All Posts tagged team

Yet another benefit of green tea

For thousands of years, the people of China, Japan, India, and Thailand have consumed green tea and used it medicinally to treat everything from headaches to heart diseases. Over the past few decades, however, research in both Asia and the West have taken place providing scientific evidence of green tea’s numerous health benefits. As a whole, studies indicate that regular consumption of green tea may slow or prevent conditions including high cholesterol, heart disease, arthritis, impaired immune disease and liver disease. In yet another recent study on the beverage’s healthful properties, published in the academic journal Phytomedicine, researchers have found evidence that enzymes in the drink may help in fighting Alzheimer’s and other forms of dementia.

Researchers at the Newcastle University have also found that the Chinese brew may also play a vital role in guarding against cancer. The Newcastle team focused on whether or not once the tea was in the digestive system if the protective properties were still as effective. “What was really exciting was that we found when green tea is digested, the resulting chemicals are actually more effective against key triggers of Alzheimer’s,” said Ed Okello, from the university’s School of Agriculture, Food and Rural Development. “The digested compounds also had anti-cancer properties, significantly slowing down the growth of tumour cells which we were using in our experiments,” Okello said.

Previous studies have shown that polyphenols, present in black and green tea, bind with the toxic compounds and protect brain cells. When ingested, the polyphenols are broken down to produce a mix of compounds and it was these the team tested in their research. According to Okello, there are many factors that together have an influence on diseases such as cancer and dementia – a good diet, plenty of exercise and a healthy lifestyle are all important. “But I think it’s fair to say that at least one cup of green tea a day may be good for you and I would certainly recommend it,” he added.

More

Protective properties of green tea

Regularly drinking green tea could protect the brain against developing Alzheimer’s and other forms of dementia. The study, published in the academic journal Phytomedicine, also suggests this ancient Chinese remedy could play a vital role in protecting the body against cancer. Led by Dr Ed Okello, the Newcastle team wanted to know if the protective properties of green tea – which have previously been shown to be present in the undigested, freshly brewed form of the drink – were still active once the tea had been digested. Digestion is a vital process which provides our bodies with the nutrients we need to survive. But, says Dr Okello, it also means that just because the food we put into our mouths is generally accepted to contain health-boosting properties, we can’t assume these compounds will ever be absorbed by the body.

“What was really exciting about this study was that we found when green tea is digested by enzymes in the gut, the resulting chemicals are actually more effective against key triggers of Alzheimer’s development than the undigested form of the tea,” explains Dr Okello, based in the School of Agriculture, Food and Rural Development at Newcastle University and executive director of the university’s Medicinal Plant Research Group. “In addition to this, we also found the digested compounds had anti-cancer properties, significantly slowing down the growth of the tumour cells which we were using in our experiments.”

As part of the research, the Newcastle team worked in collaboration with Dr Gordon McDougall of the Plant Products and Food Quality Group at the Scottish Crop Research Institute in Dundee, who developed technology which simulates the human digestive system. It is this which made it possible for the team to analyse the protective properties of the products of digestion. Two compounds are known to play a significant role in the development of Alzheimer’s disease – hydrogen peroxide and a protein known as beta-amyloid. Previous studies have shown that compounds known as polyphenols, present in black and green tea, possess neuroprotective properties, binding with the toxic compounds and protecting the brain cells.

When ingested, the polyphenols are broken down to produce a mix of compounds and it was these the Newcastle team tested in their latest research. “It’s one of the reasons why we have to be so careful when we make claims about the health benefits of various foods and supplements,” explains Dr Okello. “There are certain chemicals we know to be beneficial and we can identify foods which are rich in them but what happens during the digestion process is crucial to whether these foods are actually doing us any good.” Carrying out the experiments in the lab using a tumour cell model, they exposed the cells to varying concentrations of the different toxins and the digested green tea compounds.

Dr Okello explained: “The digested chemicals protected the cells, preventing the toxins from destroying the cells. “We also saw them affecting the cancer cells, significantly slowing down their growth. Green tea has been used in Traditional Chinese medicine for centuries and what we have here provides the scientific evidence why it may be effective against some of the key diseases we face today.”

The next step is to discover whether the beneficial compounds are produced during digestion after healthy human volunteers consume tea polyphenols. The team has already received funding from the Biotechnology and Biological Sciences Research Council (BBSRC) to take this forward. Dr Okello adds: “There are obviously many factors which together have an influence on diseases such as cancer and dementia – a good diet, plenty of exercise and a healthy lifestyle are all important. “But I think it’s fair to say that at least one cup of green tea every day may be good for you and I would certainly recommend it.”

