5 foods you didn’t know could raise your blood pressure

The kidney is an incredible piece of biological machinery. According to the Mayo Clinic, the kidneys filter more than 120 quarts of blood each day, pulling unwanted fluid from cells throughout the body and, in the process, disposing of it through the bladder.

But one extremely tasty and extremely common ingredient can have unwanted effects on that process: salt. While we can’t live without salt (literally—a lack of salt leads to hyponatremia, which causes muscle cramps, nausea, vomiting, and eventually death), most Americans are more likely to consume too much salt than too little, which brings health risks of its own.

Consuming too much salt makes it harder for the kidneys to properly remove fluid, which then builds up in the body and can lead to hypertension over time. The condition stiffens and narrows the blood vessels, which decreases the amount of blood and oxygen that flows to vital organs and, in turn, causes the heart to pump more blood in an attempt to make up for the shortage. All told, too much salt can wreak havoc on the kidneys and heart.

So, what can people do to avoid consuming too much salt? Stay away from foods that are notorious for their high sodium levels, such as frozen, prepackaged meals. In addition, keep an eye out for these 5 foods you might not have known are high in sodium.

Shrimp

Shrimp have numerous nutritional benefits, including high levels of protein. However, many people may not know that this seafood is high in sodium, containing about 111 mg per 100 g serving, according to the USDA.

The shrimp’s saltwater habitat isn’t the only reason it is so high in sodium. Fresh-caught shrimp are typically soaked in a salty brine within minutes of being harvested from the ocean to reduce their temperature more quickly and to prevent ice crystals from forming during the freezing process.

Vegetable juice

While vegetables may be every kid’s worst nightmare, they have been the epitome of the nutrition movement for decades, and many adults are big fans of this food group.

Most fresh veggies are naturally low in sodium. But processed vegetables, like those found in vegetable juice, are a clear exception. Vegetable juice contains about 52 mg of sodium in an 8-oz serving.

Those looking to get the nutrition benefits of vegetables, including fiber, vitamins, and minerals, can eat fresh veggies or turn them into a drink at home by using a blender or food processor.

Canned vegetables

Canned vegetables have plenty of upsides. They’re low in saturated fat and cholesterol and are a good source of protein, thiamin, folate, iron, and vitamins A, C, and K. They’re also high in dietary fiber.

Of course, fresh veggies have all these benefits, too—but they don’t have nearly as much sodium as their canned counterparts. A can of green peas has 310 mg of sodium per serving, or about 13% of the daily recommended intake. Fresh peas, on the other hand, have just 7 mg per cup.

Tortillas

You might think that what you put inside a tortilla is more important than the tortilla itself, since many sauces, cheeses, and meats can be high in sodium. However, that might not always be true if you’re looking to keep blood pressure in check.

While a corn tortilla contains just 13 mg of sodium per 1-oz serving, white flour tortillas have 194 mg for the same serving size.

What about a full-blown taco? Adding chicken, cheese, and lettuce to your tortilla pumps up sodium levels to a whopping 601 mg.

Salad dressing

In a 2009 study of the sodium content in major brands of packaged foods in the United States, researchers found that products in the salad dressing category had the highest mean and median concentrations of sodium per 100 g—1,072 mg and 1,067 mg, respectively.

According to one cooking site, “Drenching salads with bottled dressing is pretty much akin to sprinkling salt on your mixed greens,” as most dressings pack as much as 300 mg to 500 mg of sodium into just one 2-tbsp serving.

Those who want the benefits of mixed greens in their diet without the drawback of high sodium can experiment with making their own dressings by whisking together olive oil and their favorite low-sodium spices.

The takeaway

An estimated 103 million Americans—nearly one-half of all US adults—have hypertension, according to the American Heart Association. This puts them at increased risk for life-threatening complications, such as heart attack, stroke, and kidney failure.

Reducing dietary sodium intake is one of the most effective ways to reduce hypertension and its associated risks, but making that happen means staying vigilant about the foods you eat. While sodium is well known to lurk in processed foods like frozen meals, canned ingredients, and restaurant-cooked meals, it’s also common in many unassuming foods, too.

Next time you head to the grocery store, be sure to keep an eye on the nutrition labels before tossing an item in your cart—sodium might be lurking where you least expect it.