The simplest, most natural form of disease prevention there is
Did you know that proper hydration is really the cornerstone behind good health—and the backbone of a healthy, balanced diet?
That’s why, every single time I see my patients, I quiz them about what they’ve been eating and drinking. And believe it or not, one of the most common themes that seem to arise is how much water they don’t drink.
But let me be clear: Dehydration is a very real problem… any time of the year. (Yes, even as we welcome a new season of cool weather.)
There are many signs of inadequate water consumption: Dry skin, dry mouth, and dry eyes are the most obvious. But there’s also a whole constellation of problems that you may not associate with poor hydration. Things like weight gain and obesity, depression and anxiety, headaches, poor kidney function, and cognitive decline and brain fog, to name a few. (I could honestly fill an entire newsletter listing the ways your body struggles when it’s deprived of water.)
But the most dangerous part of this all-too-common problem is, you may not even notice you’re dehydrated until it’s already too late…
Age blunts your thirst
Research shows that, as we age, we lose one of our body’s cues to drink.
As part of a recent study, researchers administered exercise heat tests to 20 men—ten were younger (between 18 and 30 years old) and ten were older (between 54 and 67 years old). All participants abstained from alcohol or strenuous exercise for 24 hours prior. And they drank about 16 ounces of water the night before.
The men received two different exercise sessions, one week apart. Before each session, subjects received an intravenous (IV) saline solution. Then, they cycled for one hour on a stationary bike.
The data showed a marked difference between the body temperature regulation of younger versus older men.
In addition, increases in the salt concentration of the blood didn’t trigger the same dehydration responses—like a reduction in heat loss, an increase in body temperature, and greater thirst—in the older men as they did in the younger men.1
In other words, when older people work out, their bodies don’t adjust in a way that would effectively help prevent further dehydration. This is quite dangerous, as it puts greater strain on the heart—not to mention, introduces a higher risk of heatstroke and exhaustion.
But it’s not just during exercise that a lower sensitivity to dehydration can cause trouble. The study authors point out that even warm environments—like a house with the heat always cranking in the winter—could trigger dehydration without you even realizing it.
(This study looked at men, specifically. But dehydration doesn’t discriminate based on gender—women are just as vulnerable to its effects.)
Of course, age isn’t the only factor that contributes to dehydration. In fact, there’s at least one common problem that can put anyone at risk…
Poor sleep could be to blame
Lack of adequate sleep is an issue I see in adults of all ages. And research now shows that clocking six hours per night—which is under my recommended seven to nine hours of quality shuteye—may leave you with a higher chance of being dehydrated.
Here’s why: As part of yet another recent study, researchers looked at how sleep affected hydration status and risk of dehydration in more than 20,000 U.S. and Chinese adults.
In addition to reviewing survey results, they collected urine samples from the subjects to assess for key hydration biomarkers. Results showed that, in both populations, fewer than six hours of sleep increased the odds of inadequate hydration by as much as 60 percent.2
That’s compared to subjects who routinely get eight hours of sleep per night. And the reason for this was a marked drop in vasopressin—a hormone your body uses to regulate hydration.
Vasopressin release spikes during the sleep cycle. So if your sleep is regularly cut short, chances are good that your body’s simply not making as much as it needs.
The result? Poor hydration… and the loss of energy, focus, and function that comes right along with it.
(It’s also worth mentioning that most research suggests clocking anywhere between six and eight hours is sufficient to ward off the deadly consequences of sleep loss. Meaning six hours of sleep per night isn’t even a significant deficit—yet still introduces these risks.)
So, now that we’ve discussed a few lesser-known causes of dehydration, let’s talk about some detrimental physical effects of not drinking enough water…
Dehydration dulls cognition
As I mentioned earlier, dehydration can affect your brain and memory. And a recent study published in the European Journal of Nutrition shows that once again, older people are at particular risk.
Penn State researchers looked at data from more than 2,500 men and women aged 60 years or older who participated in the Nutrition and Health Examination Survey. The participants were asked to complete three cognitive assessments designed to measure verbal recall, verbal fluency, processing speed, sustained attention, and working memory.
The researchers identified a prominent trend toward lower scores in processing speed, attention, and memory among women who were under-hydrated.3 (Although it’s worth noting that they saw the same trend in those who were overhydrated—a problem that stems from electrolyte imbalances, and a risk that comes with diuretic use and extremely low salt intake.)
For most people, though, inadequate hydration is the main concern. Especially as you age, since your muscle mass and kidney function tend to decline. This lowers water reserves and makes it harder for your body to pick up on hormonal signals that tell you when you’re thirsty.
But that’s not all chronic dehydration can do to your health…
Chronic dehydration harms your heart
As part of new research presented to the European Society of Cardiology, scientists set out to determine whether hydration habits (as measured by sodium concentrations in the blood) could predict future heart failure down the line.
