People who speak more than two languages may lower their risk of memory loss or developing other memory problems, according to a study released today that will be presented at the American Academy of Neurology’s 63rd Annual Meeting in Honolulu April 9 to April 16, 2011. “It appears speaking more than two languages has a protective effect on memory in seniors who practice foreign languages over their lifetime or at the time of the study,” said study author Magali Perquin, PhD, with the Center for Health Studies from the Public Research Center for Health (“CRP-Santé”) in Luxembourg. Perquin is helping to lead the MemoVie study which involves a consortium of partners from different hospitals and institutions.
The study involved 230 men and women with an average age of 73 who had spoken or currently spoke two to seven languages. Of the participants, 44 reported memory loss or cognitive problems; the rest of the group had no memory issues. Researchers discovered that those people who spoke four or more languages were five times less likely to develop memory loss or cognitive problems compared to those people who only spoke two languages. People who spoke three languages were three times less likely to have memory loss or cognitive problems compared to bilinguals. In addition, people who currently spoke more than two languages were also four times less likely to have memory loss or cognitive impairment. The results accounted for the age and the education of the participants.
“Further studies are needed to try to confirm these findings and determine whether the protection is limited to thinking skills related to language or if it also extends beyond that and benefits other areas of cognition,” said Perquin. The research was conducted in Luxembourg, where there is a dense population of people who speak more than two languages. The MemoVie study was supported by The National Research Fund (FNR) from Luxembourg.
The study was carried out by researchers from University of Otago Medical School, New Zealand. Funding was provided by Genesis Oncology Trust, the Dean’s Bequest Funds of the Dunedin School of Medicine, the Gisborne East Coast Cancer Research Trust and the Director’s Cancer Research Trust. The research was published in the peer-reviewed American Journal of Epidemiology. This was a case-control study in New Zealand that compared a group of adults with bowel cancer, and a group without bowel cancer, and looked at whether they drank milk at school. School milk was freely available in most schools in New Zealand until 1967 when the government programme was stopped. Many schools in the Southland region stopped free milk as long ago as 1950.
Case-control studies are appropriate for looking at whether people with and without a disease have had a particular exposure (milk in this case). The difficulty is in accounting for all potential confounding factors, particularly other health and lifestyle factors, which could be related to both diet and bowel cancer risk, for example regular childhood milk consumption could be a reflection of a ‘healthy’ diet and other healthy lifestyle behaviours that may reduce risk of cancer. In addition, when examining such a specific dietary factor – ie milk consumed in school – it is difficult to account for all possible milk or other dairy products consumed outside of school.
In this case-control study, 562 adults (aged 30 to 69) with newly diagnosed bowel cancer were identified from the New Zealand Cancer Registry in 2007. For a control group, 571 age-matched adults without cancer were randomly selected from the electoral register. All participants were mailed a questionnaire that asked about any previous illness, use of aspirin or dietary supplements in childhood, participation in school milk programmes, other childhood milk consumption, childhood diet (including other milk and dairy), smoking, alcohol consumption prior to 25 years of age, screening tests for bowel cancer, family history of cancer, education and sociodemographic characteristics. Childhood weight and height were not questioned. For school milk consumption they were specifically asked:
- Whether they drank school milk
- How many half-pint bottles they drank a week
- What age they first drank school milk
- When they stopped drinking school milk
Statistical risk associations between school milk participation and cancer were calculated. The calculations took into account several risk factors for bowel cancer risk including age, sex, ethnicity and family history.
What were the basic results?
Data on school milk consumption was available for 552 cases and 569 controls. As expected, people who started school before 1967 were more likely to have had free school milk than those who began school after 1968. Seventy-eight percent of cases participated in the school milk programme compared with 82% of controls. School milk consumption was associated with a 30% reduced risk of developing bowel cancer (odds ratio 0.70, 95% confidence interval 0.51 to 0.96).
