Dehydration can cause a range of symptoms from brain fog to kidney stones. It can affect people at any age but can be particularly burdensome to vulnerable older adults.
Studies show a high prevalence of chronic dehydration among older adults, which suggests that age elevates dehydration risks. Different definitions of hydration have yielded different statistics on the prevalence of dehydration in older adults, but the numbers range from around 40% to up to 66%.
These stats highlight the importance of staying hydrated for seniors.
[READ: Warning Signs of Dehydration]
Why Hydration Matters More With Age
Dehydration can make anyone feel tired, cranky or dizzy, but in older adults, it’s been associated with worse negative health outcomes. Research has shown dehydration to adversely impact cognitive performance, metabolic and renal disease, length of hospital stay, likelihood of hospital readmission, poor prognosis and mortality risk.
Dehydration may even accelerate aging. A 2023 study by researchers at the National Heart, Blood and Lung Institute found that people who displayed markers for dehydration were more likely to have a higher biological age than their chronological age. If that’s not reason enough to stay hydrated, the research also indicates that maintaining optimal hydration may help slow biological aging, producing major health benefits.
[READ: How Much Water Should You Drink a Day? ]
The Risks of Dehydration in Older Adults
Certain age-related changes can contribute to dehydration, making it more of a problem for older adults than the rest of the population. These include physical changes to the way the body retains water and cognitive changes governing how the body senses dehydration.
“As people get older, all of their sensations tend to diminish,” says Dr. David Cutler, a board-certified family medicine physician at Providence Saint John’s Health Center in Santa Monica, California. That can make them less sensitive to signals that it’s time to replenish fluids.
[Read: How to Prevent Kidney Stones and Improve Kidney Health: Foods to Eat and Avoid]
8 Age-Based Changes That May Increase Risk of Dehydration
Decreased thirst sensation
Aging can diminish your sensation of thirst, leading to reduced fluid intake.
Dr. Brian Lee, the medical director of the Emergency Care Center at Providence St. Joseph Hospital in Orange, California, explains that these changes are natural and related to the brain. “The sensation of thirst is controlled by the hypothalamus in the brain,” he says. “As a part of the normal aging process, the hypothalamus as well as all areas of the brain undergo progressive deterioration of function.
Trouble swallowing
Dysphagia, a condition that impairs your ability to swallow foods and liquids, can be common among older adults in nursing home settings. People with dysphagia may have a decreased ability — or desire — to drink water, and studies have found that dysphagia can be a major risk factor for low-fluid intake.
Reduced kidney function
Aging kidneys naturally lose some of their ability to conserve water and concentrate urine, leading to greater fluid losses through urination.
Changes in body composition
A decline in muscle mass, referred to as sarcopenia, can also reduce how much water the body can store at any given time, as muscle functions as a significant holding area for water molecules.
Some 10% to 20% of older adults have severe muscle loss, according to the Office on Women’s Health in the U.S. Department of Health and Human Services.
Medication side effects
Certain medications — including those commonly prescribed to older adults — can have diuretic effects. Additionally, many older adults use diuretics and laxatives, which increase their risks for dehydration.
“Blood pressure medications such as diuretics are commonly associated with dehydration in the elderly,” says Dr. Sanjay Kurani, medical director of inpatient medicine at Santa Clara Valley Medical Center in San Jose, California. “Antihistamines and laxatives are also medications that can result in dehydration.”
Chronic health conditions
Conditions like diabetes and kidney disease can affect the body’s fluid balance, necessitating careful hydration management.
Cognitive impairments
Memory issues, including those associated with dementia, may cause you to forget to drink water — or impact your ability to recognize and respond to thirst.
Social insecurities and mobility restrictions
Some older adults may voluntarily withhold their fluid intakes due to worries about incontinence or dysphagia. They may also refrain from drinking water if they are socially isolated or unable to safely or easily fetch themselves a beverage.
[READ: What Is IV Therapy? Uses, Benefits and Risks]
Recognizing and Responding to Dehydration
Dehydration occurs when your body does not have enough fluids to meet its needs. This puts your body in a vulnerable state, and can lead to uncomfortable and even dangerous symptoms.
Some early signs of dehydration include:
— Fatigue
— Thirst
If these early signs of dehydration are ignored, they can escalate to these more severe symptoms:
— Dizziness
— Confusion
— Weakness
— Reduced coordination
— Decreased cognitive function
Dr. Audrey Chun, the vice chair of geriatric and palliative medicine outpatient services in the Mount Sinai Health System, says that severe symptoms of dehydration can be “exacerbated in older adults because they are more likely to have underlying chronic conditions and a blunted response to adapt to the physiological stressors that occur with dehydration.”
