HappehCom

Feb 152015
 

Scientists_Make_Mistakes-MilkNotSoGoodForPeople

Drinking milk may not protect our bones from fractures – and could even increase a person’s risk of dying from heart disease, according to a major new study in Sweden.

In surprising results, an investigation into dietary habits of more than 100,000 people found those who drank more milk were no less likely to break a bone. Among women, higher milk consumption was actually linked to an increased risk of hip fractures.

Even more strikingly, people who drank more than three glasses of milk – around 680ml – per day, were more likely to die over the course of the study, which tracked 60,000 women for 20 years, and 45,000 men for 11 years.

The effect was most pronounced among women, who were nearly twice as likely to die, with heart disease the condition with the strongest links to higher milk consumption.

Although potentially alarming, the authors of the study from Uppsala University urged caution and said their evidence was not strong enough for dietary recommendations to change.

Women who took part in the study were aged 39-74, and the men 45-79 when the research began, so it is not surprising that significant numbers died over the following two decades. The study was observational, matching people’s self-reported answers to dietary surveys with their medical records, and does not prove cause and effect.

Although the researchers took several confounding factors such as smoking rates, alcohol use and weight into account, commentators said their influence may have been understated.

However, experts from several countries agreed that the results merited further investigation.

“As milk consumption may rise globally with economic development and increasing consumption of animal source foods, the role of milk in mortality needs to be established definitively now,” said Professor Mary Schooling, of City University of New York’s school of public health.

The study is published in the British Medical Journal.

Current dietary guidelines recommend milk and other dairy products as good sources of protein and calcium, which is essential for healthy bones. There is no suggestion in the study that drinking one glass of milk a day is unhealthy. The researchers did not make a distinction between full fat, semi-skimmed or skimmed milk.

Intriguingly, other dairy products including yoghurt and cheese were linked with better bone health and lower mortality risk.

The authors have suggested that the cause of milk’s adverse effect may be galactose, a type of sugar, high levels of which are present in non-fermented milk but not in fermented products. Galactose has been shown to have harmful effects such as inflammation and chemical imbalances in animal studies, but evidence of their role in human health is scant.

Gaynor Bussell, a dietician and public health nutritionist said that the study was interesting but warned that food questionnaires were “not the gold standard” for understanding daily intake.

“We do know that increase in inflammation is associated with reduced bone density and so the effect of galactose certainly needs to be looked at in further studies,” she said.

“Calcium is required in the diet for bone health and we require approximately the daily amount of calcium that’s in about a pint of milk. So milk is a very convenient source of calcium as well as many other vitamins and minerals. Some caution is required here in interpreting the results and so I would urge some more research in this area that can back or refute these findings. One such study is insufficient to base public health decisions on.”

Feb 132015
 

An ingredient in Viagra could cause blindness in both men with eye problems and those with seemingly normal vision, according to a new study.

Science_That_Supports_Happeh_Theory-ViagraCanPermanentlyDamageVision

Sildenafil, the active ingredient in the erectile dysfunction medication, could permanently damage the vision of a man with a hereditary eye condition, but also those who have normal sight and carry one gene linked to the eye problem, Australian researchers said.

Scientists claim that the drug could cause permanent damage to the eyes of people with retinitis pigmentosa – a rare inherited disease which causes the cells in the retina to gradually die.

Suffers can find it difficult to see in dim light, lose their peripheral vision, and can sometimes go blind.

Around one in 50 people carry the genes which can trigger the retinal cell death.
Read more: Cut-price Viagra available on the NHS after price fall
Chinese businessman arrested for secretly adding Viagra to drinks

To make their findings published in the journal ‘Experimental Eye Research’, researchers from the University of New South Wales, Australia, gave a dose of sildenafil to healthy mice and ones with a copy of the mutant gene.

The scientists discovered that the healthy mice experienced problems with their eyes for around two days.

But mice with the gene had eye problems for a fortnight, the Mail Online reported.

The researchers also identified early signs of cell death in the mices’ retinas, indicating that the drug may cause loss of vision in people who carry the gene for the disease but have normal vision.

Dr Lisa Nivison-Smith, of the UNSW School of Optometry and Vision Science, said: “If cells actually die in the retina that would lead to blindness.”

She went on to explain that people who have normal vision, but carry a single copy of the mutant gene for retinitis pigmentosa, could be more susceptible to changes caused by sildenafil.

On its website, the NHS stressed that the study was only conducted on mice and therefore not yet proven in humans, but added that people should stop taking sildenafil citrate and seek immediate medical advice if they suddenly develop eye or eyesight problems.

