Dehydration in older adults is more common than in younger individuals due to several factors that naturally come with aging, such as new health conditions. If left untreated, dehydration could have many negative effects, including an increased risk for falls and cognitive decline. It’s crucial to keep an eye out for dehydration symptoms in elderly adults and help seniors in your life stay hydrated. It’s especially pertinent in the summer due to the increase in heat and humidity.
What Is Dehydration?
Dehydration is a condition that occurs when the body loses more fluids than it takes in, which causes water and electrolytes to deplete. This can be dangerous because water and electrolytes help the following crucial bodily functions, according to research on the importance of hydration at Harvard:
- Body temperature regulation
- Delivery of essential nutrients and oxygen to cells
- Digestion
- Joint lubrication
- Organ protection
- Waste removal
Dehydration in the elderly can have many negative effects including the following, according to research on the effects of dehydration in older people:
- Constipation
- Increased risk of falls
- Increased risk of metabolic and kidney diseases
- Infections
- Mobility issues
- Poor cognitive performance
Types of Dehydration
It’s important to note that there are different types of dehydration with various effects, according to adult dehydration research:
- Isotonic dehydration is when the body loses both water and sodium equally, which often occurs with vomiting, diarrhea, and hemorrhage. This may cause tachycardia (an increased heart rate), low blood pressure, and reduced blood flow to organs.
- Hypertonic dehydration is when the body loses more water than sodium, which results in hypernatremia—too much sodium in the blood. This can lead to confusion, seizures, and coma.
- Hypotonic dehydration is when the body loses more sodium than water, which causes hyponatremia—not enough sodium in the blood. This is common in individuals taking diuretics or those with chronic kidney disease, and can cause muscle weakness, lethargy, and swelling in the brain due to excessive fluid.
What Causes Dehydration in Seniors?
Older adults are at increased risk of dehydration because they often face a reduced thirst sensation and have comorbid conditions.
Causes of dehydration in elderly adults may including the following, according to current knowledge on hydration in older adults:
- Decreased sense of thirst. Older adults sometimes don’t feel as thirsty as younger individuals, which leads to less water intake.
- Decline in cognitive function. Older adults may forget to drink sufficient water due to memory loss that comes with normal aging or dementia.
- Limited mobility. For some seniors, it may be harder to get around, which could make it harder to get up for water as often.
- Medication side effects. Some medications, especially diuretics and some blood pressure medications, increase urination and fluid loss.
- Urinary incontinence. Seniors who no longer have control of their bladder may restrict their own water intake to prevent accidents.
- Dysphagia (or difficulty swallowing). Some conditions may make it harder for a senior to swallow, which can lead to less water intake.
What Are the Symptoms of Dehydration in the Elderly?
Dehydration signs may vary depending on the senior. To help you catch it early, take a look at this extensive list of common signs of dehydration in the elderly, according to dehydration symptoms published by the National Library of Medicine:
- Decreased urination or dark urine
- Decreased sweat
- Dry mouth or excessive thirst
- Dry skin
- Fatigue or lethargy
- Lightheadedness or dizziness
- Weak muscles
Some dehydration symptoms in seniors may be more severe. If any of the dehydration signs listed below are present in a senior, the National Library of Medicine suggests seeking medical help immediately:
- Confusion
- Fainting
- Lack of urination
- Rapid heartbeat or breathing
- Shock
How Can You Prevent Dehydration?
There are many options to prevent dehydration in yourself or a senior loved one. Here are some hydration tips to help seniors stay replenished, especially in the hotter months:
- Keep water accessible. Keep a water bottle within reach to continually drink water throughout the day without having to get up every time.
- Drink water throughout the day. If a senior wakes up or takes medication at the same time every day, try to get them to drink a full glass of water rather than just a sip. Also try taking a water bottle when leaving the house or adding water reminders to their phone.
- Make water more appealing. If water isn’t enough on its own, add in citrus fruits, cucumber, berries, mint, or ginger. Infused water can help seniors drink more water and provide some essential nutrients.
- Drink other hydrating beverages. Although water is the best option, seniors can still get some hydration from other drinks like milk, flavored sparkling water, and low-sugar fruit juices. Electrolyte drinks may also be a good option on some days where you need some extra help but be sure to talk to your doctor before drinking one.
- Minimize dehydrating beverages. It’s best to limit drinks that are high in sugar, caffeine, or alcohol. Excessive amounts may lead to dehydration, especially alcoholic beverages because alcohol is a diuretic.
- Eat hydrating foods. Incorporate hydrating foods like watermelon, strawberries, cucumber, celery, and low-sodium broths or soups.
How Much Water Should Seniors Drink?
The amount of water a senior should drink is about 11.5 cups per day for women and 15.5 cups for men, according to the Academy of Nutrition and Dietetics recommendations on water intake. This is based on 8-ounce cups; therefore, women should drink 2.7 liters (or 91 ounces) of water per day, while men should drink 3.7 liters (or 125 ounces).
It’s very important to note that water intake needs may vary among seniors due to their health conditions and activity level. For instance, seniors taking diuretics may need to drink more water if their doctor says so. It’s highly recommended that you talk to your loved one’s primary care team before making any changes to their water intake.
If you are worried about your senior loved one’s nutrition, ability to stay hydrated—or even manage daily tasks independently—it may be time to consider senior living. Find a Sunrise community near you to learn how our team members can help your loved one lead a longer, healthier, happier lifestyle.
References
[1] Harvard T.H. Chan School of Public Health. (2024, November). The importance of hydration.
[2] Edmonds, C. J., Foglia, E., Booth, P., Fy, C. H. Y., & Gardner, M. (2021, August). Dehydration in older people: A systematic review of the effects of dehydration on health outcomes, healthcare costs and cognitive performance. Archives of Gerontology and Geriatrics.
[3] Taylor, K. & Tripathi, A. K. (2025, March). Adult Dehydration. StatPearls Publishing.[4] Li, S., Xiao, X., & Zhang, X. (2023, June). Hydration status in older adults: Current knowledge and future challenges. Nutrients.[5] MedlinePlus. (2023, December). Dehydration. U.S. National Library of Medicine.
[4] Li, S., Xiao, X., & Zhang, X. (2023, June). Hydration status in older adults: Current knowledge and future challenges.
[5] MedlinePlus. (2023, December). Dehydration. U.S. National Library of Medicine.
[6] Gordon, B. (2022, June). How much water do you need? Academy of Nutrition and Dietetics.