or expand with temperature? ▸
Q2: Why is it often said that "hot water expands pores, and cold water shrinks them"? ▸
Q3: What are the skincare benefits of using hot or cold water? ▸
Cold water: Can soothe the skin and relieve irritation.
⚠️ Note: Water that is too hot or too cold may irritate the skin and cause sensitivity. Pair with All-Round Antioxidant Repair Mask or SOS Booster Locking Cream for better results.
Q4: How can I make my pores appear smaller and smoother? ▸
- SOS Booster Deep Hydrating Serum — Instant hydration, strengthens skin barrier
- All-Round Antioxidant Repair Mask — Deep repair and nourishment, improves dryness and fine lines
- SOS Booster Locking Cream — Locks in moisture, prevents loss, works even better with serum or mask