Salt contains sodium, a mineral the body needs in small amounts for nerves, muscles, and fluid balance. Too much sodium can make the body hold extra water, which increases the amount of fluid in the bloodstream. This can raise blood pressure and make the heart and blood vessels work harder.
Learning how to spot high-sodium foods helps students make healthier choices every day.
The kidneys help control sodium and water levels by filtering the blood and sending extra waste into urine. When sodium intake stays high over time, the kidneys may have to work harder to keep balance. Many high-sodium foods do not taste extremely salty, including bread, pizza, soups, sauces, deli meats, and packaged snacks.
Reading nutrition labels and choosing fresh or lower-sodium foods can lower sodium intake without giving up flavor.
Key Facts
- Table salt is sodium chloride, written as NaCl.
- About 40% of table salt by mass is sodium.
- 1 teaspoon of table salt contains about 2,300 mg of sodium.
- Daily sodium limit for many people is about 2,300 mg, and lower goals may be advised for some individuals.
- Blood pressure is written as systolic/diastolic, such as 120/80 mmHg.
- Reducing sodium often means choosing foods with less than 140 mg sodium per serving, which is considered low sodium.
Vocabulary
- Sodium
- Sodium is a mineral and electrolyte that helps nerves, muscles, and fluid balance work properly.
- Salt
- Salt is a compound called sodium chloride that is commonly used to season and preserve food.
- Blood pressure
- Blood pressure is the force of blood pushing against the walls of blood vessels.
- Kidneys
- The kidneys are organs that filter the blood and help control water, salt, and waste levels in the body.
- Nutrition label
- A nutrition label is the information panel on packaged food that lists nutrients such as sodium per serving.
Common Mistakes to Avoid
- Thinking only salty-tasting foods are high in sodium is wrong because many packaged foods, breads, sauces, and soups can contain a lot of sodium even if they do not taste very salty.
- Ignoring serving size is wrong because the sodium number on a label is usually for one serving, not always the entire package.
- Assuming sea salt is much healthier than table salt is wrong because both contain sodium and can raise sodium intake when used in large amounts.
- Trying to remove all sodium is wrong because the body needs some sodium for normal nerve, muscle, and fluid functions.
Practice Questions
- 1 A soup has 760 mg of sodium per serving and the can contains 2 servings. How many milligrams of sodium are in the whole can?
- 2 A student eats 1,200 mg of sodium at lunch and 950 mg at dinner. If the daily limit is 2,300 mg, how many milligrams remain for other foods that day?
- 3 A snack food has 90 mg of sodium per serving, but the package contains 4 servings. Explain why checking the serving size matters before deciding whether the snack fits a low-sodium eating plan.