Salt is essential to our bodies, but too much can be deadly, especially when it leads to high blood pressure and other illnesses.

According to Dr. Michael Greger, founder of  NutritionFacts.org, for the first 90% of our evolution humans ate less than a quarter teaspoon of salt daily. When salt was introduced to preserve foods, blood pressures soared, leaving us with the current hypertension epidemic.

Special: Heart Surgeon's Secret to Healthy Blood Pressure

More than 119.9 million Americans suffer from high blood pressure and prescription drugs used to control hypertension can have potentially dangerous side effects.

Greger profiles the Yanomami people of the Amazon rainforest, who have the lowest salt intake reported in the world. While in the U.S. blood pressure typically rises with age, in this Amazon culture they keep a steady blood pressure of 100 over 60, and it doesn’t change with aging.

“Excess sodium can increase your blood pressure and your risk of heart disease and stroke,” asserts the Centers for Disease Control and Prevention (CDC). “Together, heart disease and stroke kill more Americans each year than any other cause.”

Greger believes that by simply lowering our intake of sodium we can eliminate hypertension as we age.

But how do you know if you are consuming too much salt?

According to Health, eating too much salt can lead to:

• Bloating and water retention. Your body retains extra sodium after consuming a high-salt meal so when you drink water, you retain the moisture, causing an unpleasant bloating. This can also lead to edema, or generalized swelling of the body, particularly noticeable in the hands and ankles.

• Elevated blood pressure. With an increase in the amount of fluid in the body, blood pressure can rise due to a higher blood volume. People who are more sensitive to salt may develop hypertension, which left untreated can lead to heart failure, stroke or kidney disease.

• Increased thirst. When you eat foods that are high in salt, you become thirstier because your body is experiencing an imbalance of salt and water, says Health. Drinking more water will also increase the need to urinate more frequently.  

• Kidney stones. If you eat lots of salt and do not consume enough water, you raise the risk of developing kidney stones. Drinking water helps calcium travel through your system so that it doesn’t form stones in the kidneys.

• Stomach cancer. Studies have shown a link between excess salt intake and stomach cancer. While scientists don’t know the exact cause and effect, they suggest limiting salt intake to be on the safe side.

The Dietary Guidelines for Americans recommends consuming less than 2,300 milligrams of salt daily, which is about the equivalent of one teaspoon. Studies vary on just how much salt individuals need but the general advice given by healthcare professionals is to limit the amount of processed foods we consume and go easy on the saltshaker. Your doctor can help provide more individualized guidelines.