1 doctor weighed in:

What causes decreased thirst/fluid intake?

1 doctor weighed in
Dr. John Garner
Internal Medicine - Cardiology

In brief: A Couple of Things

Thirst is controlled by a center in the brainstem. That center is sensitive (exquisitely so) to the concentration of sodium in the blood.
So, from that, you can gather the two simple answers. If the sodium level is too low for any reason, it would require more than usual dehydration to raise it to the level triggering thirst. If the center is less responsive (old age) the thirst signal is weaker.

In brief: A Couple of Things

Thirst is controlled by a center in the brainstem. That center is sensitive (exquisitely so) to the concentration of sodium in the blood.
So, from that, you can gather the two simple answers. If the sodium level is too low for any reason, it would require more than usual dehydration to raise it to the level triggering thirst. If the center is less responsive (old age) the thirst signal is weaker.
Dr. John Garner
Dr. John Garner
Thank
Read more answers from doctors