Friday, May 26, 2017

Vitamin D in pregnancy may help prevent childhood asthma



A new study published today in the Journal of Allergy and Clinical Immunology has found that taking Vitamin D supplements in pregnancy can positively modify the immune system of the newborn baby, which could help to protect against asthma and respiratory infections, a known risk factor for developing asthma in childhood.
The team of researchers from King's College London looked at the effect that taking a supplement of 4,400 IU vitamin D3 per day during the second and third trimesters of pregnancy versus the recommended daily intake (RDI) of 400 IU/day, had on the immune system of the newborn.

Participants were randomised at 10 - 18 weeks of pregnancy to high or low doses of vitamin D supplements. The team then took umbilical cord bloods from 51 pregnant women to test the responsiveness of the newborn's innate immune system, which form the body's first line of defence to infection, and T lymphocyte responses, which provide longer-lasting protection.

They found that blood samples from babies born to mothers supplemented with higher vitamin D3 responded to mimics of pathogen stimulation by greater innate cytokine responses and greater IL-17A production in response to T lymphocyte stimulation. Both types of response are predicted to improve neonatal defence to infection. Given the evidence for strong immune responses in early life being associated with decreased development of asthma, the team believe the effect will likely lead to improved respiratory health in childhood.

"The majority of all asthma cases are diagnosed in early childhood implying that the origin of the disease stems in foetal and early life," said lead researcher, Professor Catherine Hawrylowicz from King's College London.

"Studies to date that have investigated links between vitamin D and immunity in the baby have been observational. For the first time, we have shown that higher Vitamin D levels in pregnancy can effectively alter the immune response of the newborn baby, which could help to protect the child from developing asthma. Future studies should look at the long-term impact on the immunity of the infant."

Dr Samantha Walker, Director of Research and Policy at Asthma UK, said "Vitamin D is a promising area of research for asthma, however this study is just the first step of many needed to explore this topic. Although this study shows that vitamin D supplementation in pregnancy may improve immune responses, much more research is needed to prove whether this does in fact lead to reduced asthma rates later in life.

Statins associated with improved heart structure and function



 Statins are associated with improved heart structure and function, according to research presented today at EuroCMR 2017.1 The benefits were above and beyond the cholesterol lowering effect of statins.

"Statins are primarily used to lower cholesterol," said lead author Dr Nay Aung, a cardiologist and Wellcome Trust research fellow, William Harvey Research Institute, Queen Mary University of London, UK. "They are highly effective in preventing cardiovascular events in patients who have had a heart attack or are at risk of heart disease."

He continued: "Statins have other beneficial, non-cholesterol lowering, effects. They can improve the function of the blood vessels, reduce inflammation, and stabilise fatty plaques in the blood vessels. Studies in mice and small studies in humans have shown that statins also reduce the thickness of heart muscle but this needed to be confirmed in a larger study."

This study investigated the association between statins and heart structure and function. The study included 4,622 people without cardiovascular disease from the UK Biobank, a large community-based cohort study. Cardiac magnetic resonance imaging was used to measure left and right ventricular volumes and left ventricular mass. Information on statin use was obtained from medical records and a self-reporting questionnaire.

The relationship between statin use and heart structure and function was assessed using a statistical technique called multiple regression which adjusts for potential confounders that can have an effect on the heart such as ethnicity, gender, age, and body mass index (BMI).

Nearly 17% of participants were taking statins. Those taking statins were older, had higher BMI and blood pressure, and were more likely to have diabetes and hypertension. "This was not surprising because we prescribe statins to patients at high risk of heart disease and these are all known risk factors," said Dr Aung.

Patients taking statins had a 2.4% lower left ventricular mass and lower left and right ventricular volumes. Dr Aung said: "People using statins were less likely to have a thickened heart muscle (left ventricular hypertrophy) and less likely to have a large heart chamber. Having a thick, large heart is a strong predictor of future heart attack, heart failure or stroke and taking statins appears to reverse the negative changes in the heart which, in turn, could lower the risk of adverse outcomes."

