The 2026 Levels Guide to salt, sodium, and metabolic health
Despite what you’ve heard, not everyone needs to reduce their sodium intake, nor do most people need to guzzle salty drinks. Here’s what the science says about salt.
For decades, we’ve been told that eating too much salt (a.k.a. sodium chloride) will lead to high blood pressure and, in turn, cardiovascular disease. But recently, some have argued that there’s no need to restrict your intake or that you may even need more salt than current guidelines suggest. So which is it?
Beyond making food tasty, salt is essential for muscle contractions, transmitting nerve impulses, and helping maintain the right level of fluid within our cells and blood vessels. And, it turns out, both too much and too little salt negatively impact cardiovascular health, metabolism, insulin sensitivity, and more.
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Currently, the average American adult consumes more than 3,200 milligrams (mg) of sodium daily—well above the 2,300-mg cap recommended in the Dietary Guidelines for Americans (DGAs) or the even stricter 2,000-mg limit recommended by the World Health Organization (WHO). However, some medical experts think this higher intake could be a sodium “sweet spot” or that your needs might be even higher, especially if you follow a low-carb diet.
Use this guide to understand better why both high and low levels of salt intake may be problematic, what groups of people tend to be more “salt sensitive” than others, what increases your body’s demand for salt, and how to gauge your ideal intake.
What is the role of sodium in our bodies?
While salt is 40 percent sodium and 60 percent chloride, the sodium component worries many health experts due to its impact on blood pressure. But before we dive into the risks of too much (or too little) sodium, it’s essential to have a basic understanding of its vital roles in the body.
Sodium, along with other electrolytes, maintains the right balance of fluids in different compartments of the body (e.g., in cells, between cells, and in the bloodstream) by creating osmotic concentration gradients. These are when the concentration of solutes is higher on one side of a semi-permeable membrane than another, which helps shift molecules where they’re needed most.
Sodium, specifically, is the primary regulator of extracellular fluid volume (fluid outside of the cells), which includes blood volume (the liquid part of blood); therefore, it’s an important regulator of blood pressure. In fact, mechanisms in the body that help control blood pressure—like the renin-angiotensin-aldosterone system (RAAS)—do so partly by regulating the kidneys’ reabsorption and excretion of sodium and water.
Sodium and other electrolytes like potassium also affect nerve transmission and muscle contraction. This is vital not only for powering your way through a bout of exercise without getting cramps but also for things like maintaining a normal heartbeat and brain function. Here’s how it works: When ion pumps located in cell membranes use ATP (energy) to pump three sodium ions out of the cell in exchange for two potassium ions, it creates an electrochemical gradient (or charge difference) across the membrane that allows for the generation of nerve impulse conduction.
Lastly, within the small intestine, sodium assists in the absorption of chloride, amino acids, glucose, and specific B vitamins, as this electrolyte mineral is required for certain nutrient transporters (dubbed sodium-dependent transporters) to function properly.
Interestingly, eating more potassium-rich foods can help counter the potentially negative impact of high salt intake on blood pressure by relaxing blood vessel walls and increasing the amount of sodium excreted via urine. On the other hand, low potassium intake increases sodium reabsorption in the kidneys, which may exacerbate the effects of a high-salt diet.
Why too much salt can be bad for metabolic health
The biggest argument against eating lots of salt is that it elevates blood pressure and promotes downstream cardiovascular risks. As mentioned, the kidneys can help regulate the amount of sodium in the body—when sodium levels are low, the kidneys help reabsorb and retain sodium; when sodium levels are high, the kidneys release some sodium via the urine. But, if sodium intake is consistently very high (or the kidneys can’t remove enough of it for some other reason, like chronic kidney disease), then sodium can build up in the bloodstream.
Sodium attracts water. So, as blood sodium concentration rises, the body retains water and pulls it into blood vessels to dilute sodium to a safe range, which increases blood volume (i.e., the amount of blood flowing through your vessels). With increased blood volume, blood pressure naturally increases, and your heart has to work a bit harder to pump that additional blood throughout the body. Prolonged hypertension (blood pressure over 130/80 mmHg) can overstretch blood vessel walls in various organs and tissues, promoting inflammation and plaque buildup. This buildup impairs blood flow, setting the stage for cardiovascular events such as heart attack and stroke and increasing the risk of kidney disease. Animal studies also suggest that excess sodium can increase oxidative stress in the kidneys, further increasing sodium reabsorption and contributing to elevated blood pressure.
