Sodium is an important mineral that performs many essential functions in your body.
It’s found naturally in foods like eggs and vegetables and is also a main component of table salt (sodium chloride).
Though it’s vital to health, dietary sodium is sometimes limited under certain circumstances.
For example, a low-sodium diet is commonly prescribed to people with certain medical conditions, including heart failure, high blood pressure, and kidney disease.
This article explains why a low-sodium diet is necessary for some people and reviews the benefits, risks, and foods to avoid and eat.
What is a low-sodium diet?
Sodium is an essential mineral in many important bodily functions, including cellular function, fluid regulation, electrolyte balance, and blood pressure.
Because this mineral is vital to life, your kidneys tightly regulate its levels based on bodily fluids’ concentration (osmolarity).
Sodium is found in most foods you eat — though whole foods like vegetables, fruits, and poultry contain much lower amounts.
Plant-based foods, like fresh produce, generally have less sodium than animal-based foods, such as meat and dairy products.
Sodium is most concentrated in processed and packaged foods like chips, frozen dinners, and fast food, where salt is added during processing to enhance flavor.
Another major contributor to sodium intake is adding salt to food when preparing meals in your kitchen and as a seasoning before eating.
A low-sodium diet limits high-sodium foods and beverages.
Healthcare professionals typically recommend these diets to treat conditions such as high blood pressure or heart disease.
Although there are variations, sodium intake is generally kept to less than 2–3 grams (2,000–3,000 mg) per day.
For reference, one teaspoon of salt contains about 2,300 mg of sodium.
When following a low-sodium diet, foods high in sodium must be limited or completely avoided to keep your sodium intake under the recommended level.
Summary: Healthcare professionals recommend low-sodium diets to treat certain medical conditions. Sodium levels are typically restricted to less than 2–3 grams (2,000–3,000 mg) daily.
Why are low-sodium diets prescribed?
Low-sodium diets are some of the most commonly used diets in hospital settings.
Research shows that restricting sodium may help control or improve certain medical conditions.
Kidney diseases, such as chronic kidney disease (CKD) or kidney failure, negatively impact kidney function.
When your kidneys are compromised, they can’t effectively remove excess sodium or fluid from your body.
If sodium and fluid levels become too high, pressure builds in your blood, which can cause further damage to already compromised kidneys.
For these reasons, The National Kidney Foundation recommends that all people with CKD restrict their sodium intake to less than 2 grams (2,000 mg) daily.
A review of 11 studies in people with CKD found that moderate sodium restriction significantly reduced blood pressure and protein in the urine (a marker of kidney damage).
High blood pressure
High blood pressure is a risk factor for various conditions, including heart disease and stroke.
A high-sodium diet has been linked to elevated blood pressure.
For example, a recent study of 766 people demonstrated that those with the highest urinary sodium excretion had the highest blood pressure levels.
Many studies have shown that reducing salt intake may help decrease high blood pressure in people with elevated levels.
A review of six studies in more than 3,000 people showed that salt restriction lowered blood pressure in adults — with the strongest impact observed in those with high blood pressure.
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Salt sensitivity of people with high blood pressure varies widely, and certain subgroups — such as African Americans — tend to be more impacted by high-salt diets.
Nevertheless, low-sodium diets are commonly prescribed as a natural treatment for all people with high blood pressure.
Low-sodium diets are commonly recommended for those with heart conditions, including heart failure.
When your heart is compromised, kidney function declines, which can lead to sodium and water retention.
Eating too much salt could cause fluid overload in people with heart failure and lead to dangerous complications, such as shortness of breath.
Regulatory agencies recommend that people with mild heart failure limit their sodium intake to 3,000 mg daily. In comparison, those with moderate to severe heart failure should reduce their intake to no more than 2,000 mg daily.
However, while many studies have shown that low-sodium diets benefit those with heart failure, others have noted that non-restrictive diets lead to better outcomes.
For example, a study of 833 people with heart failure found that a sodium-restricted diet with less than 2,500 mg per day was associated with a significantly higher risk of death or hospitalization than unrestricted-sodium diets with 2,500 mg or more per day.
Summary: Low-sodium diets are commonly prescribed to people with kidney disease, heart disease, or high blood pressure to manage symptoms and prevent complications.