When looking at the effect of number of bottles consumed per week they found that compared with no bottles, five bottles per week was associated with 32% significantly decreased risk, and 10 or more bottles with 61% significantly decreased risk. However, there was no significant association with one to four bottles or six to nine bottles. The researchers found a similar trend when the total school consumption of milk was compared with no consumption: 1,200-1,599 bottles was associated with 38% significantly decreased risk; 1,600-1,799 with 43% decreased risk; and 1,800 or more bottles associated with 38% significantly decreased risk. There was no significant association with fewer than 1,200 bottles. The researchers calculated that for every 100 half-pint bottles consumed at school there was a 2.1% reduction in the risk of bowel cancer. Outside of school, there was a significantly reduced risk of bowel cancer with more than 20 dairy products a week compared with none to nine dairy products a week.
The researchers conclude that their national case-control study ‘provides evidence that school milk consumption was associated with a reduction in the risk of adult colorectal cancer in New Zealand. Furthermore, a dose-dependent relation was evident’. This study has strengths in its relatively large size, its reliable and nationally representative identification of cases and controls, and its thorough data collection. However, the conclusion that school milk consumption is associated with a reduced risk of bowel cancer in adulthood must be interpreted in light of a number of considerations:
The analysis took into account established risk factors for bowel cancer including age, sex, ethnicity and family history. However, many other potential confounders were not considered, including diet, physical activity, overweight and obesity, smoking or alcohol consumption. Diet in particular has been implicated in bowel cancer risk, with diets high in saturated fat, red meat and processed foods and low in fibre, fruit and vegetables thought to increase risk. Potentially, any of these lifestyle behaviours could be confounding the relationship between school milk consumption and bowel cancer and regular childhood milk consumption could be a reflection of a ‘healthy’ diet and other healthy lifestyle behaviours that reduce risk of cancer. When looking at the effect of number of bottles consumed per week, the researchers found that, compared with no bottles, five bottles were associated with 32% significantly decreased risk and 10 or more bottles with 61% significantly decreased risk. However, there was no significant association with one to four bottles or six to nine bottles. Therefore, the trend here is not very clear. Particularly as only 16 cases and 31 controls drank 10 or more bottles a week, statistical comparison between such small numbers should be viewed with caution. With many food questionnaires there is the potential for recall bias. For example, adults may have difficulty remembering how many bottles of school milk they drank many years before. When estimating their average weekly amount, it is highly possible that this could be inaccurate or that their consumption varied slightly from week to week and year to year. Particularly when researchers were using this response and combining it with the number of weeks in the school year and their total years at school to give a total number of bottles consumed at school (figures in 100s or 1,000s), there is the possibility of being incorrectly categorised. Hence, there may be less reliability when calculating risk according to the category of total milk bottles consumed. Cancer prevalence, and particularly environmental and lifestyle risk factors for cancer, can vary between countries. These findings in New Zealand may not be represented elsewhere. Of note, the researchers acknowledge that a cohort study in the UK found the opposite: increased childhood dairy consumption was associated with increased risk of bowel cancer. Case-control studies are most appropriate for looking at rare diseases, where you would expect there to be only a small number of cases developing among a large number of people. In the case of bowel cancer, which is common, the slightly more reliable cohort design could have also been used, where children who drank milk at school and those who didn’t were followed over time to see if they developed cancer. However, such a cohort would consequently need extensive long-term follow-up.
The possible association between milk/dairy consumption, or calcium intake, in childhood, or in later years, is worthy of further study. However, from this study alone, it cannot be concluded that school milk prevents bowel cancer later in life.
Choosing to eat tomatoes not only reduces a man’s risk of developing prostate cancer, but also shrinks the existing tumors, claims a new Italian study. Researchers theorize that the secret may lie in lycopene, the powerful anti-oxidant that makes tomatoes red. Lycopene helps neutralize harmful free radicals that are implicated in various kinds of cancer, cardiovascular problems, macular degeneration and other age-related illnesses. However, the benefit was strongest for prostate cancer.
In a bid to assess the prostate cancer-fighting properties of tomatoes, the researchers at the University of Naples conducted an experiment on rodents. For the purpose of the study, the researchers fed laboratory rats implanted with prostate cancer cells, with either a normal diet or that containing 10 percent tomato powder. The tomato powders were made from whole foods so the effects of eating the entire vegetable could be assessed as a nutritional supplement. The investigators noted that the animals fed on tomato powder exhibited slow progression of the disease and also had lower rates of prostate cancer. In contrast, those fed on a normal diet displayed no such benefits.
