Knowledge Update

New York, May 7 (IANS) If you are able to steadily maintain a lean body all your life, you are likely to live longer in comparison to those who have since childhood a heavy body that has got heavier during middle age, new research reveals.

The findings showed that people who had a heavy body shape from their childhood and also put on weight during their middle age are at highest risk of mortality with a 15-year risk of death being 19.7 percent in women and 24.1 percent in men.

In contrast, those who remained stably lean throughout life had the lowest mortality, with a 15-year risk of death being 11.8 percent in women, and 20.3 percent in men.

"Our findings provide further scientific rationale for recommendations of weight management, especially avoidance of weight gain in middle life, for long-term health benefit," said Mingyang Song, doctoral student at Harvard University in the US.

In addition, high body mass index (BMI) in adulthood can also increase the mortality risk.

Among the study participants, lowest mortality was found in the BMI range 22-23 among including healthy non-smokers and excluding people with prevalent diseases.

Obesity has become a public health crisis in most countries worldwide. But, these results indicate the importance of weight management across the lifespan, the researchers noted.

For the results, published in The BMJ, the team of researchers tracked the evolution of body shape and associated mortality in two large cohort studies.

Body shape of 80,266 women and 36,622 men were studied at ages 5, 10, 20, 30, and 40 years.

Their body mass indexes were measured at age 50, and were followed from age 60 over a median of 15-16 years for death. 

In a second study, the team carried out a large meta-analysis of 230 prospective studies with more than 3.74 million deaths among more than 30.3 million participants.

They analysed people who never smoked to rule out the effects of smoking, and the lowest mortality was observed in the BMI range 23-24 among this group.

​London, May 4 (IANS) Taking at least 2-3 minutes rest between weight-lifting sets at the gym can help boost muscle growth, British researchers have found.

The results suggest that guys who took longer rest periods showed two-fold increase in myofibrillar protein synthesis (MPS) -- associated with strength and muscle growth.

The study highlights that short rest intervals may actually impair the processes that control muscle growth.

However, with short rests of one minute, the actual muscle response is blunted. 

“If you're looking for maximised muscle growth with your training programme, a slightly longer interval between sets may provide a better chance of having the muscle response you're looking for," said Leigh Breen from University of Birmingham in Britain.

The study, published in the journal Experimental Physiology, analysed 16 men who completed resistance exercises interspersed by either one minute or five minutes of rest. 

Muscle biopsies were obtained at 0, four, 24 and 28 hours post-exercise. 

Beginners starting out on weight training programmes should take sufficient rest, of at least 2-3 minutes, between weight lifting sets that can help with muscle growth, the authors recommended.

For experienced lifters, it's possible that they may not experience the same blunted muscle building response to short rest intervals particularly if they have trained this way for a prolonged period and adapted to this unique metabolic stress. 

"Nonetheless, similar recommendations of 2-3 minutes between sets should help ensure maximal muscle growth in well-trained individuals,” Breen added.​

​New York, May 5 (IANS) Consuming grapes combined with a diet rich in saturated fats can lower obesity risk as well as improve gut bacteria, a new study has found.

According to researchers, it may also help counter the negative effects of a high fat diet, including heart disease, hypertension and diabetes.

The findings showed that the unique and diverse composition of antioxidants called polyphenols present in grapes can help reduce the percentage of body fat, subcutaneous and visceral fat deposits, markers of inflammation in the liver and improve glucose tolerance.

Further, it also increased microbial diversity and decreased abundance of several deleterious bacteria in the intestinal tract.

The research, published in the Journal of Nutritional Biochemistry, is based on two laboratory studies.

In the first study, intake of a diet high in fat content (33 percent of energy from fat) and enriched with 3 percent grapes for 11 weeks, showed a lower percentage of overall body fat and reduced subcutaneous fat deposits.

In the second study, which ran for 16 weeks, the researchers used an even higher fat diet (44 percent of energy from fat) with multiple types of saturated fat, including lard, beef tallow, shortening, and butter similar to some Western-type diets.