Benefits of a low-sodium diet
Following a low-sodium diet may benefit health in several ways.
A low-sodium diet may reduce blood pressure
As stated above, a low-sodium diet may help decrease blood pressure.
Studies have shown that transitioning to a low-sodium diet can lead to small yet significant changes in blood pressure, especially in people with elevated levels.
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A review of 34 studies demonstrated that a modest reduction in salt intake for four or more weeks led to significant reductions in blood pressure in people with both high and normal levels.
In the participants with high blood pressure, the average systolic and diastolic blood pressure reduction was 5.39 mmHg and 2.82 mmHg, respectively.
By comparison, people with normal levels noticed a 2.42 mmHg reduction in systolic blood pressure (the top number of a reading) and a 1.00 mmHg reduction in diastolic blood pressure (the bottom number of a reading).
A low-sodium diet may help decrease cancer risk
High-salt diets have been linked to certain types of cancers, including of the stomach.
A review of 76 studies in more than 6,300,000 people found that for every five-gram increase of dietary salt per day — from high-salt processed foods — the risk of stomach cancer increased by 12%.
Research has shown that high-salt diets can damage the mucosal lining of your stomach and increase inflammation and the growth of H. Pylori bacteria — all of which may raise stomach cancer risk.
On the other hand, a diet low in high-sodium processed foods and rich in fruits and vegetables is associated with a lower risk of stomach cancer.
A low-sodium diet may improve diet quality
Many unhealthy foods are extremely high in sodium.
Fast food, packaged items, and frozen meals are not only loaded with salt but are also high in unhealthy fats and calories.
Frequent consumption of these foods has been linked to health conditions such as obesity, diabetes, and heart disease.
These high-salt foods are off-limits on a low-sodium diet, which may improve your overall diet quality.
Summary: Following a low-sodium diet may decrease blood pressure, lower your risk of stomach cancer and improve diet quality.
Foods to avoid on a low-sodium diet
The following foods are high in sodium and should be avoided on a low-sodium diet:
- Fast food: Burgers, fries, chicken fingers, pizza, etc.
- Salty snack foods: Salted pretzels, chips, salted nuts, salted crackers, etc.
- Frozen dinners: Frozen meat dishes, frozen pizza, etc.
- Processed meats: Bacon, sausage, lunch meats, and hot dogs.
- Salted, canned products: Vegetables, pasta, meats, fish, etc.
- Salty soups: Canned soups and packaged soups.
- Cheese and dairy: Cheese, cheese spreads, cottage cheese, buttermilk, salted butter, and cheese sauce.
- High-sodium baked goods: Salted rolls, salted bagels, croutons, and crackers.
- Baking mixes: High-sodium waffle, pancake, or cake mixes.
- Boxed meals: Macaroni and cheese, pasta, rice, etc.
- High-sodium side dishes: Stuffing, boxed au gratin potatoes, hash browns, and rice pilaf.
- Sauces and condiments: Gravy, soy sauce, commercial tomato sauce, salsa, and salad dressing.
- Pickled vegetables: Pickles, olives, and sauerkraut.
- Certain drinks: Regular vegetable juice, juice blends, and salty alcoholic beverages.
- Seasonings: Salt and salt blends.
Though certain foods like vegetables and unprocessed meats naturally contain small amounts of sodium, it’s insignificant compared to the amount added to commercially prepared foods.
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The best way to avoid high-sodium foods is to restrict salty snack foods, fast food, and packaged meals.
Summary: Processed meats, cheese, frozen meals, fast foods, and salty condiments are some of the highest sodium foods and should be avoided on a low-sodium diet.
Low-sodium foods to enjoy
If you follow a low-sodium diet, choosing foods naturally low in sodium or containing limited amounts of added salt is important.
The following foods are low in sodium and safe to eat on a low-sodium diet:
- Fresh and frozen vegetables (without sauces): Greens, broccoli, cauliflower, peppers, etc.
- Fresh, frozen, or dried fruits: Berries, apples, bananas, pears, etc.
- Grains and beans: Dried beans, brown rice, farro, quinoa, and whole wheat pasta.
- Starchy vegetables: Potatoes, sweet potatoes, butternut squash, and parsnips.
- Fresh or frozen meat and poultry: Chicken, turkey, beef, or pork.
- Fresh or frozen fish: Cod, sea bass, tuna, etc.
