A diet rich in nuts improves sperm count and motility

The inclusion of nuts in a regular diet significantly improves the quality and function of human sperm, according to results of a randomised trial which measured conventional semen parameters and molecular changes over a 14-week study period. The findings, say the investigators, "support a beneficial role for chronic nut consumption in sperm quality" and reflect a research need for further male-specific dietary recommendations.
The results of the study are presented today by Dr Albert Salas-Huetos from the Human Nutrition Unit of the Universitat Rovira i Virgil in Reus, Spain.(1)
The study was performed, he said, against a background of general decline in quantity and quality of human sperm, attributed in industrialised countries to "pollution, smoking, and trends toward a western-style diet".(2) In this study subjects randomised to the nut group had significant improvements in their sperm count, vitality, motility and morphology (shape); these were consistent with improvements found in other recent studies with diets rich in omega-3, antioxidants (eg, vitamin C and E, selenium and zinc), and folate. Nuts are dense foods containing many of these nutrients and other phytochemicals.
The study was a 14-week randomised clinical trial in which 119 healthy young men aged 18-35 were allocated to either their usual western-style diet supplemented with 60 grams/day of mixed almonds, hazelnuts and walnuts, or their usual western-style diet without nuts. In its analysis the study recorded not just sperm parameters (according to WHO benchmarks) but also changes in several molecular factors, including sperm DNA fragmentation.(3) Sperm and blood samples were analysed at baseline and after 14 weeks of intervention.
Results firstly found significantly higher levels of sperm count, vitality, motility and morphology in the men randomised to the 60 g/day nut diet than in those following their usual diets free of nuts. Improvements in the former group were by around 16% in sperm count, 4% in sperm vitality, 6% in sperm motility, and 1% in morphology. These four parameters, explained Salas-Huetos, are all associated with male fertility. Moreover, the subjects in the nut group also showed a significant reduction in their levels of sperm DNA fragmentation, a parameter closely associated with male infertility. Indeed, it was this change in the level of DNA fragmentation in the sperm cells by which the investigators explained, at least in part, the improvement in sperm count, motility and morphology.
Although these are statistically significant results from a randomised trail with a high level of scientific evidence, Salas-Huetos emphasised that subjects in the study were all healthy and apparently fertile men following a western-style diet. He thus warned that results cannot be extrapolated to the general population.
So should men hoping to conceive a baby - either naturally or with IVF - add nuts to their everyday diet? "We can't yet say that," said Salas-Huetos, "based solely on the results of this study. But evidence is accumulating in the literature that healthy lifestyle changes such as following a healthy dietary pattern might help conception - and of course, nuts are a key component of a Mediterranean healthy diet."

Healthy diet may lower eye disease risk

An analysis of recent high-quality research reveals that diet may affect individuals' risks related to the development and progression of age-related macular degeneration (AMD). The findings are published in Clinical & Experimental Ophthalmology.

The systematic review included the analysis of 18 high-quality studies. Adherence to a Mediterranean diet was linked with a decreased risk of AMD progression. An Oriental diet pattern (with higher intake of vegetables, legumes, fruit, whole grains, tomatoes, and seafood) had decreased association with AMD prevalence, whereas a Western diet pattern (with higher intake of red meat, processed meat, high-fat dairy products, fried potatoes, refined grains and eggs) had increased association with AMD prevalence.

High consumption of vegetables rich in carotenoids and fatty fish containing omega-3 fatty acids was beneficial for those at risk of AMD. High glycaemic index diets and alcohol consumption of greater than two drinks a day had increased association with AMD.

"Improving the quality of the diet, increasing the intake of foods that contain the nutrients required by the retina. and avoiding foods that induce oxidative damage will play an important role in protecting against AMD," said lead author Naoko Chapman, of the University of Auckland, in New Zealand.