"It is important to note that in our study, the people taking statins were at higher risk of having heart problems than those not using statins yet they still had positive heart remodelling compared to the healthier control group," added Dr Aung.

In terms of how statins might reduce the thickness and volume of the heart, Dr Aung said several studies have demonstrated that statins reduce oxidative stress and dampen the production of growth factors which stimulate cell growth. Statins also increase the production of nitric oxide by the cells lining the blood vessels, leading to vasodilatation, improved blood flow, lower blood pressure, and lower stress on the heart, which is less likely to become hypertrophied.

The findings raise the issue of extending statin prescriptions to anyone above the age of 40, but Dr Aung said that was probably not the way to go.

"There are clear guidelines on who should receive statins," he said. "There is debate about whether we should lower the bar and the question is when do you stop. What we found is that for patients already taking statins, there are beneficial effects beyond cholesterol lowering and that's a good thing. But instead of a blanket prescription we need to identify people most likely to benefit - i.e. personalised medicine."

Dr Aung said: "A dual approach should be considered to identify people who will benefit most from statins. That means looking at not only clinical risk factors such as smoking and high blood pressure, but also genetic (hereditary) factors which can predict individuals' response to statins. This is an area of growing interest and one that we are also investigating in our lab with our collaborators."

Wednesday, May 24, 2017

Health benefits of moderate drinking may be overstated


The benefits of light alcohol consumption, as well as the risks associated with not drinking at all, might not be as great as previously thought, according to Penn State researchers who examined the drinking habits of middle-aged adults.

The researchers analyzed information about more than 9,000 people across England, Scotland and Wales born in 1958 who are participating in the longitudinal National Child Development Study. The study, based at the University College London Centre for Longitudinal Studies, tracked changes in people's drinking and cigarette smoking habits from age 23 to 55, and linked these changes to mental and physical health.

About one third of men and women who reported drinking at the light-to-moderate level were very unlikely to smoke. While this group of light drinkers and non-smokers enjoyed the best health and quality of life in middle age, three other groups experienced more health problems. These groups were those who drank lightly to moderately but also smoked; those who both drank more heavily and smoked; and those who refrained from drinking alcohol or reduced their drinking over time.

Light-to-moderate drinkers were defined as adults who consumed no more than 14 units of alcohol, which is equivalent to roughly six pints of beer or six medium-sized glasses of wine, per week. This is the current maximum recommended for men and women by the United Kingdom's Department of Health, according to Jeremy Staff, professor of criminology and sociology at Penn State and the study's lead author.

While the supposed benefits of moderate drinking have been widely reported in the media, many reports have failed to take into account other risk factors. For example, light-to-moderate drinkers suffered poor health in midlife if they were former smokers or still had the occasional cigarette. This may be due to a direct effect of smoking or because of other lifestyle-related risks, such as lack of exercise or obesity. Many midlife abstainers also began their adult life in poorer physical or mental health than peers who had completely abstained from alcohol.

"Alcohol abstainers are a diverse group. They include former heavy drinkers who quit due to problems with alcohol, as well as those who quit drinking due to poor health, and not just lifetime abstainers," said Staff. "Medical professionals and public health officials should be wary of drawing conclusions about the so-called 'dangers' of never drinking without more robust evidence."

About 1-in-5 members of 55-year-olds who said they had never drunk alcohol in their lives had previously reported drinking when they were younger. This suggests that those who drink very little may tend to misremember or under-report previous drinking habits. When studies include this group as lifetime abstainers, apparent 'harms' of abstaining may be overestimated, said the researchers.

While modest drinking habits also have been linked with higher levels of education, those with few or no educational qualifications were also among those who did not drink or drank modestly. On the other hand, men and women with the highest educational qualifications at age 23 were more likely than their peers to drink at light-to-moderate rates throughout their adult lives, and were unlikely to smoke.

Jennifer Maggs, professor of human development and family studies at Penn State and another of the study's authors, added, "Evidence continues to grow that alcohol has many health risks, including for cancer. Therefore, it is dangerous to report only benefits of moderate alcohol consumption. Drinking habits are also shaped by our education, health earlier in life, and related lifestyle factors including smoking. These other influences may be the real factors underlying the connection between drinking and midlife health."

