November 4, 2011
By David W Freeman
Here’s bad news you might want to take standing up. An ominous new report ties a lack of physical activity – spending too much time sitting on your duff, essentially – to up to 43,000 cases of colon cancer and 49,000 cases of breast cancer each year.
The report – presented Thursday at an annual conference of the American Institute for Cancer Research in Washington, D.C. – has experts urging Americans to make more time for physical activity and to take a one- to two-minute break for every hour of sitting.
Something as simple as walking to a colleague’s office instead of sending an email or going to the kitchen to get a glass of water can make a critical difference, experts say. Just don’t make the mistake of thinking regular workouts can eliminate the cancer risk tied to inactivity.
“A person who gets up in the morning and makes time by spending 30 minutes on the treadmill probably feels pretty pleased with himself – and he should,” registered dietitian Alice Bender said in a written statement issued by the institute. But, she asked, “What happens during the other 15 hours and 30 minutes he spends awake? If he’s like most Americans, he sits – on his commute, at the office, and at home.”
Do the math, and that means such a person is physically active for just 3 percent of his time awake.
August 16th, 2011
By: S.L. Baker
Imagine a Big Pharma prescription that will slash your risk of dying by 14 percent and give you at least an extra three years of life. How much you would be willing to pay for it? Many people would find a way to take this disease-preventing pill, no matter what the cost. Although there is no such drug, there is a free non-chemical prescription that can provide you with the amazing health benefits described above. There’s just one catch: you have to take responsibility for your health and get moving for 15 minutes a day.
That’s the dramatic conclusion of a study just published in the online version of The Lancet . Dr. Chi-Pang Wen of the National Health Research Institutes in Taiwan and China Medical University Hospital, and Dr. Jackson Pui Man Wai of the National Taiwan Sport University, headed a research team that investigated a large range of physical activity levels to see just how much exercise produces important health benefits. Previous research has come up with unclear results about whether exercising less than 150 minutes a week can help you live longer.
The new study involved over 400,000 Taiwanese people who participated in standard medical screening in Taiwan between 1996 and 2008, with an average follow-up of 8 years. Based on how much the research subjects said they exercised each week, the study participants were placed into one of five categories of exercise: virtually no exercise (inactive), or low, medium, high, or very high physical activity. Next, the scientists calculated hazard ratios (HR), a statistical measurement used to figure out the odds of an event occurring within a group at a particular time, to see what the risk of death was for every group that was active compared with the inactive group. Then the research team calculated life expectancy for each research participant group.
The results? Compared with individuals in the inactive group, those who were active had dramatic health benefits. Even the research participants in the low activity group who only exercised for an average of 92 minutes per week (about 15 minutes a day) had a 14 percent reduced risk of all-cause mortality, a 10 percent reduced risk of dying from any type of cancer and, on average, a three year longer life expectancy.
What’s more, every additional 15 minutes of exercise each day beyond the minimum amount reduced death from all causes by another four percent and reduced death from cancer by another by one percent. These benefits were found across all age groups and among both men and women. The benefits were even applicable to the people with risks for cardiovascular disease. On the other hand, those in the inactive group who had a 17 percent increased risk of mortality compared with individuals in the low exercise group.
“In Taiwan, if inactive individuals engage in low-volume daily exercise, one in six deaths from all causes could be prevented,” the scientists said in a statement to the media. “If the minimum amount of exercise we suggest is adhered to, mortality from heart disease, diabetes, and cancer could be reduced. This low volume of physical activity could play a central part in the global war against non-communicable diseases, reducing medical costs and health disparities.”
In commentary about the study, Dr. Anil Nigam and Dr. Martin Juneau of the Montreal Heart Institute and Universite de Montreal in Quebec, Canada stated: “The knowledge that as little as 15 minutes per day of exercise on most days of the week can substantially reduce an individual’s risk of dying could encourage many more individuals to incorporate a small amount of physical activity into their busy lives. Governments and health professionals both have major roles to play to spread this good news story and convince people of the importance of being at least minimally active.”
August 2nd, 2011
By: Ryan Jaslow
A little exercise can do a lot for your heart. That’s the message from Harvard researchers after a new study showed that as little as 2.5 hours of exercise a week can dramatically cut heart disease risk.
