Heart Health Archive

Research we're watching

Both heavy drinking and binge drinking (consuming large amounts of alcohol in a single session) are known to increase a person's risk of atrial fibrillation (afib). But even moderate drinking may leave people more prone to the rapid, irregular heart rhythm, a new study suggests.

The report, published online January 9 by the journal Heart Rhythm, included 75 people with afib. Twenty-five were lifelong nondrinkers, 25 were light drinkers (two to seven drinks per week) and 25 were moderate drinkers (eight to 21 drinks weekly). Each participant underwent special tests that generated a three-dimensional map showing electrical and structural changes in their left atria, the heart's upper-left chamber. These changes reflect the severity of afib.

Research we're watching

The more steps you take per day, the more flexible your arteries may be, a new study suggests. Elastic, flexible arteries are a sign of a healthy cardiovascular system, while stiff, inflexible arteries are a harbinger of heart disease.

Researchers pooled findings from 10 studies that measured people's daily step counts and their arterial stiffness, using a technique called pulse wave velocity. With every heartbeat, a wave of blood travels through the body's network of arteries. Measuring the speed of the pulse wave provides information about how stiff or how flexible the arteries are. The stiffer the arteries, the faster this wave travels.

In the journals

People who have had a heart attack or a stroke are routinely prescribed a statin to reduce the risk of a repeat event. But by also following a Mediterranean-style diet, they can improve their chance of living longer, suggests a study in the Feb. 1, 2019, issue of the International Journal of Cardiology.

The study looked at 1,180 people, average age 68, who had at least one previous heart attack or stroke, and recorded their statin use and diet intake at the study's beginning. The researchers identified the people who faithfully followed a Mediterranean-style diet. A Mediterranean-style diet involves consuming medium to high amounts of whole fruits and vegetables, whole grains, legumes and nuts, olive oil, and poultry and fish, with limited amounts of red meat, alcohol, and dairy.

Research we're watching

Want to reduce your risk of cardiovascular disease, diabetes, and colorectal cancer? Eat more fiber, says a meta-analysis published online January 10 by The Lancet.

Authors reviewed data from 185 prospective studies and 58 clinical trials and found that people who ate the most fiber had a 15% to 30% lower risk of dying from cardiovascular disease or developing diabetes or colon cancer, compared with people in the study who ate the least. People appeared to get the biggest benefit when they ate between 25g and 29 g of fiber a day.

Whether you walk or run, participating in a local 5K race can be a good way to enhance your heart health and community spirit.

If you're looking for inspiration to get in shape and strengthen your heart, you might think about doing a couch-to-5K program. These free or low-cost coaching plans (available online or as apps or podcasts) are designed to help would-be runners train for a 5-kilometer race, which is about 3.1 miles. They typically feature timed walking and running intervals that gradually phase out the walking over a period of about nine weeks.

"The purpose of a couch-to-5K program is to give you time to acclimate and start to enjoy the benefits of running and the sense of accomplishment of completing a distance safely," says Dr. Adam Tenforde, director of the Running Medicine Program at the Harvard-affiliated Spaulding Rehabilitation Network. Running provides many cardiovascular benefits as well as an enhanced sense of well-being, he adds.

Olive oil is just one of many plant-based oils rich in unsaturated fats, the more healthful type of fat.

When you're cooking or baking, choose a fat that's liquid instead of solid at room temperature. That advice, from the federal Dietary Guidelines for Americans, is based on a large body of evidence showing that replacing solid fat (mainly saturated fat) with liquid fat (mostly unsaturated fat) is linked to a lower risk of heart attack and death from heart disease.

To be clear, all fat — whether it comes from seeds, nuts, meat, milk, olives, or avocados — contains a mixture of different fatty acids, the basic building blocks of fats. However, butter, lard, coconut oil, and palm oil contain mostly saturated fatty acids. Most plant-based oils, on the other hand, consist predominantly of unsaturated fatty acids, which include both monounsaturated and polyunsaturated fatty acids (see "The fats of life: Healthy oils").

Why do heart attack rates rise on Monday mornings and the week after daylight savings time begins?

Deep inside your brain is a small cluster of cells that serves as your body's master clock. These cells govern your circadian rhythm, the 24-hour internal clock that keeps your body in sync with the day-night cycle. But nearly all your cells also have their own clocks to ensure that each one performs its unique role — such as producing proteins or releasing hormones — at the right time.

These biological timekeepers are under genetic control. But what happens if our behavior or environment is out of sync with our internal clocks? Understanding the potential health consequences of that misalignment is the focus of the Medical Chronobiology Program at Harvard-affiliated Brigham and Women's Hospital, says Dr. Frank Scheer, who directs the program.

At 70 years and counting, the Framingham Heart Study continues to help doctors better understand stroke, dementia, and heart disease.

 Image: © BHPix/Getty Images

In 1948, more than 5,200 people living in a town just west of Boston volunteered for what has evolved into the longest running and best-known study of the causes of heart disease. But the multigenerational Framingham Heart Study has also revealed important clues about brain disorders — most notably stroke but also cognitive decline and dementia (see "Framingham's brain health findings").

In the early 1960s, Framingham researchers coined the term "risk factor," which refers to a characteristic or exposure that raises a person's odds of developing a disease. Over the following decades, they uncovered many such factors for heart disease, including cigarette smoking, obesity, lack of physical activity, and high blood pressure. These habits and conditions also turned out to predispose people to stroke and dementia, thereby establishing that what harms the heart is also bad for the brain.