Cutting salt from your diet may help you lose water weight. However, there's no recommended daily sodium intake to lose weight. That being said, preliminary evidence indicates that too much sodium in your diet may contribute to weight gain.
Though reducing your sodium intake offers many benefits, which may include helping you drop those unwanted pounds, you may have more success losing weight by focusing on calories. Consult with your primary care provider before attempting any weight-loss diet.
There's no daily recommended sodium intake specific for weight loss. However, the American Heart Association (AHA) says you should aim for no more than 2,300 milligrams of sodium a day for better health.
Sodium and Weight Loss
Sodium is an essential mineral your body needs to maintain fluid balance and normal nerve and muscle function. However, you only need about 500 milligrams of sodium a day to support these normal body functions, according to the Harvard T.H. Chan School of Public Health. Most Americans consume about 3,400 milligrams of sodium a day, notes the Academy of Nutrition and Dietetics.
Most of the sodium in your body is found in your extracellular fluid, or the fluid outside of your cells. The amount of sodium in your body affects total fluid volume. If your extracellular fluid has too much sodium, your total fluid volume increases, leading to fluid retention.
According to the U.S. National Library of Medicine, too much salt in your diet contributes to fluid retention, which may lead to water weight gain. When it comes to sodium and weight loss, reducing your sodium intake may prevent fluid retention and help you lose excess water weight.
Sodium and Weight Gain
Most experts agree that too much sodium may affect the numbers on your scale due to the role the mineral plays in maintaining fluid balance. However, preliminary evidence indicates that too much sodium in your diet may also contribute to weight gain and obesity.
Until recently, most researchers believed sodium regulation in your body was fairly straightforward, according to the National Institutes of Health. Eating too much salt or sodium triggers the thirst mechanisms in your brain, increasing your desire to drink more to help your kidneys excrete the excess sodium in your urine.
However, sodium balance in your body may be more complex than that, according to a May 2017 study published in the Journal of Clinical Investigation. During this small study (10 subjects), participants were given tightly controlled amounts of sodium, ranging from 6 grams to 12 grams a day, for 30 to 60 days. Researchers collected urine samples throughout the study period.
While the researchers found that sodium excretion increased when sodium intakes were high, they also found that the body conserved water and the participants drank less with higher sodium intakes. The alterations in sodium intake also coincided with fluctuations in the hormones that control fluid and sodium balance.
Further, the researchers noted that the body needed a lot of energy to excrete the excess sodium while conserving water, and this energy was provided by the breakdown of muscle tissue.
A March 2018 study published in the Proceedings of the National Academy of Sciences of the United States of America found that a high-salt diet increased production of fructose in the liver and triggered leptin resistance in mice. Leptin is a hormone that controls your appetite.
Higher levels of leptin decrease your desire to eat. However, with leptin resistance, your body doesn't respond to the appetite-controlling hormone, so you always feel hungry. It's believed that leptin resistance is a factor that contributes to weight gain and obesity.
Though these studies show there may be a connection between sodium and weight loss, the 2017 Journal of Clinical Investigation study included only 10 participants, and the 2018 National Academy of Sciences study was conducted on mice. Large clinical trials are needed to better understand the role sodium plays in weight control before final conclusions can be made.
Daily Sodium Intake
There aren't specific recommendations for daily sodium intake to lose weight. However, there are recommendations for daily sodium intake for general health and wellness. The AHA recommends that you consume no more than 2,300 milligrams of sodium a day, and ideally keep your daily intake closer to 1,500 milligrams a day.
In addition to helping you lose excess water weight, keeping your daily sodium intake low may reduce your risk of developing high blood pressure, which is a risk factor for heart disease and stroke. Your low-sodium diet is also good for your bones. High intakes of sodium increase the loss of calcium, which may be pulled from your bones, according to the Harvard T.H. Chan School of Public Health.
According to the AHA, 70 percent of sodium in the American diet comes from processed foods, not the salt shaker. Paying more attention to the amount of sodium you consume may lead to healthier food choices like fruits, vegetables, whole grains, beans and lean animal proteins such as poultry and fish. In addition to having less sodium, these foods may also be lower in calories and more filling, and they're often the foods of choice on most healthy, balanced weight-loss plans.
How You Lose Weight
Though the association between sodium and weight loss is uncertain, there's little doubt about the connection between calories and weight loss. To lose weight, you need to create a negative calorie balance, which forces your body to burn fat for energy.
One pound of fat contains 3,500 calories, according to the American Academy of Family Physicians (AAFP). Creating a daily 500-calorie negative balance can help you lose 1 pound a week. To swing your calorie equation toward weight loss, you need to eat fewer calories or burn more calories through exercise — or both.
Though you can lose weight by eating fewer calories, the AAFP says you may have more success losing weight and keeping it off using a combination of diet and exercise. The AAFP also recommends that you aim to lose no more than 2 pounds a week. Losing too much weight too quickly generally leads to muscle loss, which may leave you feeling too tired to work out, which may increase your risk of regaining the weight you lost.
Instead of worrying about daily sodium intake to lose weight, you need to know your daily calorie intake. The number of calories you need in order to drop those unwanted pounds depends on many factors, including your sex, body composition, activity level, age and overall health. Your health care provider can help you determine your daily calorie intake to help you lose weight.
According to the National Heart, Lung, and Blood Institute, many women can lose weight following a 1,200- to 1,500-calorie diet plan, while most men can lose following a 1,500- to 1,800-calorie plan. You should never follow a diet plan that restricts your calorie intake to less than 1,000 calories a day unless advised to do so by your health care provider.
- Harvard T.H. Chan School of Public Health: "Salt and Sodium"
- Academy of Nutrition and Dietetics: "Is Sodium the Same Thing as Salt?
- Advances in Nutrition: "Sodium"
- U.S. National Library of Medicine: "Edema"
- National Institutes of Health: "How the Body Regulates Salt Levels"
- Journal of Clinical Investigation: "High Salt Intake Reprioritizes Osmolyte and Energy Metabolism for Body Fluid Conservation"
- Proceedings of the National Academy of Sciences of the United States of America: "High Salt Intake Causes Leptin Resistance and Obesity in Mice by Stimulating Endogenous Fructose Production and Metabolism"
- Diabetes, Metabolic Syndrome and Obesity: Targets and Therapy: "Leptin Resistance: Underlying Mechanisms and Diagnosis"
- American Heart Association: "How Much Sodium Should I Eat Per Day?"
- American Academy of Family Physicians: "What It Takes to Lose Weight"
- National Heart, Lung, and Blood Institute: "Healthy Eating Plan"