Have you ever woken up in the morning, after a night of not drinking at all, and felt the familiar pangs of a hangover? Headache, nausea, dry mouth—yep, all the usual suspects are present and ready to ruin your day. But, like, how? You really, truly didn’t even have a drop to drink.

If you indulged in a particularly sodium-rich meal the night before (like a decadent—and soy sauce-heavy—sushi tasting menu), chances are, you’ve got yourself a salt hangover. “The main reason behind a ‘salt hangover,’ really, is dehydration,” says internist Albert Ahn, MD. “Having too much salt in the diet draws water into circulating volume, leading to increased urination. Without replenishing this water loss, you can quickly become dehydrated, especially overnight.”

Sound familiar? Well, it is basically what happens when you drink too much. (Ever notice how curiously long bathroom lines at bars seem to be?) Alcohol contains ethanol, which is a diuretic, so it makes you pee. If you aren’t replenishing that volume, then voilà: Hello, dehydration and the searing headache it can bring.

“The main reason behind a ‘salt hangover,’ really, is dehydration.” —Albert Ahn, MD

People with diets high in salt are obviously more prone to these effects, and if you deal with certain health conditions, like diabetes or issues with the kidneys, you also may be more prone to dehydration—and thus should take extra care with your salt intake. Dr. Ahn adds that older patients and women might be more sensitive to changes in hydration and blood pressure as well. (As if we needed another reason to back up why being a woman is tough as nails….)

The main way to cure a salt hangover is, of course, rehydration. But you may also be able to cut the problem off before it starts. “If you are feeling thirsty or noticing that your urine is darker or more yellow, you are already behind on staying hydrated,” Dr. Ahn says. “With a normal diet, just water is needed to rehydrate.”

An easy way to stay on top of your water game? Since salt lingers in prepared and packaged foods, swapping those options out for whole foods (or healthy canned soups that aren’t loaded with the salt) is a way to nix excess sodium from your diet. This also packs the added benefit of helping to hydrate you, since certain fruits and veggies, like watermelon and (super-buzzy) celery, are so high in water content.

And remember, there are also long-term complications that can arise with a high-salt diet. “It can lead to swelling and edema in the legs and hypertension,” Dr. Ahn says. “There has also been a link between high-salt diets and decreased cognitive function.”

So evading that achy morning-after feeling isn’t the only reason to temper your high-salt habit—the rest of your life is at play here, too.

Get hydration tips from a water sommelier, because yes, that’s a real thing. Also, beware of cold weather getting in the way of your best water-drinking efforts.