It is important to have a proper balance of salt (sodium chloride) in one’s diet. Sodium, which is 40 percent of salt, is essential to life because it regulates the fluid balance of cells and plasma. Too little sodium in the body can result in dehydration because the cells are unable to retain water. On the other hand, too much sodium may increase the risk of high blood pressure (hypertension). Also, certain groups of people are higher risk for certain conditions if their salt consumption is too high. Overweight people who eat too much salt are at greater risk of heart disease or stroke and people with high blood pressure are at greater risk of damaging their kidneys.

The body only requires about half a gram of sodium per day, and the American Heart Association recommends that people consume no more than 2.3 grams (about 1 teaspoon of salt per day). However, the average American consumes at least nine grams of sodium per day, with many Americans eating 6 to 18 grams on a daily basis. Therefore, most Americans need to reduce their salt intake. Strategies for reducing salt/sodium intake can include eating more fresh fruits and vegetables, avoiding processed foods and salty snacks and cooking with little or no salt.

Lifestyle changes, including dietary adjustments, can help prevent or delay medical conditions such as high blood pressure. Some studies have suggested that reducing salt intake can reduce an individual’s risk of developing heart disease by up to 25 percent. In turn, lowering and maintaining normal blood pressure and decrease the risk of heart-related conditions.

The most significant consequence that excess salt has on the heart is high blood pressure (hypertension). Too much salt can lead to water retention in the blood. Normally, the kidneys flush this excess water from the body. However, kidneys that are not functioning properly are unable to expel the excess fluid sufficiently, which will lead to fluid retention. This increases the volume of blood being pumped through the blood vessels and can lead to high blood pressure.

In an effort to pump the extra fluid through the body, the heart may also become dilated or enlarged. The extra volume of fluid may also leave the bloodstream and enter body tissues, causing swelling (edema) in the parts of the body where it builds up. 

If an individual already has high blood pressure, kidney function may slow down and excess salt and fluid will collect in the body, adding further to the hypertension problem. Hypertension is a risk factor for heart attacks, kidney disease and strokes.

The National Heart, Lung and Blood Institute (NHLBI) clinical practice guidelines recommend and encourage lifestyle changes to prevent high blood pressure. These include losing excess weight, becoming physically active, limiting alcoholic beverages and following a heart-healthy diet, including cutting back on salt and other forms of sodium. The guidelines recommend that Americans follow the Dietary Approach to Stop Hypertension (DASH) eating plan, rich in fruits, vegetables and nonfat dairy products.

Although sometimes controversial, the long-standing argument against the excessive use of salt has gained strength over the last several years. Studies have indicated that higher salt intake increases an individual’s blood pressure. In turn, higher blood pressure is linked to an increased risk of coronary heart disease, stroke and congestive heart failure. By reducing salt intake, individuals may prevent of reduce the onset of high blood pressure and associated medical conditions.

Other studies have suggested that salt intake increases the risk not only of high blood pressure, but also of heart disease, heart failure and stroke in overweight men and women. In addition, studies have suggested that people with salt- sensitivity (a measure of blood pressure change in response to salt intake) have a greater risk of medical problems with high salt consumption.

Research has shown that African Americans tend to be more salt-sensitive than white Americans, and as many as 80 percent of African Americans with high blood pressure may be salt-sensitive. While these studies have not identified whether people are genetically predisposed to be salt-sensitive, they have shown that all individuals will positively benefit from a reduced-salt diet.

About 75 percent of all salt consumed in the United States comes from salt added in the processing and manufacturing of foods. Only 12 percent of salt in the average occurs naturally in foods.

The amount of sodium found in foods in the American diet varies according to the specific item. Certain foods typically have higher sodium content due to their preparation. For example, a one-ounce serving of bread can have 95-210 mg of sodium while the same size serving of pretzels can have 290 to 560 mg of sodium.

The average American, according to the American Heart Association (AHA), consumes six to 18 grams of salt daily. However, the 2005 Dietary Guidelines for Americans established by the United States Dietary Association (USDA) recommends restricting daily sodium (salt) intake to 2300 milligrams (2.3 grams) or less – no more than about a teaspoon of table salt. This amount is more than half the amount typically consumed by Americans.