The U.S. Department of Health and Human Service recommends 2 hours 30 minutes of exercise per week. Researchers looked at 33 studies on exercise’s benefits to see if working out for that amount of time reduced heart disease risk for the study published in the August 1 issue of Circulation. Their analysis found that 2 hours 30 minutes of exercise cut heart disease risk by 14 percent. Even people who exercised less than the recommended time allotment decreased their risk more than those that did nothing.
“The overall findings of the study corroborate federal guidelines – even a little bit of exercise is good, but more is better,” Dr. Jacob Sattelmair, an epidemiologist at the Harvard School of Public Health, said in a written statement.
How much better? Exercising for 300 minutes a week decreased heart disease risk by 20 percent, 750 minutes cut the risk by 25 percent. The protective benefit was found to be even greater for women.
The authors say this is the first study to quantify how much exercise is needed to cut heart disease risk.
“The biggest bang for your buck is at the lower ends of physical activity,” Sattelmair told HealthDay. “If you went from none to 2.5 hours a week, the relative benefit is more than if you went from, say, 5 to 7.5 hours a week.
Heart disease is the number one killer in the U.S. taking more than 631,000 lives each year -one in four deaths. It’s caused by plaque buildup in the coronary arteries which impedes blood flow, resulting in a potentially deadly heart attack.
Besides exercise, maintaining a healthy weight, eating a low-salt diet that’s rich in fruits and vegetables, and not smoking are ways to reduce heart disease risk.
February 4th, 2011
By: Agence France-Presse
The more mothers work during their children’s lifetimes, the more likely their kids are to be overweight or obese, according to a US study published on Friday.
Researchers from American University in Washington, Cornell University in New York state and the University of Chicago studied data on more than 900 elementary- and middle-school-aged children in 10 US cities.
They found that the total number of years the children’s mothers worked had a cumulative influence on their children’s body mass index (BMI) — the weight to height ratio used to measure if a person is overweight or obese.
“Every period of time (averaging 5.3 months) a mother was employed was associated with an increase in her child?s BMI of 10 percent of a standard deviation,” says the study which was published in the journal Child Development.
“For a child of average height, this is equivalent to a gain in weight of nearly one pound (half a kilogram) every five months above and beyond what would typically be gained as a child ages.”
The findings were strongest among sixth graders, the oldest children for whom data was studied. Sixth graders are typically 11 years old.
Changes in the children’s physical activity, time spent unsupervised or watching television did not explain the link between maternal employment and children’s BMI, the study says.
Moreover, a mother working odd hours or overnight was not significantly associated with their children’s BMI.
The researchers were unable to clearly explain the findings but theorized that because working mothers have little time to shop for healthy food and prepare meals, they and their children eat more fast- and packaged foods, which tend to be high in fat and calories.
Childhood obesity in the United States has tripled in 30 years.
Today, one in three US kids is overweight or obese, meaning they are more likely than their normal-weight counterparts to grow up to be obese adults and suffer from obesity-related conditions including diabetes, cardiovascular disease and fatty liver disease.
Childhood obesity has also been linked to “behavior and academic problems in adolescence and adulthood,” said the lead author of the study Taryn Morrissey, assistant professor in public administration and policy at American University, calling for healthy foods to be made more accessible to working families.
“Given that more than 70 percent of US mothers with young children work, the importance of providing support to these families is clear,” the study says.
May 5, 2010
by Rebecca Smith
They discovered that people who slept for less than six hours each night were 12 per cent more likely to die prematurely – before the age of 65 – than those who slept the recommended six to eight hours a night.
The team from the University of Warwick and Federico II University Medical School in Naples analysed 16 studies involving a total of 1.3 million people before reaching their conclusions.
They pointed out that previous studies had shown that sleep deprivation was associated with heart disease, high blood pressure, obesity, type 2 diabetes, and high cholesterol.
However, the researchers also found that sleeping too much was linked to an early death.
Those who slept for more than nine hours a night were 30 per cent more likely to die early, the research published in the journal Sleep found.
That directly contradicts research published in the same journal last week which suggested that people who slept for ten hours or longer a night were more likely to live to 100.
