Unsweetened coffee and tea are linked to lower heart disease risk, with people drinking 2-3 cups of unsweetened coffee daily showing about 19% lower cardiovascular disease risk in a study of 167,142 people followed for 11 years. According to Gram Research analysis, adding sugar or sweeteners eliminates this protective benefit, and high amounts of sweetened tea actually increased heart disease risk by 13%. The type of beverage matters less than whether you sweeten it.
A major study of over 167,000 people found that drinking unsweetened coffee and tea is linked to a lower risk of heart disease, but adding sugar or sweeteners removes this benefit. Researchers tracked participants for more than 11 years and discovered that people who drank 2-3 cups of unsweetened coffee daily had about 19% lower heart disease risk compared to non-drinkers. Interestingly, sweetened versions of these drinks showed no protective benefit, and drinking too much sweetened tea was actually associated with higher heart disease risk. According to Gram Research analysis, the type of beverage matters less than what you add to it.
Key Statistics
A 2026 prospective cohort study of 167,142 UK Biobank participants found that people drinking 2-3 cups of unsweetened coffee daily had a 19% lower risk of developing cardiovascular disease compared to non-drinkers over an 11-year follow-up period.
Among 14,395 cardiovascular disease cases identified during the study, those consuming more than 5 cups of sweetened tea daily had a 13% higher heart disease risk compared to non-drinkers, while unsweetened tea showed consistent protective benefits across all intake levels.
The same 2026 cohort study revealed that sweetened coffee consumption showed no protective association with cardiovascular disease at any intake level, suggesting that added sweeteners eliminate the heart-health benefits of coffee’s natural compounds.
The Quick Take
- What they studied: Whether drinking coffee and tea—with or without sweeteners—affects the risk of developing heart disease, stroke, or heart failure
- Who participated: 167,142 people from the UK Biobank study who didn’t have heart disease at the start, tracked for an average of 11.1 years
- Key finding: Unsweetened coffee and tea were linked to lower heart disease risk, with the biggest benefit at 2-3 cups daily (19% lower risk for coffee). Adding sugar or sweeteners eliminated this protective effect, and high amounts of sweetened tea actually increased risk by 13%.
- What it means for you: If you drink coffee or tea, keeping them unsweetened appears to be better for your heart. This doesn’t mean you must drink these beverages, but if you do, skipping the sugar and sweeteners may provide cardiovascular benefits. Individual results vary, and people with specific health conditions should consult their doctor.
The Research Details
This was a prospective cohort study, meaning researchers followed a large group of people over time and tracked what happened to their health. The study included 167,142 people from the UK Biobank who didn’t have heart disease when they joined. Researchers asked participants multiple times (using online 24-hour dietary recalls) what they ate and drank, including whether they added sweeteners to their coffee and tea. Over 11 years, researchers recorded who developed heart disease, stroke, or heart failure.
The researchers used statistical methods to compare heart disease rates between people who drank different amounts of sweetened versus unsweetened coffee and tea. They adjusted their analysis to account for other factors that affect heart disease risk, like age, smoking, exercise, and diet quality. This approach helps isolate the effect of the beverages themselves.
Most previous studies didn’t distinguish between sweetened and unsweetened beverages, which may explain why earlier research gave mixed results. By separating these groups, this study reveals that sweetener use is crucial to understanding whether coffee and tea are heart-healthy. This is important because millions of people drink these beverages daily, and knowing how to prepare them for maximum benefit is practical health information.
This study has several strengths: it’s large (over 167,000 participants), followed people for over a decade, and used repeated dietary assessments rather than asking people to remember their habits from years ago. The study was published in a peer-reviewed journal (European Journal of Nutrition). However, the study is observational, meaning it shows associations but cannot prove that unsweetened coffee causes lower heart disease risk—other unmeasured factors could explain the link. The UK Biobank participants are primarily white and British, so findings may not apply equally to all populations.
What the Results Show
During the 11-year follow-up period, 14,395 participants (about 8.6%) developed heart disease, stroke, or heart failure. For unsweetened coffee, the relationship with heart disease risk followed a U-shaped curve: people who drank small to moderate amounts had the lowest risk, while those drinking very large amounts showed no additional benefit. Specifically, people drinking 2-3 cups of unsweetened coffee daily had a 19% lower heart disease risk compared to non-drinkers. Those drinking 1-2 cups had a 10% lower risk, and those drinking 3-5 cups had a 14% lower risk.
Unsweetened tea showed consistent benefits across all intake levels—the more unsweetened tea people drank, the lower their heart disease risk. In contrast, sweetened coffee showed no protective benefit at any consumption level. Sweetened tea was particularly concerning: people drinking more than 5 cups daily had a 13% higher heart disease risk compared to non-drinkers.
The difference between sweetened and unsweetened versions was striking. The same beverage that protected the heart when unsweetened provided no benefit when sweetened, suggesting that added sugars or artificial sweeteners may counteract the positive effects of coffee and tea compounds.
The study found that the relationship between unsweetened coffee and heart disease risk was non-linear, meaning more wasn’t always better. Beyond 5 cups daily, additional coffee consumption didn’t provide extra protection. This suggests an optimal range rather than a ‘more is better’ scenario. The findings were consistent across different types of cardiovascular events (heart attack, stroke, and heart failure), indicating that the beverage effect applies broadly to heart health rather than just one condition.
