A large study of South Korean adults found that people who understand health information better are less likely to develop prehypertension, which is when blood pressure starts getting too high but isn’t quite at dangerous levels yet. Researchers looked at nearly 1,900 adults and discovered that those with low health literacy—meaning they struggle to understand health information—were 43% more likely to have prehypertension. The good news is that health literacy is something people can improve through education and better access to clear health information. This suggests that teaching people how to understand and use health information might be an important way to prevent serious heart problems before they start.
The Quick Take
- What they studied: Whether people who understand health information better are less likely to have prehypertension (the early stage of high blood pressure)
- Who participated: 1,873 South Korean adults aged 19 and older who took a test measuring how well they understand health information
- Key finding: Adults with low health literacy were 43% more likely to have prehypertension compared to those who understood health information well. About 1 in 6 participants had prehypertension, and about 6 in 10 had low health literacy.
- What it means for you: If you struggle to understand health information, you may have a higher risk of developing high blood pressure. Learning more about health topics and asking doctors to explain things clearly could help protect your heart. However, this study shows a connection, not proof that low health literacy causes prehypertension.
The Research Details
This study used data from a large national health survey in South Korea from 2023. Researchers selected a representative sample of nearly 1,900 adults and measured two main things: their health literacy (how well they understand health information) and their blood pressure. They used a special test called the Korean Health Literacy Index to measure health understanding. Blood pressure was measured using standard medical equipment. The researchers then used statistical methods to see if people with lower health literacy were more likely to have prehypertension, while accounting for other factors like age, income, education, and employment status that might also affect blood pressure.
This approach is important because it looks at a large, representative group of real people rather than just patients already being treated for high blood pressure. By studying people before they develop serious hypertension, researchers can identify ways to prevent the disease from developing. The study also looked at whether the connection between health literacy and prehypertension was different for different groups of people, which helps identify who might benefit most from health education programs.
This study used data from an official national health survey, which means the participants represent the general South Korean population fairly well. The researchers adjusted their analysis to account for many other factors that could affect blood pressure, making the results more reliable. However, because this is a cross-sectional study (a snapshot in time), it shows that health literacy and prehypertension are connected but cannot prove that low health literacy causes prehypertension. The results may not apply equally to other countries with different healthcare systems and populations.
What the Results Show
Among the 1,873 adults studied, 319 people (17%) had prehypertension, and 1,098 people (59%) had low health literacy. After accounting for other factors like age, income, and education, the researchers found that people with low health literacy were 43% more likely to have prehypertension than those with high health literacy. This means if you have low health literacy, your risk of prehypertension is notably higher. The relationship was statistically significant, meaning it’s unlikely to have happened by chance. Interestingly, the protective effect of good health literacy wasn’t the same for everyone—it worked differently depending on people’s age, gender, income level, and employment status.
The study identified three possible reasons why health literacy matters for prehypertension: First, people with better health literacy may be more motivated to seek out and use health information to prevent disease. Second, people with good health literacy who also have good resources (like money, living in cities, and good insurance) may have extra protection because they can both understand and access healthcare. Third, health literacy may be especially protective for people who already have low risk of heart disease. These patterns suggest that improving health literacy alone might not be enough—people also need access to healthcare and resources to fully benefit.
Most previous research on health literacy focused on people who already had high blood pressure and whether they took their medicine correctly. This study is different because it looks at prehypertension—the early warning stage—in the general population. This is important because preventing prehypertension from developing into full hypertension is easier and more effective than treating established high blood pressure. The finding that health literacy matters for prevention aligns with other research showing that understanding health information helps people make better health choices.
This study has several important limitations. First, it only shows that health literacy and prehypertension are connected at one point in time; it doesn’t prove that low health literacy causes prehypertension. Second, the study was conducted in South Korea, so the results may not apply to other countries with different healthcare systems, cultures, and populations. Third, the study relied on people’s self-reported health information, which may not always be completely accurate. Fourth, the researchers couldn’t measure all possible factors that might affect blood pressure, so some unmeasured factors could have influenced the results. Finally, the study was cross-sectional, meaning we can’t determine cause and effect.
The Bottom Line
If you have difficulty understanding health information, consider taking steps to improve your health literacy: ask your doctor to explain things in simple terms, use reliable health websites with clear explanations, take a health literacy class if available, and bring a trusted friend or family member to doctor visits to help you understand. Monitor your blood pressure regularly, especially if you have risk factors for high blood pressure. These steps may help reduce your risk of developing hypertension. However, remember that health literacy is just one factor—maintaining a healthy diet, exercising regularly, managing stress, and limiting salt intake are also important. Confidence level: Moderate. This study shows a strong connection, but more research is needed to prove that improving health literacy directly prevents prehypertension.
This research is most relevant for adults who struggle to understand health information, people with family histories of high blood pressure, and public health officials designing prevention programs. It’s especially important for people with lower education levels, lower income, or limited access to healthcare. Healthcare providers should pay attention to this research when counseling patients about heart disease prevention. However, this doesn’t mean people with good health literacy can ignore their blood pressure—everyone should monitor their blood pressure and maintain healthy habits regardless of how well they understand health information.
Improving health literacy is an ongoing process, not something that happens overnight. You might start noticing better understanding of health information within weeks of actively learning. However, changes in blood pressure from improved health literacy would likely take months to appear, as health literacy works by helping you make better daily choices over time. Most people would need to maintain improved health habits for several months to see measurable changes in blood pressure readings.
Want to Apply This Research?
- Track your blood pressure readings weekly at the same time of day, and also track your health learning activities (like reading health articles, watching educational videos, or attending health classes). Note any changes in your readings over 8-12 weeks to see if increased health knowledge correlates with improved blood pressure.
- Use the app to set reminders for daily health learning—spend 10 minutes reading about heart health, blood pressure management, or nutrition. Create a simple glossary within the app to define health terms you don’t understand. Set a goal to ask your doctor three specific questions at your next appointment and record the answers in the app.
- Establish a long-term tracking system that combines blood pressure monitoring with health literacy progress. Monthly, review what health topics you’ve learned and how your blood pressure has changed. Identify which types of health information are most helpful for you and focus on those areas. Share your progress with your healthcare provider to get personalized guidance on which health topics matter most for your individual risk factors.
This research shows a connection between health literacy and prehypertension but does not prove that low health literacy causes prehypertension. The study was conducted in South Korea and may not apply equally to other populations. This information is for educational purposes only and should not replace professional medical advice. If you have concerns about your blood pressure or cardiovascular health, please consult with a qualified healthcare provider. Do not make changes to your healthcare routine based solely on this research without discussing it with your doctor first. This study does not provide medical diagnosis or treatment recommendations for individual patients.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.