Their study featured nearly 16,000 adults, all part of the Atherosclerosis Risk in Communities (ARIC) study. Subjects were middle-aged (between 44 and 66 years old) at the start of the study, and received evaluations over the course of five visits, until age 70 to 90.
The researchers divided participants into four groups based on their blood sodium concentration at the first two visits. Then, they analyzed rates of heart failure and left ventricular hypertrophy—thickening of the heart’s main pumping chamber, and a precursor to heart failure—at the fifth visit, 25 years later.
In the end, higher blood sodium concentration in midlife was linked with both conditions.4 And that association remained significant, even after researchers adjusted for outside factors—including age, blood pressure, kidney function, blood sugar, body mass index (BMI), and smoking status.
This suggests that good hydration throughout your life could slash your odds of developing heart failure down the line. So if you haven’t been drinking enough water—and unfortunately, most people don’t—I hope this finding helps encourage you to get your drinking habits back on track, sooner than later.
And by “drinking” habits, I mean plain old water. NOT this…
One mistake you don’t want to make
Many of my patients and readers alike report getting “bored” with water. So, much to my horror, they end up turning to soft drinks to quench their thirst instead.
But that’s a HUGE mistake.
In fact, a recently published study in rats showed that rehydrating this way could actually make matters worse. (Even with this being an animal study, you still have to ask yourself whether it’s worth taking the risk. And I hope you’ll agree with me when I quite frankly say: It’s not.)
Researchers split the rats into three different groups: One group received water, another received water with fructose and glucose (forms of sugar), and the third received water with stevia (a natural sweetener).
After repeated heat-induced dehydration, the rats in the second group, that rehydrated with sugar water, ended up more dehydrated—and suffered worse kidney injury—than the rats that drank either plain water or water with stevia.5
(It makes you wonder what all those so-called “sports drinks” are doing to our young athletes. Certainly not helping their kidneys, that’s for sure!)
So now that you know what NOT to drink, let’s revisit the rules of proper hydration…
The basic rules of hydration
No doubt you’ve heard the “eight glasses a day” advice before. But the fact is, that may or may not be enough. To set the record straight, you should be drinking half your body weight in ounces of water each day. So a 150-pound woman would need 75 ounces of water daily, as a rule of thumb.
But if you exercise—and as a reader of mine, I certainly hope that you do!—you need to drink more. For every 30 minutes of physical activity, you should add another eight ounces to your daily total.
And when it comes to caffeinated beverages? Well, for each cup of coffee you drink, your body requires yet another cup of water to make up for it.
I realize that may sound like a lot, but it doesn’t take long to make a habit of it. Drink a full glass of water first thing in the morning, before each meal, and right before bed. That alone will make a pretty big dent in your daily requirement.
You should also keep water with you at all times (or at least, whenever you’re able) and take a big sip every couple of minutes.
And if you find yourself getting “bored” of plain old water, rather than turning to juice or soft drinks, go ahead and jazz up your water instead. Add some real-deal, organic, natural ingredients to it. A few slices of lemon or lime go a long way in adding flavor. You can also use crushed strawberries, cantaloupe, pulverized cucumber, mint, or basil.
Unsweetened, decaffeinated herbal tea is another good option to help your body rehydrate when you want to switch things up. And it’s hard to imagine a cozier way to spend a fall or winter night! My favorite type of herbal tea to enjoy during the cooler months is chamomile. (I enjoy raspberry zinger during spring and summer!)
By making these simple adjustments to your current routine, you’ll meet your daily quota without even thinking about it. But believe me when I say that your body will notice the difference.
Bottom line: It’s far too easy to let proper hydration slip your mind—and doing so can be dangerous for your health. (Especially in the cooler months, when you’re not sweating it out in the sunshine all day, reaching for a cool glass of water.)
So now is the perfect time to readjust your drinking habits—to help prepare your mind and body for the cooler months ahead.
- “Older men need to hydrate even when they are not thirsty.” Medical News Today, 10/12/2020. (medicalnewstoday.com/articles/older-men-need-to-hydrate-even-when-they-are-not-thirsty)
- Rosinger AY, et al. “Short sleep duration is associated with inadequate hydration: Cross-cultural evidence from US and Chinese adults.”Sleep, 2018; DOI: 10.1093/sleep/zsy210
- Bethancourt HJ, et al. “Cognitive performance in relation to hydration status and water intake among older adults, NHANES 2011–2014.”European Journal of Nutrition, 2019; DOI: 10.1007/s00394-019-02152-9
- European Society of Cardiology. “Drinking sufficient water could prevent heart failure.” Science Daily, 08/24/2021. (sciencedaily.com/releases/2021/08/210824104113.htm)
- Garcia-Arroyo FE, et al. “Rehydration with Soft Drink-like Beverages Exacerbates Dehydration and Worsens Dehydration-associated Renal Injury.”American Journal of Physiology – Regulatory, Integrative and Comparative Physiology, 2016; ajpregu.00354.2015 DOI: 10.1152/ajpregu.00354.2015