Salt: You always hear it's bad for you in large quantities, but probably think it won’t affect you. Well, think again. A new study shows that as many as half a million lives could be saved if we reduced our daily salt intake by just a fraction of a teaspoon.

The study, published in the American Heart Association’s journal Hypertension, showed that a steady decrease in salt consumption -- reaching a 40% reduction over a period of 10 years -- would extend the lives of between 280,000 and 500,000 people. The decrease in salt intake would prolong so many lives by reducing the risk of hypertension, heart disease and stroke -- the leading causes of death in the United States.

The average American consumes 3,600 milligrams of sodium on a daily basis. Most of the sodium we consume is in the form of salt, and that daily consumption figure corresponds to less than 1½ teaspoons of salt. According to the Centers for Disease Control and Prevention (CDC), about 90% of Americans ingest more than the recommended daily amount of sodium, which is no more than 2,300 milligrams. But there are certain people who should limit their consumption to even less than that -- about 1,300 milligrams a day, according to the CDC. That group include people over 51 years old, African-Americans, people with high blood pressure, people with diabetes and people with chronic kidney disease. The CDC says about one in six adults should aim for only 1,500 milligrams a day.

What’s so bad about sodium? It can increase blood pressure and a person's risk for a heart attack or stroke. The prevalence of high blood pressure (hypertension) increases with age, and a family history of the problem increases the likelihood that children will also develop high blood pressure.

So what can you do? Avoid consuming too much of the foods that are high in sodium, and try choosing some low-sodium options whenever possible. The CDC says it's better to choose fresh, frozen (no sauce), or no salt added canned vegetables. It also helps to be familiar with terms that indicate higher sodium content, such as "pickled," "cured," "brined" and "broth." The CDC also offers ways that we as a country can reduce our sodium intake overall.

For more information, or if you need to get on a low-sodium diet, check out the CDC’s guide to sodium.