Diet Drinks May be Associated with Strokes Among Post-menopausal Women

Among post-menopausal women, drinking multiple diet drinks daily was associated with an increase in the risk of having a stroke caused by a blocked artery, especially small arteries, according to research published in Stroke, a journal of the American Heart Association.

This is one of the first studies to look at the association between drinking artificially sweetened beverages and the risk of specific types of stroke in a large, racially diverse group of post-menopausal women. While this study identifies an association between diet drinks and stroke, it does not prove cause and effect because it was an observational study based on self-reported information about diet drink consumption.

Compared with women who consumed diet drinks less than once a week or not at all, women who consumed two or more artificially sweetened beverages per day were:

  • 23 percent more likely to have a stroke;
  • 31 percent more likely to have a clot-caused (ischemic) stroke;
  • 29 percent more likely to develop heart disease (fatal or non-fatal heart attack); and
  • 16 percent more likely to die from any cause.

Researchers found risks were higher for certain women. Heavy intake of diet drinks, defined as two or more times daily, more than doubled stroke risk in:

  • women without previous heart disease or diabetes, who were 2.44 times as likely to have a common type of stroke caused by blockage of one of the very small arteries within the brain;
  • obese women without previous heart disease or diabetes, who were 2.03 times as likely to have a clot-caused stroke; and
  • African-American women without previous heart disease or diabetes, who were 3.93 times as likely to have a clot-caused stroke.

“Many well-meaning people, especially those who are overweight or obese, drink low-calorie sweetened drinks to cut calories in their diet. Our research and other observational studies have shown that artificially sweetened beverages may not be harmless and high consumption is associated with a higher risk of stroke and heart disease,” said Yasmin Mossavar-Rahmani, Ph.D., lead author of the study and associate professor of clinical epidemiology and population health at the Albert Einstein College of Medicine in the Bronx, New York.

Researchers analyzed data on 81,714 postmenopausal women (age 50-79 years at the start) participating in the Women’s Health Initiative study that tracked health outcomes for an average of 11.9 years after they enrolled between 1993 and 1998. At their three-year evaluation, the women reported how often in the previous three months they had consumed diet drinks such as low calorie, artificially sweetened colas, sodas and fruit drinks. The data collected did not include information about the specific artificial sweetener the drinks contained.

The results were obtained after adjusting for various stroke risk factors such as age, high blood pressure, and smoking. These results in postmenopausal women may not be generalizable to men or younger women. The study is also limited by having only the women’s self-report of diet drink intake.

“We don’t know specifically what types of artificially sweetened beverages they were consuming, so we don’t know which artificial sweeteners may be harmful and which may be harmless,” Mossavar-Rahmani said.

The American Heart Association recently published a science advisory that found there was inadequate scientific research to conclude that low-calorie sweetened beverages do – or do not – alter risk factors for heart disease and stroke in young children, teens or adults. The Association recognizes diet drinks may help replace high calorie, sugary beverages, but recommends water (plain, carbonated and unsweetened flavored) as the best choice for a no calorie drink.

“Unfortunately, current research simply does not provide enough evidence to distinguish between the effects of different low-calorie sweeteners on heart and brain health. This study adds to the evidence that limiting use of diet beverages is the most prudent thing to do for your health,” said Rachel K. Johnson, Ph.D., R.D., professor of nutrition emeritus, University of Vermont and the chair of the writing group for the American Heart Association’s science advisory, Low-Calorie Sweetened Beverages and Cardiometabolic Health.

“The American Heart Association suggests water as the best choice for a no-calorie beverage. However, for some adults, diet drinks with low calorie sweeteners may be helpful as they transition to adopting water as their primary drink. Since long-term clinical trial data are not available on the effects of low-calorie sweetened drinks and cardiovascular health, given their lack of nutritional value, it may be prudent to limit their prolonged use” said Johnson.

Source: American Heart Association


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With Age Comes Hearing Loss and a Greater Risk of Cognitive Decline

Scott LaFee wrote . . . . . . . . .

Hearing impairment is a common consequence of advancing age. Almost three-quarters of U.S. adults age 70 and older suffer from some degree of hearing loss. One unanswered question has been to what degree hearing impairment intersects with and influences age-related cognitive decline.