Feb 132015
 

Hitting the gym can boost your memory, researchers have found.

They say an intense workout of as little as 20 minutes can enhance your long-term memory by 10 percent in healthy young adults.

Although the study used weight exercises, researchers said that resistance activities such as squats or knee bends would probably produce the same results.

Scroll down for video
Minoru Shinohara, an associate professor in the School of Applied Physiology and one of the study’s researchers, watches a student during a resistance exercise. The team found an intense workout of as little as 20 minutes can enhance your long-term memory by 10 percent in healthy young adults.

Minoru Shinohara, an associate professor in the School of Applied Physiology and one of the study’s researchers, watches a student during a resistance exercise. The team found an intense workout of as little as 20 minutes can enhance your long-term memory by 10 percent in healthy young adults.
HOW THEY DID IT

The study began with everyone looking at a series of 90 photos on a computer screen.

The images were evenly split between positive (i.e. kids on a waterslide), negative (mutilated bodies) and neutral (clocks) pictures.

Participants weren’t asked to try and remember the photos.

Everyone then sat at a leg extension resistance exercise machine. Half of them extended and contracted each leg at their personal maximum effort 50 times.

The control group simply sat in the chair and allowed the machine and the experimenter to move their legs.

Throughout the process, each participant’s blood pressure and heart rate were monitored.

Every person also contributed saliva samples so the team could detect levels of neurotransmitter markers linked to stress.

‘Our study indicates that people don’t have to dedicate large amounts of time to give their brain a boost,’ said Lisa Weinberg, the Georgia Tech graduate student who led the project.

Although the study used weight exercises, Weinberg said that resistance activities such as squats or knee bends would probably produce the same results.

Science_That_Supports_Happeh_Theory-ExerciseEnhancesLongTermMemory

The study, which was published in the journal Acta Psychologica, studied participants asked to lift weights just once two days before testing them.

The Georgia Tech researchers also had participants study events just before the exercise rather than after workout.

They did this because of extensive animal research suggesting that the period after learning (or consolidation) is when the arousal or stress caused by exercise is most likely to benefit memory.

The study began with everyone looking at a series of 90 photos on a computer screen.

The images were evenly split between positive (i.e. kids on a waterslide), negative (mutilated bodies) and neutral (clocks) pictures.

Exercise Video

Everyone then sat at a leg extension resistance exercise machine.

Half of them extended and contracted each leg at their personal maximum effort 50 times.

The control group simply sat in the chair and allowed the machine and the experimenter to move their legs.

Throughout the process, each participant’s blood pressure and heart rate were monitored.

Every person also contributed saliva samples so the team could detect levels of neurotransmitter markers linked to stress.

The participants returned to the lab 48 hours later and saw a series of 180 pictures – the 90 originals were mixed in with 90 new photos.

The control group recalled about 50 percent of the photos from the first session.

Although the study used weight exercises, Weinberg said that resistance activities such as squats or knee bends would probably produce the same results.

Although the study used weight exercises, Weinberg said that resistance activities such as squats or knee bends would probably produce the same results.

Those who exercised remembered about 60 percent.

‘Even without doing expensive fMRI scans, our results give us an idea of what areas of the brain might be supporting these exercise-induced memory benefits,’ said Audrey Duarte, an associate professor in the School of Psychology.

‘The findings are encouraging because they are consistent with rodent literature that pinpoints exactly the parts of the brain that play a role in stress-induced memory benefits caused by exercise.’

The collaborative team of psychology and applied physiology faculty and students plans to expand the study in the future, now that the researchers know resistance exercise can enhance episodic memory in healthy young adults.

‘We can now try to determine its applicability to other types of memories and the optimal type and amount of resistance exercise in various populations,’ said Minoru Shinohara, an associate professor in the School of Applied Physiology.

‘This includes older adults and individuals with memory impairment.’

Feb 132015
 

The benefits of going for a run to alleviate stress after a tough day in the office are well known.

Science_That_Supports_Happeh_Theory-ExerciseEliminatesDepressiveChemicals

But a new study has found out why working up a sweat is so relaxing and mood-boosting.

Exercise actually detoxes harmful chemicals from the body and can alleviate depression.

Researchers at the Karolinska Institute in Sweden have discovered that physical activity purges the blood of a substance which accumulates during stress and can be harmful to the brain.

Previous studies have suggested that people feel more positive after exercise because it releases a rush of endorphins.

