I have tremendous problems regulating my body temperature. I am either burning up or freezing cold with virtually no middle ground. If I get hot for even a few minutes, my face and my ears will turn bright red and stay that way for literally hours (the same thing also happens when I blush). The most important thing I have learned about myself is that if I am warm, I must be drinking water at all times. If I don’t, I will pay for it in a few hours. I keep a water bottle and a salty snack in my purse and several in my car. Water helps, but water and salt (either from food or a tablet) helps more. If I am forced to spend a long afternoon in the sun, I will often sit in my bed at night and suck on an extra salt tablet and drink several cups of water. This really helps.
The other thing I have noticed is that while being cold is uncomfortable, when I am cold I generally do not feel as light-headed. Because of this, I tend to keep the thermostat in my house set a little cooler than most. This also means that exercise must be done early in the day or late at night, or preferably inside a nice cold air-conditioned building. It also means that if I have to walk outside in the winter, opting for a lighter jacket is the best choice.