Eating more salt and protein is the most common dietary recommendation when sodium levels are mildly low, a condition doctors call hyponatremia. But what you eat is only half the equation. In many cases, the problem is less about not getting enough sodium and more about having too much water in the body relative to the sodium that is there. That distinction matters because it changes whether the fix is adding salt to your meals, cutting back on fluids, eating more protein, or some combination of all three.
Why Low Sodium Is Usually a Water Problem, Not Just a Salt Problem
Before reaching for the saltshaker, it helps to understand what is actually going on. Low sodium in the blood does not always mean you are not eating enough salt. The condition reflects an imbalance between total body water and total body solutes, meaning the water in your body has diluted the sodium to below normal levels.1NCBI Bookshelf. Hyponatremia That imbalance can happen because you drank too much water, because your kidneys are holding onto water they should be excreting, because of a medication side effect, or because of an underlying health condition affecting the heart, liver, or kidneys.
This is why your doctor’s advice will depend on the cause. Someone whose sodium dropped because they were drinking huge amounts of water during a marathon needs a very different plan than someone whose sodium is low because of a medication or a chronic illness. The dietary strategies below apply mainly to mild, chronic, or diet-related causes of low sodium. Severe drops with symptoms like seizures, vomiting, or extreme drowsiness are a medical emergency and require intravenous treatment, not a change in what you eat.2PubMed Central. Hypertonic Saline for Hyponatremia: Meeting Goals and Avoiding Harm
Adding Salt and Potassium to Your Diet
For mild hyponatremia, the most straightforward dietary step is increasing your intake of sodium and potassium through food and, when recommended by a doctor, oral supplements. Conservative treatment with oral sodium and potassium replacement is a standard approach for mild cases.3PubMed Central. Salt and water: a simple approach to hyponatremia In practical terms, that means you do not need to fear salty food the way most dietary guidelines tell you to. For someone with confirmed low sodium, adding salt to meals, choosing broth-based soups, eating pickles, olives, cheese, cured meats, and other naturally salty foods can all help nudge levels upward.
Some foods that are naturally higher in sodium include:
- Broth and bouillon: A cup of chicken or beef broth can deliver 800 mg or more of sodium, and it is easy to sip throughout the day.
- Cheese: Hard cheeses like parmesan and feta tend to be particularly salty.
- Pickled vegetables: Pickles, sauerkraut, and kimchi are all sodium-rich.
- Cured or smoked meats: Deli meats, bacon, and smoked fish carry significant sodium.
- Soy sauce and condiments: Even small amounts of soy sauce or fish sauce add substantial sodium to a meal.
Potassium matters here too, even though it gets less attention. Potassium and sodium work together to regulate fluid balance, and oral potassium replacement is often part of the treatment plan alongside sodium. Good dietary sources of potassium include bananas, potatoes, avocados, spinach, and beans. If your doctor has flagged both low sodium and low potassium, focusing on foods that deliver both nutrients together, like salted nuts or a baked potato with cheese, can be efficient.
Why Protein Intake Makes a Difference
One of the more overlooked dietary strategies for low sodium involves eating more protein. This surprises people because protein does not contain much sodium itself. The connection is indirect but meaningful. When your body breaks down protein, it produces urea, which is a solute the kidneys use to help excrete excess free water. If you are not eating enough protein, your body generates less urea, and your kidneys have a harder time getting rid of the extra water that is diluting your sodium.4PubMed Central. Current Challenges in the Evaluation and Management of Hyponatremia – Section: Low Solute Intake Is an Underrecognized Cause of Hyponentremia
This is a particularly common issue in people who eat very little, those on extremely restrictive diets, heavy beer drinkers (sometimes called “beer potomania”), or older adults with poor appetites. In these groups, simply increasing dietary protein and salt has been shown to help improve water excretion and move sodium levels back toward normal.5PubMed Central. Salt and water: a simple approach to hyponatremia – Section: The case revisited Practical protein sources include eggs, chicken, fish, Greek yogurt, cottage cheese, tofu, and legumes. Even a modest increase in protein can raise your body’s daily solute load enough to make a measurable difference in how well your kidneys clear extra water.
