Why do some people go red when they are hot?

When people get hot, their body temperature rises, leading to the dilation of blood vessels near the skin's surface to help cool down. This increased blood flow can cause the skin to appear red or flushed. Factors such as physical exertion, emotional responses, or environmental heat can trigger this reaction. Additionally, individuals with lighter skin tones may show this redness more prominently due to lower melanin levels.