The minerals in your blood — also called electrolytes — are essential for health, but they need to be in balance. "Any upset in the delicate balance of electrolytes can cause a headache," says Michael Doerrler, DO, a headache specialist at Loyola University Medical Center in Chicago.
Sodium is a mineral that's been tied to headaches in more than one way. It's the key element of table salt, which also includes the mineral chloride, and research suggests that an overly salty diet can lead to headaches. Also, sodium has been linked to high blood pressure — a condition that has ties to headaches.
High Blood Pressure Headache
"Sodium can cause high blood pressure or make it worse," says Dr. Doerrler, who's also an assistant professor of neurology at Loyola University Medical Center. "High blood pressure can trigger a headache, and a headache can trigger blood pressure. It can be a vicious cycle."
The link between too much sodium and high blood pressure is strong. Sodium is a mineral that draws water to itself. When you have too much sodium in your blood, it draws water from your body into your blood vessels. The effect is like what happens when you turn up the water in a garden hose: The pressure goes up. This time, though, it's your blood pressure.
A high blood pressure headache can occur if your blood pressure numbers are higher than 180 over 110. The first number is the systolic pressure, the pressure in your blood vessels when your heart beats. The second number is diastolic pressure, when your heart relaxes between beats.
The reading that could lead to a headache, though, represents unusually high blood pressure, which means that high blood pressure from too much sodium is not a very common cause of headache.
However, if you do have a high blood pressure headache, it will probably feel as if there's a tight band around your head. That's why it's sometimes called a "hairband headache." If you have a headache caused by high blood pressure, you need to work with your doctor to get your blood pressure under control.
Too Much Salt Headache
A study from Johns Hopkins University suggests that too much salt in your diet can cause headaches, even if you don't have high blood pressure.
The study, published in December 2014 in the medical journal BMJ Open, found that people who consumed the most salt had one-third more headaches than people who consumed half as much salt, as the the National Headache Foundation points out. It determined that the increase in headaches was directly related to the amount of salt and that it did not matter whether participants had high blood pressure. The researchers noted that reducing salt in your diet might help prevent headaches.
Eat Less Salt to Reduce Headaches
If you are like most Americans, you eat too much salt. In the BMJ Open study, the high-salt group consumed about 8 grams of salt every day during the study. That's less than 2 teaspoons. But since the majority of most people's salt intake comes from prepared foods and packaged foods, you don't need to add much from your salt shaker to get up to the headache level.
The American Heart Association recommends no more than 1 teaspoon of salt a day for average adults who do not need to lower salt for a medical reason. If you can stay near that level, you may have fewer headaches. To accomplish that, though, you need to read food labels carefully, checking for sodium content, and resist the urge to salt your food.
"Reducing salt may reduce headaches, but it will also have other big benefits, like reducing your risk of high blood pressure, heart disease, stroke and kidney disease," says Dr. Doerrler.
"If you are having three or more headaches per week, you should check in with your doctor," he says. You may need to get your blood pressure checked. Even if your blood pressure is fine, talk to your doctor to see if you need to lower the amount of salt in your diet.
Is This an Emergency?
- BMJ Open: "Effects of Dietary Sodium and the DASH Diet on the Occurrence of Headaches: Results from Randomised Multicentre DASH-Sodium Clinical Trial"
- National Headache Foundation: "Cut Back on Salt to Decrease Headaches"
- American Heart Association: “Get the Scoop on Sodium and Salt”
- National Headache Foundation: “The Complete Headache Chart”
- American Heart Association: "A Grain of Salt"