Skin color does not affect your heart rate; however, what influences your heart rate is exercise, breathing, medications, illness, having the flu, dehydration, and cardiovascular disease. When you have dehydrated your body temperature changes, and it may also influence your heart rate. Many different influences can impact how many times your heart beats per minute.
Your heart rate has great variability, and it can frequently change throughout the day. Age and gender also influence heart rate; for example, women have faster heart rates because they are smaller. Your maximum heart rate decreases with age; however, skin color is not indicative of a slower or more rapid heart rate.