If you are experiencing early signs or severe symptoms of dehydration, start hydrating yourself immediately by drinking water or other hydrating fluids. If you are experiencing severe symptoms of dehydration that do not abate after drinking water, it is important to seek medical attention.
Medical interventions for severe dehydration may include receiving IV hydration or electrolytes, and may at times require hospitalization.
Preventing Dehydration
Fighting dehydration shouldn’t start with damage control. By familiarizing yourself with your body’s hydration needs and taking preventative measures to increase your water intake, you can reduce the likelihood that you’ll become dehydrated in the first place.
How much water do older adults need?
Daily water recommendations can be incredibly individualized.
One way to prevent dehydration is to calculate how much water your body needs each day, and drink that amount. Start by calculating your body weight in kilograms, and aim to consume that amount per day, Cutler says. Because total hydration includes foods and beverages, you would need to get only about 80% of the number from fluids.
There are also some age-based recommendations, but Cutler says they’re not always helpful, as older adults can be of all different health statuses. Some 70-year-olds may look and act 50 and others may look and act more like 80.
While the Centers for Disease Control and Prevention does not offer a specific water-intake recommendation for older adults (saying instead that it varies by age, sex, pregnancy status, activity level and breastfeeding status), other health agencies offer ballpark hydration goals.
In its 2019 practical guidelines, the European Society for Clinical Nutrition and Metabolism recommends that older women drink at least 1.6 liters of fluids per day and that older men drink at least 2 liters of fluids per day. That translates to a minimum of about 6 to 7 cups of fluid a day for women, and about 8 to 9 cups of fluid a day for men.
Whatever number you shoot for, be mindful of how your body responds to the amount. If you are noticing symptoms of dehydration, for instance, increase your water intake. To get specific medical advice, talk to your doctor.
Practical Tips to Stay Hydrated
Some preventative measures you can take to decrease your dehydration risks include:
— Establishing a hydration routine, which may look like setting an alarm to remind you to drink fluids, or starting a habit of carrying a water bottle with you throughout the day. You can also try habit stacking, the practice of tacking a new habit onto an existing one. So if you tend to watch TV for half an hour each evening, grab a hydrating beverage before you sit down and sip while you watch.
— Choosing hydrating beverages, which can include drinks like water, milk, herbal teas, juices and electrolyte powders. If you find water boring, try adding fresh lemon slices, sprigs of mint or other flavorful fruits.
— Practicing mindful caffeine consumption. Drinking caffeinated beverages is OK in moderation, but don’t let them be your sole source of hydration. Also keep in mind that caffeine can act as a diuretic, increasing dehydration risks.
— Limiting or cutting out alcohol. Cutler discourages drinking alcoholic beverages, as alcohol can be very dehydrating.
— Eating hydrating foods, such as watermelon or other juicy fruits, soups or stews. The body uses food as well as beverages to stay hydrated.
Assessing and Adjusting Your Hydration
To see whether your hydration habits are working, track your beverages along with the color of your urine when you go to the bathroom. Pale yellow urine typically indicates adequate hydration, while darker urine suggests that you are not adequately hydrated and may need to drink more. You may also need to make adjustments for other reasons, such as to accommodate changes in your health status or in response to changes in your environment.
You may want to adjust your hydration plan in light of:
— Mobility and accessibility challenges, to ensure that you can access food and beverages despite physical limitations. Depending on your unique challenges, this could involve having a nurse or a loved one who can fetch things for you, a walker to use while making your way to the kitchen or storing beverages in an easy-to-reach area of your home.
— Hot weather or increased physical activity, to ensure you are drinking more water to cool your body down and compensate for fluid loss through sweat.
— Illnesses, to re-hydrate yourself with water and electrolyte mixes in response to dehydration caused by fever, diarrhea, nausea or vomiting.
Consider speaking with your health care provider about how to individualize your hydration plan to feel more confident that the habits you are setting support your body and goals.
Hydration Precautions
When it comes to drinking water, more isn’t always better. Overhydration is typically less of a health concern in older adults it does pose risks. To avoid overhydration, Cutler recommends that older adults pair water with minerals — such as homemade oral rehydration solutions containing sugar and salt, or store-bought electrolyte solutions — particularly if they are drinking more than a quart of water at a time.
Overall, balance is key.
Older adults “have to be a little bit more careful in keeping their fluid status in a tighter range so they don’t get too much fluids, they don’t get too little fluid,” Cutler says. “It’s very unlikely that a person will either become overhydrated or under-hydrated when they’re a younger adult, whereas it’s more common as an older adult.”
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What Older Adults Need to Know About Hydration originally appeared on usnews.com
Update 06/09/25: This story was published at an earlier date and has been updated with new information.
