Salt can raise blood pressure, putting stress on the circulatory system and increasing the risk of heart disease and stroke. While blood pressure is determined by many factors, including genetics and environment, one of the most important factors you can control is how much salt you eat, according to Willie Lawrence, a cardiologist in Kansas City, Missouri, and a spokesperson for the American Heart Association. “By limiting salt intake, one can reduce their blood pressure and therefore their risk of developing heart disease or stroke,” Lawrence says. The AHA recommends limiting salt intake to 1,500 mg a day. Avoiding the saltshaker isn't enough to reach that goal. You need to know the hidden sources of sodium. Take our quiz and discover eight shocking, hidden sources of salt.

Skinny Pop popcorn (3/4 cup) OR grocery store rotisserie chicken (4 ounces)?

Answer: The chicken. “We don't necessarily think of chicken as salty but rotisserie chicken is often injected with salt water to make the chicken juicy and more flavorful,” says Danielle Allen, a registered dietitian in Hopkinton, Massachusetts. “The high salt content also helps preserve the meat.” As a result, rotisserie chicken has around 320 mg of sodium compared with 75 mg for the popcorn. “Baking a chicken breast at home with oil, herbs and seasonings other than salt can cut your sodium by more than 200 milligrams,” she says. Just avoid buying chicken that's been “enhanced” with broth, which boosts sodium levels.

Schweppes club soda (12 ounces) OR Blue Diamond roasted salted almonds (1 ounce, about 23 almonds)?

Answer: The club soda. It contains 95 mg sodium versus 85 mg for the nuts. “The club soda contains sodium bicarbonate (baking soda) and sodium chloride (table salt) to enhance taste and to neutralize the acidity,” says Jennifer Glockner, a registered dietitian in Los Angeles and creator of the e-book series Smartee Plate. If you don't want to drink plain water, try sparkling water such as San Pellegrino, which has only 1 mg sodium per ounce, Glockner suggests.

Campbell's Condensed Chicken Noodle Soup (10.75-ounce can) OR a bag of potato chips (8 ounces)?

Answer: The soup. It contains a whopping 2,225 mg of sodium, compared with the chips’ hefty 1,300 mg. “People often see the tiny can of Campbell's and assume it is one serving, but there are 2.5 servings per container,” Allen says. “A great alternative for those who don't want to make their own soup is Campbell's Low Sodium Chicken With Noodles, which uses potassium chloride as a salt substitute and contains only 120 milligrams of sodium per can."

Land O'Lakes salted whipped butter (1 Tbsp.) OR Best Foods Real Mayonnaise (1 Tbsp.)?

Answer: The mayo. It checks in at 95 mg of sodium compared with 50 mg for the butter. “They both contain added salt but the mayo also has a preservative that contains sodium,” Glockner says. “As an alternative sandwich spread, consider using a mashed-up slice of avocado, which only contains a negligible amount of sodium."

McDonald's Chicken McNuggets (10 pieces) OR V8 Vegetable Juice (12 ounces)?

Answer: The juice. “The V8 contains three servings of veggies in 12 fluid ounces, which could be considered healthy,” Glockner says. “However, it contains 960 milligrams of sodium from added salt — 40 percent of the maximum daily allowance of 2,300 milligrams of sodium.” In comparison, the nuggets contain 900 mg of sodium. Try V8's low-sodium option instead (200 mg per 11.5 ounces) or eat your veggies and drink water instead, she recommends.

Prego Basil Pesto Italian Sauce (1/4 cup) or Prego Tomato Basil Garlic Italian Sauce (1/4 cup)?

Answer: The pesto. “Not only does the pesto have more than two times the amount of sodium [590 mg versus 210 mg], it's also higher in saturated fat,” says Allison Knott, a registered dietitian in New York City. “If you're looking for a lower-sodium pasta sauce, choose a tomato-based option and compare brands to find the one that is the lowest in sodium per serving. Adding cooked vegetables can also help you ‘stretch’ the sauce, lowering total sodium per serving."

Subway Oven Roasted Chicken Breast on Spinach Wrap OR Subway 6-inch Oven Roasted Chicken Sandwich?

Answer: The chicken wrap — with 1,350 mg of sodium. “Much of the sodium difference is attributed to the difference in bread,” Knott says. The spinach wrap alone has 780 mg of sodium — more than the amount in the entire chicken sandwich (560 mg).

Bonefish Grill Cobb Salad with Wood Grilled Shrimp OR Bonefish Grill Blackened Baja Fish Tacos with Corn Tortillas (two)?

Answer: The Cobb salad — with 2,220 mg of sodium, compared with 720 mg for the tacos. You can probably guess that cheese, dressing and bacon make a Cobb salad pretty salty. “But you may be surprised to learn that shrimp can also be a significant source of sodium if it has been processed with a salty brine,” Knott says. To lower sodium, opt for an alternative seafood like grilled salmon or tuna and get a cooked vegetable side instead of a high-sodium salad, she says.