WEDNESDAY, March 3 (HealthDay News) -- Eating plenty of potassium-rich foods such as leafy greens, potatoes and bananas may reduce the risk of stroke and coronary artery disease, according to Italian researchers.

The new analysis was based on 10 studies published between 1966 and 2009 that included almost 280,000 adults. During follow-ups that ranged from five to 19 years, there were over 5,500 strokes and almost 3,100 coronary heart disease events, the investigators found.

Higher potassium intake was associated with a 19 percent lower risk of stroke and an 8 percent lower risk of coronary heart disease. The findings support global recommendations for people to increase their consumption of potassium-rich foods in order to prevent vascular disease, said Dr. Pasquale Strazzullo, of the University of Naples, and colleagues.

Other foods high in potassium include soybeans, apricots, avocados, plain non-fat yogurt, prune juice, and dried beans and peas.

The findings were presented Wednesday at the American Heart Association's Nutrition, Physical Activity and Metabolism conference in San Francisco.

Another study presented at the meeting found that a diet high in raw fruits and vegetables may help protect against stroke.

In that study, the researchers examined the incidence of stroke among more than 20,000 men and women, aged 20 to 65, who were free of cardiovascular disease at the start of the study. During 10 years of follow-up, there were 233 strokes among the participants.

After they adjusted for a number of factors, the researchers found that people with a high intake (more than 262 grams per day) of raw fruits and vegetables were 36 percent less likely to suffer a stroke than those with a low intake (less than 92 grams per day) of raw fruits and vegetables.

However, there was no association between stroke risk and a high intake (more than 233 grams per day) or low intake (less than 113 grams per day) of processed fruits and vegetables, said Linda Oude Griep of Wageningen University, the Netherlands.

More information

The U.S. National Library of Medicine has more about dietary potassium.

TUESDAY, March 2 (HealthDay News) -- Coffee drinkers can take heart from a series of studies presented this week at American Heart Association conferences in San Francisco.

For example, coffee drinkers appear to have a lower risk of hospitalization for abnormal heart rhythms. And there's no indication that having a few cups every day increases the risk of atherosclerosis, the thickening of blood vessel walls that can lead to heart attacks and other problems. What's more, something in coffee other than caffeine might be responsible for a reduced risk of diabetes for women who regularly imbibe java.

Not every report at the AHA's annual conferences on Cardiovascular Disease Epidemiology and Prevention and Nutrition, Physical Activity and Metabolism was totally upbeat for coffee lovers. One report did find a potential link between coffee drinking and high blood pressure, but the effect was described as "modest." And, like the other studies, it came hedged with the caveat that the finding wasn't based on a controlled trial -- the gold standard for assessing risk and benefit -- but from observational studies, which don't exclude all possible factors.

The heart rhythm research looked at the rate at which 130,054 members of the Kaiser Permanente Medical Care Program were hospitalized for heart rhythm disturbances. About 2 percent of them had hospital stays because of such abnormalities, the most common being atrial fibrillation. But the risk was 18 percent lower for those who reported drinking four or more cups of coffee a day, compared to those who didn't drink coffee, said Dr. Arthur Klatsky, a senior consultant in cardiology for the program, who led the study.

"It might be a surprise, because coffee does give some people the jitters," Klatsky said. "And I don't think we're ready to tell people they should drink coffee to prevent heart rhythm problems."

The study didn't offer any reason why coffee might reduce heart rhythm problems, Klatsky said. "It could be that coffee drinkers have better diets or exercise more. We can't say for sure that it might not be related to minor heart rhythm problems that don't require hospitalization."

The bottom line: "Coffee drinkers don't have to quit because they have heart rhythm problems," Klatsky said. "That's about as far as we can go."

Another study that has followed more than 3,000 men and women for 20 years found no association between coffee consumption and atherosclerosis for just about every demographic group -- men and women, blacks and whites, smokers and nonsmokers. Participants in the study included people whose coffee consumption ranged from none to more than four cups a day.

"Based on these data, there does not appear to be any substantial association between coffee drinking and increased or decreased odds of developing atherosclerosis or its progression over time," study leader Jared Reis, an epidemiologist with the U.S. National Heart, Lung, and Blood Institute, said in a prepared statement.

The third study, based on a report from the long-running Women's Health Study, provided a possible explanation for a lower incidence of type 2 diabetes -- the kind that generally develops later in life -- among coffee drinkers. Researchers compared 359 post-menopausal women newly diagnosed with type 2 diabetes and 359 women without the disease. They found that women who drank four or more cups of caffeinated coffee a day had a 56 percent lower risk of developing the condition than those who did not drink coffee.

That reduced risk appears to be due to the effects of caffeine on a protein that binds to sex hormones, said Dr. Atsushi Goto, of the University of California, Los Angeles, who presented the report. But the finding is preliminary and requires further study, Goto added.

The report linking consumption of one to three cups of coffee a day with a slightly increased risk of high blood pressure came from Dr. Liwei Chen, assistant professor of epidemiology at the Louisiana State University School of Public Health, using data from six studies that included more than 172,000 participants.