'Skinny fat' in older adults may predict dementia, Alzheimer's risk

A new study has found that "skinny fat" - the combination of low muscle mass and strength in the context of high fat mass - may be an important predictor of cognitive performance in older adults. While sarcopenia, the loss of muscle tissue that is part of the natural aging process, as well as obesity both negatively impact overall health and cognitive function, their coexistence poses an even higher threat, surpassing their individual effects.
The study, published in the journal Clinical Interventions in Aging, was led by researchers at Florida Atlantic University's Comprehensive Center for Brain Health in the Charles E. Schmidt College of Medicine.
Using data from a series of community-based aging and memory studies of 353 participants, the researchers assessed the relationship of sarcopenic obesity or skinny fat with performance on various cognition tests. The average age of the participants was 69. Data included a clinic visit, valid cognitive testing such as the Montreal Cognitive Assessment and animal naming; functional testing such as grip strength and chair stands; and body composition (muscle mass, body mass index, percent of body fat) measurements.
Results from the study show that sarcopenic obesity or "skinny fat" was associated with the lowest performance on global cognition, followed by sarcopenia alone and then obesity alone. Obesity and sarcopenia were associated with lower executive function such as working memory, mental flexibility, self-control and orientation when assessed independently and even more so when they occurred together.
Using a cross-sectional design, the researchers found consistent evidence to link sarcopenic obesity to poor global cognitive performance in the study subjects. This effect is best captured by its sarcopenic component with obesity likely having an additive effect. This effect extends to specific cognitive skills, in particular executive function.
"Sarcopenia has been linked to global cognitive impairment and dysfunction in specific cognitive skills including memory, speed, and executive functions," said senior author James E. Galvin, M.D., M.P.H., one of the most prominent neuroscientists in the country, associate dean for clinical research and a professor of integrated medical science in FAU's Schmidt College of Medicine, and a professor in FAU's Christine E. Lynn College of Nursing. "Understanding the mechanisms through which this syndrome may affect cognition is important as it may inform efforts to prevent cognitive decline in later life by targeting at-risk groups with an imbalance between lean and fat mass. They may benefit from programs addressing loss of cognitive function by maintaining and improving strength and preventing obesity."
Obesity may contribute to the risk of impaired executive function through vascular, behavioral, metabolic, and inflammatory mechanisms or can result from reduced impulse control, self-monitoring, and goal-directed behavior in individuals with impaired executive function with a negative effect on the ability to maintain energy balance. The exact mechanisms linking obesity to cognitive dysfunction are yet to be determined, although several pathways including sedentary behavior, inflammation, and vascular damage have been proposed. Sarcopenia, in turn, has been linked to impairments in abilities that relate to conflict resolution and selective attention. Executive function is reduced in obese older adults, and improvement in muscular function has been linked to enhancement of executive function in senior adults.
Galvin and his study collaborators, Magdalena I. Tolea, Ph.D., a research assistant professor of integrated medical science, and Stephanie Chrisphonte, M.D., a research assistant professor of integrated medical science, both in FAU's Schmidt College of Medicine, caution that changes in body composition including a shift toward higher fat mass and decreased lean muscle mass represent a significant public health concern among older adults as they may lead to various negative health outcomes including cardiovascular and neurodegenerative diseases.
"Sarcopenia either alone or in the presence of obesity, can be used in clinical practice to estimate potential risk of cognitive impairment," said Tolea. "Testing grip strength by dynamometry can be easily administered within the time constraints of a clinic visit, and body mass index is usually collected as part of annual wellness visits."

Consumption of fast food linked with asthma and other allergic diseases

A new Respirology review and analysis of published studies reveals a link between fast food consumption and an increased likelihood of having asthma, wheeze, and several other allergic diseases such as pollen fever, eczema, and rhino-conjunctivitis.

The analysis included 16 studies. In terms of different types of fast food consumption, hamburger intake was most prominently associated with allergic diseases in a dose-dependent manner, irrespective of consumers' income.

The authors note that poor quality diet is likely to contribute to the development and progression of asthma and wheeze via multiple mechanisms. "Additional studies are needed to confirm the relationships seen in this analysis, however, and to identify potential causal associations between the consumption of fast food and allergic diseases," said senior author Dr. Gang Wang, of West China Hospital, Sichuan University.

Mindfulness imay bring tinnitus relief

New UK research has found that a new mindfulness based approach to tinnitus could transform the treatment of the condition.