According to Sir Ian Gilmore, Chair of the Alcohol Health Alliance in the UK, "This study provides yet more evidence that any benefits associated with drinking alcohol are smaller than previously thought. The most effective ways to reduce harms associated with alcohol consumption are to introduce pricing measures linked to alcohol sales, and enable more informed choices through public education efforts and mandatory labeling of alcohol products."

Tuesday, May 23, 2017

Just one alcoholic drink a day increases breast cancer risk, exercise lowers risk



Drinking just one glass of wine or other alcoholic drink a day increases breast cancer risk, finds a major new report by the American Institute for Cancer Research (AICR) and the World Cancer Research Fund (WCRF).

The report also revealed, for the first time, that vigorous exercise such as running or fast bicycling decreases the risk of both pre- and post-menopausal breast cancers. Strong evidence confirmed an earlier finding that moderate exercise decreases the risk of post-menopausal breast cancer, the most common type of breast cancer.

"It can be confusing with single studies when the findings get swept back and forth," said Anne McTiernan, MD, PhD, a lead author of the report and cancer prevention expert at the Fred Hutchinson Cancer Research Center.

"With this comprehensive and up-to-date report the evidence is clear: Having a physically active lifestyle, maintaining a healthy weight throughout life and limiting alcohol -- these are all steps women can take to lower their risk."

Brisk Walking, Alcohol and Breastfeeding

Diet, Nutrition, Physical Activity and Breast Cancer systematically collated and evaluated the scientific research worldwide on how diet, weight and exercise affect breast cancer risk in the first such review since 2010. The report analyzed 119 studies, including data on 12 million women and 260,000 cases of breast cancer.

The report found strong evidence that drinking the equivalent of a small glass of wine or beer a day (about 10 grams alcohol content) increases pre-menopausal breast cancer risk by 5 percent and post-menopausal breast cancer risk by 9 percent. A standard drink is 14 grams of alcohol.

For vigorous exercise, pre-menopausal women who were the most active had a 17 percent lower risk and post-menopausal women had a 10 percent lower risk of developing breast cancer compared to those who were the least active. Total moderate activity, such as walking and gardening, linked to a 13 percent lower risk when comparing the most versus least active women.

In addition the report showed that:

Being overweight or obese increases the risk of post-menopausal breast cancer, the most common type of breast cancer.
Mothers who breastfeed are at lower risk for breast cancer.
Greater adult weight gain increases risk of post-menopausal breast cancer.
Breast cancer is the most common cancer in US women with over 252,000 new cases estimated this year. AICR estimates that one in three breast cancer cases in the U.S. could be prevented if women did not drink alcohol, were physically active and stayed a healthy weight.

Emerging Findings: Dairy and Veggies

The report points to links between diet and breast cancer risk. There was some evidence -- although limited -- that non-starchy vegetables lowers risk for estrogen-receptor (ER) negative breast cancers, a less common but more challenging to treat type of tumor.

Limited evidence also links dairy, diets high in calcium and foods containing carotenoids to lowering risk of some breast cancers. Carrots, apricots, spinach and kale are all foods high in carotenoids, a group of phytonutrients studied for their health benefits.

These links are intriguing but more research is needed, says McTiernan. "The findings indicate that women may get some benefit from including more non-starchy vegetables with high variety, including foods that contain carotenoids," she said. "That can also help avoid the common 1 to 2 pounds women are gaining every year, which is key for lowering cancer risk."

Steps Women Can Take

Aside from these lifestyle risk factors, other established causes of breast cancer include being older, early menstrual period and having a family history of breast cancer.

While there are many factors that women cannot control, says Alice Bender, MS, RDN, AICR's Head of Nutrition Programs, the good news from this report is that all women can take steps to lower their breast cancer risk.

"Wherever you are with physical activity, try to nudge it up a bit, either a little longer or a little harder. Make simple food shifts to boost protection -- substitute veggies like carrots, bell peppers or green salad for chips and crackers and if you drink alcohol, stick to a single drink or less," said Bender.