"These two studies suggest that grapes and grape polyphenols may help offset a number of the adverse effects of consuming a high fat diet and trigger improvements in intestinal or systemic health," said lead researcher Michael McIntosh from the University of North Carolina in the US.

The researchers investigated the impact of the high fat diet enriched with extracts of either the polyphenol fraction of grapes or the non-polyphenol portion of grapes, as well as the high fat diet plus five percent whole grapes.

All the high fat experimental diets were matched for sugar type and amount.​

​New York, May 4 (IANS) Overturning a common perception that herbs are safe because they have been used for many years, researchers have warned that long-term use of herbal remedies is no guarantee of their safety as many herbs may contain toxic or carcinogenic substances.

In a commentary published in the journal EMBO reports, researchers from Baylor College of Medicine and Stony Brook University discussed scientific evidence showing that the plant Aristolochia can cause aristolochic acid nephropathy (AAN). 

People with this condition experience interstitial nephritis, renal failure and cancers of the urinary track.

In Taiwan, according to the national prescription database, between 1997 and 2003, eight million people were exposed to herbal products containing Aristolochia, the authors remarked.

Studies of patients with renal failure and cancer in Taiwan and China show that tens of millions of people in those countries are at risk of AAN.

In genetically susceptible people, consuming Aristolochia can lead to the formation of complexes between aristolactam, a compound in Aristolachia, and DNA in renal tissues. 

These complexes lead to mutations in the TP53 tumour suppressor gene, which in turn initiate the process toward kidney cancer. Additional studies have shown that this process may also lead to the development of cancer in the liver and the bladder, researchers Donald Marcus, professor emeritus at Baylor and Arthur Grollman, distinguished professor of pharmacological sciences at Stony Brook University, explained.

Although Aristolochia has been used as a herbal remedy for more than 2,000 years, "the intrinsic toxicities were not recognised, owing, in large part, to the latency period between exposure and the onset of symptomatic disease, and, in part, to genetic determinants that confer susceptibility to only approximately five percent of those exposed to this herb", said the authors. 

The long-term scientific study of AAN revealed the association of the disease with Aristolochia.

"The history of Aristolachia indicates that other herbs that have been used for a long time may also have toxic and/or carcinogenic compounds," said the authors.

"It is prudent to assume that many herbs may contain toxic or carcinogenic substances that can cause subsequent health problems for humans," they noted.

Other herbal products and traditional medicines are responsible for severe adverse events in Africa and Asia, but in these cases epidemiological data are lacking, said the researchers suggesting that herbal remedies may be an overlooked global health hazard.​

​London, May 1 (IANS) Listening to traffic reports on the radio could be so dangerous for your driving that you could even miss an elephant standing by the side of the road, warns a study.

"Anything that draws our attention away from driving can be problematic, even if it's auditory like listening to the radio or having a hands-free phone conversation," said one of the researchers Gillian Murphy of University College Cork in Ireland.

The researcher applied a prominent theory of attention, Perceptual Load Theory, to driving, a task where attention is crucial.

Perceptual Load Theory states that we have a finite amount of attention and that once that capacity is maxed out, we cannot process anything else.

To test whether paying attention to radio traffic reports can be bad for our driving, Murphy asked 36 people to drive a route in a full-sized driving simulator while listening to a traffic update on the radio.

While driving, 18 participants were asked to complete a simple task and 18 to complete a complex task. The simple task was to listen for when the voice giving the update changed gender. The complex task was to listen for news of a particular road.

The study found that only 23 percent of the drivers undertaking the complex task noticed a large, unexpected visual stimulus -- an elephant or gorilla by the side of the road.

By contrast, 71 percent of the drivers undertaking the simpler task noticed it.

Drivers undertaking the complex task were also worse at obeying road signs, remembering which vehicle had just passed them and even at driving itself. Their speed, lane position and reaction times to hazards were all affected.

