Why Hydration Matters More When You’re Taking A GLP-1

Taking a GLP-1 medication can require many lifestyle adjustments, like adapting to a reduced appetite and hitting the gym more often to preserve muscle. One habit shift that’s easily overlooked? The need for increased hydration. 

GLP-1 meds can increase your susceptibility to dehydration—to a potentially dangerous degree—for a few different reasons. Here, dietitians who specialize in treating patients on GLP-1s explain why these medications can leave you low on fluids, and how to stay hydrated and healthy throughout your journey with them.

• ABOUT OUR EXPERTS: Jamie Mills, R.D.N., C.D.N., is a registered dietitian and creator of The Sleeved Dietitian. Bonnie Newlin, M.P.A., M.S., R.D., C.D.N., C.L.T., is a registered dietitian and creator of Crave Nourishment.

Why a GLP-1 May Increase Your Fluid Needs

If you’ve done your homework on GLP-1 drugs, you probably know these meds supply a synthetic form of a particular hormone to mimic the body’s natural fullness cues. But quieting your hunger signals isn’t all they do. “GLP-1 medications work by targeting areas of the brain that regulate both appetite and satiety,” says registered dietitian Jamie Mills, R.D.N., C.D.N., creator of The Sleeved Dietitian. “In doing so, they can also unintentionally mute thirst signals.”

This stunting of your thirst sensitivity can make you forget to drink. “I hear it all the time, my clients will tell me, ‘I had two bites of food all day and realized I hadn’t had any water,’” Mills says. In fact, a 2020 study found that people on GLP-1 drugs had significantly reduced water intake—so much so that researchers speculated the drugs could be used to treat people with excessive thirst.

Meanwhile, some of GLP-1’s common side effects can deplete your fluid reserves. Gastrointestinal issues like nausea, diarrhea, and vomiting are by far the most common side effects associated with these drugs—and they certainly don’t help in the hydration department.

Cutting back on carbs—as many people do when pursuing weight loss—could further exacerbate the issue. “If someone reduces carbs, they naturally lose more water and sodium, which adds to the dehydration risk,” says Mills. (The body responds to an absence of carbs by pulling fluid stores out of the liver and skeletal muscles.)

Finally, if exercise is a part of your weight-loss journey, you might lose extra fluids through sweat—especially if you work out in warm weather, she adds.

Signs of Dehydration to Watch for

Spotting GLP-1-related dehydration may be harder than you expect. “GLP-1 medications can blunt your thirst cues, so you might not realize you’re becoming dehydrated until symptoms start to build,” says registered dietitian Bonnie Newlin, M.P.A., M.S., R.D., C.D.N., C.L.T., creator of Crave Nourishment. In other words, simply waiting for feelings of thirst might not be enough. “Signs of dehydration can show up as dry mouth, fatigue, dizziness, lightheadedness, headaches, dark yellow urine, constipation, and muscle cramps, particularly in the legs,” she says. Experiencing these alone or in combination likely means it’s time to grab your water bottle.

Read More: Signs Your Electrolytes Are Off-Kilter—And What to Do About It

Increasing dehydration can also upset the natural order of your electrolytes. “Electrolyte imbalance leads to symptoms like muscle weakness, heart palpitations, numbness or tingling in the hands or feet, brain fog, confusion, irritability, nausea, low appetite, or cramping that isn’t tied to physical activity,” Newlin says. These more serious symptoms warrant a consultation with your healthcare provider.

How To Get Your Fluid Fix While on GLP-1s

If you’re taking a GLP-1, extra vigilance around hydration may be necessary. “These medications help you not think about food (and inherently reduce your thirst signals), so you’ve got to outsmart that,” Mills says. She and Newlin agree that at least eight cups of fluids per day is a good target—though you’ll need more if you’re physically active or experiencing side effects. 

Thankfully, plain old water isn’t the only way to up your fluid intake! Herbal teas, bone broth, electrolyte drinks, and water-rich foods like cucumber, zucchini, and berries can all help increase hydration.

To reach your daily goal, try these strategies:

• Keep a large water bottle within reach throughout the day. If water is out of sight, it’ll be out of mind. Having a bottle close at hand is a good visual reminder.
• Invest in a bottle that suits your personal style. When you like the look and feel of your water container, you may be more likely to tote it around with you.
• Try room-temperature liquids. According to Mills, cold water can trigger nausea for some people taking GLP-1s, while room-temperature fluids may go down more easily.
• Set hourly hydration reminders on your phone or other device. Since you may not be able to count on thirst cues, use technology to hold yourself accountable.

When To Consider a Hydration Supplement

In the case of GLP-1s, even the best of hydration intentions may not be enough to keep you properly stocked on fluids. That’s where an electrolyte supplement comes in. Though you might associate electrolyte replacements with intense exercise, Mills says they’re a handy fix for all kinds of fluid deficits. “Electrolyte support isn’t just for marathon runners; it’s for anyone whose intake is lower than usual, which happens a lot on GLP-1s,” she shares.

Read More: Are You Making These Common Hydration Mistakes?

If you know you’re not meeting your fluid goals or are experiencing symptoms like fatigue, dizziness, or muscle cramps, a hydration supplement is probably in order, suggests Newlin. “Look for options that contain sodium, potassium, and magnesium, especially when in an active weight-loss phase or experiencing side effects,” she recommends.

Which of the plethora of hydration supplements out there is right for you? The one you’ll use—and enjoy! Mills advises considering factors like sweetness, flavor, and gentleness on your stomach. “You don’t need to overdo it, but having an electrolyte supplement on hand a few times a week can make a huge difference in how your body feels and functions.” If you need a little help selecting the ideal hydration support for your needs, check in with the healthcare provider managing your prescription or a dietitian well-versed in GLP-1s.

Other Supplements to Consider When Taking a GLP-1

Alongside your hydration supplement, it’s wise to consider taking a daily multi like Whole Health Rx GLP-1 Support Multivitamins. With any caloric deficit, there’s a chance you’ll create a nutrient deficit. These multis, as well as the GLP-1 Support Nutrient Powder, can help fill the gaps in your diet. Meanwhile, the GLP-1 Support Synbiotic promotes healthy digestion and GLP-1 Support Fiber encourages bowel regularity and stimulates the body’s natural GLP-1 levels with clinically studied patented ingredients like Fibersol^®-2, inavea™, and NatureKnit™.