Hydration: What to Know for Hot Weather

Tufts University

This article originally appeared in the Tufts Health & Nutrition Letter, published each month by the Friedman School of Nutrition Science and Policy. Find out how to get expert guidance on healthy cooking, eating, and living.

It’s hot out! High temperatures increase the risk of dehydration. Fluids are critical to optimal body function. They help regulate body temperature, control blood pressure, deliver nutrients and oxygen to cells, and aid proper functioning of the gastrointestinal system. When fluid levels drop, a wide variety of systems in the body are affected. Knowing the signs and symptoms of dehydration-and how to avoid them-can get us safely through the heat of summer.

Dehydration Defined

Dehydration occurs when you lose more fluid than you take in. It can lead to everything from minor cramps and heat exhaustion to seizures and potentially life-threatening heatstroke or shock.

Thirst is one way the body alerts us of low fluid levels. “Drink to satisfy your thirst,” says Klemens Meyer, MD, a nephrologist and director of Dialysis Services at Tufts Medical Center. Other symptoms are fairly general and include dry lips, mouth, or tongue; headache, dizziness, or lightheadedness; fatigue or lethargy; lack of focus; muscle weakness or muscle cramps; and rapid breathing. Urine color is a possible indicator of hydration in children and young adults, but not necessarily in older adults. When hydrated, urine is light and straw-like in color. Very dark colored urine is a sign of dehydration. “If your urine is dark, drink water to make it lighter, but not so much that it looks like water,” says Meyer.

/Courtesy of Tufts University. This material from the originating organization/author(s) may be of a point-in-time nature, edited for clarity, style and length. The views and opinions expressed are those of the author(s).