boost your healthspan with food and nutrition

Hydration smarts for older adults

Hydration smarts for older adults

A few weeks ago I listened to a webinar that presented some rather alarming information about hydration in older adults. Food intake surveys show that for age 70+, 80% of women and almost all men fail to meet even the minimum fluid intake recommendations. The average deficit came out to 2.5 cups fluid/day for women and more than 5 cups for men.

Why is this alarming? Poor hydration status has a serious detrimental impact on older people’s health. Worse, the adverse effects can happen quickly, before your thirst signals kick in. There is a signicant lag time between when your brain and kidneys first sense dehydration and when you get thirsty.

During that lag time, things can go haywire. As you become more dehydrated, you might feel ‘off’ — lightheaded, faint, weak. This can be especially acute in hot weather. Mood, cognitive performance, exercise performance and energy can all be impacted. Chronic dehydration aggravates heart disease, kidney disease, diabetes and blood pressure. Hydration status is linked to higher risk for kidney stones.

How much water?

Here are the U.S. recommended fluid intake for older adults:

  • males: 3.7 liters
  • females: 2.7 liters

These values are higher than the “8 glasses a day” rule of thumb. The difference can be made up by the water content of foods and other beverages you consume. Coffee, tea, milk, juices and soft drinks count as fluid sources. High water content foods like lettuce, watermelon, cucumbers, berries, melons, citrus fruits, papaya, pears and tomatoes can contribute significant fluid if you consume lots of fruit and vegetables. Which you should do on a plant-based diet. Most fruits and vegetables have high water content. Of course, if you’re concerned about calories, and getting enough other nutrients like protein, it’s best to get most of your fluid from plain water. Eight glasses a day isn’t a bad starting point.

Am I getting enough?

How do you know if you’re consuming enough fluid from whatever source? This is the tricky part. Dehydration can be identified with lab tests, but that’s not realistic for daily life. You may have seen a recommendation to judge from the color of your urine. But no one explains how you do that. Do you pee into a cup all day? That seems extreme. One of the webinar speakers suggested that you should pee 5 times a day, not counting first thing in the morning (which makes 6). If you have bladder problems, this might not be a great indicator.

Some situations increase fluid needs. When they overlap, pay attention. Older people are more susceptible to ill effects from very hot weather. Add low humidity or exercise and your fluid needs increase. Acute problems like vomiting or diarrhea, can easily lead to dehydration. Certain food bourne pathogens can cause those problems, and older people can have more severe symptoms from these infections.

Then there are the dehydration aggravators: heavy sweating, alcoholic beverages, certain medications. If you have existing medical conditions, your physician should tell you about any potential hydration issues. Likewise for medications. Certainly if you have heart or kidney disease that may impact your fluid balance, you need to adhere to any fluid restrictions from your medical provider.

Don’t sweat it!

Adequate hydration doesn’t have to be complicated. Follow a few common sense guidelines.

  • Drink plain water during the day. Create a reminder for yourself: fill a pitcher or large water bottle in the morning and drink from it throughout the day.
  • Don’t let thirst be your guide, especially in hot, dry weather.
  • Include plenty of high-water content fruits and vegetables in your daily diet.
  • In very hot/dry weather, monitor yourself for unusual fatigue or dizziness, and increase fluid intake, especially if you’re exercising outdoors.

Bored with plain water?  Make infused water by adding cut up fruit or fresh herbs to a pitcher of water.  Cucumbers, melon, strawberries, peaches, pineapple, mint and basil all work well.  This aqua fresca recipe makes hydration both tasty and nutritious.

Watermelon Strawberry Aqua Fresca

June 13, 2023
: 1-2
: 15 min
: 15 min
: easy

You can use a regular blender or an immersioin blender for this fruity drink, if your blender came with a special blending container. I use watermelon and strawberries, but you can just use watermelon, increase to 1-1-2 cups cubes. Mint leaves are optional.


  • 1 cup seeded watermelon cubes
  • 2-3 strawberries, sliced
  • 2-3 tsp sugar, or to taste
  • 1 cup ice cubes
  • juice from 1/2 small lime
  • 2-3 fresh mint leaves (optional)
  • Step 1 But everything but the mint leaves in a blender.
  • Step 2 Pulse to crush the ice cubes, and blend until relatively smooth.
  • Step 3 Pour into a glass and garnish with mint leaves.