The findings were presented at the British Psychological Society's annual conference in Nottingham in Britain.

"Road safety campaigns are so focused on telling us to keep our eyes on the road, and this is certainly important, but this research tells us that it's simply not enough. We should focus on keeping our brains on the road," Murphy said​

London, April 29 (IANS) Fancy eating chocolates every day? You may soon have the recommendation of doctors to indulge a little as researchers have found that a dark chocolate bar daily could reduces the risk of developing diabetes and heart diseases.

For the study, the researchers analysed data of 1,153 people aged 18-69 years old who were part of the Observation of Cardiovascular Risk in Luxembourg study.

It was found that those who ate 100 g of chocolate a day -- equivalent to a bar -- had reduced insulin resistance and improved liver enzymes. 

Insulin sensitivity is a well-established risk factor to cardiovascular disease.

The findings were published in the British Journal of Nutrition.

The analysis took into account lifestyle and dietary factors, including the simultaneous consumption of tea and coffee. 

This is because both drinks can be high in polyphenol, the substance which may provide chocolate with its beneficial cardiometabolic effects.

"Given the growing body of evidence, including our own study, cocoa-based products may represent an additional dietary recommendation to improve cardio-metabolic health; however, observational results need to be supported by robust trial evidence," said Saverio Stranges, visiting academic at the University of Warwick Medical School in England.

"Potential applications of this knowledge include recommendations by healthcare professionals to encourage individuals to consume a wide range of phytochemical-rich foods, which can include dark chocolate in moderate amounts," Stranges said.

However, it is important to differentiate between the natural product cocoa and the processed product chocolate, which is an energy-dense food. 

Therefore, physical activity, diet and other lifestyle factors must be carefully balanced to avoid detrimental weight gain over time, the researchers warned.​

​London, April 29 (IANS) If you get cravings for chips, sweets and fast-food whenever you are bored, do not blame the situation alone. According to British researchers, people eat more to boost low levels of brain chemical dopamine as they cannot alleviate the boredom in any other way.

The results showed that people were more likely to express a preference for unhealthy foods like crisps, sweets and fast food after completing the boring task.

"This strengthens the theory that boredom is related to low levels of the stimulating brain chemical dopamine and people try to boost this by eating fat and sugar if they cannot alleviate their boredom in some other way," said Dr Sandi Mann from the University of Central Lancashire (UCLan).

Mann and colleagues Faye Ibbitson and Ben Edwards conducted two studies of boredom and food choices.

In the first study, the team asked 52 participants to complete a questionnaire on their food preferences before and after completing the boredom-inducing task of repeatedly copying the same group of letters.

In the second study, they asked 45 participants to watch either a boring or a funny video, during which a range of healthy and unhealthy snacks were available.

They found that the participants who had watched the boring video ate significantly more unhealthy food.

"Health education campaigns can encourage us to make healthier food choices need to take boredom, including boredom in the workplace, into account. Bored people do not eat nuts," Mann stated.

The study was scheduled to be presented at the annual conference of the British Psychological Society this week.​

New York, April 29 (IANS) Retweeting or sharing information on the micro-blogging site can actually make things worse for you as it creates a “cognitive overload” that interferes with learning and retaining what you've just seen, researchers report.

According to the team from Cornell University in the US, that “overload” can spill over and diminish performance in the real world."Most people don't post original ideas any more. You just share what you read with your friends," said Qi Wang, professor of human development at Cornell.“But they don't realise that sharing has a downside. It may interfere with other things we do,” he warned.

Wang and colleagues in China conducted experiments showing that "retweeting" interfered with learning and memory, both online and off.The experiments were conducted at Beijing University, with a group of Chinese college students as subjects.At computers in a laboratory setting, two groups were presented with a series of messages from Weibo - the Chinese equivalent of Twitter.