However, while some research suggests that reducing sodium intake is associated with lowering blood pressure in some people, and we know that high blood pressure is associated with cardiovascular disease, evidence linking low-sodium diets to decreased risk of cardiovascular disease and other outcomes is inconclusive. That said, findings from several well-known, short-term trials and follow-up studies over the years have made a case for being mindful of your salt intake for the sake of cardiovascular health—which is how experts established the current dietary sodium recommendations. Below are a few to consider.
(Just keep in mind, more recent research suggests that the relationship between salt, blood pressure, and heart health is less clear cut than these studies imply—we’ll get to that later!)
1. TOHP
In the Trials of Hypertension Prevention (TOHP I and TOHP II) conducted in the 1980s and ’90s, researchers studied the impact of various interventions on more than 3,000 pre-hypertensive adults. Reducing sodium intake by about 1,000 mg daily from baseline intake for 18 to 36 months was associated with a slight drop in blood pressure at 36 months (1.7/0.9 mmHg in TOHP I and 1.2/0.7 mmHg in TOHP II). A 2007 follow-up study found that participants from the sodium-restricted groups were 25 percent less likely to have a heart attack or stroke, require a procedure to clear clogged arteries or die of a cardiovascular-related cause in the following years.
Follow-ups in 2014 and 2016 also found a direct linear relationship between average daily sodium intake during the trial (as measured by the average of several 24-hour urinary sodium excretion tests, considered the gold standard) and subsequent cardiovascular disease risk. People who consumed the least sodium—between 1,500 and 2,300 mg per day—had the lowest cardiovascular risk.
While all of this gives the impression that the lower the salt intake, the better, there are important considerations: For one, it’s unclear what participants were eating in the years after the intervention, and some of the reduced cardiovascular risk could have been related to other dietary factors, such as increased intake of fruits and vegetables or decreased saturated fat intake.
2. DASH
The Dietary Approaches to Stop Hypertension (DASH) trials started in the ’90s were a driving force behind current sodium recommendations in the Dietary Guidelines for Americans. In the first study, published in 1997, participants with elevated blood pressure consumed either a standard American control diet, a similar diet with added fruits and vegetables, or a DASH diet rich in fruits, vegetables, and low-fat dairy and with reduced saturated and total fat. All the diets contained the same amount of sodium (about 3,000 mg daily). Results showed that both intervention diets improved blood pressure after eight weeks, with the DASH diet being the most effective, suggesting that adopting a healthy, minimally processed diet improves blood pressure.
A follow-up study demonstrated that reducing sodium intake amplified this effect: Reducing sodium to 1,500 mg per day while on the DASH diet had the most significant impact on blood pressure, lowering systolic blood pressure (the top number) by an average of 7 mmHg in participants without hypertension and 11.5 mmHg in participants with hypertension.
3. New England Journal of Medicine study
In a 2021 research review pooling data from more than 10,000 generally healthy people enrolled in six observational studies, researchers found that for every 1,000-mg increase in sodium intake (as measured via 24-hour urinary sodium excretion), there was an 18 percent increased risk of developing cardiovascular disease over an average follow-up period of about nine years. On the other hand, for every 1,000-mg increase in potassium intake, there was an 18 percent reduced risk.
In other words, the higher the sodium-to-potassium ratio of someone’s diet, the greater the cardiovascular risk, but if your diet is sufficiently high in potassium-rich foods such as vegetables, fruits, and legumes, you may be able to significantly buffer the blood pressure-elevating effects of sodium.
What to make of all of this
Based on the evidence, sodium influences blood pressure. But it’s challenging to quantify sodium’s exact impact since it doesn’t act in isolation—increasing intake of potassium and nutrient-rich whole foods, along with habits like exercise, amplifies cardiovascular benefits and can mitigate sodium’s blood pressure-raising effects. If your other habits are dialed in, you may not need to worry as much about your salt intake. Additionally, not everyone is equally “salt sensitive.” So increasing or decreasing your salt intake could have a larger or smaller impact on blood pressure, depending on factors like your baseline blood pressure, race, sex, age, and genetics. Research suggests that about one-third of otherwise healthy people (and more than 50 percent of people with hypertension) have an exaggerated blood pressure response to dietary sodium intake—meaning they are particularly salt-sensitive.