"There are no guarantees when it comes to cancer, but it's empowering to know you can do something to lower your risk."


Recommended daily protein intake too low for the elderly



You can find the recommended dietary allowance (RDA) on the nutrition labels of all your processed food. Food manufacturers are obliged to list the nutritional value of their products, and therefore must mention the percent daily value of the RDA their product meets for certain nutrients.

These RDA guidelines are put together by the Food and Nutrition Board of the National Academy of Sciences' Institute of Medicine. They inform you how much of a specific nutrient your body minimally needs every day. They are set to meet the requirements of 97.5% of the healthy individuals older than 19 years.

The RDA you will find on the nutrition labels on your food, however, were set in 1968, and the ones used by researchers and professionals were set in 2003. A recent review published in Frontiers in Nutrition points out that both these values do not do justice to the protein needs of the elderly and critically ill.

"A big disservice is being done. The prescribed 0.8 g/kg/day just isn't enough protein for the elderly and people with a clinical condition. This shouldn't be communicated as what is 'allowed' or even 'recommended' to eat.", author Stuart Phillips of McMaster University in Canada explains.

In his review, he points out that the quality of proteins should be considered when setting the RDA guidelines and recommending protein supplements. He argues that there should be a stronger focus on leucine; an indispensable amino acid and building block for proteins. The elderly have a higher need for leucine to build muscle proteins, and milk-based proteins (e.g. milk and whey) are a good source for this.

Moreover, it may be highly beneficial for the critically ill patients that rapidly lose lean body mass (i.e. the body weight minus body fat) to increase their protein intake. Again, elderly ill patients would benefit the most from this. "I think it's clear we need some longer-term clinical trials with older people on higher protein intakes. These trials need to consist of around 400 - 500 people.", Phillips argues.

He is not the first researcher to challenge the current protein RDA, and hopes his message does not fall on deaf ears. That is also why he chose to publish Open Access: "I love to publish work that everyone can read. The days of publishing a paper that only people in academic institutions can read are over. I think it is essential that everyone and not only your scientific colleagues can read the work we do."

At his own dinner table, Phillips also puts the focus on proteins. "But not at the expense of other macronutrients. I enjoy a variety of foods, and the only thing I specifically focus on is limiting my intake of sugar and refined carbohydrates. But of course, given the benefits of proteins, they are a big part of what I think about when planning my meals."

Rethinking exercise: Replace punishing workouts with movement that makes you happy


Many women start fitness programs to lose weight, and when they don't, they feel like failures and stop exercising.

And then, months or a year later, they do the same thing again--creating a vicious cycle that fails to consider what might be leading to short-term motivation, says Michelle Segar, director of the University of Michigan's Sport, Health, and Activity Research and Policy Center.

In a new study funded internally by the National Cancer Institute, Segar and co-investigators analyzed what women say makes them feel happy and successful, and how their expectations and beliefs about exercise foster or undermine those things.

"A new understanding of what really motivates women might make an enormous difference in their ability to successfully incorporate physical activity into their daily routine--and have fun doing it," said Segar, who is also a researcher at the U-M Institute for Research on Women and Gender.

The findings, which will appear in the journal BMC Public Health, show that both active and inactive women report the same ingredients for feeling happy and successful:

Connecting with and helping others be happy and successful.

Being relaxed and free of pressures during their leisure time. Accomplishing goals of many sorts (from grocery shopping to career goals).

But the study also found that for inactive women, their beliefs and expectations about exercise actually thwarted the things that make them feel happy and successful:

They believe "valid" exercise must be intense, yet they want to feel relaxed during their leisure time.

They feel pressured to exercise for health or to lose weight, yet during their leisure time they want to be free of pressures. Success comes from achieving goals, yet their expectations about how much, where and how they should be exercising means they can't achieve these goals.

"The direct conflict between what these low-active women believe they should be doing when they exercise, and their desire to decompress and renew themselves during leisure time, demotivates them," Segar said. "Their beliefs about what exercise should consist of and their past negative experiences about what it feels like actually prevents them from successfully adopting and sustaining physically active lives."