Published in the journals Ear and Hearing and Psychotherapy and Psychosomatics, the research led by Dr Laurence McKenna from University College London Hospitals NHS Foundation Trust (UCLH) and Dr Liz Marks, from Department of Psychology at the University of Bath, found that Mindfulness based Cognitive Therapy (MBCT) helps to significantly reduce the severity of tinnitus compared to relaxation-based treatments, an approach recommended by many tinnitus clinics.
Tinnitus, described as a sensation or awareness of sound that is not caused by an external sound source, affects approximately six million people in the UK - 10 percent of the UK's population. Approximately 1 in 100 people are very distressed or disabled by it and as many as 1 in 20 people are at least moderately distressed by it. Tinnitus is associated with complaints of emotional stress, insomnia, auditory perceptual problems and concentration problems.
As yet there is no treatment to stop the tinnitus noise but this research, funded by the British Tinnitus Association (BTA), shows clearly that treatment can make it less severe, intrusive and bothersome.
Dr Liz Marks, from the Department of Psychology at the University of Bath, will explore the report's findings in more detail at the BTA's annual conference in Birmingham in September. She said: "We compared MBCT to relaxation therapy, a traditional treatment for people with chronic tinnitus, to determine if MBCT was a better option than the current recommended practice.
"In total 75 patients took part in the trial at UCLH's Royal National Throat, Nose and Ear Hospital receiving either MBCT or relaxation therapy. The study found that both treatments led to a reduction in tinnitus severity, psychological distress, anxiety and depression for patients.
"However, the MBCT treatment led to significantly greater reductions in tinnitus severity than the relaxation treatment, and this improvement lasted for longer. In addition, 182 patients who completed MBCT routinely in our clinic showed a similar level of improvement."
Relaxation therapy provides patients with specific skills to reduce stress arousal levels. In contrast, MBCT, taught by highly-trained clinical psychologists, teaches patients to pay purposeful, present-moment attention to experiences, rather than trying to supress those experiences. Practicing mindfulness meditation in this way can cultivate a more helpful way of responding to tinnitus. People learn how to 'allow' and 'accept' tinnitus, rather than having to 'fight it' or 'push it away'. Mindfulness does not aim to change the nature or sound of the tinnitus, but the therapy can lead to tinnitus becoming less intrusive, to a point where it is no longer a problem for people.
Dr Marks added: "MBCT turns traditional tinnitus treatment on its head - so rather than trying to avoid or mask the noise, it teaches people to stop the battle with tinnitus.
"The mindfulness approach is radically different from what most tinnitus sufferers have tried before, and it may not be right for everyone. We are confident, however, that the growing research base has demonstrated how it can offer an exciting new treatment to people who may have found that traditional treatment has not been able to help them yet. We hope the results of our research will be one of the first steps to MBCT becoming more widely adopted."
David Stockdale, chief executive of the British Tinnitus Association, said: "The results of this research are extremely encouraging particularly for people with chronic tinnitus who find that current treatments are not working for them. We really hope that more people will be able to benefit from this approach moving forward."
"Funding this kind of innovative research is a major part of what we do here at the BTA but as a charity, we rely heavily on the donations made to us. We hope more people will support us as we work tirelessly to grow the understanding and knowledge around tinnitus in order to help people with the condition to manage."
Dr McKenna and Dr Marks are now continuing their research in tinnitus looking at how Cognitive Behavioural Therapy can be used to treat tinnitus related insomnia.

A lower risk of death associated with drinking more coffee

Coffee is popular around the globe and studies have generally reported inverse associations (moving in opposite directions) between its consumption and the risk of chronic diseases and death. But what about heavy coffee drinking and people with genetic variations that can affect how they metabolize caffeine?

A new study of nearly half a million people in the United Kingdom suggests a lower risk of death was associated with drinking more coffee, including among coffee drinkers who have eight or more cups per day, in both slow and fast metabolizers of caffeine, and in drinkers of ground, instant and decaffeinated coffee.

The results come with a warning to interpret them with caution because they are based on observational data and cannot prove causation.

