Researchers discovered something surprising: when some people eat a high-salt diet, their blood pressure actually goes down instead of up. In a small study of 20 adults, scientists found that a protein called SVEP1 might explain why different people react differently to salt. When people ate more salt, those whose bodies made more SVEP1 had lower blood pressure. This discovery could help doctors understand why salt affects people so differently and might eventually help identify who needs to watch their salt intake and who doesn’t.
The Quick Take
- What they studied: How eating different amounts of salt affects blood pressure and which proteins in the blood change when people eat more or less salt.
- Who participated: 20 healthy adults with normal blood pressure who agreed to eat very low-salt meals for 8 days, then very high-salt meals for 8 days.
- Key finding: Surprisingly, when these participants ate more salt, their blood pressure actually decreased slightly. A protein called SVEP1 increased when people ate more salt, and people with higher SVEP1 levels had the biggest blood pressure drops.
- What it means for you: This suggests that not everyone needs to strictly limit salt the same way. Your body might have natural ways to handle extra salt through proteins like SVEP1. However, this is early research in a small group, so don’t change your salt habits yet without talking to your doctor.
The Research Details
This was a carefully controlled experiment where 20 adults followed two different diets in random order. For 8 days, they ate a very low-salt diet (similar to what doctors recommend for people with high blood pressure). Then, after a break, they ate a very high-salt diet for another 8 days. The researchers measured blood pressure and analyzed about 7,000 different proteins in the participants’ blood to see what changed. By comparing the two diets, they could see which proteins responded to salt and how those changes related to blood pressure changes.
The study used advanced technology called proteomics, which is like taking a detailed snapshot of thousands of proteins at once. This allowed researchers to discover proteins they might not have looked for otherwise. The study was ‘randomized,’ meaning participants didn’t know which diet order they’d follow, which helps prevent bias in the results.
Understanding why people react differently to salt is important because high blood pressure affects millions of people. If doctors could identify which proteins predict salt sensitivity, they might someday be able to tell patients whether they personally need to limit salt. This could help people make better dietary choices based on their individual biology rather than one-size-fits-all recommendations.
This study has both strengths and limitations. The strength is that it was carefully controlled—researchers knew exactly how much salt people ate each day. The main limitation is the very small sample size of only 20 people, which means the findings might not apply to everyone. The study was also short (8 days per diet), so we don’t know if these effects last longer. Additionally, all participants had normal blood pressure to start, so we don’t know if these findings apply to people with high blood pressure. The findings are interesting but should be considered preliminary until larger studies confirm them.
What the Results Show
The most striking finding was that participants’ blood pressure actually went down when they ate more salt, which is opposite to what usually happens. Their diastolic blood pressure (the bottom number) dropped from 69.7 to 67.0 mm Hg, and their mean arterial pressure (an average of blood pressure throughout the heart’s cycle) dropped from 84.8 to 82.1 mm Hg. This pattern is called ‘inverse salt sensitivity.’
The key discovery was that a protein called SVEP1 was the second-most important protein that changed in response to salt (out of about 7,000 proteins measured). When people ate more salt, their SVEP1 levels increased. Importantly, people whose SVEP1 increased the most had the biggest drops in blood pressure. This strong connection suggests SVEP1 plays a real role in how the body responds to salt.
The researchers also found that SVEP1 changes were closely linked to another well-known heart protein called NT-proBNP, suggesting they work together. This connection to an established protein makes SVEP1’s role more believable. The study also found that the body’s response to extra salt involved changes in the extracellular matrix—the structural material that supports blood vessels—suggesting the body remodels its blood vessel structure in response to salt.
Participants gained about 1.4 kilograms (3 pounds) when eating the high-salt diet, which makes sense because salt causes the body to retain water. Interestingly, this weight gain happened even though blood pressure went down, showing that water retention and blood pressure response are separate processes. The study also showed that well-known salt-regulating hormones like renin ranked much lower than SVEP1 in importance, suggesting SVEP1 might be a more important player than previously recognized.
Most previous research shows that eating more salt increases blood pressure in most people (called salt sensitivity). However, some people show little response to salt (salt resistance), and a small number actually show the opposite effect (inverse salt sensitivity), like the participants in this study. This research is the first to identify SVEP1 as a key protein in these different responses. The finding that the body remodels its blood vessel structure in response to salt aligns with previous research showing that the body has multiple ways to adapt to dietary changes.
The study is quite small with only 20 participants, so results might not apply to everyone. All participants had normal blood pressure, so we don’t know if these findings apply to people with high blood pressure or those taking blood pressure medications. The study lasted only 8 days per diet, which is relatively short—we don’t know if these effects continue over weeks or months. The study didn’t include diverse populations, so we don’t know if SVEP1’s role is the same across different ethnic groups or ages. Finally, this is observational research showing correlation (SVEP1 and blood pressure changes happen together), not proof that SVEP1 causes the blood pressure changes.
The Bottom Line
At this stage, these findings are too preliminary to change anyone’s salt habits. If you have normal blood pressure, current guidelines still recommend moderate salt intake (less than 2,300 mg per day). If you have high blood pressure, continue following your doctor’s recommendations about salt restriction. In the future, if SVEP1 testing becomes available, it might help personalize salt recommendations, but that’s not yet possible. Confidence level: Low—this is early-stage research that needs confirmation in larger studies.
This research is most relevant to people interested in personalized medicine and those with high blood pressure who wonder if they personally need strict salt limits. It’s also important for researchers studying blood pressure regulation. People with normal blood pressure don’t need to change anything based on this study. People taking blood pressure medications should definitely not change their salt intake without consulting their doctor.
If SVEP1 testing eventually becomes available as a clinical tool, it would likely take 5-10 years of additional research and development. In the meantime, this research is laying groundwork for future personalized approaches to salt intake recommendations.
Want to Apply This Research?
- Track daily salt intake (in milligrams) alongside blood pressure readings taken at the same time each day. Most apps can log sodium from food entries and correlate it with blood pressure trends over 2-4 week periods to see your personal pattern.
- Use the app to experiment with your personal salt sensitivity by tracking blood pressure during a week of lower salt intake (under 2,000 mg/day) and a week of moderate salt intake (2,300-3,000 mg/day). Record how you feel and any blood pressure changes to understand your individual response.
- Set up weekly blood pressure tracking at the same time each day (morning is best) and log daily sodium intake from food labels. Over 8-12 weeks, review trends to see if your blood pressure correlates with salt intake. Share patterns with your doctor to determine if you’re salt-sensitive or salt-resistant.
This research is preliminary and based on a very small study of 20 healthy adults. These findings should not be used to change your salt intake or blood pressure management without consulting your healthcare provider. If you have high blood pressure or take blood pressure medications, continue following your doctor’s recommendations. SVEP1 testing is not currently available for clinical use. This article is for educational purposes only and does not constitute medical advice.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.