After reading each message, members of one group had options either to repost or go on to the next message. The other group was given only the "next" option.After finishing a series of messages, the students were given an online test on the content of those messages.Those in the repost group offered almost twice as many wrong answers and often demonstrated poor comprehension.What they did remember they often remembered poorly, Wang reported. "For things that they reposted, they remembered especially worse," she added.

The researchers found that reposters were suffering from "cognitive overload."“When there is a choice to share or not share, the decision itself consumes cognitive resources,” Wang explained.After viewing a series of Weibo messages, the students were given an unrelated paper test on their comprehension of a “New Scientist” article.

Again, participants in the no-feedback group outperformed the reposters. The results confirmed a higher cognitive drain for the repost group."The sharing leads to cognitive overload, and that interferes with the subsequent task," Wang said.“In real life when students are surfing online and exchanging information and right after that they go to take a test, they may perform worse," she suggested in a paper described in the journal Computers in Human Behavior.The researchers suggest that web interfaces should be designed to promote rather than interfere with cognitive processing."Online design should be simple and task-relevant," Wang noted.​

​London, April 29 (IANS) Serious gamers generally avoid touchscreens because these devices lack physical buttons due to which the key press timing in touchscreen input is unpredictable, a team of Finnish researchers has found.

When timing is made more predictable, performance improves, said the group from Aalto University.

"The common view was that the lack of physical buttons is critical but you also have tactile feedback from the surface of a touchscreen. Another false belief was that touchscreens are slower but that is not the case anymore," said Byungjoo Lee, one of the researchers. 

The team conducted experiments where participants were asked to tap a display when a target would appear. 

The data showed large differences between physical keys and touchscreens in how reliably users could time their presses.

The researchers proposed a new theory explaining that there are three sources of error that make timing very hard with touchscreens.

First, people are not able to keep the finger at a constant distance above the surface. The finger is always moving, and even the slightest movement hampers our ability to time precisely. 

By contrast, when using physical keys, the finger rests on the key, eliminating this source of error.

"Second, when the finger touches the surface, it is hard for the neural system to predict when the input event has been registered. Typically software detects the touch when the finger first touches the display. But users cannot sense this event so it is not predictable for them," the authors explained.

Third, when the event has been registered on the touchscreen, it still needs to be processed in the application and in some cases the time that it takes is longer than in other ones, creating another source of latency.

The new theory implies that users' performance can be improved by making touch events more predictable. 

The paper is scheduled to be presented at the "Conference on Human Factors in Computing Systems 2016" (CHI16 conference) in San Jose, California, in May.​

​London, April 27 (IANS) People need not check their cholesterol levels on an empty stomach, suggests new research involving more than 300,000 individuals from Denmark, Canada and the US.

So far, fasting has been required before cholesterol and triglyceride measurement in all countries except Denmark, where non-fasting blood sampling has been used since 2009, the study pointed out.

Fasting is a problem for many patients, and the latest research shows that cholesterol and triglyceride levels are similar whether you fast or not. 

"This will improve patients compliance to preventive treatment aimed at reducing number of heart attacks and strokes, the main killers in the world," said one of the researchers Borge Nordestgaard from Herlev Hospital, University of Copenhagen.

The research was published in the European Heart Journal.

In Denmark, the use of random, non-fasting cholesterol testing at any time of the day irrespective of food intake has been used successfully since 2009. 

Patients, doctors and laboratories have all benefitted from this simplified procedure. For people at work, children, patients with diabetes and the elderly it is particularly beneficial not to have to fast before blood sampling for cholesterol and triglyceride testing.

This is the first international recommendation that fasting is no longer necessary before cholesterol and triglyceride testing. 

These recommendations represent a joint consensus statement from the European Atherosclerosis Society and European Federation of Clinical Chemistry and Laboratory Medicine involving 21 medical experts from Europe, Australia and the US.

"We hope that non-fasting cholesterol testing will make more patients together with their doctors implement lifestyle changes and if necessary statin treatment to reduce the global burden of cardiovascular disease and premature death," Nordestgaard added.​