Case in point: An extensive 2020 Cochrane review of 195 randomized controlled trials (RCTs) and 27 population studies in which mean sodium intake was reduced from 4,700 mg to 1,500 mg per day, there was less than a 1 percent reduction in blood pressure among white people with normal baseline blood pressure. On the other hand, white people with hypertension experienced a blood pressure reduction of about 3 percent (or 5.7/2.9 mmHg). This finding suggests that reducing salt intake could be a beneficial component of treatment if you already have high blood pressure, but it may not have much effect if your blood pressure is normal. For Black and Asian people included in the review, the impact of sodium reduction on blood pressure was “a little larger,” suggesting these groups may be more salt sensitive, but more studies are needed to confirm.
Research suggests that women of all ages and people over 65 may also be more salt-sensitive, which may be related to hormonal differences and declining kidney function.
Additional metabolic health concerns
Beyond blood pressure, preliminary research suggests that long-term high salt intake may also promote metabolic problems due to the factors below. However, more research is needed to confirm these relationships and the level of sodium intake that may trigger them in humans.
- In animal studies, high salt intake (as well as dehydration) activates the polyol pathway, which prompts the body to convert more circulating glucose into fructose. Over time, excess fructose can promote downstream metabolic issues such as fatty liver.
- A high-salt diet (7,000 mg sodium per day) has been shown to promote overproduction of the hunger hormone ghrelin in humans compared to a low-salt diet (1,200 mg sodium per day), and animal studies suggest high-salt diets promote resistance to the satiety hormone leptin due to fructose overproduction. Together, these may encourage overeating.
- Small intervention studies suggest high salt intake (7,000 mg sodium per day) may reduce circulating levels of the hormones adiponectin, which regulates inflammation and insulin sensitivity, and GLP-1, which aids in glucose metabolism and promotes satiety.
- In several studies on laboratory mice and rats, a high-salt diet alters the composition of gut bacteria, but the effects were different, increasing levels of beneficial, bacteria-derived short-chain fatty acids in the rat study but decreasing them in the mouse study. However, in wildling mice, which have a gut microbiome that more closely mimics that of humans, high-salt diets trigger only minor shifts in gut microbial composition.
- Salt’s impact on insulin sensitivity isn’t fully understood. Some studies suggest that high salt intake promotes insulin resistance and that reducing salt intake can improve insulin sensitivity, but other research suggests that low salt intake promotes insulin resistance.
Why too little salt is bad for metabolic health
Although research suggests that reducing sodium intake may benefit certain salt-sensitive people, especially those with hypertension, it doesn’t necessarily indicate that very low sodium intake is always better. In fact, some emerging research suggests an overall J-shaped curve when it comes to sodium’s negative health consequences, with both very low and very high levels being the most problematic, while moderate levels carry lower risk.
In a 2014 review of 25 studies with a population-representative sample of participants (i.e., a mix of healthy people and those with disease), researchers found that people with sodium intake in the range of 2,645 mg to 4,945 mg per day—closer to the U.S. and global average intake—had the lowest risk of death from any cause compared to people who consumed lower or higher levels, demonstrating this U-shaped curve. A review from 2016 featuring a nearly 50/50 split of people with normal and high blood pressure made similar findings, with the lowest risk between 3,000 mg and 5,000 mg.
(These studies contrast the TOHP trials, which found a direct linear relationship between sodium intake and cardiovascular disease risk. Why the difference? Likely several factors, including the fact that the TOHP trials only included people with baseline high blood pressure—so, in theory, they would benefit more from the reduction—as well as the methodologies: the TOHP studies had far fewer people and were random control trials, while the review included many more people, but from observational studies.)
Similarly, an international study from 2018 found that higher sodium intake was associated with increased risk of cardiovascular disease and stroke, but only at levels over 5,000 mg sodium per day, supporting the theory that we may have more wiggle room than once thought. For this study, rates of stroke, death, and cardiovascular-related death also decreased as potassium intake increased, further demonstrating that potassium buffers the impact of a high-salt diet.
For white people without hypertension, in particular, the benefit of reducing sodium may not outweigh the risks. In the previously mentioned 2020 Cochrane review, people with normal baseline blood pressure who reduced sodium intake from 4,700 mg to 1,500 mg per day had, on average, minimal reductions in blood pressure (less than 1 percent) while simultaneously experiencing a 3-percent increase in cholesterol and a 6-percent increase in triglycerides, along with an increase in stress hormones like epinephrine. Other research suggests that significant changes in blood lipids and stress hormones are more likely when sodium intake dips below 2,000 mg daily.
