Cranky? Thirsty? Slurp some lettuce or melon

When the mercury hits 90 and above, tempers can get pretty fired up, too. But another glass of water or a slice of watermelon might help, because irritability is a classic side effect of dehydration.

The first physical sign is thirst, of course. But other symptoms are more subtle. You might get a headache. You can become cranky, forgetful, tired, and dizzy, and your skin appears dry and wrinkly.

Remember the old admonition to drink eight glasses of water a day? Well, in 2004, the Institute of Medicine issued new general fluid recommendations indicating women should drink 11 cups per day and men 15 cups.

These amounts include the water in all food and beverages we consume. Iced tea, fruit juice, and even hot coffee and soups all count as hydrators. It turns out that 80 percent of our water intake is from drinking water and other beverages, and the other 20 percent is from food.

Watermelon, a summertime favorite, is more than 90 percent water. Other foods with high water content include lettuce, peaches, broccoli, and citrus fruit. The Georgia Peach Council handed out more than 10,000 fresh peaches during the AJC Peachtree Road Race on July 4.

It's worth noting that iceberg lettuce, often dismissed as having little nutritional value as compared with its dark green leafy cousins, is a better source of water. Just go easy on the blue cheese dressing.

Sports fitness experts say it's best to drink small amounts at a time throughout the day, because the body is better able to absorb the fluids.

Avoid sugar-sweetened beverages such as soft drinks and sweetened ice tea, because they come with a hefty calorie count - 150 calories for a 12-ounce soft drink. Studies show that Americans are consuming 220 more calories a day from sugar-sweetened beverages than they did in the 1960s.

If you want the bubbles, choose zero-calorie flavored sparkling waters or good old club soda.

Fruit juices provide nutritional benefits, including antioxidants and vitamins needed to help keep summer bodies at their best.

"Drinking water - either sparkling or flat and perhaps with a twist of citrus - is a great, noncaloric way to satisfy your thirst. But if you prefer 100 percent fruit juice, low-fat milk, coffee, or other flavored beverages, they too can keep you well-hydrated," said Kathleen Zelman, Atlanta dietitian and nutrition director for WebMD.

"Bottom line, make your beverage choices work to satisfy your nutritional needs, fluid preferences, and hydration needs."

Fruits and vegetables are foods with especially high water content. So, when you choose gazpacho or a peach cobbler, you're helping to hydrate your body.

Here's how the percentage of water plays out:

Iceberg lettuce, cucumbers - 96 percent

Cabbage, celery - 95 percent

Tomatoes - 94 percent

Watermelon, strawberries, spinach, eggplant - 92 percent

Broccoli, citrus - 91 percent

Carrots, pineapple, peaches, raspberries - 87 percent

Yogurt, blueberries, plums - 85 percent

Apples - 84 percent

Bananas - 74 percent