This was thought to be because people who lived into extreme old age were healthier and therefore slept better.
However, the authors of the latest research contradicted this and suggested that long sleep was a sign of underlying illnesses such as depression and low levels of physical activity. Some cancer is also associated with sleeping for longer.
Professor Francesco Cappuccio, leader of the Sleep, Health and Society Programme at the University of Warwick and Consultant Physician at the University Hospitals Coventry and Warwickshire NHS Trust, said: “Whilst short sleep may represent a cause of ill-health, long sleep is believed to represent more an indicator of ill-health.
“Modern society has seen a gradual reduction in the average amount of sleep people take, and this pattern is more common among full-time workers, suggesting that it may be due to societal pressures for longer working hours and more shift-work. On the other hand, the deterioration of our health status is often accompanied by an extension of our sleeping time.
“Consistently sleeping six to eight hours per night may be optimal for health. The duration of sleep should be regarded as an additional behavioural risk factor, or risk marker, influenced by the environment and possibly amenable to change through both education and counselling as well as through measures of public health aimed at favourable modifications of the physical and working environments.”
April 21, 2010
By Julie Steenhuysen
A variant of an obesity gene carried by more than a third of the U.S. population also reduces brain volume, raising carriers’ risk of Alzheimer’s disease, U.S. researchers said on Monday.
People with a specific variant of the fat mass and obesity gene, or FTO gene, have brain deficits that could make them more vulnerable to the mind-robbing disease.
“The basic result is that this very prevalent gene not only adds an inch to your waistline, but makes your brain look 16 years older,” said Paul Thompson, a professor of neurology at the University of California Los Angeles, who worked on the study published in Proceedings of the National Academy of Sciences.
Brains generally shrink with age.
The study compared brain scans of more than 200 people and found consistently less tissue in the brains of people who carry the “bad” version of the FTO gene compared to non-carriers.
On average, people with the obesity variant of the FTO gene had 8 percent less tissue in their frontal lobes — sometimes referred to as the brain’s “command center.” They also had 12 percent less tissue in their occipital lobes, which is the part of the brain that processes vision and other perceptions.
Thompson said reduced brain volume raises a person’s risk for Alzheimer’s disease by reducing the amount of brain reserve a person has to compensate if the brain plaques linked to Alzheimer’s form. Stroke can also reduce brain tissue, depleting the brain’s reserve.
DIET AND EXERCISE
The added brain risk means it is more important for people who carry the FTO gene to eat a low-fat diet and exercise regularly, he said.
A 2008 study of Amish people who had the FTO risk gene but were physically active found they weighed about the same as non-carriers, suggesting that physical activity can overcome a genetic predisposition to obesity.
People with two copies of the FTO gene variant on average weigh nearly 7 pounds (3 kg) more and are about 70 percent more likely to be obese than those who do not have the gene.
“In all the maelstrom of activities you do, exercise and a low-fat diet are genuinely saving your brain from both stroke and Alzheimer’s,” Thompson said.
For the study, Thompson’s team compared magnetic resonance images taken of the brains of 206 healthy people between age 55 and 90 at 58 centers. The centers were taking part in the five-year Alzheimer’s Disease Neuroimaging Initiative, which is examining the factors that help aging brains resist disease.
Because so many people carry the obesity version of the FTO gene, Thompson said the findings may drive research into new drug compounds to alter the effects on the brain.
Short of that, he said the findings should lead carriers to eat less and exercise more.
There is no cure for Alzheimer’s disease, the most common form of dementia affecting 26 million people globally.
Current treatments help with some symptoms, but cannot reverse the course of the disease, leading many scientific teams to look for ways to prevent it.
April 15, 2010
Working out for 20 minutes a day using interval exercise may provide many of the same benefits of much longer workouts done in conventional “long-duration” style.
Many experts “recommend that children and teenagers exercise one hour every day and adults get a weekly minimum of two hours and 30 minutes of moderate intensity physical activity.”
“This could be activities such as brisk walking, dancing, gardening) or one hour and 15 minutes of vigorous activity (jogging, aerobic dancing and jumping rope,” CNN reported.
However, a new study in the Journal of Physiology found that about 20 minutes of high-interval training provided the same benefits of longer exercise sessions that focused on endurance training.