If you have been told your low sodium is related to low solute intake, the fix is less about adding a pinch of salt to your pasta and more about making sure your overall diet contains enough calories, protein, and electrolytes to give your kidneys the raw materials they need to maintain balance.
Cutting Back on Fluids
Because hyponatremia is fundamentally about too much water relative to sodium, restricting how much you drink is often just as important as changing what you eat. This is counterintuitive in a culture that encourages constant hydration. But for someone with low sodium, drinking less water, not more, is frequently part of the treatment. Fluid restriction is a cornerstone management strategy, particularly in cases linked to conditions where the body is holding onto water inappropriately.6Taylor & Francis Online. ‘Dos and don’ts’ in the management of hyponatremia – Section: RECOMMENDATIONS
How much fluid restriction depends on how low your sodium is and what is causing it. In mild cases, a doctor might suggest limiting yourself to around 1 to 1.5 liters of total fluid per day, which includes water, coffee, tea, soup, and anything else that is liquid at room temperature. That is less than many people drink without thinking about it, especially if they are used to carrying a water bottle everywhere. The point is not to get dehydrated. The point is to stop the excess water from further diluting the sodium you have.
For people used to drinking large volumes of water, whether out of habit or because they believe more water is always healthier, this adjustment can feel uncomfortable at first. But low sodium itself causes far more unpleasant symptoms, including nausea, headaches, confusion, and fatigue. Pairing fluid restriction with an increase in dietary salt and protein attacks the problem from both directions: less water coming in and more sodium and solutes to help your kidneys move the excess water out.
Exercise-Related Low Sodium and Overhydration
One specific scenario where diet and fluid habits become especially relevant is during prolonged exercise. Exercise-associated hyponatremia occurs when someone’s blood sodium drops below normal during or up to 24 hours after extended physical activity. It has been documented in nearly every form of endurance sport, from marathons and triathlons to long hikes and cycling events. The common thread is excessive water intake during the activity, often combined with elevated levels of a hormone that tells the kidneys to retain water.7PubMed Central. Exercise-Associated Hyponatremia
For years, athletes were told to drink as much as possible to avoid dehydration. That advice turned out to be dangerous for some people. Drinking plain water beyond what thirst demands during a long race can dilute blood sodium to dangerous levels, especially if you are a slower runner (spending more hours on the course and more hours drinking), if you have a smaller body, or if you sweat less than average. The practical fix is to drink to thirst rather than on a schedule, and to include electrolyte-containing drinks rather than plain water during prolonged exercise. Salty snacks during an ultramarathon or a long training day, things like pretzels, salted crackers, or electrolyte tablets, serve a real physiological purpose.
If you have had an episode of exercise-associated hyponatremia before, your dietary strategy around training sessions should include pre-loading with a salty meal, carrying sodium-containing foods or drinks during the activity, and deliberately avoiding overdrinking. This is one of the few situations where eating salty food before and during exercise is genuinely protective rather than just a comfort preference.
Foods and Habits That Can Make Low Sodium Worse
If your sodium is already low, certain eating and drinking patterns can push it lower. Being aware of these helps you avoid accidentally undoing the benefits of adding salt and protein.
- Excessive plain water: Drinking large volumes of water, especially without food, dilutes whatever sodium is in your blood. This is the single most common dietary contributor to worsening hyponatremia.
- Very low-calorie or low-protein diets: Crash diets, prolonged juice cleanses, and extremely restrictive eating patterns reduce the solute load your kidneys need to excrete free water effectively.
- Heavy beer drinking: Beer has a lot of water and very little solute. Drinking large quantities without eating much food is a classic setup for low sodium, sometimes called beer potomania.
- Tea-and-toast diets: Common among older adults living alone, a diet consisting mostly of tea and toast delivers a lot of fluid with minimal protein, sodium, or other electrolytes. Over time, this pattern can drive sodium levels down.