(Source: Newcastle University: Phytomedicine)

More

Obesity may interfere with Vitamin D absorption

The more obese a person is, the poorer his or her vitamin D status, a new study by a team of Norwegian researchers suggests. The study found an inverse relationship between excess pounds and an insufficient amount of vitamin D, which is critical to cell health, calcium absorption and proper immune function. Vitamin D deficiency can raise the risk for bone deterioration and certain types of cancer. The researchers also suggest that overweight and obese people may have problems processing the vitamin properly.

The team noted that after the so-called “sunshine vitamin” is initially absorbed (through either sun exposure or the consumption of such foods as oily fish and fortified milk), the body must then convert it into a usable form, called 1,25-dihydroxyvitamin D. This conversion process, however, seems to be short-circuited among obese people, complicating efforts to gauge their true vitamin D health.

The findings are published in the January issue of the Journal of Nutrition.

To investigate the impact of obesity on vitamin D absorption, the team spent six years tracking 1,464 women and 315 men, with an average age of 49. Based on the participants' body mass index (BMI), an indicator of body fatness calculated from a persons weight and height, the average participant was deemed to be obese. About 11 percent were categorized as “morbidly obese.”

From the outset, overall vitamin D levels were found to be below the healthy range, the authors noted. By the end of the study, overall levels of vitamin D were found to have dropped off “significantly” while BMI readings rose by 5 percent. The research team concluded that having a higher-than-normal weight, body fat and BMI was linked to a poorer vitamin D profile. For example, people with the lowest BMI readings had 14 percent higher vitamin D levels than those with the highest BMI readings. Because vitamin D levels did not correlate properly with 1,25-dihydroxyvitamin D levels (and in fact appeared to have an abnormal inverse relationship), the authors suggested that future efforts to explore vitamin D status among obese people should test for both measures of vitamin D health.

They also suggested that people who are overweight and obese might benefit from vitamin D supplementation and more exposure to sunlight.

SOURCE: Journal of Nutrition, news release, Dec. 14, 2010

More

Obesity may interfere with Vitamin D absorption

The more obese a person is, the poorer his or her vitamin D status, a new study by a team of Norwegian researchers suggests. The study found an inverse relationship between excess pounds and an insufficient amount of vitamin D, which is critical to cell health, calcium absorption and proper immune function. Vitamin D deficiency can raise the risk for bone deterioration and certain types of cancer.

The researchers also suggest that overweight and obese people may have problems processing the vitamin properly.

The team noted that after the so-called “sunshine vitamin” is initially absorbed (through either sun exposure or the consumption of such foods as oily fish and fortified milk), the body must then convert it into a usable form, called 1,25-dihydroxyvitamin D. This conversion process, however, seems to be short-circuited among obese people, complicating efforts to gauge their true vitamin D health.

The findings are published in the January issue of the Journal of Nutrition.

To investigate the impact of obesity on vitamin D absorption, the team spent six years tracking 1,464 women and 315 men, with an average age of 49. Based on the participants' body mass index (BMI), an indicator of body fatness calculated from a persons weight and height, the average participant was deemed to be obese. About 11 percent were categorized as “morbidly obese.”

From the outset, overall vitamin D levels were found to be below the healthy range, the authors noted. By the end of the study, overall levels of vitamin D were found to have dropped off “significantly” while BMI readings rose by 5 percent.

The research team concluded that having a higher-than-normal weight, body fat and BMI was linked to a poorer vitamin D profile. For example, people with the lowest BMI readings had 14 percent higher vitamin D levels than those with the highest BMI readings. Because vitamin D levels did not correlate properly with 1,25-dihydroxyvitamin D levels (and in fact appeared to have an abnormal inverse relationship), the authors suggested that future efforts to explore vitamin D status among obese people should test for both measures of vitamin D health.

They also suggested that people who are overweight and obese might benefit from vitamin D supplementation and more exposure to sunlight.

SOURCE: Journal of Nutrition, news release, Dec. 14, 2010

More

Diet Advice can help control diabetes

Individuals with either type 1 or type 2 diabetes know that maintaining a nutritious diet is one of the most important things they can do to control their disease. The findings of a new study suggest that the services of a registered dietitian may help individuals accomplish this goal.

A team of investigators from the American Dietetic Association reviewed evidence from previous research and summarized their findings in a report published in the Journal of the American Dietetic Association.

In their write-up, researchers laid out a set of exhaustive dietary guidelines for individuals affected by diabetes. Researchers said that the services of registered dietitians may be key in helping individuals follow the guidelines, which could help them significantly improve their condition.