As CNN reported, “The study suggested that quick, high-interval training may represent an alternative to endurance training to improve metabolic health and reduce the risk for chronic diseases.”
April 7, 2010
By Catherine Donaldson-Evans
Looks like Prozac has some competition.
Researchers at Southern Methodist University in Dallas and Boston University are calling exercise a “magic drug” for depression and anxiety.
It has long been known that working out boosts the production of serotonin and other happiness hormones, which are in short supply in the brains of depressed people. But the SMU report, which examined the results of numerous other studies, found that the effects of physical activity on depression are even more powerful than had previously been believed.
Researchers recommended that mental health care providers prescribe exercise as a supplement to the usual treatments including therapy and prescription drugs.
“Exercise has been shown to have tremendous benefits for mental health,” study co-author Jasper Smits, director of the Anxiety Research and Treatment Program at SMU, said in a press release. “The more therapists who are trained in exercise therapy, the better off patients will be.”
Smits and Boston University psychology professor Michael Otto based their findings on the analysis of dozens of clinical and population studies on the links between mental health and exercise and the reduction of anxiety using physical activity.
They characterized exercise as a “magic drug” because its effects resemble those of medicines prescribed for depression.
“It seems like it can do something similar to what the antidepressants can do for depression,” Smits told AOL Health. He said exercise works well as a supplement to psychotherapy and medication for those with severe depression — and can even be used as the sole remedy for those with milder symptoms.
Patients who were down or anxious had fewer symptoms and less stress and anger after working out, according to Smits.
“Exercise appears to affect, like an antidepressant, particular neurotransmitter systems in the brain, and it helps patients with depression re-establish positive behaviors,” he said in the press release. “For patients with anxiety disorders, exercise reduces their fears of fear and related bodily sensations such as a racing heart and rapid breathing.”
But one psychiatrist said that while exercise is undoubtedly a mood lifter, calling it a “magic drug” is a stretch.
“I don’t believe there are any magic cures in psychiatry or mental health,” Daniel Carlat, M.D., who practices in Newburyport, Massachusetts, told AOL Health. “I would be astonished if exercise were a magic drug for depression and anxiety. That sounds to me like an exaggeration.”
But Carlat does believe that the researchers have pinpointed an important trend.
“It is the rare psychiatrist in the United States who actually prescribes (exercise for depression),” he said. “The study is hitting on an interesting fact: Psychiatrists are very focused on medications as the solution to most problems. We don’t think about exercise as we’re giving advice to patients as much as we should.”
Among the many benefits of exercise, Smits said, is its accessibility compared to more common remedies for depression like medication and psychotherapy.
“Exercise can fill the gap for people who can’t receive traditional therapies because of cost or lack of access, or who don’t want to because of the perceived social stigma associated with these treatments,” he said. “Exercise also can supplement traditional treatments, helping patients become more focused and engaged.”
Smits said exercise works much like an antidepressant drug, with patients who are down or anxious reporting fewer symptoms and less stress and anger.
“Exercise appears to affect, like an antidepressant, particular neurotransmitter systems in the brain, and it helps patients with depression re-establish positive behaviors,” he said. “For patients with anxiety disorders, exercise reduces their fears of fear and related bodily sensations such as a racing heart and rapid breathing.”
The advice is especially timely because an estimated 40 percent of Americans lead sedentary lifestyles, according to Smits.
Public health recommendations call for 150 minutes a week of moderate activity or 75 minutes a week of vigorous activity. But therapists would be wise to emphasize the instant benefits of exercise to their patients rather than suggesting any long-term regimen, Smits suggested.
“After just 25 minutes, your mood improves, you are less stressed, you have more energy — and you’ll be motivated to exercise again tomorrow,” he said. “A bad mood is no longer a barrier to exercise; it is the very reason to exercise. This isn’t about working out five times a week for the next year. It’s about exercising for 20 or 30 minutes and feeling better today.”
Smits and Otto presented their findings March 6 at the Anxiety Disorder Association of America’s annual conference.
“It’s exciting,” Smits told AOL Health of the research. “If you’re helping people with a number of different problems, then exercise is a really nice fit.”
