A 2026 cohort study of 1,953 Iranian adults found that higher salt and potassium levels in urine were not significantly associated with heart disease events during a two-year follow-up, despite being linked to other heart risk factors like high blood pressure and obesity. According to research reviewed by Gram, while these minerals affect blood pressure and other cardiovascular risk factors, measuring them in urine alone may not reliably predict who will develop heart disease in the short term.
Researchers tracked 1,953 Iranian adults for two years to see if the amount of salt and potassium in their urine could predict heart problems. They measured these minerals in morning urine samples and followed participants to see who developed heart disease. While high salt and potassium levels were linked to other heart risk factors like high blood pressure and obesity, they didn’t actually predict who would have heart events during the study. The findings suggest we need longer studies and better ways to measure what people eat to understand how these minerals truly affect heart health.
Key Statistics
A 2026 cohort study of 1,953 Iranian adults found no significant associations between estimated 24-hour urinary sodium and potassium excretion and cardiovascular events during two-year follow-up, despite associations with blood pressure and other risk factors.
In the Isfahan Cohort Study of 1,953 participants, higher sodium excretion was associated with higher blood pressure and male sex, but did not predict actual heart disease events in the adjusted analysis.
A 2026 analysis of 1,953 Iranian adults showed that potassium excretion displayed a nonlinear pattern with cardiovascular risk, with the middle tertile having the highest hazard ratio rather than the highest tertile.
The Quick Take
- What they studied: Whether measuring salt and potassium in urine samples could predict who would develop heart disease or have heart attacks
- Who participated: 1,953 adults living in Isfahan, Iran, with an average age around 50 years old, followed for two years starting in 2013
- Key finding: Higher salt and potassium in urine were connected to heart risk factors like high blood pressure and obesity, but did not predict actual heart disease events during the two-year study period
- What it means for you: Urine tests for salt and potassium alone may not be reliable for predicting your personal heart disease risk. Doctors still need to look at other factors like blood pressure, weight, and lifestyle. This doesn’t mean salt and potassium don’t matter for heart health, just that we need better studies to understand their true impact.
The Research Details
This was a historical cohort study, meaning researchers looked back at data they had already collected. In 2013, they collected morning urine samples from 1,953 Iranian adults and measured how much salt and potassium each person was excreting (losing through urine). They used a mathematical formula called the Tanaka formula to estimate how much salt and potassium each person consumed based on their urine levels. The researchers then followed these same people for two years to see who developed heart disease or had heart attacks.
The team used statistical methods called Cox proportional hazards models to analyze the data. This fancy name just means they looked at whether people with higher or lower salt and potassium levels were more or less likely to have heart problems. They divided participants into three groups based on their salt and potassium levels (called tertiles) and compared the groups. They also adjusted their analysis to account for other factors that affect heart health, like age, weight, blood pressure, smoking, diabetes, and physical activity.
This approach is useful because it measures actual salt and potassium excretion rather than asking people to remember what they ate. However, the study only lasted two years, which might not be long enough to see the full effects of these minerals on heart disease risk.
Most previous research on salt and potassium relied on either blood tests or asking people what they ate, both of which can be inaccurate. Measuring these minerals in urine is more objective because it shows what your body is actually processing. If urine measurements could predict heart disease, doctors might use simple urine tests to identify people at high risk. However, this study found that connection wasn’t as strong as expected, suggesting we need to rethink how we measure and predict heart disease risk.
This study has several strengths: it included a large number of participants, used objective urine measurements rather than dietary recall, and adjusted for many other heart disease risk factors. However, there are important limitations. The study only lasted two years, which may be too short to see heart disease develop. The participants were all from one region of Iran, so results may not apply to other populations. The study used an estimated formula to calculate salt and potassium rather than direct measurement, which introduces some uncertainty. Additionally, the study found no significant associations, which means we cannot draw strong conclusions about whether these minerals predict heart disease.
What the Results Show
The main finding was surprising: higher salt and potassium in urine were not significantly associated with heart disease events during the two-year follow-up period. However, the researchers did notice a trend where people with higher salt levels had slightly higher risk of heart problems, though this trend was not statistically significant (meaning it could have happened by chance).
Interestingly, people with higher salt in their urine did have more heart risk factors. They tended to be male, have higher body weight, higher blood pressure, and higher blood sodium and potassium levels. They also had better diet quality scores and were more physically active, which seems contradictory. This suggests that salt excretion is complicated and linked to many different factors.
People with higher potassium in their urine showed a different pattern. They tended to be younger, male, have higher triglycerides (a type of blood fat), and higher blood electrolytes. Interestingly, fewer of them smoked, but more had diabetes. The relationship between potassium and heart risk was nonlinear, meaning it didn’t follow a simple pattern. The middle group of potassium excretion actually had the highest risk, not the highest group.
Overall, while salt and potassium excretion were linked to various heart risk factors, they did not predict who actually had heart events in this study. This disconnect between risk factors and actual events is important and suggests that short-term studies may not capture the true long-term effects of these minerals.
The study revealed several interesting secondary findings about who excretes more salt and potassium. Men consistently excreted more of both minerals than women. People with higher body weight excreted more salt and potassium. The relationship between these minerals and blood pressure was notable: higher salt excretion was associated with higher blood pressure, which makes sense because salt affects blood pressure. Surprisingly, people with higher salt excretion reported better diet quality, which contradicts the common belief that high salt intake means poor diet quality. This may reflect that the study population had generally good health awareness.
