Do you drink coffee in the summer? Some feel it is too hot to do so. While it is important to keep hydrated with actual water in hot weather, I find a good cup of coffee can actually cool me down in the heat.
Granted, I will find any excuse to justify my coffee habit, but there is science to back this one up. It depends on the circumstances, but a nice hot cup of coffee (or any hot beverage) will indeed cool you down. It has to do with the temperature of your body on the inside.
If the increased inner temperature causes you to sweat, and the sweat then evaporates, this will indeed cool you off. If it is too humid for the sweat to evaporate; however, this will not help. Sadly, I live in a rather humid climate. Still, there are many days that I have found it helps. Having a fan in a window directly in front of work area probably helps as well, for it lets the sweat evaporate even on more humid days.
Humidity aside, I am a coffee nut! Though family members constantly berate me for its potential affect on my health, the above information does bear out at least one positive factor in my favor. In winter, of course, my excuse is that it keeps me warm, and it does indeed do just that. Even holding a cup of hot coffee can warm cold hands in winter.
Personally, I think it also helps that I drink it black. Sugar, cream, and other sweeteners and flavorings can cause other health concerns. I wonder if such sweeteners make a difference with regard to the heat. I think they may, but have not yet found any supporting evidence for this. I feel experiments regarding heat and blood sugar levels may be in order here.
Depending on the humidity in your area, a hot cup of coffee may be the answer to cooling off. It never hurts to try, and you can always alternate with fresh cool water as I do. These are pretty much the only two things I drink in summer, so perhaps I am keeping things in balance at least.
Additional source : Personal commentary and experience with regard to the articles linked above.