But it now appears that during exercise, the muscles begin to act like the liver or kidneys and produce an enzyme which clears out a molecule linked to depression.

The team is hopeful that eventually a pill could be produced which would trigger the same effect to help the mentally ill.

“Our initial research hypothesis was that trained muscle would produce a substance with beneficial effects on the brain,” said Dr Jorge Ruas, principal investigator at the Department of Physiology and Pharmacology.

“We actually found the opposite: well-trained muscle produces an enzyme that purges the body of harmful substances. So the muscle’s function is reminiscent of that of the kidney or the liver.”

Dr Ruas said cardiovascular exercise would probably have the biggest impact on mood and reducing stress.

“It is possible that other kinds of exercise will also have an effect, like resistance training such as weight lifting. But our results support the use of aerobic exercise like biking and running.

“Skeletal muscle appears to have a detoxification effect that, when activated, can protect the brain from mental illness.”

The study also demonstrates why people who do not exercise end up feeling sluggish, depressed and are more prone to disease.

GPs can currently prescribe exercise for depression, but are far more likely to prescribe anti-depressants. There were 53?million prescriptions were issued for antidepressants in England alone last year, nearly double the number prescribed a decade ago.

“Our modern, sedentary lifestyles that don’t include sufficient physical activity, might have made us mode susceptible to diseases such as stress-induced depression,” Dr Ruas added.

“Physical exercise is already prescribed as a therapy or co-therapy for mild to moderate depression. We think that our findings will help support the use of physical exercise in the prevention and treatment of depression.”

Researchers had known that the protein PGC-1a1 increases in skeletal muscle during exercise but were unclear about what it was doing.

The team genetically engineered mice to have high levels of the protein and then exposed them, and a control group of normal mice, to a stressful environment of loud noises and flashing lights.

They found that after five weeks the normal mice had become depressed but the engineered mice appeared to be protected.

It is thought that the protein produces an enzyme called KAT which turns the harmful kynurenine molecule into harmless kynurenic acid which can be passed easily out of the body.

Carmine Pariante, Professor of Biological Psychiatry at Kings College London said the finding was ‘very important’ to the understanding of exercise and depression.

“Exercise is always good for mental and physical health,” he said.

“This study shows one of the mechanisms by which exercise is beneficial but is not the only one good thing – people should exercise anyway.”

Dr Clare Stanford, Reader in Experimental Psychopharmacology, UCL, said: “The suggestion that kynurenin is a casual factor in depression is not new, but linking it with muscle metabolism and the beneficial effects of exercise on mood is really interesting. That said, I think the interpretation of the behavioural data should be more cautious.

“Although stress-induced immobility in mice is used as a screen for antidepressant drugs, there is evidence that it is not a mouse version of depression (anti-depression and depression probably target completely brain processes). A reduction in sucrose preference is a more plausible analogue of anhedonia (the inability to experience pleasure), but that is only one aspect of depression and, by itself, would not qualify for a diagnosis of depression in humans.

“In summary, this is interesting research but does not necessarily explain the role of exercise in reducing depression in humans.”

The study was published in the journal Cell.

Feb 132015
 

Common sleeping tablets and anxiety drugs taken by millions of patients has been linked to a 50 per cent increased risk of Alzheimer’s disease, researchers have found.

Scientists_Make_Mistakes-SleepingPillsCauseAlzheimers

Taking the drugs known as benzodiazepines, which include diazepam and lorazepam, for three months or more was linked with a greater chance of being diagnosed with Alzheimer’s disease five years later.

At least six million prescriptions were issued for the drugs in England last year and the researchers said the findings are important because of the large numbers of older people taking the medicines.

Researchers behind the study described the findings as being of “major importance for public health”.

They warned that although it cannot be definitively proven that the drugs are causing Alzheimer’s there is a strong ‘suspicion of possible direct causation’.

The drugs should be not be taken for more than three months in light of these findings, the researchers said.

However, other experts said the results may reflect that people who are already in the early stages of Alzheimer’s are often treated for sleep problems and anxiety and this is confusing the findings.

In a research paper published in the British Medical Journal, scientists from the University of Bordeaux and the Univeristy of Montreal beind the latest study said their findings were especially important “considering the prevalence and chronicity of benzodiazepine use in elderly populations and the high and increasing incidence of dementia in developed countries.”

They said: “It is now crucial to encourage physicians to carefully balance the benefits and risks when initiating or renewing a treatment with benzodiazepines and related products in elderly patients.”