January 26, 2010
by Alice Parker
We all know that exercise is good for you. Staying physically active helps keep your heart healthy and your muscles strong, and in cancer patients it has even been shown to ward off relapse. Now a series of independently conducted studies on the effects of exercise in healthy older adults, published on Monday in the Archives of Internal Medicine, confirms that logging time at the gym not only helps maintain good health but may even prevent the onset of chronic diseases, such as heart disease, osteoarthritis and dementia.
In one surprising trial, researchers led by Dr. Teresa Liu-Ambrose at the University of British Columbia randomly assigned 155 aging women to three separate groups and directly compared the cognitive effects of two types of exercise: resistance training, done once or twice weekly, in which participants worked out with free weights and weight machines and did squats and lunges, versus toning and balance exercises, which participants did twice a week.
By the end of the yearlong study, the women who weight-trained saw an improvement in their performance on cognitive tests of memory and learning as well as in executive functions such as decision-making and conflict resolution — women who trained once a week improved their scores in executive functioning by 12.6% — while those who did balance and toning exercises showed no such improvement. The muscle-strengthening exercise also helped the volunteers, ages 65 to 75, boost their walking speed, a commonly used indicator of overall health status in the elderly, as faster pace has been linked with lower mortality.
The Canadian researchers’ findings were somewhat unexpected, given that previous studies on the issue have typically focused on aerobic exercise, which experts believe enhances cognitive function by promoting blood flow to the brain. Liu-Ambrose says her team speculated that anaerobic weight training would have a similar effect for other reasons. First, a resistance-training regimen requires a considerable amount of learning, especially for elderly people who may not be accustomed to the equipment. To learn how to use dumbbells, a leg press or a latissimus pull-down machine correctly, for example, the volunteers were required to focus on the task at hand, master new techniques and retain new information about proper and safe use of equipment. Previous studies have shown that such learning can help older adults maintain mental acuity.
The women also had to remember their weight settings and adjustments to the seats and keep track of the number of repetitions they completed, says Liu-Ambrose. “There is a lot more learning involved that may not occur if you take up a walking program,” she says, noting that it took the volunteers a good two months to get comfortable with the equipment and the training regimen.
In addition, Liu-Ambrose says, other studies have found that people who weight-train show an increase in blood levels of a growth factor that is important for maintaining skeletal mass. This factor, it turns out, also promotes nerve growth, which could be another way that resistance training boosts mental function.
In a second brain-function study, published in the same journal, scientists in Germany found that increased physical activity was associated with a lower incidence of dementia. In this study, researchers recruited 3,485 elderly residents in Bavaria and asked them about their physical activity. None of the participants had dementia at the start of the analysis, but after two years of follow-up, researchers found that those who exercised at least three times a week were half as likely to have developed dementia, compared with the people who reported no physical activity. Based on his results, says lead author Dr. Thorleif Etgen, a professor of psychiatry and psychotherapy at München University, “it doesn’t make a big difference if you have moderate or high physical activity. The important message is that you do any activity. And even if you start late in life, at 60 or 70, there is a benefit, for it’s never too late to start exercising.”
The key words are “moderate or high,” according to another study that was published on Monday in the Archives. Dr. Qi Sun, a researcher at Harvard School of Public Health, analyzed 13,000 women participating in the Nurses’ Health Study and found that when it came to exercise, more was better. Compared with women who jogged for 20 minutes a week, those who jogged three hours a week or walked briskly for five hours a week were 76% more likely to age successfully, free of chronic illnesses such as cancer and heart disease, as well as mental and physical impairment.
Sun’s group found that this benefit occurred across all weight divisions, meaning that even among those who were overweight or obese, women who exercised improved their odds of aging without chronic disease. The effects may apply across different age groups as well; the women were at least 60 years old by the time they enrolled in the study, and while Sun was not able to determine how long they had been exercising prior to that, the results suggest that the health benefits are not limited to the young.