“The evidence is strong that medical nutrition therapy provided by registered dietitians is an effective and essential therapy in the management of diabetes. Registered Dietitians are uniquely skilled in this process,” said Marion Franz, who led the investigation.

The guidelines developed by the research team lay out 29 nutritional points that can help diabetics improve their blood sugar control.

More

Tylenol linked to asthma

A new study shows that adolescents who take acetaminophen, better known as Tylenol, have a higher risk of asthma, allergic nasal conditions and the skin disorder eczema.

Acetaminophen is widely viewed as a very safe drug—one reason why hospitals use it routinely as a painkiller instead of aspirin or ibuprofen. The major problem associated with it is liver damage caused by overdoses. Recently, however, there has been a growing drumbeat about possible dangers from the drug. One study, for example, found that acetaminophen increased the risk of hearing loss in men. And some others have hinted that the drug is linked to asthma in newborns whose mothers used the drug during pregnancy and in young children exposed to it.

The new findings were reported in the American Journal of Respiratory and Critical Care Medicine by researchers in the International Study of Asthma and Allergies in Childhood. The team, headed by epidemiologist Richard Beasley of the Medical Research Institute in Wellington, New Zealand, gave written questionnaires to 322,959 13- and 14-year-olds in 50 countries exploring their use of acetaminophen, other drugs, and asthma symptoms. They were also shown a video containing five scenes of clinical asthma and asked whether they had experienced any symptoms similar to those shown. About 73% of the teens said they had used acetaminophen at least once in the previous year and 30% said they had used it monthly.

Taking into account maternal education, smoking, diet and siblings, the team found that those subjects who had used the drug at least once per year were 43% more likely to have asthma, while those who used it at least monthly were 2.5 times as likely to suffer from the condition. The risk of rhinoconjunctivitis (a severe nasal congestion) was 38% higher for those who used it once per year and 2.39 times as high for those who used it at least monthly. The comparable increases in risk for eczema were 31% and 99%, respectively.

Overall, the increased risk of asthma associated with acetaminophen was 41%, the authors found. That could, at least in part, explain why there has been an increase in the prevalence of asthma in the 50 years since the drug was introduced. Given the widespread use of the drug, it could also represent a large public health problem.

But—and it is a very big but—the study shows only an association, not causality. That could only be determined by a randomized clinical trial, which the authors recommend. Furthermore, the study relies on the recall of teenagers. Recall is notoriously inaccurate in adults, and it is probably worse in adolescents, clouding the results. For the time being then, you can probably continue to feel comfortable giving the drug to your children.

In a statement, McNeil Consumer Healthcare, which manufactures Tylenol, said that the drug “has over 50 years of clinical history to support its safety and effectiveness” and that no clinical trial has demonstrated that the drug causes asthma.

More

Cancer cells slurp up Fructose

Pancreatic tumor cells use fructose to divide and proliferate, U.S. researchers said on Monday in a study that challenges the common wisdom that all sugars are the same.Tumor cells fed both glucose and fructose used the two sugars in two different ways, the team at the University of California Los Angeles found.

They said their finding, published in the journal Cancer Research, may help explain other studies that have linked fructose intake with pancreatic cancer, one of the deadliest cancer types. “These findings show that cancer cells can readily metabolize fructose to increase proliferation,” Dr. Anthony Heaney of UCLA's Jonsson Cancer Center and colleagues wrote. “They have major significance for cancer patients given dietary refined fructose consumption, and indicate that efforts to reduce refined fructose intake or inhibit fructose-mediated actions may disrupt cancer growth.”

Americans take in large amounts of fructose, mainly in high fructose corn syrup, a mix of fructose and glucose that is used in soft drinks, bread and a range of other foods. Politicians, regulators, health experts and the industry have debated whether high fructose corn syrup and other ingredients have been helping make Americans fatter and less healthy.

Too much sugar of any kind not only adds pounds, but is also a key culprit in diabetes, heart disease and stroke, according to the American Heart Association. Several states, including New York and California, have weighed a tax on sweetened soft drinks to defray the cost of treating obesity-related diseases such as heart disease, diabetes and cancer. The American Beverage Association, whose members include Coca-Cola (KO.N) and Kraft Foods (KFT.N) have strongly, and successfully, opposed efforts to tax soda. The industry has also argued that sugar is sugar.

Heaney said his team found otherwise. They grew pancreatic cancer cells in lab dishes and fed them both glucose and fructose. Tumor cells thrive on sugar but they used the fructose to proliferate. “Importantly, fructose and glucose metabolism are quite different,” Heaney's team wrote. “I think this paper has a lot of public health implications. Hopefully, at the federal level there will be some effort to step back on the amount of high fructose corn syrup in our diets,” Heaney said in a statement.