Chronic inflammation tied to dementia

IMAGE: Brain scans showing white matter damage. view more 

Credit: Gottesman lab

Researchers at Johns Hopkins have added to evidence that rising and chronic inflammation as measured by a biomarker in the blood in middle and late age are linked to visible structural changes in the brains of people with poor cognition and dementia.
The authors say results of their study, based on data gathered from a federally funded study on more than 1,500 people, suggests that efforts to curb inflammation with drugs or lifestyle changes midlife or earlier may be key to delaying or preventing cognitive decline in old age.
"We found that individuals who had an increase in inflammation during midlife that was maintained from mid to late life have greater abnormalities in the brain's white matter structure, as measured with MRI scans," says Keenan Walker, Ph.D., lead author and postdoctoral fellow in the Department of Neurology at the Johns Hopkins University School of Medicine.
"This suggests to us that inflammation may have to be chronic, rather than temporary, to have an adverse effect on important aspects of the brain's structure necessary for cognitive function," he adds.
Researchers have long gathered evidence that chronic inflammation and the biochemicals associated with it may damage the brain. C-reactive protein, an inflammatory factor made in the liver, for example, already has become a marker for chemical damage to heart and blood vessel tissue indicative of heart attack.
So far, however, according to Walker, studies linking inflammation to brain abnormalities have not looked at these factors and features over an extended period of time in the same population.
In their new study, described in the August issue of Neurobiology of Aging, Walker and his colleagues took data from the atherosclerosis risk in communities (ARIC) study that looked at brain structure and integrity, as well as a marker of inflammation over a 21-year period spanning middle age to late life.
Specifically, the investigators focused on and compared data on 1,532 participants recruited from 1987 to 1989 from Washington County, Maryland; Forsyth County, North Carolina; Minneapolis, Minnesota; and Jackson, Mississippi. Sixty-one percent of participants were women, and 28 percent were African-American. At the final visit, participants were an average age of 76.
Over the course of the ARIC study, each participant had five visits with study coordinators, averaging every three years. At the last visit, each participant underwent an MRI of their brain to examine evidence of damage to so-called white matter -- the part of the brain responsible for transmitting messages. Damaged white matter appears superwhite on a scan, similar to overexposure on a photograph, and was measured using an automated program.
At visits 2, 4 and 5, the researchers took blood samples to measure for high-sensitivity C-reactive protein, a standard measure of inflammation throughout the body. Those with levels below 3 milligrams per liter were considered to have low inflammation, whereas those with 3 or more milligrams per liter of C-reactive protein were considered to have elevated inflammation.
Even after adjusting for demographics (e.g., sex and education) and cardiovascular disease risk, the researchers found that the 90 people who transitioned from low to persistently elevated C-reactive protein during midlife, indicating increasing inflammation, showed the greatest damage to the white matter in the brain.
Using a program that measures structural integrity at the microscopic level, the researchers estimate that the brains of the people who had escalating C-reactive protein in middle age appear similar to that of a person 16 years older.
Walker says because their findings overall showed that increasing and chronic inflammation were associated with the most damage to white matter, there is more reason to infer a cause and effect relationship between growing and persistent inflammation and evidence of dementia. But he emphasized that theirs was an "observational" study not designed to determine cause and effect, or to prove it. More studies would need to be done to prove cause and effect and figure out the precise pathways to brain damage, he added.
"Our work is important because currently there aren't treatments for neurodegenerative diseases, and inflammation may be a reversible factor to prolong or prevent disease onset," says Rebecca Gottesman, M.D., Ph.D., senior author and professor of neurology and epidemiology at Johns Hopkins. "Now, researchers have to look at how we might reduce inflammation to reduce cognitive decline and neurodegeneration."
Walker says that common causes of chronic inflammation include cardiovascular disease, heart failure, diabetes, high blood pressure and infections such as hepatitis C or HIV. He also says that inflammation is a normal byproduct of aging, but poor physical health and injuries seem to exacerbate it.
Some studies suggest that reducing inflammation in the short term can be accomplished by treating and controlling common cardiovascular diseases and maintaining a healthy weight.