In a new study, researchers at University of California San Diego School of Medicine report that hearing impairment is associated with accelerated cognitive decline with age, though the impact of mild hearing loss may be lessened by higher education.

The findings are published in the Journal of Gerontology: Series A Medical Sciences.

A team of scientists, led by senior author Linda K. McEvoy, PhD, professor in the departments of Radiology and Family Medicine and Public Health, tracked 1,164 participants (mean age 73.5 years, 64 percent women) in the longitudinal Rancho Bernardo Study of Healthy Aging for up to 24 years. All had undergone assessments for hearing acuity and cognitive function between the years 1992 to 1996 and had up to five subsequent cognitive assessments at approximately four-year intervals. None used a hearing aid.

The researchers found that almost half of the participants had mild hearing impairment, with 16.8 percent suffering moderate-to-severe hearing loss. Those with more serious hearing impairment showed worse performance at the initial visit on a pair of commonly used cognitive assessment tests: the Mini-Mental State Exam (MMSE) and the Trail-Making Test, Part B. Hearing impairment was associated with greater decline in performance on these tests over time, both for those with mild hearing impairment and those with more severe hearing impairment.

However, the association of mild hearing impairment with rate of cognitive decline was modified by education. Mild hearing impairment was associated with steeper decline among study participants without a college education, but not among those with higher education. Moderate-to-severe hearing impairment was associated with steeper MMSE decline regardless of education level.

“We surmise that higher education may provide sufficient cognitive reserve to counter the effects of mild hearing loss, but not enough to overcome effects of more severe hearing impairment,” said McEvoy.

Degree of social engagement did not affect the association of hearing impairment with cognitive decline. “This was a somewhat unexpected finding” said first author Ali Alattar. “Others have postulated that cognitive deficits related to hearing impairment may arise from social isolation, but in our study, participants who had hearing impairment were as socially engaged as those without hearing loss.”

The findings, said the authors, emphasize the need for physicians to be aware that older patients with hearing impairments are at greater risk for cognitive decline. They also emphasized the importance of preventing hearing loss at all ages, since hearing impairment is rarely reversible. One important way to protect hearing, they said, is to minimize loud noise exposure since this is the largest modifiable risk factor for hearing impairment.

Source: UC San Diego


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New Wisdom about High Cholesterol Treatment for Adults Aged 80 and Older

Experts know that in adults younger than 65, having high cholesterol levels in your blood can raise your risk for heart attacks and strokes. However, in adults 80 years old and older, researchers have not—until now—thoroughly studied high cholesterol’s impact on heart disease, your ability to function well, or your risk for death.

In fact, some research shows that a higher level of total cholesterol and a lower level of so-called “bad” cholesterol (also known as “low-density lipoprotein” or LDL cholesterol) might be helpful in protecting your ability to perform daily activities and preserving your life for longer.

What’s more, it appears that having low cholesterol is linked to a higher risk of death from cancer, respiratory disease, and accidents in adults aged 80 and older. It also appears that the benefits of taking medications known as statins, which lower cholesterol, may lessen as people age. Researchers even have a phrase for this phenomenon. They call it the “risk factor paradox.” This describes the fact that for adults aged 80 and older, having some conditions that are considered health risks in younger adults predicts better survival. These conditions include having higher total cholesterol, higher blood pressure, and higher body mass index (BMI, a ratio of body weight to height that helps determine whether you are overweight or obese).

“Triglycerides” are one type of blood fat that your body uses for energy. High levels of triglycerides can raise risks for heart disease in younger adults. However, we don’t know as much about the risks to adults aged 80 and older, or whether high levels of triglycerides can affect their risks for disability or even death.

A team of researchers in China decided to learn more about whether current triglyceride-level guidelines make sense for people aged 80 and older. To do so, the team explored links between triglyceride levels and the ability to perform daily self-care activities, cognitive function (the ability to think and make decisions), and frailty (a condition associated with aging that increases the risks of poor health, falls, disability, and death. Signs of frailty include weakness, weight loss, and low activity levels.). Researchers also looked at whether triglyceride levels had an impact on death in a group of 930 Chinese adults aged 80 or older.