Now the team hopes to develop a drug that might stop tumor cells from making use of fructose.

U.S. consumption of high fructose corn syrup went up 1,000 percent between 1970 and 1990, researchers reported in 2004 in the American Journal of Clinical Nutrition.

More

Anti-Cancer Effects of Broccoli

Light has been cast on the interaction between broccoli consumption and reduced prostate cancer risk. Researchers writing in BioMed Central's open access journal Molecular Cancer have found that sulforaphane, a chemical found in broccoli, interacts with cells lacking a gene called PTEN to reduce the chances of prostate cancer developing.

Richard Mithen, from the Institute of Food Research, an institute of BBSRC, worked with a team of researchers on Norwich Research Park, UK, to carry out a series of experiments in human prostate tissue and mouse models of prostate cancer to investigate the interactions between expression of the PTEN gene and the anti-cancer activity of sulforaphane. He said, “PTEN is a tumour suppressor gene, the deletion or inactivation of which can initiate prostate carcinogenesis, and enhance the probability of cancer progression. We've shown here that sulforaphane has different effects depending on whether the PTEN gene is present”.

The research team found that in cells which express PTEN, dietary intervention with SF has no effect on the development of cancer. In cells that don't express the gene, however, sulforaphane causes them to become less competitive, providing an explanation of how consuming broccoli can reduce the risk of prostate cancer incidence and progression. According to Mithen, “This also suggests potential therapeutic applications of sulforaphane and related compounds”.

More

Anxiety and Depression with a Gluten Free Diet

The team set out to examine levels of depression and anxiety between adults with celiac disease following a gluten-free diet and in control subjects drawn from the general population.

For their study, the team used the Hospital Anxiety and Depression Scale to measure levels of anxiety, depression, and likely anxiety or depressive disorder, in 441 adult patients with celiac disease recruited by the German Celiac Society. They then conducted the same assessments on 235 comparable patients with inflammatory bowel disease (IBD), either in remission or with slight disease activity. They did the same for the cross-sample control group of 441 adults from the general population.

The team used regression analysis to test possible demographic and disease-related predictors of anxiety and depression in celiac disease. Demographic predictors included age, sex, social class, and family status. Disease-related predictors included Latency to diagnosis, duration of GFD, compliance with GFD, thyroid disease.

The team found that female gender (P = 0.01) was the main predictor (R(2) = 0.07) of anxiety levels in patients with celiac disease. Female patients had a higher risk for a probable anxiety disorder (OR = 3.6, 95% CI: 1.3-9.4, P = 0.01) Patients who lived alone (OR = 0.5, 95% CI: 0.2-0.9, P = 0.05) enjoyed a lower risk of anxiety disorder. None of the demographic and medical variables for which the team screened predicted either depression levels or risk for a probable depressive disorders.

Patients with celiac disease showed anxiety levels of 6.6 +/- 3.4, and those with IBD, anxiety levels of 6.9 +/- 3.7, both higher than the general population's level of 4.6 +/- 3.3 – (both P < 0.001). Depression levels were similar for people with celiac disease (4.2 +/- 3.4), IBD (4.6 +/- 3.4) and the general population (4.2 +/- 3.8) (P = 0.3). Rates of likely anxiety disorders in people with celiac disease were 16.8%, and 14.0% for IBD, both higher than the rates of 5.7% in the general population (P < 0.001). All three groups showed similar rates of probable depressive disorder (P = 0.1).

Their results provide strong indications that adult women with celiac disease on a gluten-free diet suffer higher rates of anxiety than persons of the general population. They encourage clinicians to provide anxiety screens for adult women with celiac disease on a gluten-free diet.

More

Cheese improves immune response of elderly

To tackle immunosenescene the team targeted the gastrointestinal tract, which is the main entry for bacteria cells into the body through food and drink and is also the site where 70% of vital immunoglobulin cells are created.

The team asked volunteers aged between 72 and 103, all of which lived in the same care home, to eat one slice of either placebo or probiotic Gouda cheese with their breakfast for four weeks. Blood tests where then carried out to discover the effect of probiotic bacteria contained within the cheese on the immune system.

The results revealed a clear enhancement of natural and acquired immunity through the activation of NK blood cells and an increase in phagocytic activity.

“The aim of our study was to see if specific probiotic bacteria in cheese would have immune enhancing effects on healthy older individuals in a nursing home setting,” concluded Ibrahim. “We have demonstrated that the regular intake of probiotic cheese can help to boost the immune system and that including it in a regular diet may help to improve an elderly person's immune response to external challenges.

More