That was the same message of the final exercise paper in the journal, by researchers at University of Erlangen-Nuremberg in Germany. In this trial, a group of 246 elderly women were randomly assigned to an 18-month exercise regimen or wellness program. The women participating in the four-times-weekly exercise sessions, which involved aerobics and balance and muscle training, improved their bone mineral density by nearly 2%. The women in the wellness group, which focused on walking, muscle relaxation and breathing skills, had a 0.33% increase in bone density over the same time period. Perhaps more important, participants in the exercise group saw no increase in their risk of experiencing a fracture-causing fall, compared with a 66% higher risk in the control group.
Despite the positive evidence, however, not all researchers are ready to suggest that exercise is a sure-fire prescription against mental decline or chronic disease in healthy people. To make that claim, a large, longer-term, controlled trial would be needed, in which participants are randomly assigned to exercise or not, and are then followed for the development of chronic conditions such as cancer, heart disease or dementia.
January 14, 2010
New York Times
By Pam Belluck
Americans, at least as a group, may have reached their peak of obesity, according to data the Centers for Disease Control and Prevention released Wednesday.
The numbers indicate that obesity rates have remained constant for at least five years among men and for closer to 10 years among women and children — long enough for experts to say the percentage of very overweight people has leveled off.
But the percentages have topped out at very high numbers. Nearly 34 percent of adults are obese, more than double the percentage 30 years ago. The share of obese children tripled during that time, to 17 percent.
“Right now we’ve halted the progress of the obesity epidemic,” said Dr. William H. Dietz, director of the division of nutrition, physical activity and obesity at the disease control centers. “The data are really promising.
“That said, I don’t think we have in place the kind of policy or environmental changes needed to reverse this epidemic just yet.”
Dr. Dietz said the data probably reflected increased awareness of the obesity problem, especially among women, “who buy food, prepare it and see it, and they’re making changes for themselves that they’re also making for their kids.” He also cited a reduction in “less healthful foods” at school.
Some experts, though, were not optimistic that the leveling off was a result of improved eating and exercise habits.
“Until we see rates improving, not just staying the same, we can’t have any confidence that our lifestyle has improved,” said Dr. David Ludwig, director of the Optimal Weight for Life Program at Children’s Hospital Boston.
Dr. Ludwig said the plateau might just suggest that “we’ve reached a biological limit” to how obese people could get. When people eat more, he said, at first they gain weight; then a growing share of the calories go “into maintaining and moving around that excess tissue,” he continued, so that “a population doesn’t keep getting heavier and heavier indefinitely.”
Furthermore, Dr. Ludwig said, “it could be that most of the people who are genetically susceptible, or susceptible for psychological or behavioral reasons, have already become obese.”
The numbers, published in The Journal of the American Medical Association, are based on national surveys that record heights and weights of a representative sample of Americans. People are considered obese if their body mass index — a ratio of height to weight — is 30 or greater. Someone five and a half feet tall is obese at 186 pounds; a six-foot person is obese at 221 pounds.
Even though the data show an overall plateau for obesity rates, they indicate an increase from 1999 to 2008 in the heaviest boys, ages 6 to 19, primarily whites. Experts speculated that heavy children in environments of unhealthy food and physical inactivity might simply be shifting into the top weight categories because their situation had not improved.
African-American adults have the highest obesity rates — 37 percent among men and nearly 50 percent among women. For Hispanic women, the rate is 43 percent. Hispanic and black children have higher rates than non-Hispanic whites.
Federal health officials had set a goal a decade ago that no more than 15 percent of people would be obese in 2010.
“We aren’t near that, and we haven’t moved in that direction,” said Cynthia L. Ogden, an epidemiologist at the National Center for Health Statistics and an author of the reports.
In addition, 68 percent of adults and nearly one-third of children are considered at least overweight, with a body mass index of 25 or higher. For a 5-foot-8 person, that would be 164 pounds.
Dr. Dietz said he hoped the obesity data would follow what happened with smoking rates, which leveled off before declining. But he said obesity was difficult to address because while “tobacco is a single source, obesity is both physical activity and diet.”
Experts like Steven Gortmaker, a Harvard public health professor, said obesity would decline only with new policies, like penalties and incentives to promote healthier foods and exercise.
“If you look at the reversal of the smoking epidemic,” Dr. Gortmaker said, “substantial change didn’t really happen until there were bans on advertising and limits on consumption through things like taxation. We have to make some substantial changes.”