"Based on our results, long-term coffee drinking might be a risk factor for hypertension, but the effect is very moderate," Chen said. "We definitely need more research and evidence to clarify our findings based on the meta-analysis of published prospective studies. Meanwhile, I think it is important for people to consider lowering their coffee drinking if they are concerned about their blood pressure."

More information

The American Heart Association   has more on caffeine and the heart.

WEDNESDAY, March 3 (HealthDay News) -- People who watch more television in their 20s and 30s are more apt to develop heart disease risk factors by the time they reach their mid-40s than people who spent less time in front of the screen, a new study finds.

And while that's worrisome enough for many, the worse news is that you can't exercise the risk away.

The findings are to be presented Wednesday at the American Heart Association's Joint Conference: Nutrition, Physical Activity and Metabolism, in San Francisco.

"When we took into account physical activity, the negative effects of TV viewing persisted," confirmed Emmanuel Stamatakis, lead author of the paper and a senior research associate at University College London. "A likely explanation is that the harmful effects of prolonged sitting cannot be simply compensated by doing some physical activity. In other words, the mechanisms of action of the harms of sitting are not the opposite of the benefits of exercise."

And there may be another negative twist to staying glued to a screen.

"We also would expect that, to some extent specifically, TV viewing harms through increased caloric intake [of unhealthy foods]. There is some evidence to support such an explanation but our study could not take into account food intake," Stamatakis said.

Dr. Eugene Storozynsky, assistant professor of medicine at the University of Rochester Medical Center, believes the association might come from behaviors other than sitting.

"I suspect it's not so much the TV watching but other behaviors that go along with TV watching -- specifically, were the study subjects eating lots of carbohydrate-rich foods or drinking carbohydrate-rich drinks at the time they're TV watching?" he said.

"It would be interesting to see if there is a similar association with other sedentary lifestyles with the caveat that these individuals are not able to eat or drink all the time," Storozynsky added. "Has anyone done a study on people who spend a lot of time in libraries and just read and then exercise? After all, every elliptical trainer and treadmill in the gym has a TV above it."

The study was also unusual in that it looked at people in post-adolescence and early adulthood, he added, and it also focused on a specific type of sedentary behavior, said Dr. Robert Scott III, assistant professor of internal medicine at Texas A&M Health Science Center College of Medicine and senior staff cardiologist at Scott & White in Temple, Texas.

The researchers looked at the TV watching and exercise habits of more than 5,600 men and women born in Britain in 1958. Initial measurements were taken in 1981, when the participants were 23 years of age, with additional follow-up done when they reached age 44.

The researchers unearthed three factors that, together, explained 57 percent of the risk difference between those who watched more TV and those who watched less.

One had to do with metabolism -- triglycerides, HDL ("good") cholesterol, body mass index, waist circumference and blood pressure -- which explained 28 percent of the variance.

The second was an inflammatory component including levels of (inflammation-linked) C-reactive protein, which explained 16 percent of variance. The third component involved total cholesterol and LDL ("bad") cholesterol, which explained 13 percent of the variance.

The associations remained evident even after adjusting for physical activity, the team found.

"It was still better if they exercised versus not exercising but the more you watched TV, even if you exercised, increased these risk factors," Scott said.

But it still comes back to the same bottom line people have been told before.

"Sitting in front of the TV for long periods of time should be avoided. In the U.K. and U.S., adults watch TV for around three to four hours a day on average," Stamatakis said. "This is simply too much, given that most of us have sedentary jobs, drive or commute by motorized transport and have lots of other opportunities (that we usually do not miss) to sit," he explained.

"Humans are not made to be sitting for the 10 to 11 hours that, on average, we do (and these 10 to 11 hours are in addition to sleeping)," he added. "Our evolution teaches us that our bodies are made to hunt and run away from our predators, not sit in front of a screen. We have completely ignored this side of our nature; therefore, it is not surprising that our bodies accumulate too much fat, get heart disease, cancer and type 2 diabetes. All these are direct consequences of too much sitting and not enough physical activity -- both, not either/or."

More information

There's more on heart disease at the U.S. Centers for Disease Control and Prevention.

MONDAY, March 1 (HealthDay News) -- A new study suggests that routine electrocardiogram testing of young American athletes would save lives and be cost-effective.

The testing isn't routine among athletes in college and high school, apparently because doctors think the benefits -- discovering potentially deadly heart problems -- aren't worth the expense. However, professional athletes are often required to undergo the tests.

"According to our model, ECG together with a history and physical exam is the preferred strategy for screening athletes for underlying heart disease. This would save the most lives at a cost that is generally agreed to be acceptable for the U.S. health-care system," Dr. Matthew Wheeler, a fellow in cardiovascular medicine at Stanford University School of Medicine and first author of the study, said in a statement.

An Italian study found that sudden deaths during competitions in that country fell by 90 percent after routine tests were put into place.

The authors of the new study used statistics from the Italian researchers and then adjusted them to account for variations in the United States.

While it's uncommon for athletes to die from sudden death, several conditions -- including hypertrophic cardiomyopathy (enlarged heart) -- can lead to it. An estimated one in every 500 people has the condition; doctors recommend athletes stop competing if they have it.

The study appears in the March 2 issue of the Annals of Internal Medicine.

More information:

There's more on sudden death in athletes at the Minneapolis Heart Institute Foundation   .