Sodium — What It Means in Your Blood Test
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Sodium helps control the water balance in your body and supports your blood pressure, nerves, and muscles.
A Sodium result tells you whether this salt sits in the right range. It quietly governs how water is shared through your body and helps steady pressure, nerves, and muscle action.
Also known as: serum sodium, Na, serum Na, plasma sodium, Na+
This isn't a case where higher or lower is better. Your body keeps it in a narrow band, and both directions can matter.
Last reviewed: 2026-08-16
What is Sodium?
Sodium is the main salt in your blood and body fluids. It controls your water balance, helps set your blood pressure, and keeps your nerves and muscles working. This test measures your level.
Why is Sodium tested?
Part of routine panels, this test helps check your hydration and kidneys, and can explain symptoms like confusion or swelling.
What is a normal Sodium range?
- India
- No India-specific national reference interval is published for this parameter; your lab's printed range is the most reliable comparison.
- Global
- Normal: 136–145 mEq/L (CLSI / clinical reference)
Ranges vary by lab, method and equipment — the range printed on your own report is the one that applies to your result.
Source: [CLSI, 2010]
What does your Sodium value mean?
There is no widely-accepted set of value bands for this parameter. Compare your result with the reference range printed on your own report, and discuss it with your doctor.
What does a high Sodium result mean?
A high level usually means you have lost more water than salt, often from dehydration. It can cause thirst and confusion worth discussing with your doctor.
What does a low Sodium result mean?
A low level can come from holding too much water, some hormone imbalances, or drinking too much fluid. It can cause nausea, headache, or confusion worth discussing with your doctor.
What can affect your Sodium result?
- Fluid and water intake
- Kidney and hormone control
- Salt intake
- Vomiting, diarrhoea, or sweating
- Water pills
Questions to ask your doctor
About this result
- What does my Sodium result mean for me specifically, given my age and health?
- Is my Sodium in the range that is right for me, not just the lab's general range?
What to do next
- Could anything I eat, do, or take have affected my fluid balance salt result?
- Is there anything I should do about my Sodium, or is it fine to leave as it is?
About retesting
- Does my Sodium need to be repeated, and if so, when?
- The typical range for Sodium can vary between labs — should I compare my result against my own lab's printed range?
The bigger picture
- Should my Sodium be looked at together with my Potassium and Chloride result?
- Does my Sodium connect to any condition I already have, or to anything I have noticed in how I feel?
Frequently asked questions
- What is Sodium?
- Sodium is the main salt in your blood and body fluids. It controls your water balance, helps set your blood pressure, and keeps your nerves and muscles working. This test measures your level. Part of routine panels, this test helps check your hydration and kidneys, and can explain symptoms like confusion or swelling.
- What is a normal fluid balance salt range?
- A typical adult range is around Normal: 136–145 mEq/L (CLSI / clinical reference). No India-specific national reference interval is published for this parameter; your lab's printed range is the most reliable comparison. Ranges vary by lab, method and equipment — the range printed on your own report is the one that applies to your result.
- What does a high Sodium result mean?
- A high level usually means you have lost more water than salt, often from dehydration. It can cause thirst and confusion worth discussing with your doctor.
- What does a low Sodium result mean?
- A low level can come from holding too much water, some hormone imbalances, or drinking too much fluid. It can cause nausea, headache, or confusion worth discussing with your doctor.
- What can affect your Sodium result?
- Several everyday factors can influence it, including Fluid and water intake, Kidney and hormone control, Salt intake, Vomiting, diarrhoea, or sweating, Water pills.
Sources
- CLSI (2010) — CLSI EP28-A3c: Defining, Establishing, and Verifying Reference Intervals in the Clinical Laboratory
Part of the Electrolytes
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