The researchers learned that for the oldest people in the study, having a higher triglyceride level was linked to a lower risk of cognitive decline, less of a reduction in the ability to perform daily tasks, less frailty, and lower risk for death.

The researchers said their results challenge current thinking that having high triglyceride levels is a risk factor for age-related chronic disorders and death. The researchers said their study suggested that, after the age of 80, taking medication to lower cholesterol may not have much—or any—benefit.

Source: The AGS Foundation for Health in Aging

Fasting Boosts Metabolism and Fights Aging

Tim Newman wrote . . . . . . . . .

The latest study to explore the impact of fasting on the human body concludes that it increases metabolic activity more than previously realized and may even impart anti-aging benefits.

Studies have shown that intermittent fasting can help certain people lose weight.

Although researchers are still debating exactly how effective fasting can be for weight loss, new research hints at other benefits.

In rats, for instance, studies show that fasting can increase lifespan.

Although exciting, evidence of this in humans has yet to be seen.

The most recent study — which the authors have now published in the journal Scientific Reports — takes a fresh look at fasting in humans and provides new insight.

“Recent aging studies have shown that caloric restriction and fasting have a prolonging effect on lifespan in model animals,” says first study author Dr. Takayuki Teruya, “but the detailed mechanism has remained a mystery.”

In particular, scientists at the Okinawa Institute of Science and Technology Graduate University in Japan examined its impact on metabolism.

By understanding the metabolic processes involved, the team hopes to find ways of harnessing the benefits of fasting without the need to go without food for prolonged periods.

To investigate, they fasted four volunteers for 58 hours. Using metabolomics, or the measurement of metabolites, the researchers analyzed whole blood samples at intervals during the fasting period.

What happens during fasting?

As the human body is starved of food, there are a number of distinct metabolic changes that occur.

Normally, when carbohydrates are readily available, the body will use them as fuel. But once they are gone, it looks elsewhere for energy. In a process called gluconeogenesis, the body derives glucose from noncarbohydrate sources, such as amino acids.

Scientists can find evidence of gluconeogenesis by assessing the levels of certain metabolites in the blood, including carnitines, and butyrate.

As expected, after fasting, the levels of these metabolites were present in the participants’ blood. However, the scientists also identified many more metabolic changes, some of which surprised them. For instance, they saw a marked increase in products of the citric acid cycle.

The citric acid cycle happens in mitochondria, and its function is to release stored energy. The hike seen in the metabolites associated with this process means that the mitochondria, the fabled powerhouses of the cell, are thrust into overdrive.

Another surprise finding was an increase in levels of purine and pyrimidine, which scientists had not yet linked to fasting.

These chemicals are a sign of increased protein synthesis and gene expression. This suggests that fasting causes cells to switch up the type and quantity of proteins that they need to function.

Fasting promotes anti-aging compounds

Higher levels of purine and pyrimidine are clues that the body might be increasing levels of certain antioxidants. Indeed, the researchers noted substantial increases in certain antioxidants, including ergothioneine and carnosine.

In an earlier study, the same team of researchers showed that, as we age, a number of metabolites decline. These metabolites include leucine, isoleucine, and ophthalmic acid.

In their latest study, they showed that fasting boosted these three metabolites. They explain that this might help explain how fasting extends lifespan in rats.

In all four subjects, the researchers identified 44 metabolites that increased during fasting, some of which increased 60-fold.

Of these 44, scientists had linked just 14 to fasting before. The authors conclude that “[c]ollectively, fasting appears to provoke a much more metabolically active state than previously realized.”


“These are very important metabolites for maintenance of muscle and antioxidant activity […]. This result suggests the possibility of a rejuvenating effect by fasting, which was not known until now.”

Dr. Takayuki Teruya


The scientists believe that a hike in antioxidants might be a survival response; during starvation, our bodies can experience high levels of oxidative stress. By producing antioxidants, it might help avoid some of the potential damage caused by free radicals.

Next, they want to replicate the results in a larger sample. They also want to identify possible ways of harnessing the beneficial effects of fasting and find out whether they can trigger the effects of caloric restriction without having to restrict caloric intake.

