الوسم: stroke risk

  • Light Exercise Can Reduce Stroke Risk in Atrial Fibrillation Patients

    Light Exercise Can Reduce Stroke Risk in Atrial Fibrillation Patients

    Credit: Unsplash+


    Engaging in regular physical activity is widely recognized for its heart-strengthening benefits, but many individuals with atrial fibrillation worry that exercising might be risky.

    Recent research indicates the opposite may be true. Staying active has been associated with a decreased likelihood of stroke and increased longevity, even among those living with this common arrhythmia.

    Atrial fibrillation occurs when the heart’s upper chambers beat rapidly and irregularly. This irregular heartbeat can cause blood to stagnate inside the heart, raising the risk of clot formation. If a clot travels to the brain, it can block blood flow, leading to a stroke.

    Researchers at UiT The Arctic University of Norway aimed to explore whether physical activity influences these risks. They examined health data from over 87,000 adults involved in two large Norwegian population studies and tracked their health outcomes for approximately 15 years.

    Participants reported their exercise routines, including frequency, duration, and intensity. Throughout the follow-up period, researchers documented newly diagnosed AFib cases, strokes, and mortality rates using national health records.

    The findings consistently showed benefits for those who remained active. Compared to inactive individuals, active participants had a lower risk of both stroke and death, even after adjusting for various other health factors.

    Those engaging in moderate activity experienced the greatest reduction in stroke risk, while the highest levels of activity were linked to the most significant decrease in overall mortality. Even small amounts of exercise offered noticeable health advantages.

    This trend persisted among individuals with AFib. Staying physically active was associated with an estimated lifespan extension of roughly half a year to 1.2 years compared to inactive counterparts with the same condition.

    Dr. Kristoffer Johansen, the lead researcher, emphasized that these results should motivate both healthcare providers and patients, as substantial health improvements can be achieved with modest exercise. There’s no need to become an athlete to reap the benefits.

    Current guidelines recommend at least 150 minutes of moderate activity weekly or 75 minutes of vigorous exercise, along with strength training twice a week. Activities like walking, cycling, swimming, dancing, and gardening can all help meet these goals.

    However, the researchers note that their study cannot definitively prove exercise directly prevented strokes, as it was observational. People who exercise regularly may also have healthier diets, avoid smoking, or possess other beneficial habits. Additionally, activity levels were self-reported by participants.

    This study was published in the Journal of the American Heart Association.

    It stands as one of the largest long-term investigations into exercise and AFib, strengthening confidence in the findings thanks to its size and extended follow-up. Yet, randomized controlled trials would be necessary to establish a direct cause-and-effect relationship.

    Despite these limitations, the evidence suggests that regular physical activity likely plays a vital role in maintaining heart health for individuals with or without AFib.

    Source: UiT The Arctic University of Norway.


  • Surprising Stroke Risk Linked to Popular Sugar-Free Sweetener

    Surprising Stroke Risk Linked to Popular Sugar-Free Sweetener

    Many individuals opt for sugar-free foods and beverages to shed pounds, cut down on sugar, or better manage their blood sugar levels. These products, often labeled as “low sugar,” “keto,” or “diabetic-friendly,” typically contain artificial or low-calorie sweeteners instead of traditional sugar.

    Erythritol is among the most common of these sweeteners. It’s found in a variety of items such as sugar-free sodas, protein bars, chewing gum, low-carb desserts, ice cream, baked goods, and numerous packaged snacks.

    As a sugar alcohol, erythritol provides a sweet taste with almost no calories and minimal impact on blood sugar or insulin levels, despite its name suggesting alcohol content. Because of these benefits, erythritol has been considered an effective alternative to sugar for years and is widely used by people with diabetes, those on low-carb diets, and anyone looking to lower calorie intake.

    Recently, scientists have begun scrutinizing whether erythritol is as harmless as once thought. Emerging research indicates that this sweetener might have unexpected effects on cardiovascular health, particularly on the heart and blood vessels.

    A study from the University of Colorado Boulder raises concerns by suggesting erythritol could elevate stroke risk by disrupting healthy blood vessel function in the brain. Published in the Journal of Applied Physiology, the study was led by Professor Christopher DeSouza and graduate researcher Auburn Berry, who aimed to understand why earlier population studies linked erythritol to heart problems.

    Interest in erythritol surged after a prior large-scale study involving about 4,000 individuals across the U.S. and Europe found that higher blood levels of erythritol were associated with a greater likelihood of heart attack or stroke over three years. However, that study couldn’t clarify how erythritol might increase such risks.

    To explore this further, researchers conducted lab experiments using human brain blood vessel cells. They exposed these cells to erythritol amounts comparable to what someone might consume from a single sugar-free drink. Although these tests were done in a lab setting, several changes observed could potentially raise stroke risk.

    One key discovery involved nitric oxide, a natural compound produced by blood vessel lining cells. Nitric oxide aids blood vessels in relaxing and expanding, which helps maintain smooth blood flow. The cells exposed to erythritol produced less nitric oxide, implying that blood vessels might become less capable of proper dilation.

    At the same time, the cells produced more endothelin-1, a protein that has the opposite effect by causing blood vessels to constrict and narrow. This combination of lower nitric oxide and higher endothelin-1 could make vessels stiffer, narrower, and less adaptable to the body’s needs.

    The study also found that erythritol appeared to interfere with the body’s ability to dissolve blood clots naturally. Typically, blood vessel cells release tissue plasminogen activator (t-PA), a substance that helps break down clots before they become problematic. After erythritol exposure, cells produced less t-PA, potentially making blood clots more likely to form and cause blockages in the brain.

    Furthermore, the treated cells showed increased levels of free radicals—unstable molecules that can damage cells, promote inflammation, and contribute to cardiovascular disease development over time. Elevated oxidative stress from free radicals is a known factor in blood vessel and tissue damage.

    Auburn Berry explained that when blood vessels become more constricted and less efficient at removing clots, the risk of stroke could rise. The study suggests erythritol might contribute to stroke risk by mechanisms such as these, providing biological explanations for earlier observed associations.

    The researchers emphasized that only one serving of erythritol was tested. Professor DeSouza noted that many people consume multiple servings daily, which could lead to significantly higher exposure than what was studied.

    It’s important to recognize the study’s limitations: these experiments involved human cells grown in a laboratory, not live subjects. Consequently, they can’t establish a direct cause-and-effect link between erythritol intake and strokes in real life. Substantial further research, especially controlled human studies, is needed to understand the long-term health effects of erythritol.

    Despite these findings, the evidence underscores the need for ongoing investigation into low-calorie sweeteners. Consumers are advised to read food labels carefully and monitor their intake of erythritol and other sugar alcohols in their diets.

    While these sweeteners can help reduce sugar consumption, they may also have health impacts that scientists are just beginning to explore. As new research emerges, maintaining moderation and making informed choices remain prudent.

    For those concerned about stroke risk, paying attention to dietary habits that help prevent strokes—including diets rich in flavonoids—can be beneficial. Studies suggest that a Mediterranean diet and foods like wild blueberries may support brain and heart health.