Joanna Owens, from Cancer Research Britain disagrees stated, “This study doesn’t provide enough evidence that tomatoes can reduce the risk of prostate cancer or prevent progression of the disease in humans. “Other risks such as age, family history and ethnicity are likely to play a much greater role than diet alone.” The study has been published in the journal ‘Cancer Prevention Research.’
A new study shows following a Mediterranean style diet rich in vegetables, olive oil, and fish may keep the mind sharp and slow age-related cognitive decline.The diet typified by the Italians, Greeks, and other Mediterranean cultures has already been shown to reduce the risk of heart disease, diabetes, and some types of cancer. But this and other studies are now suggesting that the diet may also have healthy benefits for the mind.
The Mediterranean diet emphasizes fruits and vegetables, fish, legumes, non-refined cereals, olive oil, and moderate wine consumption, usually at meals. Researchers found older adults who followed the diet more closely had slower rates of age-related cognitive decline than those who didn't, even after adjusting for other factors such as educational level. “The more we can incorporate vegetables, olive oil, and fish into our diets and moderate wine consumption, the better for our aging brains and bodies,” says Christy Tangney, PhD, associate professor of clinical nutrition at Rush University, in a news release.
In the study, published in the American Journal of Clinical Nutrition, researchers analyzed information gathered by the ongoing Chicago Health and Aging Project, which follows 3,759 adults over the age of 65 living on the South Side of Chicago. Every three years, the participants took tests of memory and basic math skills and filled out a questionnaire on how often they eat 139 different foods. The study follow-up time was 7.6 years on average.
Researchers looked at how closely the participants followed a Mediterranean diet and then compared it to their scores on age-related cognitive decline. Out of a maximum score of 55 for total adherence to a Mediterranean diet, the average score was 28. The results showed those with higher than average scores had a slower rate of age-related mental decline than those with lower scores. Researchers also looked at how closely the participants followed the Healthy Eating Index-2005, which is based on the 2005 Dietary Guidelines for Americans. They found no relationship between adherence to this type of diet and the rate of age-related cognitive decline.
Bouhlal and co workers reported that salt had an impact on intake but fat did not. They found that in general food intake increased with salt level, noting that compared with the 'normal' salt levels, a suppression of salt induced a 25 per cent decrease in green bean intake, whereas an addition of salt induced a 15 per cent increase in pasta intake. Contrarily to initial beliefs, the researchers observed no increase in food intake with increasing added sugar level. They said the findings indicate that two to three year old children's food intake may not be affected by its added sugar content.
The study data also showed that preschool children with a higher BMI score consumed more pasta when fat level was higher. The authors said this finding may confirm previous results which highlight fatter children prefer high-fat foods. The researcher said their results imply that fat and sugar addition could be avoided in foods for children without having an impact on palatability, allowing the energy density of children's diet to be limited.
“Furthermore, these findings suggest that there is no need to add salt to pasta which is consumed anyway. On the contrary, salt suppression in vegetables, whose intake is to be promoted, should be considered cautiously,” they said.
Source: British Journal of Nutrition
Published online ahead of print, doi: 10.1017/S0007114510003752
“The impact of salt, fat and sugar levels on toddler food intake”
Authors: S. Bouhlal, S. Issanchou, S. Nicklaus
Organophosphate pesticides act by disrupting neurotransmitters, particularly acetylcholine, which plays an important role in sustaining attention and short-term memory.
“Given that these compounds are designed to attack the nervous system of organisms, there is reason to be cautious, especially in situations where exposure may coincide with critical periods of fetal and child development,” said he study's lead author Amy Marks.
Earlier this year, a different study by researchers at Harvard University associated greater exposure to organophosphate pesticides in school aged children with higher rates of attention deficit hyperactivity disorder (ADHD) symptoms.
“These studies provide a growing body of evidence that organophosphate pesticide exposure can impact human neurodevelopment, particularly among children. We were especially interested in prenatal exposure because that is the period when a baby's nervous system is developing the most,” said Eskenazi.
More than 300 children were tested and the researchers were continuing to follow the children as they get older and expect to present more results in the years to come. The current findings were published in the journal Environmental Health Perspectives.
Source: New York Post
The research is being presented at the conference of the British Society for Research on Ageing (BSRA) in Newcastle. It was conducted by scientists at the BBSRC Centre for Integrated Systems Biology of Ageing and Nutrition (CISBAN) at Newcastle University.