Although it will be some time before we can reap the benefits of fasting without the effort, the current findings provide further evidence of the health benefits of fasting.

Source: Medical News Today

Women’s Brains May Be More ‘Age-Resistant’ Than Men’s

Dennis Thompson wrote . . . . . . . . .

“Boys will be boys” goes the old saying, but girls might have the last laugh.

It turns out that female brains tend to age more slowly, researchers report.

On average, women’s brains appear to be about three years younger than those of men at the same chronological age. This could provide one clue to why women tend to stay mentally sharp longer than men, the authors noted.

“Women tend to score better on cognitive tests than men as they age,” said lead researcher Dr. Manu Goyal, an assistant professor at the Mallinckrodt Institute of Radiology at Washington University School of Medicine in St. Louis. “It’s possible the finding we’re seeing helps to explain some of that.”

Scientists have observed that people’s brains change both in structure and function as they grow older.

One change involves the way the brain uses sugar and oxygen to fuel its efforts, Goyal said.

“The brain really relies on glucose and oxygen to meet its metabolic needs, and it’s a very large consumer of those resources,” Goyal said. “How it uses glucose and oxygen, and in what parts of the brain it uses the most, changes as people typically age.”

Goyal and his colleagues initially set out to see if a computer program could use this brain metabolism pattern to predict someone’s age. The program did pretty well, but it made some mistakes, so the research team set about accounting for those errors.

The researchers recruited 205 people aged 20 to 82 to undergo brain imaging scans that measured the flow of oxygen and sugar within their brains. That data was then fed into the computer program.

“One of the things we looked at was women versus men. When we started looking at that, we were pleasantly surprised that when the machine was trying to age a woman compared to a man, it consistently aged the woman to be a little bit younger than the man,” Goyal said.

“On average, it found that women appeared to be younger than men in terms of their metabolic brain age, in terms of what their brain metabolism pattern looked like,” he said.

The team first trained the algorithm by feeding it men’s ages and brain metabolism, and then fed in female brain metabolism data. Based on the male benchmark, the algorithm judged women’s brains an average of 3.8 years younger than their actual age.

Researchers then tried using a female benchmark set with women’s ages and brain metabolism. Similarly, the algorithm judged men’s brains to be an average 2.4 years older than their actual age.

The relative youthfulness of female brains was detectable even when comparing men and women in their 20s, the researchers said.

“It’s not that women’s brains seem to age slower than men’s,” Goyal said. “Rather, it seems that women’s brains start off at a younger age when they reach adulthood, and they keep that throughout the remainder of their adulthood, basically buying them a few extra years.”

The researchers suspect that women gain this advantage during puberty, Goyal said.

“As females and males go through puberty, how their brain changes is very different,” Goyal said. “Males, their blood flow to the brain decreases quite a bit as they go through puberty. In women, it doesn’t decrease as much. In fact, it might go down and then come back up again. Differences in how a female’s and a male’s brain develops across puberty sets the stage for how they’re going to age subsequently.”

However, Goyal noted that these effects are relatively small, and at this point can’t be used to directly explain different changes in mental acuity that occur during aging.

“Dementia is such a complex process,” Goyal said. “This might mean women are a little bit more resilient to certain aspects of brain aging in general, but it could also introduce certain vulnerabilities. Having a younger brain for longer could make the brain more vulnerable to certain things as well. We’re being very cautious in not speculating on what this means in terms of downstream dementia and so forth.”

In fact, brain metabolism might have little to do with diseases like Alzheimer’s or dementia, said Dr. Gayatri Devi, a neurologist with Lenox Hill Hospital in New York City.

“The typical female brain is more energetically youthful than the typical male brain throughout life. This difference is present even in brains that show amyloid plaques that are seen in Alzheimer’s disease, although none of the persons had any clinical symptoms of the condition,” Devi said of the new findings. She was not part of the study.

“Despite this relative brain youthfulness, however, women are at higher risk for developing Alzheimer’s than men,” Devi continued. “Estrogen, which increases vitality of the brain regions involved in memory, but which plummets after menopause in women, may be a factor, although multiple other factors are likely involved.”

The study appears in Proceedings of the National Academy of Sciences.

Source: HealthDay


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