Previous research has strongly linked high salt intake to high blood pressure and heart disease risk. This study confirms that salt excretion is associated with blood pressure and other risk factors. However, most previous studies have been shorter or used dietary estimates rather than urine measurements. Gram Research analysis shows that this study adds important evidence that measuring salt in urine may not be as predictive of actual heart disease as we might expect. The finding that potassium showed a nonlinear relationship with risk is also new and suggests the relationship between potassium and heart health is more complex than previously thought. The lack of significant associations with actual heart events contrasts with some previous research but aligns with other studies suggesting that short-term follow-up may not be sufficient to detect cardiovascular outcomes.
This study has several important limitations that readers should understand. First, the follow-up period was only two years, which is relatively short for detecting heart disease. Heart disease develops over many years, so a longer study might show different results. Second, the study used an estimated formula to calculate salt and potassium from urine rather than direct measurement, which introduces some error. Third, all participants were from Isfahan, Iran, so the results may not apply to other populations with different genetics, diets, or healthcare systems. Fourth, the study had relatively few heart disease events during the follow-up period, which makes it harder to detect associations. Finally, the study was observational, meaning researchers observed what happened rather than randomly assigning people to different salt or potassium levels, so we cannot prove cause and effect.
The Bottom Line
Based on this study alone, we cannot recommend using urine salt and potassium tests to predict heart disease risk. However, this does not mean salt and potassium don’t matter for heart health. The established evidence still shows that managing salt intake and getting enough potassium are important for blood pressure control and heart health. Continue following general recommendations: limit salt to less than 2,300 mg per day, eat potassium-rich foods like fruits and vegetables, maintain a healthy weight, exercise regularly, and don’t smoke. Talk to your doctor about your personal heart disease risk based on all your risk factors, not just salt and potassium levels. Confidence level: Moderate. This single study is not strong enough to change current recommendations, but it suggests we need better research methods.
This research matters most to people concerned about heart disease prevention, people with high blood pressure, and healthcare providers looking for better ways to predict heart disease risk. It’s particularly relevant for people in Middle Eastern populations similar to the study group. People with a family history of heart disease should continue following heart-healthy guidelines regardless of this study’s findings. This study should not change your behavior if you’re already following heart-healthy recommendations. However, if you were considering urine tests as a way to assess your heart disease risk, this study suggests that approach may not be reliable on its own.
If you make changes based on heart-healthy recommendations (reducing salt, eating more potassium-rich foods, exercising), you might see improvements in blood pressure within weeks to months. However, the actual prevention of heart disease events takes years or decades. This is why longer studies are needed to truly understand how salt and potassium affect heart disease risk over time.
Frequently Asked Questions
Can a urine test for salt and potassium predict if I’ll have a heart attack?
Not reliably, according to a 2026 study of 1,953 adults. While urine salt and potassium levels were linked to heart risk factors like high blood pressure, they did not predict actual heart disease events during two-year follow-up. Your doctor should assess heart disease risk using multiple factors.
Does high salt in urine mean I have high blood pressure?
High salt excretion in urine is associated with higher blood pressure, but the connection is not perfect. Many factors affect both salt excretion and blood pressure. The best way to know your blood pressure is to have it measured directly by a healthcare provider, not through urine tests.
Should I change my salt and potassium intake based on this research?
This single study doesn’t change current recommendations. Continue limiting salt to under 2,300 mg daily and eating potassium-rich foods like fruits and vegetables. These changes help control blood pressure, which is proven to reduce heart disease risk over time.
Why didn’t the study find that salt and potassium predict heart disease?
The two-year follow-up period was likely too short to detect heart disease development, which takes years or decades. The study also used estimated measurements rather than direct testing. Longer studies with better measurement methods are needed to clarify these relationships.
Is potassium protective against heart disease like the study suggests?
The study found a complex, nonlinear relationship where the middle potassium level had the highest risk, not the highest level. This suggests potassium’s role in heart health is more complicated than previously thought and requires more research to understand.
Want to Apply This Research?
- Track your daily salt intake (aim for under 2,300 mg per day) and potassium-rich foods consumed (aim for 2,600 to 3,400 mg per day). Log these daily and review weekly trends to see if you’re meeting targets.
- Use the app to set a reminder to check nutrition labels for sodium content before eating packaged foods. Create a shopping list of potassium-rich foods like bananas, sweet potatoes, spinach, and beans. Track which meals are highest in salt and identify opportunities to reduce sodium while maintaining flavor through herbs and spices.
- Measure and log your blood pressure weekly at the same time of day. Track this alongside your salt and potassium intake to see if dietary changes correlate with blood pressure improvements. Over months, you should see patterns emerge showing how your personal diet affects your blood pressure, which is a more direct measure of heart health than urine tests.
This research describes associations between urinary salt and potassium and heart disease risk in a specific Iranian population over two years. These findings should not replace personalized medical advice from your healthcare provider. Do not use urine tests alone to assess your heart disease risk. If you have concerns about your heart health, high blood pressure, or family history of heart disease, consult your doctor for a comprehensive risk assessment. Current evidence still supports limiting salt intake and consuming adequate potassium as part of heart-healthy living, regardless of this study’s findings. Always discuss dietary changes with your healthcare provider, especially if you have kidney disease or take medications affecting potassium levels.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.