Tuna and Blood Pressure: Do's and Don'ts

Whether you're rustling up a tuna salad or a classic tuna melt, a can of the versatile fish is always handy for a quick and tasty meal. But if you're on a high blood pressure diet — that is, you're trying to improve your blood pressure numbers a bit — you may wonder if canned tuna fits the bill.

"Is tuna good for blood pressure?" is a valid question, given that the fish swims in salty sea water. The American Heart Association (AHA) says that salt — or more specifically, the sodium it contains — is an ingredient people need to cut down on to keep blood pressure in check. The good news, though, is that it's perfectly fine for people with high blood pressure to eat tuna, as long as you follow some simple guidelines.

Purchasing canned tuna without added salt is the obvious thing to do, but labels can be misleading. "You might think that tuna canned in water means tuna, water and nothing else, but salt is usually added if you look at the ingredients list," says Vandana Sheth, RDN, CDE, a dietitian-nutritionist based in Torrance, California.

The U.S. Department of Agriculture (USDA) says that 3 ounces of white (albacore) water-packed tuna has 320 milligrams of sodium. That's about one-seventh of the 2,300 milligrams maximum daily recommendation set by the 2015-2020 Dietary Guidelines for Americans.

"To get the lowest sodium tuna available, you need to look for a label that specifically says either 'reduced sodium' or 'no salt added.'" Sheth says. The USDA says 3 ounces of white tuna in water without added salt has a negligible 42.5 mg of sodium.

If you can't find no-added-salt tuna, another option is to wash the excess salt from the standard variety. "Rinsing the broken-up tuna chunks in a sieve under running tap for about three minutes can reduce the sodium by up to 80 percent," Sheth says.

​Read more:​ Chunk Light Tuna Vs. Albacore

The National Heart, Lung, and Blood Institute says tuna can easily fit into a high blood pressure diet. The organization's DASH (Dietary Approaches to Stop Hypertension) eating plan includes it.

What's more, the AHA lists albacore tuna as a heart-healthy fatty fish, rich in omega-3 fatty acids. It recommends eating two servings of fish — ideally a fatty variety — each week, while being mindful of its mercury content.

Mercury levels are low in canned light tuna, according to the U.S. Food and Drug Administration, so eating two to three servings a week is fine. However, levels are higher in albacore (white) and yellowfin tuna, so stick to one portion a week of those.

You'll also get a good boost of selenium from all types of canned tuna, an analysis in the October 2012 edition of ​Food Chemistry​ found. The potential benefit to health? Higher blood selenium levels correlate with lower prevalence of stroke, according to a May 2019 ​Journal of the American Heart Association​ study.

Putting together a diet of foods that lower blood pressure isn't just about watching sodium. Eating more potassium-rich foods is also vital, Harvard Medical School says, because the mineral relaxes your blood vessel walls, reducing the pressure inside them.

Eating less sodium and more potassium could translate into fewer heart attacks, strokes and deaths from heart disease. Teaming tuna with beans in a salad is an example of how to skew the sodium-potassium ratio in favor of your health.

Fruits, vegetables, beans and some seeds are all good potassium sources. Bananas (with 487 milligrams of potassium in a large one) are often hailed as a rich source of the mineral, but there are even better options. For example, a large, baked sweet potato has 855 milligrams of potassium, per the USDA, and a cup of canned, low-sodium white beans has more than 928 milligrams, the USDA notes.

Most Americans don't even get half the recommended intake of potassium, which is 4,700 milligrams a day, but including several potassium-rich foods in your diet every day will help you reach your target.

​Read more:​ 8 Foods That Pack in More Potassium Than a Banana