Sodium reduction may also increase heart rate in both hypertensive and non-hypertensive people—up to 2.4 percent, according to a 2016 meta-analysis of 63 RCTs. The exact implications of a 2.4-percent increase are uncertain, but, in general, increased resting heart rate is associated with an increased risk of heart failure and mortality. For people with normal blood pressure, specifically, sodium reduction can increase heart rate without a corresponding decrease in blood pressure. This, coupled with the potential for increased blood lipids and stress hormones following significant sodium reduction, calls into question the benefit of population-wide recommendations to lower sodium intake to less than 2,000 or 2,300 mg per day, the study authors say.
As mentioned above, research suggests that both low and high sodium intake are associated with insulin resistance, reinforcing the idea of a U-shaped risk curve. One potential mechanism: Low sodium decreases the body’s water content and blood volume, which triggers an increase in compensatory hormones like epinephrine, renin, and angiotensin to keep body water and blood pressure in a safe range—but these hormones also inhibit the action of insulin. A 2014 study on healthy people also found that very low sodium intake (460 mg per day for about a week) impaired insulin secretion, which could make it harder to control blood glucose even if insulin sensitivity remains unchanged.
Keep in mind, current estimates suggest that, on average, American men consume around 4,274 mg of sodium per day, and American women consume around 3,142 mg of sodium per day—and these numbers are higher for those who rely more on processed, packaged foods. So, most people don’t need to worry about not getting enough salt. The message, instead, is that low-salt diets may not be as obviously healthy for the general population as once thought if studies demonstrating this U-shaped relationship are accurate.
There is some debate, however, over whether a U- or J-shaped risk curve for sodium intake truly exists, with some experts claiming that the pattern of elevated cardiovascular risk at low sodium intake is more likely to emerge when less accurate methods of assessing sodium intake are used, such as spot urine testing or a single 24-hour urinary sodium excretion test (as opposed to the average of multiple 24-hour tests). Experts agree that more high-quality research is needed to settle this argument.
How much salt do you really need?
Let’s start with the official recommendations: The DGA recommends no more than 2,300 mg per day, the WHO recommends no more than 2,000 mg per day, and the American Heart Association (AHA) recommends an “ideal limit” of 1,500 mg per day for most adults.
However, the “ideal” amount of dietary sodium for most people is debatable. Based on existing research, limiting sodium to this extent may benefit people with high blood pressure, but the benefit is inconsistent for people with normal blood pressure. Some experts say that to determine if current recommendations are just right or too low, we must establish whether there truly is a U-shaped curve relationship between sodium intake and increased health risk and the specific low and high values at which risk increases the most.
Until then, if you’re generally healthy, avoiding both extremes might make the most sense: Don’t load up on sodium unnecessarily, but don’t go out of your way to avoid salt, either. Per the authors of the 2020 Cochrane review, there’s no compelling evidence to date to recommend reducing sodium below 2,300 mg daily for the general population. It’s possible that a sodium intake closer to our current typical intake (somewhere between 2,300 and 4,600 mg per day, per the authors) may be optimal for this group.
If you’re eating a diet predominantly composed of whole and minimally processed foods (think vegetables, fruits, nuts, seeds, legumes, meat, eggs, fish, and whole grains) and salting your food to taste, you will likely fall somewhere in this moderate sodium range. Also, remember: Sodium has less of an impact on blood pressure and cardiovascular risk if you consume an overall minimally processed, nutrient-dense diet with plenty of potassium-rich food sources (e.g., leafy greens, legumes, mushrooms, avocado, tomatoes, squash, potatoes with skin, plain yogurt, and kefir), as demonstrated by the DASH diet trials and the 2021 research review cited previously.
According to researcher Andrew Mente, PhD, whose studies on sodium and cardiovascular disease suggest that daily intake of 3,000 and 5,000 mg may be safe for most populations, rather than simply focusing on sodium, “it’s best that we focus on improving the overall quality of the diet by eating more foods that are higher in potassium.”
On the other hand, if you have high blood pressure, cardiovascular disease, chronic kidney disease, or another condition that requires tight regulation of fluid balance; or if you take a medication that influences fluid balance (such as a diuretic), consult with your doctor about the safest dietary sodium range for you.