Earlier research on coffee and tea produced conflicting results, with some studies suggesting benefits and others finding no effect or even harm. This inconsistency likely occurred because previous studies didn’t account for sweetener use. By separating sweetened from unsweetened beverages, this research clarifies why earlier studies were contradictory—they were essentially mixing two different exposures (protective unsweetened drinks and neutral or harmful sweetened drinks) together. This study aligns with emerging evidence that added sugars are a major driver of cardiovascular disease risk, and suggests that the natural compounds in coffee and tea (like polyphenols and antioxidants) may be beneficial, but only when not masked by sweeteners.
The study cannot prove cause-and-effect; it only shows associations. People who drink unsweetened coffee might differ in other healthy habits from those who drink sweetened coffee, and these differences could explain the results. The study population was primarily white and British, so results may not apply equally to other ethnic groups or countries with different coffee and tea preparation traditions. Dietary information came from self-reports, which can be inaccurate. The study didn’t measure specific types of sweeteners (sugar versus artificial sweeteners), so we don’t know if different sweeteners have different effects. Finally, the study measured beverages at specific time points, but people’s drinking habits may have changed during the 11-year follow-up period.
The Bottom Line
If you currently drink coffee or tea, consuming unsweetened versions appears to offer cardiovascular benefits, with an optimal range of 2-5 cups daily. If you add sweeteners, consider gradually reducing or eliminating them to potentially gain the heart-protective benefits. This recommendation has moderate confidence based on a large, long-term study, though it’s not a guarantee for any individual. If you don’t currently drink coffee or tea, this research doesn’t suggest you should start—the benefits apply to people who already consume these beverages.
This research is most relevant to people who regularly drink coffee or tea and want to optimize their cardiovascular health. It’s particularly important for people with family histories of heart disease, those with existing cardiovascular risk factors, or anyone interested in dietary approaches to heart health. People with caffeine sensitivity, anxiety disorders, or certain medical conditions should consult their doctor before increasing coffee consumption. The findings don’t apply to children or pregnant women, who should limit caffeine intake regardless.
The cardiovascular benefits of switching to unsweetened beverages likely develop gradually over months to years, not days or weeks. The study tracked people over 11 years, suggesting that consistent long-term habits matter more than short-term changes. You might notice other benefits (like better energy levels or reduced sugar crashes) within days or weeks of reducing sweeteners, but heart disease risk reduction requires sustained changes over months and years.
Frequently Asked Questions
Is coffee good for your heart?
Unsweetened coffee appears beneficial for heart health, with 2-3 cups daily associated with 19% lower cardiovascular disease risk in a large study. However, adding sugar or sweeteners eliminates this benefit. The natural compounds in coffee seem protective, but sweeteners counteract them.
Does sweetened tea increase heart disease risk?
High intake of sweetened tea (more than 5 cups daily) was associated with 13% higher heart disease risk in a study of 167,000 people. Unsweetened tea, by contrast, showed consistent cardiovascular benefits. The added sweetener appears to be the harmful factor.
How much coffee should I drink daily for heart health?
Research suggests 2-5 cups of unsweetened coffee daily may offer cardiovascular benefits, with the strongest protection at 2-3 cups. Beyond 5 cups, additional coffee provided no extra benefit. Individual tolerance varies, so consult your doctor about what’s appropriate for you.
Can I use artificial sweeteners in my coffee or tea?
This study didn’t distinguish between sugar and artificial sweeteners, so we don’t know if they have different effects. The research showed that any sweetened version—whether with sugar or artificial sweeteners—didn’t provide the heart-protective benefits of unsweetened beverages.
What’s the best way to switch from sweetened to unsweetened coffee?
Gradual reduction works better than quitting abruptly. Try reducing sweetener by 25% each week over a month, allowing your taste buds to adjust. Many people find that after 2-4 weeks, unsweetened coffee tastes normal, and they no longer crave the sweetness.
Want to Apply This Research?
- Track daily cups of unsweetened coffee and tea separately from sweetened versions. Set a target range of 2-5 cups of unsweetened beverages daily and monitor whether you’re staying within this range. Log the type of sweetener used (if any) and the amount, allowing you to see patterns in your consumption.
- If you currently sweeten your coffee or tea, use the app to gradually reduce sweetener amounts over 2-4 weeks rather than quitting cold turkey. For example: Week 1, use 75% of your normal sweetener amount; Week 2, use 50%; Week 3, use 25%; Week 4, try unsweetened. The app can send reminders to try unsweetened versions and celebrate milestones when you successfully reduce sweetener use.
- Create a long-term tracking dashboard showing your weekly average of unsweetened versus sweetened beverage consumption. Set a goal to reach 80% unsweetened beverages within 8 weeks. Use the app’s trend analysis to show how your consumption patterns change over months, reinforcing the habit change. Connect this tracking to other cardiovascular health metrics (like blood pressure or exercise) to see correlations with your beverage choices.
This research shows associations between beverage consumption and heart disease risk but does not prove cause-and-effect. Individual responses to coffee and tea vary based on genetics, existing health conditions, medications, and overall lifestyle. People with caffeine sensitivity, anxiety disorders, high blood pressure, pregnancy, or specific medical conditions should consult their healthcare provider before changing coffee or tea consumption. This information is not a substitute for professional medical advice, diagnosis, or treatment. Always discuss dietary changes with your doctor, especially if you have existing cardiovascular disease or risk factors.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.