Working with the theory that cell senescence – the point at which a cell can no longer replicate – is a major cause of ageing the researchers set out to investigate what effect a restricted diet had on this process. By looking at mice fed a restricted diet the team found that they had a reduced accumulation of senescent cells in their livers and intestines. Both organs are known to accumulate large numbers of these cells as animals age.
Alongside this the CISBAN scientists also found that the telomeres of the chromosomes of the mice on restricted diets were better maintained despite their ageing. Telomeres are the protective 'ends' of chromosomes that prevent errors, and therefore diseases, occurring as DNA replicates throughout an organisms lifetime but they are known to become 'eroded' over time.
The adult mice were fed a restricted diet for a short period of time demonstrating that it may not be necessary to follow a very low calorie diet for a lifetime to gain the benefits the scientists found.
Chunfang Wang, the lead researcher on this project at CISBAN, said: “Many people will have heard of the theory that eating a very low calorie diet can help to extend lifespan and there is a lot of evidence that this is true. However, we need a better understanding of what is actually happening in an organism on a restricted diet. Our research, which looked at parts of the body that easily show biological signs of ageing, suggests that a restricted diet can help to reduce the amount of cell senescence occurring and can reduce damage to protective telomeres. In turn this prevents the accumulation of damaging tissue oxidation which would normally lead to age-related disease.”
Professor Thomas von Zglinicki, who oversaw the research, said: “It's particularly exciting that our experiments found this effect on age-related senescent cells and loss of telomeres, even when food restriction was applied to animals in later life. We don't yet know if food restriction delays ageing in humans, and maybe we wouldn't want it. But at least we now know that interventions can work if started later. This proof of principle encourages us at CISBAN in our search for interventions that might in the foreseeable future be used to combat frailty in old patients.”
CISBAN is one of the six BBSRC Centres for Integrative Systems Biology. The centres represent a more than £40M investment by the Biotechnology and Biological Sciences Research Council (BBSRC) to support the development of systems biology in the UK. The centres are also supported by the Engineering and Physical Sciences Research Council.
Systems biology uses the study of a whole, interconnected system – a cell, an organism or even an ecosystem – with computer modelling to better make the outputs of biology more useful to scientists, policymakers and industry.
Prof Douglas Kell, BBSRC Chief Executive and keynote speaker at the BSRA Conference, said: “As lifespan continues to extend in the developed world we face the challenge of increasing our 'healthspan', that is the years of our lives when we can expect to be healthy and free from serious or chronic illness. By using a systems biology approach to investigate the fundamental mechanisms that underpin the ageing process the CISBAN scientists are helping to find ways to keep more people living healthy, independent lives for longer.”
Using a UK database of electronic medical records, he and his colleagues identified 367 children and adults diagnosed with Crohn's disease and 591 diagnosed with ulcerative colitis between 2005 and 2008. The researchers matched each of those people to five IBD-free individuals the same age and sex.
They then used air-quality data from government monitors to assess the average yearly levels of three air pollutants in the study subjects' residential areas.
The pollutants included nitrogen dioxide, which is produced largely by vehicles and is highest in urban, high-traffic areas; sulfur dioxide, which is produced through industrial processes, including the burning of coal and oil; and particulate matter, fine particles emitted via car exhaust, as well as power plants and other industrial sources.
Overall, Kaplan's team found no association between IBD and the three air pollutants across the study group as a whole.
However, young people — those age 23 or younger — were about twice as likely to be diagnosed with Crohn's disease if they lived in a region in the top 60 percent of nitrogen dioxide levels, versus the bottom 20 percent.
Similarly, people age 25 or younger were twice as likely to have ulcerative colitis if they lived in areas with higher sulfur dioxide levels. However, there was no evidence of a “dose-response” relationship — that is, the risk of ulcerative colitis climbing steadily as sulfur dioxide levels rose.
That lack of a dose-response, Kaplan told Reuters Health, “makes us a little more cautious about that finding.”
Indeed, he urged caution in interpreting the findings as a whole. While he and his colleagues tried to account for other factors — such as study subjects' smoking habits and socioeconomic status — they cannot rule out the possibility that something other than air pollution itself accounts for their findings.