Because a small amount of sodium is vital for maintaining healthy body function, it is possible to have too little salt (sodium chloride). Symptoms of sodium deficiency include weakness, cramping, headache and (in severe cases) shock. However, this condition is rarely experienced by anyone other than athletes who have been sweating profusely for long periods of time, or people who regularly use diuretics or laxatives.

The widespread, liberal use of salt in the foods people eat is one of the difficulties in keeping sodium intake low in a typical diet. Most of the sodium (75 percent) in the average American’s diet comes from the manufacturing of processed foods. Since the body only requires about 500 milligrams per day, naturally occurring sodium in fruits and vegetables may be enough to sustain good body function. However, sodium in the diet quickly adds up when salt is added in the following ways:

• Cooking
• As a table seasoning (salt shaker)
• In restaurant foods
• In processed, prepackaged or prepared foods purchased in the grocery store (e.g., soups, chips, cheese and ice cream)
• As a natural preservative for meats and vegetables
• Over-the-counter medications

The Food and Drug Administration (FDA) has established guidelines for labeling sodium content in foods. For foods to use a specific claim, manufacturers must adhere to the following guidelines:

• “Sodium-free” or “salt-free” foods contain less than 5 milligrams sodium per serving.
  
  
• “Very low-sodium” foods contain less than 35 milligrams sodium per serving.
  
  
• “Low-sodium” foods contain 140 milligrams or less sodium per serving.
  
  
• “Reduced-sodium” foods usually have a sodium level that has been reduced by 25 percent.  Some reduced-sodium products such as soy sauce or canned soups can still contain significant amounts of sodium.
  
  
• “Unsalted” or “no salt added” can be used on foods that have been made without the normal amount of salt typically used in preparation. The item still may contain sodium that is naturally found in the food.

In addition, foods that claim to be “healthy” must not exceed 360 mg of sodium per reference amount and “meat type” products must not exceed 480 mg sodium per reference amount.

There are a number of strategies that can be used to reduce salt intake in the diet, including:

• Avoid prepared foods (e.g. frozen entrees, pizzas) as much as possible. If these foods are part of the diet, choose the brand that has the lowest sodium content and limit these items in the diet.
  
  
• Read food labels and become aware of which foods have the highest sodium content. Also, look for reduced sodium options among selected foods (e.g. canned soups, vegetables).
  
  
• Do not add additional salt to prepared foods. It may help to remove the salt shaker from the table.
  
  
• Choose meats with less naturally occurring salt, such as turkey or chicken. Also, do not use sauces with high salt content with meat (e.g. soy sauce, marinades).
  
  
• Use seasonings and spices other than salt (e.g., choose garlic powder over garlic salt). Learn to use herbs and spices to season foods instead of salt.
  
  
• Replace canned, frozen and other processed foods with fresh fruits and vegetables.
  
  
• Limit consumption of salty snacks like pretzels, peanuts and potato chips.
  
  
• Request that restaurants cook with little or no salt or monosodium glutamate (MSG), which is often used in commercial Chinese cooking.
  
  
• Use margarine or unsalted butter rather than regular butter.
  
  
• Select low-fat, low-sodium cheese and yogurt.

Eat bananas and other potassium-rich foods. Studies have shown that foods rich in potassium can reduce the effect of salt on blood pressure. Potassium may also reduce the risk of kidney stones.

Preparing questions in advance can help patients have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following questions about salt and your heart:

1. How much sodium should be in my daily diet?
   
   
2. Which signs might indicate I have a problem from too much sodium?
   
   
3. Do I need to worry about sodium if I don’t have high blood pressure?
   
   
4. Will salt reduce the effectiveness of my blood pressure medicine?
   
   
5. How can I determine how much sodium I am getting every day?
   
   
6. Can I use a salt substitute?
   
   
7. Is there a specific diet I should follow?
   
   
8. Are there any over-the-counter medications that I should avoid?
   
   
9. Can you recommend a dietician to help me with my diet?
   
   
10. If I reduce my sodium intake, how quickly can I expect to see improvement in my blood pressure?