Researchers studied over 3,400 adults in Iran to understand how money, lifestyle choices, and what people eat affect heart disease risk. They found that people with higher income had lower heart disease risk, and those who exercised regularly and slept well were also better protected. Interestingly, the foods people chose to eat played an important role in connecting these lifestyle factors to heart health. The study suggests that improving diet quality and making sure everyone has access to healthy food could help reduce heart disease across all income levels.

The Quick Take

  • What they studied: How money, daily habits (exercise and sleep), and food choices work together to affect someone’s risk of developing heart disease
  • Who participated: 3,452 adults between ages 35 and 70 living in western Iran who were part of a long-term health study
  • Key finding: People with more money had 28% lower heart disease risk, and those with good habits like regular exercise and adequate sleep had 27% lower risk. The foods people ate—especially those that spike blood sugar quickly—played a middle role in connecting these factors to heart health
  • What it means for you: Your heart health depends on multiple connected factors: financial stability, daily habits, and food choices. Even if you can’t change your income, improving exercise, sleep, and diet quality may help reduce your heart disease risk

The Research Details

This study looked at information collected from 3,452 adults at one point in time (called a cross-sectional study). Researchers measured people’s height and weight, asked about their income and job, tracked their exercise and sleep habits, recorded any diseases they had, and analyzed what they typically ate. They then used a special statistical method called structural equation modeling—think of it like mapping out how different factors connect to each other—to see which paths led to higher or lower heart disease risk.

The researchers focused on two specific dietary measures: how much foods in someone’s diet cause insulin spikes (a hormone that controls blood sugar), and how much foods cause blood sugar spikes directly. These dietary measures acted like bridges, showing how lifestyle and money indirectly affect heart health through food choices.

The study was conducted in western Iran as part of a larger, ongoing health project called the Dehgolan Prospective Cohort Study, which follows people’s health over many years.

This approach is important because heart disease doesn’t happen from just one cause—it results from many connected factors working together. By mapping out these connections, researchers can identify the most important intervention points. Understanding that diet quality acts as a bridge between socioeconomic factors and heart health suggests that improving food access and nutrition education could be powerful public health tools.

The study included a large number of participants (3,452), which makes the findings more reliable. However, because this was a snapshot in time rather than following people forward, we can’t prove that these factors directly cause heart disease—only that they’re associated with it. The statistical model explained only 11% of heart disease risk, meaning many other important factors weren’t measured. The study was conducted in Iran, so results may not apply equally to all populations worldwide.

What the Results Show

The research revealed that higher socioeconomic status (having more money and resources) directly reduced heart disease risk by about 28%. This was the strongest protective effect found in the study. People with better personal habits—specifically those who exercised regularly and got adequate sleep—had about 27% lower heart disease risk compared to those with poor habits.

When looking at diet, foods that cause rapid blood sugar spikes (measured by the Dietary Glycemic Index) showed a small protective effect, reducing risk by 3%. However, foods that trigger high insulin responses (measured by the Dietary Insulin Index) increased heart disease risk by 15%, which was a meaningful effect.

The study also found indirect pathways: socioeconomic status, personal habits, and existing chronic diseases all influenced heart disease risk partly through their effects on dietary choices. In other words, people’s food choices helped explain why money, exercise, and sleep mattered for heart health.

Higher socioeconomic status also reduced the burden of chronic diseases (like diabetes) by 21%, which itself contributed to lower heart disease risk. The presence of chronic diseases increased heart disease risk through multiple pathways, both directly and by influencing dietary patterns. Personal habits like exercise and sleep had strong direct protective effects, suggesting these behaviors matter for heart health independent of diet.

These findings align with decades of research showing that exercise, sleep, and diet quality protect heart health. The study adds new insight by showing how these factors interconnect—that diet quality may be one mechanism through which socioeconomic status and lifestyle habits affect heart disease. Previous research has separately studied these factors; this study’s strength is showing how they work together.

The study was conducted at one point in time, so we cannot determine whether these factors actually cause heart disease or just appear together. The statistical model explained only 11% of heart disease risk, meaning 89% is influenced by factors not measured in this study (like genetics, stress, air pollution, or medical care quality). Results come from a specific population in Iran and may not apply equally to other countries or ethnic groups. The study relied on people’s reports of their diet and habits, which can be inaccurate. Finally, this was an observational study, not an experiment, so we cannot make definitive cause-and-effect claims.

The Bottom Line

Based on this research (moderate confidence): Focus on improving diet quality by choosing foods that don’t spike blood sugar rapidly. Aim for at least 150 minutes of moderate exercise weekly and 7-9 hours of sleep nightly. If possible, work toward financial stability and access to healthy foods, as these provide strong protection. These recommendations are supported by extensive previous research and this study’s findings.

Adults aged 35 and older should pay attention to these findings, especially those with family history of heart disease, existing high blood pressure, or diabetes. People with lower incomes should know that improving diet and exercise habits may help offset some financial barriers to healthcare. Healthcare providers should consider these interconnected factors when counseling patients about heart disease prevention.

Improvements in exercise and sleep habits may improve heart health markers (like blood pressure) within 2-4 weeks. Dietary changes may show benefits in blood sugar control within 4-8 weeks. Significant reductions in heart disease risk typically take months to years of consistent healthy habits. Financial stability improvements take longer but provide sustained protection.

Want to Apply This Research?

  • Track three daily metrics: (1) minutes of moderate exercise, (2) hours of sleep, and (3) a simple diet quality score based on blood-sugar-spiking foods consumed. Users could rate each meal on a 1-5 scale for how much it likely spikes blood sugar, then track weekly averages.
  • Set a specific goal like ‘Exercise 30 minutes, 5 days per week’ and ‘Sleep 7-8 hours nightly.’ For diet, users could identify and reduce their top three blood-sugar-spiking foods (like sugary drinks, white bread, or processed snacks) and replace them with alternatives. The app could send reminders for exercise and sleep targets.
  • Weekly review of exercise minutes, sleep hours, and diet quality scores. Monthly tracking of how these three factors correlate with energy levels and any available health metrics (blood pressure if user has a monitor). Quarterly goal adjustment based on progress and consistency.

This research suggests associations between lifestyle factors and heart disease risk but does not prove cause-and-effect relationships. The findings come from one population in Iran and may not apply equally to all groups. This information is educational and should not replace personalized medical advice from your doctor. Before making significant changes to exercise, diet, or if you have concerns about heart disease risk, consult with a healthcare provider who knows your complete medical history. If you experience chest pain, shortness of breath, or other heart attack symptoms, seek emergency medical care immediately.