The French and Canadian researchers examined data from Quebec from a period of at least six years and identified 1,796 cases of Alzheimer’s disease which where then individually matched with 7,184 healthy people matched for age, sex, and duration of follow-up.

They found that past use of benzodiazepines was associated with a 51 per cent increased risk fo Alzheimer’s disease. The link was stronger with longer exposure to the drugs or use of long-acting versions of the medicines.

In an accompanying editorial Professor Kristine Yaffe of the University of California at San Francisco and Professor Malaz Boustani of the Indiana University Centre for Aging Research, said that in 2012 the American Geriatrics Society included benzodiazepines in a list of drugs that should not be used in older people because of the side effects of brain function.

Dr Liz Coulthard, Consultant Senior Lecturer in Dementia Neurology at University of Bristol, said: “This work provides yet another reason to avoid prescription of benzodiazepines for anything other than very short term relief of insomnia or anxiety.

“In addition to short term cognitive impairment, falls and car accidents already known to be associated with benzodiazepine use, there is a hint from this study that these drugs might in some way increase the risk of developing Alzheimer’s disease.

“However, we know that Alzheimer’s disease pathology accumulates for up to 17 years prior to diagnosis and this study looked at benzodiazepine use well into the course of the pathological cascade in the disease.

“In addition, retrospective studies such as this cannot prove causation. Therefore there is still a possibility that, rather than causing Alzheimer’s disease, benzodiazepines tend to be prescribed to patients presenting with anxiety or insomnia as part of an as yet undiagnosed dementia.”

Prof Gordon Wilcock, Emeritus Professor of Geratology at University of Oxford, said: “This carefully conducted study provides convincing evidence that the use of benzodiazepines may contribute to the development of Alzheimer’s disease, and importantly may be another factor we could modify to reduce the occurrence of dementia.

“However, these drugs would have been given to treat symptoms and it is possible that the latter may have been the earliest signs of unrecognised Alzheimer’s disease, although the authors have tried to control for this as far as was possible in their study.

“Ideally more research needs to be undertaken, but it will be difficult to do this prospectively as most clinicians would avoid long term prescription of these drugs in older people.”

Dr James Pickett, head of research at Alzheimer’s Society, said: “With 1.5million people in the UK being prescribed benzodiazepines at any one time, evidence that their long-term use increases the risk of dementia is significant, and raises questions about their use.

“This research should not be used to condemn benzodiazepines completely, since their short-term use can have an important role in the management of anxiety and insomnia, but people and doctors should be aware of the longer-term risks associated with these drugs.”

“This report comes the day before the G7 Global Dementia Legacy Event in Canada where leaders will discuss how we tackle dementia through research. There are currently 850,000 people living with dementia in the UK, and with so few drugs available to treat Alzheimer’s disease, these findings show the need for us to look at how we might change prescription habits to reduce people’s risk of developing dementia.”

Prof Guy Goodwin, President of the European College of Neuropsychopharmacology, said: “Many treatments can look bad because they are given to sick people. This is “confounding by indication”, and is the bane of all epidemiological studies of drug exposure. This publication recognises the problem but may not have an adequate solution.

“The finding that benzodiazepine exposure is associated with the diagnosis of Alzheimer’s disease five years or more later could mean that the drugs cause the disease, but is more likely to mean that the drugs are being given to people who are already ill. In other words, we are seeing an association, rather than a cause.

“Non-specific symptoms arise in the 14 years before an Alzheimer diagnosis, so a five year study, as in this paper, may not be long enough to exclude what we call reverse causality; in other words symptoms in the early phases of Alzheimer’s disease may increase the probability of being prescribed a benzodiazepine.

“It is very difficult to control for this in most databases because the detail is insufficient to reconstruct the clinical reality.

“Nevertheless, benzodiazepines can impair memory by their direct effect on the brain (unrelated to dementia), and their use in the elderly always merits caution and care to balance side-effects with benefits.”

Prof John Hardy, Professor of Neuroscience at University College London, said: “The apparent association between benzodiazepines and Alzheimer’s disease is interesting and deserves further investigation.

“There are many possible explanations: it could be a true association in that it reflects benzodiazepine use in the early stage of disease (this is the reverse causation discussed by the authors), it could be caused by benzodiazepine causing minor brain damage which is clinically additive to Alzheimer disease, there could be a direct relationship between benzodiazepine drug action and the disease process, or it could be a false positive, a statistical fluke.

“Clearly more work is needed before any firm conclusions are drawn. Clinicians are already careful about benzodiazepine prescribing so I would not regard this unexplained and as of yet unreplicated study as cause for any alarm.”