Sodium, an essential nutrient, helps your body function by maintaining blood pressure and fluid levels, as well as supporting your muscles and nerves.
The body regulates sodium — or salt — levels by releasing excess sodium in urine as well as controlling the amount of water that’s released.
Short-term stress tends to increase the amount of sodium released in urine.
But research has also found that some people’s bodies retain sodium after exposure to stress, though they may still excrete it at night. This nighttime excretion may be more likely if a person experiences more frequent stress during the day.
Therefore, the effects of stress on sodium levels may vary from person to person. And there’s not yet enough evidence to determine cause and effect.
Some researchers have even found a reverse effect in rats, stating that high sodium levels can inhibit the body’s response to stress and boost anti-stress hormones.
Bodily processes like sodium storage and release aren’t the only impacts stress and anxiety can have.
You may experience headaches, muscle tension, and an upset stomach, along with changes to your heart rate and blood pressure.
Stress can also affect breathing, with some people experiencing asthma attacks or panic attacks.
While short-term stress usually results in short-term changes to your body, chronic stress can lead to long-term concerns with vital organs such as the heart.
Low sodium levels are rare in the U.S. due to the average diet —they’re more typically seen in older adults.
When the sodium level in the blood does fall below 135 milliequivalents per liter (mEq/L), hyponatremia occurs.
Typical symptoms include:
- confusion
- nausea and vomiting
- headaches
- fatigue
- muscle weakness or twitches
Eventually, a person may experience seizures and fall into a coma.
While the impact of stress on sodium is still under discussion, other medical and lifestyle factors are known to result in low sodium levels.
Severe vomiting or diarrhea
Anything that can cause dehydration, such as vomiting and diarrhea, can decrease sodium levels as salt is lost from the body.
And when you try to replace those fluids with water, the sodium that’s still present dilutes.
Drinking too much fluid
The opposite —having too much fluid inside your body —can also result in low sodium levels as the water dilutes the sodium in the blood. The kidneys may struggle to excrete the excess water.
This can happen if you’re intensely exercising (and replenishing with fluids) or if you have a condition such as polydipsia. But it’s rare.
Kidney, heart, and liver conditions
Certain kidney disorders, heart failure, and liver cirrhosis are also potential causes. They can make the body retain fluid, which tends to dilute the sodium in the blood.
Earlier signs of kidney disease may include:
- fatigue
- concentration and sleep issues
- poor appetite
- swollen feet and ankles
- dry skin
- needing to urinate more frequently
The following can be symptoms of heart failure:
- fatigue
- shortness of breath
- swelling of the legs, ankles, or stomach
- persistent coughing
Liver cirrhosis is a trickier one to identify as many symptoms aren’t obvious until the condition has worsened.
If you notice that your appetite and tiredness levels have changed or that you have lost weight, feel nauseous, or have swollen veins, consult with a doctor or other healthcare professional.
Diuretics and other medications
Diuretics increase the amount of sodium that’s removed from the body. If you’re more prone to low sodium levels, you may be more at risk of experiencing hyponatremia when taking diuretics.
Antidepressants and some pain medications can also impact kidney and hormonal functions that are needed to regulate sodium levels.
This list isn’t exhaustive. If you take over-the-counter or prescribed medication and are concerned about dehydration or heart palpitations, consult with your pharmacist, prescribing clinician, or other healthcare professional.
Hormonal conditions
Syndrome of inappropriate anti-diuretic hormone (SIADH) results in the production of high levels of anti-diuretic hormone, leading fluid to build up inside the body.
This is another condition that’s difficult to notice at first. But symptoms can include:
- nausea and vomiting
- restlessness
- personality changes
- loss of appetite
Weakness, cramps, and seizures can also occur.
Addison’s disease impacts the adrenal gland, which is needed to balance things like sodium. Symptoms can range from weakness, fatigue, and weight loss to fainting, mouth sores, and a darkening of the skin.
And an underactive thyroid can cause low sodium levels. Look out for weight gain and fatigue early on. Dry skin and hair, feeling cold, constipation, and muscle issues are also common.
It depends on what’s causing the low levels.
Treatment can be short-term, meaning just a few hours or days, or long-term if an underlying disease needs to be managed. And it can be simple or complex.
If hyponatremia is on the severe side, replacing sodium must be done
If sodium is lost through the likes of sweating, vomiting, or diarrhea, then replenishing it is a good idea through special rehydration drinks. These are often used by people who exercise a lot.
The best thing to do is to remain hydrated — enough that your urine is pale yellow. Remember to drink enough fluids when the weather is especially warm or if you’re not feeling well.
Of course, there’s always the chance that you’re consuming too much water. In rare cases, doctors may advise consuming less to avoid the dilution of sodium in the blood.
Rarer still is advice to gradually add more salt to your diet. This is only likely if you have been diagnosed with a condition like SIADH.
Avoid decreasing water intake or increasing salt intake until you consult with a healthcare professional.
Your clinician will advise specific treatment if necessary — it all depends on what’s causing your sodium levels to be low. For example, if medication is the culprit, your clinician may adjust your dosage or change your prescription entirely.
You may also need to go to the hospital for intravenous fluid to boost sodium levels.
If you’re more at risk of hyponatremia and start feeling nauseous and weak or start having headaches and muscular issues, seek medical attention as soon as possible.
Confusion, seizures, and a loss of consciousness all require immediate emergency care.
You know yourself best. And while low sodium levels are relatively rare, if something doesn’t feel right, contact a healthcare professional for advice.
Lauren Sharkey is a U.K.-based journalist and author specializing in women’s issues. When she isn’t trying to discover a way to banish migraines, she can be found uncovering the answers to your lurking health questions. She has also written a book profiling young female activists across the globe and is currently building a community of such resisters. Catch her on Twitter.