The theme across all of these is the same: too much water coming in with too few solutes to balance it. Your kidneys are remarkably good at managing sodium, but they need raw materials to work with. A diet that is very low in protein, salt, and calories gives them almost nothing to work with, and the extra water just accumulates.
When Dietary Changes Are Not Enough
Adjusting what you eat and drink works well for mild, chronic, or diet-related hyponatremia. It does not work when sodium levels have dropped severely or when the underlying cause is a serious medical condition. Severe symptoms of hyponatremia, including vomiting, respiratory distress, deep drowsiness, seizures, or coma, require emergency treatment with intravenous hypertonic saline in a hospital setting.2PubMed Central. Hypertonic Saline for Hyponatremia: Meeting Goals and Avoiding Harm No amount of broth or salted nuts will correct sodium fast enough in that situation.
Even in less dramatic cases, dietary changes alone may not be sufficient if the hyponatremia is caused by a medication (certain antidepressants, diuretics, and anti-seizure drugs are common culprits), by a condition like syndrome of inappropriate antidiuretic hormone secretion, or by heart or liver disease that causes the body to retain fluid. In these situations, treating the underlying cause or adjusting the medication matters far more than what you are eating. Dietary strategies in those cases serve as a complement to medical treatment, not a substitute for it.
If your sodium has been measured as low on a blood test, the most important step is working with your doctor to identify why it is low before deciding on a dietary approach. A person whose low sodium is driven by excessive water drinking will benefit hugely from reducing fluids and adding salt. A person whose low sodium is driven by heart failure needs a completely different management plan, one that might actually include sodium restriction in some contexts. The diet that helps depends entirely on the diagnosis behind the number.
Practical Meal Ideas for Mildly Low Sodium
If your doctor has confirmed that your low sodium is mild and that increasing salt and protein in your diet is appropriate, here are some practical ways to structure your meals. These are not medical prescriptions; they are everyday food choices that happen to deliver the nutrients your body needs to correct the imbalance.
Breakfast could be eggs scrambled with cheese and a side of smoked salmon or bacon. All three are good sources of sodium and protein, and the combination is far more helpful than a bowl of fruit with a large glass of water. A mid-morning snack of salted nuts or a handful of olives adds sodium without requiring much effort. Lunch might be a bowl of soup made with real broth (not low-sodium broth) alongside a sandwich with deli meat and cheese. Dinner could center on grilled chicken, fish, or tofu with a generous seasoning of salt, paired with potatoes or rice and a side of pickled or fermented vegetables.
The key shift for most people is giving themselves permission to eat salt. Decades of public health messaging about reducing sodium for heart health have made many people reflexively avoid it. That advice is directed at the general population, and especially at people with high blood pressure. If you have been diagnosed with low sodium, you are in the opposite situation, and the usual sodium-avoidance advice does not apply to you. Eating enough salt, enough protein, and limiting unnecessary fluid intake is the practical combination that addresses mild hyponatremia from the dietary side.
Older Adults and the “Tea and Toast” Pattern
Low sodium is disproportionately common in older adults, and the reason often comes down to diet more than people realize. Aging tends to reduce appetite, blunt thirst signals in confusing ways, and lead to simplified eating patterns. The stereotypical “tea and toast” diet that many older adults fall into, sometimes out of convenience, sometimes out of loneliness or depression, delivers a high ratio of water to solutes. Tea is almost entirely water. White toast has minimal protein and very little sodium. Add in a prescription diuretic and you have a recipe for slowly declining sodium levels over weeks or months.
For an older adult in this situation, the fix often starts with making meals more nutrient-dense rather than larger. Adding an egg to breakfast, switching from plain toast to toast with cheese or peanut butter, replacing some of the tea with a small cup of broth, and including a protein source at every meal can meaningfully change the solute load the kidneys have to work with. Family members and caregivers who notice an older relative eating very little, drinking a lot of tea, and seeming confused or unusually fatigued should consider suggesting a sodium check. The symptoms of mild chronic hyponatremia in older adults, including unsteadiness, difficulty concentrating, and increased fall risk, are easily mistaken for normal aging or early dementia, and the dietary fix is straightforward once the problem is identified.