"feel thirsty" is correct and usable in written English.
You could use it to describe how someone feels after a long day in the sun, for example: "I feel thirsty after spending the afternoon at the beach."
Once you feel thirsty, you are already low on fluids.
Then continue to drink as you feel thirsty.
"Sure, sometimes I would feel thirsty, but ultimately my faith was my motivation.
By the time you feel thirsty, your body is likely to be pretty dried out.
In fact, if you feel thirsty, your body may be on its way to being dehydrated already.
Officials are issuing standard warnings about how to stay healthy: Drink plenty of water, and do it regularly; don't wait until you feel thirsty.
I once wrote a book that meant I had to come to Qom a lot, and it always made me feel thirsty.
Our current thinking is that you should drink only when you feel thirsty, and not force yourself to take in more fluid than your body needs.
If you don't get enough, your body will hold on to what it has, you'll feel thirsty and you'll urinate less.
Once you feel thirsty, the body is already behind on getting hydrated.
● After eating, your increased blood sugar usually makes you feel thirsty and you need visit the toilet more often than usual.
