Will my feet be cold in such thin socks?

Surprisingly, thin cross-country socks often keep feet warmer than thick ones during active Nordic skiing. The reason is moisture management: thick socks trap sweat, and wet skin gets cold quickly, especially during rest stops. Thin merino socks wick moisture away from the skin, keeping feet dry and maintaining warmth. If your feet are cold in thin socks while actively skiing, the issue is more likely boot fit, circulation restriction, or insufficient overall insulation elsewhere — not the sock thickness.