What are the scenarios in which someone might need more sodium?
Most of us probably get plenty of sodium. However, there are two main scenarios in which generally healthy people may need to be more mindful of their intake: 1) when transitioning to a very low-carb or ketogenic diet, or 2) after an activity that causes you to sweat a lot.
Low-carb diets
Low-carb diets promote water and sodium excretion via urine due, in part, to a reduction in insulin levels. Insulin has sodium-retaining effects through its actions on the kidneys, so when insulin levels naturally drop following reduced carbohydrate intake, sodium and water drop along with it. “Individuals on low-carb/keto diets experience a significant reduction in sodium that occurs most dramatically during the first two weeks,” says Levels advisor Dominic D’Agostino, PhD. “Based on the literature to date, we can confidently say that someone on [these diets] will benefit from increasing their sodium intake, and overall electrolyte intake, beyond the recommended 2,300 milligrams.”
Failure to get enough sodium and other electrolytes—particularly when initiating a low-carb diet—can result in side effects associated with the “keto flu,” such as fatigue, headaches, orthostatic hypotension (low blood pressure and dizziness upon standing), and muscle cramps. “I personally experience this if I’m not getting 4,000 to 5,000 milligrams of sodium, balanced with other electrolytes,” D’Agostino says. This effect lessens but doesn’t disappear over time and with adaptation of the body’s RAAS, which helps regulate blood pressure and fluid and electrolyte balance.
Sweating
Endurance exercise is associated with sodium loss through sweat, and replacing both fluids and electrolytes can be essential for rehydration. For workouts lasting less than 60 to 90 minutes, water alone is typically adequate for replacing fluids. But for longer workouts, or if you’re exercising in the heat and sweating a lot, replacing sodium and other electrolytes may also be necessary. “Maintaining sodium and electrolyte intake to counteract this sustained loss is particularly important for athletes, military personnel, and first responders subjected to high workloads and heat stress,” D’Agosinto adds.
In either case, D’Agostino says restoring electrolytes can be as simple as liberally salting food and eating a nutrient-rich diet that contains other key electrolytes (like magnesium and potassium) or consuming a sugar-free electrolyte supplement such as LMNT. Replacing electrolytes that have been lost, along with water, is key for optimal hydration and normal blood pressure, given the role of salt and other electrolytes in maintaining the right balance of fluid inside cells and the bloodstream (by regulating osmotic fluid shifts between these compartments). A good general rule: If you’re feeling good (no fatigue, headaches, dizziness, or muscle cramps), your intake may be sufficient. Consider how you feel and your recent activity and eating habits when deciding whether or not to take a supplement.
What would change our mind?
The takeaway is that outside of a few populations—low-carb dieters, people with hypertension—most of us probably don’t need to worry much about our salt intake. What evidence might lead to a different take?
According to experts, including Mente and others, changing the current recommendations to liberalize sodium intake (or to caution against the potential risks of low intake) requires better studies with more long-term data.
Ideally, these studies would be larger, long-term RCTs that compare low levels of sodium intake to more moderate levels and evaluate their impact on cardiovascular disease risk and other health outcomes among a representative sample of the population. Most previous trials, like the DASH diet trials, have been short-term since it’s very difficult to control people’s dietary sodium intake over time. Additionally, these trials have frequently been conducted on people who already have baseline elevated blood pressure—not the general population.
However, while there’s a growing consensus that long-term RCTs are necessary and would lead to better guidance for a healthy population, they would be extremely difficult to perform since maintaining a consistent sodium level in the diet would be impractical, especially for the low-intake groups. And while this could be addressed by providing participants with all their meals, that wouldn’t likely be financially feasible. Per some researchers, conducting these trials in prison settings may offer the best way to control sodium intake for a prolonged period, but this may present ethical issues.
In the meantime, there may be more practical ways to upgrade the quality of research in ways that might move our guidance. Some experts have recommended long-term observational studies on a large, representative sample of the population comparing various levels of sodium intake to health outcomes. Specifically, these observational studies should estimate participants’ sodium intake using multiple 24-hour urinary sodium excretion measurements—the gold standard for gauging sodium intake. Many existing observational studies have used less reliable sodium intake estimation methods such as food diaries, 24-hour dietary recalls, and food frequency questionnaires, or they have been performed on people who already have baseline elevated blood pressure.
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