“This is an interesting association,” Kaplan said. But, he added, the findings do not prove cause-and-effect.
As for why air pollution would affect IBD risk, Kaplan said he could only speculate, based on research into other health conditions, including heart and lung disease. Studies indicate that air pollutants can trigger inflammation in the body; that, Kaplan explained, raises the possibility that in genetically predisposed people, air pollution may trigger an inflammatory response in the intestines that leads to IBD.
Since the current study found a relationship between pollutants and IBD only in young people, the findings also raise the question of whether children and teenagers are particularly susceptible to any effects of air pollution on the risk of the digestive disorders.
Much more research is needed, Kaplan said — both larger population studies and research in animals to see how exposure to various air pollutants might affect intestinal health.
He added that no one is proposing that air pollution is the environmental cause of IBD; if it does turn out to be a factor, he said, it will likely be one of many players.
But if air pollution is confirmed as a risk factor, there would be important implications, Kaplan said, since air quality is something that can be modified.
The prospective Rotterdam Study involved 5,395 people over age 55 with no dementia at baseline. All of the participants, who lived in one section of the Rotterdam area, provided dietary information when the study began in 1990.
The researchers previously reported a similar association of vitamin E intake with a lower risk of dementia and Alzheimer's disease over six years of follow-up among the cohort.
The current study found that after 9.6 years of follow-up, 465 of the participants had developed dementia; 365 of these cases were classified as Alzheimer's disease.
Higher baseline vitamin E consumption correlated with lower long-term risk of dementia in models minimally adjusted for age only and those adjusted for age, education, apolipoprotein genotype, total caloric intake, alcohol and smoking habits, body mass index, and use of supplements (both P=0.02 for trend).
Dietary surveys indicated that margarine was by far the biggest contributor to vitamin E intake at 43.4%, followed by sunflower oil at 18.5%, butter at 3.8%, and cooking fats at 3.4%.
Participants with vitamin E intakes in the top third, averaging 18.5 mg per day, were 25% less likely to develop dementia of any kind over almost 10 years of follow-up than those in the bottom third, who averaged only 9.0 mg per day. Higher baseline vitamin E consumption correlated with lower long-term risk of dementia (both P=0.02 for trend).
While the top versus bottom tertile comparison was significant, the middle group with vitamin E intake averaging 13.5 mg per day was no less likely to develop dementia than the lowest intake group.
For Alzheimer's disease alone, the multivariate-adjusted risk was 26% lower among those with the highest intake compared with the lowest (95% confidence interval 3% to 44%, P=0.03 for trend). But intermediate intake again appeared to have no impact.
Other antioxidants — vitamin C, beta-carotene, and flavonoids — held no significant associations with dementia or Alzheimer's disease risk (multivariate adjusted P=0.50 to >0.99 for trend).
Sensitivity analyses excluding participants who reported taking supplements at baseline showed similar results.
The researchers noted that the vitamin intakes seen in the study were consistent with a typical Western diet but cautioned about the possibility of residual confounding in the observational results.
Of the participants, 15.5%, 29.7%, 28.1%, and 21.1% reported being physically inactive at teenage, at 30 years, at 50 years, and in late life respectively; the increase in cognitive impairment for those who were inactive was between 50% and 100% at each time point. When physical activity measures for all four ages were entered into a single model and adjusted for variables such as age, education, marital status, diabetes, hypertension, depressive symptoms, smoking, and BMI, only teenage physical activity status remained significantly associated with cognitive performance in old age.
Middleton added, “As a result, to minimize the risk of dementia, physical activity should be encouraged from early life. Not to be without hope, people who were inactive at teenage can reduce their risk of cognitive impairment by becoming active in later life.”
The researchers concluded that the mechanisms by which physical activity across the life course is related to late life cognition are likely to be multi-factorial. There is evidence to suggest that physical activity has a positive effect on brain plasticity and cognition and in addition, physical activity reduces the rates and severity of vascular risk factors, such as hypertension, obesity, and type II diabetes, which are each associated with increased risk of cognitive impairment.
“Low physical activity levels in today's youth may mean increased dementia rates in the future. Dementia prevention programs and other health promotion programs encouraging physical activity should target people starting at very young ages, not just in mid- and late life,” said Middleton.