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How sodium fits into POTS

When you stand up, gravity pulls blood down toward your legs and belly. Your body normally adjusts within seconds. In POTS, that adjustment does not go smoothly, and the heart speeds up to keep blood moving to the brain.^[4]

Many people with POTS also have less blood volume than expected. One review puts it at up to 70% of patients,^[4] and a 2025 study that measured blood volume directly found that the bigger the shortfall, the higher the standing heart rate.^[9]

Sodium helps your body hold on to the water you drink, which raises plasma volume. That is why clinical guidance pairs more salt with more fluid as one of the first, non-drug steps, usually alongside compression garments and a structured exercise plan.^{[1][2][3][5][7]}

What the research shows

The evidence is real but still small. In a 2021 crossover trial, 14 people with POTS spent six days on a low-sodium diet and six days on a high-sodium diet. On high sodium, their plasma and blood volume went up and their heart rate jumped less when they stood. It improved, but it did not fully match healthy volunteers.^[8]

Reviews of the wider literature land in the same place: more salt tends to help in the short term, reviewers suggest it particularly for people whose typical urine sodium is low, and long-term trials have not been done yet.^[10][11] Researchers have also pointed out that a lot of salt over many years has its own costs, which is why more is not automatically better.^[12][13]

How much do clinicians suggest?

These are starting points from published guidance. Your number is the one your doctor gives you.

Watch the unit. These figures are grams of salt, not grams of sodium. Salt is about 39% sodium by weight, so 10 g of salt is roughly 3,900 mg of sodium. The two get mixed up easily online, and the difference is more than double.

Tracking sodium: reading the label

Nutrition Facts labels list sodium in milligrams (mg), so milligrams are the easiest unit to track. The Daily Value printed on labels is set for the general public, and POTS guidance often sits well above it, which is another reason to get a specific target from your doctor.

A spoonful of salt can weigh different amounts depending on how fine or coarse the crystals are, so the milligrams on a label are more reliable than a measuring spoon.

Managing your intake through the day

• Pair salt with fluid. Published guidance always recommends the two together, at about 3 L of fluid a day.^[1][2]
• Food counts. High-salt foods, salting your meals, salt sachets, salt sticks and tablets are all listed as ways to reach a target.^[1]
• Expect some trial and error. In short-term studies, the side effects reported were nausea and intolerance to salt. Tell your doctor if it is a problem.^[12][11]
• Ask about a 24-hour urine sodium test. It turns a guess into a number and helps show whether more salt is likely to help you.^[10]
• Keep an eye on blood pressure. Reviewers recommend checking it, including lying down, while on a higher-salt plan.^[10][13]
• Write it down. A week or two of notes gives you and your doctor real numbers to work with.

Details like the best time of day, the best form of salt and how long to stay on a plan have not been well studied yet. A 2022 review noted there is still little agreement on dose, form or duration.^[10]

A simple daily tracker

Print the full three-page version below, or copy this into a notes app. Add up the sodium column from labels, and note how you felt.

Download my free guide

When to be careful

• Blood pressure, heart or kidney conditions. Reviewers suggest salt for people without heart and blood vessel conditions and with normal lying-down blood pressure, and caution that high sodium can strain the heart and kidneys over time. Check with your doctor first.^[10][12]
• Not every type of POTS is the same. POTS has several overlapping causes, and treatment is matched to the type. Ask what fits your situation.^[6]
• Children and teens. Studies in young people are small. Oral rehydration has shown short-term benefit, and urine sodium may help predict who responds, so their plan should come from their care team.^[14][15]
• Long-term use. Most studies last days to weeks. The long-term effects of a high-salt diet are still being studied.^[11][12][13]