The key to staying hydrated during the hot summer months is drinking plenty of water — but different foods can provide ample hydration, too.

Failing to eat the right foods can cause a water imbalance, particularly in high temperatures, according to registered dietitian and Trimly coach Kim Shapira in Los Angeles.

"Higher temperatures and outdoor activities can lead to water imbalance," she told Fox News Digital. "We lose water through sweat, saliva, urine and feces. The more we sweat, the more water we lose."

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While drinking water is helpful, getting electrolytes and minerals from hydrating foods can help fully restore what is lost through sweat, according to registered dietitian and nutritionist Ilana Muhlstein, who is based in California.

Next time you hit the beach or are preparing for a heat wave, consider reaching for these four hydrating foods.

Watermelon is "nearly universally loved and incredibly hydrating," a doctor said. (iStock)

1. Watermelon

While drinking water is essential, it’s also important to incorporate electrolytes, which are found in watermelon, according to natural health expert Dr. Joseph Mercola, founder of Mercola.com.

Watermelon is "nearly universally loved and incredibly hydrating," said the Florida-based Mercola.

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"I typically eat 3 to 4 pounds a day," he told Fox News Digital. 

"Even though cucumbers have marginally more water content at 96%, watermelon is the winner," he added. "You can eat far more watermelon than cucumbers."

A registered dietitian recommended adding cubed watermelon to cold water. (iStock)

Watermelon is also rich in vitamins A and C, magnesium and lycopene, according to the expert.

"Some studies suggest it may also aid in muscle recovery after exercise," he added.

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Muhlstein also recommended watermelon, mentioning that the fruit contains about 92% water and is rich in electrolytes and potassium — which help replenish the body’s hydration levels.

"You can add cubes to your cold water bottle," she suggested. "It makes such a refreshing drink that’s sure to help cool you down."

In addition to its hydrating qualities, watermelon is also rich in vitamins A and C, magnesium and lycopene. (iStock)

2. Cucumbers

Cucumbers have the "highest water content of any solid food" at 96%, Mercola noted.

They are also a good source of vitamin K and potassium, he added. 

Cucumbers have the highest water content of any food at 96%. (iStock)

Cucumbers are great for hydration, agreed Muhlstein — as, like watermelon, they’re "mostly water."

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She recommended slicing them into spears and serving them along with hummus, tzatziki or guacamole for an "awesome poolside snack."

3. Carbohydrates

Foods with carbohydrates could help with proper hydration, according to Shapira.

"It helps with dehydration when water is attached to sugar," she told Fox News Digital. 

"It makes it accessible to enter your cells and hydrate you properly."

Pasta or rice can provide 60% to 70% water per half cup, according to a nutritionist. (iStock)

A variety of fruits and vegetables fall into the carbohydrate category, Shapira said, including cucumbers, bell peppers, celery, zucchini, oranges, strawberries and watermelon — which all contain around 85% to 95% water.

Starches like pasta or rice can also provide 60% to 70% water per half cup, the dietitian added.

4. Salad greens

Leafy greens like lettuce, spinach, arugula and kale are all hydration-friendly foods.

These salad greens are "packed with water, fiber, vitamin C and iron," according to Muhlstein.

Greens are packed with water, fiber, vitamin C and iron, a dietitian said. (iStock)

Greens are also essential for energy levels and overall hydration.

"Enjoy meals like BBQ chicken salads, or add them to wraps and smoothies for a hydrating boost," Muhlstein suggested.

Signs of dehydration

Some warning signs of possible dehydration include fatigue, headache, dizziness, dry tongue and, in extreme cases, nausea and vomiting, Shapira said.

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The expert encouraged people to look out for these symptoms during the sweltering summer months.

"It’s a good sign that you need more water, or foods with water in them," she said. 

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When spending two hours or more in high temperatures, Shapira recommended adding electrolytes to water.

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