Segar and co-investigators Jennifer Taber, Heather Patrick, Chan Thai and April Oh conducted eight focus groups among white, black and Hispanic women aged 22-49 who were either categorized as "high active" or "low active."

While the findings about happiness and success seemed to hold true for both groups in the different demographics, low-active women held distinctly different views than high-active women about exercising.

"We've all been socialized to exercise and be physically active for the last 30 years," said Segar. "The traditional recommendation we've learned to believe is that we should exercise at a high intensity for at least 30 minutes, for the purpose of losing weight or improving our health. Even though there are newer recommendations that permit lower intensity activity in shorter durations most people don't know or even believe it."

This more traditional message has worked for a small minority of the population, but more generally it has failed to increase population physical activity, she says.

"This traditional approach to exercising might actually harm exercise motivation. Our study shows that this exercise message conflicts with and undermines the very experiences and goals most women have for themselves," she said.

The exceptions found in the study were among the more active participants, who held more flexible views of exercise. They expressed that it "was not the end of the world" if they had to skip exercising once in awhile. They made exercise more of a "middle priority," which took the pressure off and left room for compromise when schedules and responsibilities did not permit planned exercise to occur.

The high-active women seemed to have more positive feelings from exercising, in contrast to most of the low-active women, who, in general, tended to dread the very idea of it.

"There are important implications from this study on how we can help women better prioritize exercise in their day-to-day life," Segar said. "We need to re-educate women they can move in ways that will renew instead of exhaust them, and more effectively get the message across that any movement is better than nothing. To increase motivation to be physically active, we need to help women to want to exercise instead of feeling like they should do it."

This can be achieved by:

  • Re-educating women that movement can and should feel good to do.
  • Promoting physical activity as a way to connect with important others.
  • Reframing physical activity as a vehicle that helps women renew and re-energize themselves to better succeed at their daily roles and goals.
  • Explain physical activity as a broad continuum that counts all movement as valid and worth doing.

Probiotics may relieve symptoms of depression


Probiotics may relieve symptoms of depression, as well as help gastrointestinal upset, research from McMaster University has found.

In a study published in the medical journal Gastroenterology (May 2), researchers of the Farncombe Family Digestive Health Research Institute found that twice as many adults with irritable bowel syndrome (IBS) reported improvements from co-existing depression when they took a specific probiotic than adults with IBS who took a placebo.

The study provides further evidence of the microbiota environment in the intestines being in direct communication with the brain said senior author Dr. Premysl Bercik, an associate professor of medicine at McMaster and a gastroenterologist for Hamilton Health Sciences.

"This study shows that consumption of a specific probiotic can improve both gut symptoms and psychological issues in IBS. This opens new avenues not only for the treatment of patients with functional bowel disorders but also for patients with primary psychiatric diseases," he said.

IBS is the most common gastrointestinal disorder in the world, and is highly prevalent in Canada. It affects the large intestine and patients suffer from abdominal pain and altered bowel habits like diarrhea and constipation. They are also frequently affected by chronic anxiety or depression.

The pilot study involved 44 adults with IBS and mild to moderate anxiety or depression. They were followed for 10 weeks, as half took a daily dose of the probiotic Bifidobacterium longum NCC3001, while the others had a placebo.

At six weeks, 14 of 22, or 64%, of the patients taking the probiotic had decreased depression scores, compared to seven of 22 (or 32%) of patients given placebo.

Functional Magnetic Resonance Imaging (fMRI) showed that the improvement in depression scores was associated with changes in multiple brain areas involved in mood control.

"This is the result of a decade long journey - from identifying the probiotic, testing it in preclinical models and investigating the pathways through which the signals from the gut reach the brain," said Bercik.

"The results of this pilot study are very promising but they have to be confirmed in a future, larger scale trial," said Dr. Maria Pinto Sanchez, the first author and a McMaster clinical research fellow.

The study was performed in collaboration with scientists from Nestlé.