You may have been warned that you’re eating too much salt thanks to a fast-food addiction or abiding love of ramen. But there’s another habit you should be worried about—and not for the reason you expect. Your daily cup (or cups) of joe could be causing your system to flush out so much salt that you’re slowly becoming depleted in this essential nutrient—and potentially damaging your health. Yes, really.
How your caffeine intake affects your sodium levels.
It has been known since 1910 that caffeine increases the urinary excretion of sodium and chloride (aka salt). Animal studies first paved the way, which were soon followed by human studies. Indeed, one study found that 90 mg of caffeine (basically the amount of caffeine found in one cup of coffee) caused 437 mg of extra sodium loss out the urine compared to placebo. When the participants consumed the caffeine equivalent of around four cups of coffee (360 mg of caffeine) there was around a 1,200 mg additional loss of sodium out the urine compared to placebo. To put that amount of sodium loss into perspective, the original limit on sodium intake set by our Dietary Goals back in 1977 was only 1,200 mg per day. No one ever warned the public that we could lose that much sodium by consuming just four cups of coffee.
Some symptoms of salt depletion include dehydration, dizziness, fatigue, dry mouth, and cognitive impairment. These can be potential signs that you’ve had too much caffeine and haven’t replaced the salt that has been lost.
The average person in the United States consumes just over 300 mg of caffeine per day (the amount of caffeine in just over three cups of coffee).
That means if you are following the AHA low-salt advice (consuming less than 1,500 mg of sodium per day) and you may be at risk of salt deficit. And even if you are following the Dietary Guidelines and consuming the upper recommended limit of sodium intake (i.e., 2,300 mg per day or one teaspoon of salt), you could become sodium depleted through the additional salt loss that occurs every day in sweat. In fact, caffeine doesn’t just increase salt loss in the urine—it also increases salt loss in sweat. Talk about a double salt-losing whammy!
Caffeine isn't just in coffee.
Caffeine can also be found in many other places other than coffee, such as nonprescription and prescription drugs, teas, soft drinks, and sports and energy drinks. The fact that most Americans consume caffeine every day again suggests that most of us are probably at risk of salt deficit. I discuss caffeine-induced salt loss as well as numerous other lifestyle factors, disease states, and medications that can cause salt depletion in my book The Salt Fix.
It seems like every day there is another "energy-boosting" beverage that’s even higher in caffeine than the one before it. Our hectic lifestyles continue to force us to succumb to the constant need for more caffeine putting us at further risk of salt loss. So for the java junkies out there, every time you take a sip of coffee you should be thinking about the potential need for more salt. Your liquid "energy booster" may be causing you to be a "salt-waster."
Maybe there’s a good reason you especially crave a salted caramel coffee. That could be your body sending you a message. So for the sake of your health, heed your salt hunger, especially when giving in to your caffeine penchant. If you do consume coffee, add a pinch of mineral salt to counteract the sodium-depleting effects of the beverage, or be sure to add back in some good sodium at other points in your day. It’s worth noting that some individuals might not be at risk of a salt-deficiency and should consult a medical professional before upping their sodium intake, but by and large, my research proves that this is a genuine issue plaguing our country.