- Eggs: Whole eggs and egg whites.
- Healthy fats: Olive oil, avocado, and avocado oil.
- Low-sodium soups: Low-sodium canned or homemade soups.
- Dairy products: Milk, yogurt, unsalted butter, and low-sodium cheeses.
- Bread and baked goods: Whole-wheat bread, low-sodium tortillas, and unsalted crackers.
- Unsalted nuts and seeds: Pumpkin seeds, almonds, peanuts, etc.
- Low-sodium snack foods: Unsalted pretzels, unsalted popcorn, and unsalted tortilla chips.
- Low-sodium condiments: Vinegar, mayonnaise, low-sodium salad dressing, and low-sodium sauces.
- Low-sodium beverages: Tea, coffee, low-sodium vegetable juice, and water.
- Low-sodium seasonings: Garlic powder, no-salt blends, herbs, and spices.
Summary: Foods like fresh vegetables, fruits, most dairy products, eggs, and unsalted nuts are naturally low in sodium.
Potential risks of a low-sodium diet
Major health organizations, such as The Centers for Disease Control and Prevention, recommend that adults consume no more than 2,300 mg of salt daily and higher-risk groups, such as African Americans and older adults, no more than 1,500 mg.
It’s clear that a reduced sodium diet may decrease blood pressure in those with elevated levels and that high-salt diets increase stomach cancer risk. Still, evidence of other benefits of reducing this important mineral is conflicting.
For example, though sodium restriction is commonly used to treat heart failure, some studies have shown that reducing sodium can harm patient health.
A study of 833 people with heart failure demonstrated that restricting sodium to less than 2,500 mg daily was associated with a significantly higher risk of death or hospitalization than a non-restricted sodium diet.
Other studies have shown similar results.
Moreover, research has noted that consuming too little sodium can negatively impact heart health.
A review of 23 studies found that high and low sodium intake was associated with a higher risk of all-cause mortality and heart disease events.
Low sodium intake has also been linked to several other adverse health effects.
Consuming too little salt may increase cholesterol and triglycerides, insulin resistance, and hyponatremia (too little sodium in the blood).
While avoiding high-sodium, unhealthy foods like fast food is always best for your health, most healthy people don’t have to restrict sodium when following a balanced diet rich in whole foods.
Summary: Restricting sodium too much may lead to elevated cholesterol levels, insulin resistance, and hyponatremia. Some studies have shown that low-sodium diets negatively impact people with heart failure.
Low-sodium diet tips
If you follow a low-sodium diet, seasoning foods and making meals palatable can be challenging.
However, there are many easy ways to make your food delicious while avoiding salt.
Here are some tips for food prep and cooking on a low-sodium diet:
- Use lemon juice as a salt substitute.
- Cook with fresh herbs rather than salt.
- Experiment with new spices.
- Use citrus juices and olive oil as a bright, zesty salad dressing.
- Snack on unsalted nuts sprinkled with a mix of herbs.
- Make homemade soup flavored with garlic and ginger.
- Use more fresh produce in your meals and snacks.
- Prepare homemade hummus using dried chickpeas and flavor it with garlic and herbs.
- Make a low-sodium marinade with olive oil, garlic, vinegar, honey, and ginger.
Make more meals at home
According to research, foods eaten outside the home are the leading contributor to sodium intake.
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A study of 450 adults from different geographic areas found that commercial and restaurant foods eaten outside the home accounted for 70.9% of total sodium intake.
One of the best ways to reduce the amount of sodium in your diet is to control what goes into your food by cooking at home.
Eating more meals at home will reduce your sodium intake and help you lose weight.
A study of more than 11,000 adults found that those who cooked meals at home more frequently had lower body fat and better overall diet quality than people who ate fewer meals at home.
Summary: Using fresh herbs, spices, and citrus to flavor food and cooking more meals at home are helpful tips for following a low-sodium diet.
Low-sodium diets may improve high blood pressure, chronic kidney disease, and overall diet quality. They may also decrease stomach cancer risk.
Yet, too little sodium may have negative health effects, and this diet is unnecessary for most people.
If you follow a low-sodium diet, choose fresh and avoid salty foods. Cooking more meals at home is another great way to control your salt intake, allowing you to stay within your physician’s recommendation.