Vitamin D is necessary to trigger T cells – the immune system’s killer cells – into action, and insufficient levels of the vitamin mean the cells remain dormant and inactive, according to findings published in Nature Immunology.

“Scientists have known for a long time that vitamin D is important for calcium absorption and the vitamin has also been implicated in diseases such as cancer and multiple sclerosis, but what we didn’t realize is how crucial vitamin D is for actually activating the immune system – which we know now,” said scientists from the University of Copenhagen.

The study adds to an ever growing body of science supporting the benefits of maintaining healthy vitamin D levels.

In adults, it is said vitamin D deficiency may precipitate or exacerbate osteopenia, osteoporosis, muscle weakness, fractures, common cancers, autoimmune diseases, infectious diseases and cardiovascular diseases. There is also some evidence that the vitamin may reduce the incidence of several types of cancer and type-1 diabetes.

According to the Copenhagen-based researchers, activated T cells can become one of two types of immune cell: Killer cells that attack and destroy all cells carrying traces of a foreign pathogen; or helper cells that assist the immune system in acquiring “memory”. If the cell is not activated it is known as a naïve cell.

For their research, researchers led by Professor Carsten Geisler examined the expression of a specific molecule (PLC-gamma1) that would enable the cell to deliver an antigen specific response. They found that naïve T cells had very low expression of PLC-gamma1 and that triggering of the T cell led to a 75-fold increase in PLC-gamma1 expression. Their data also showed that induction of PLC-gamma1 was dependent on vitamin D.

“When a T cell is exposed to a foreign pathogen, it extends a signaling device or ‘antenna’ known as a vitamin D receptor, with which it searches for vitamin D,” explained Prof Geisler. “This means that the T cell must have vitamin D or activation of the cell will cease. If the T cells cannot find enough vitamin D in the blood, they won’t even begin to mobilize.”

The findings could help us combat infectious diseases and global epidemics, said Prof Geisler. Indeed, last year the Public Health Agency of Canada (PHAC) confirmed that it will be investigating the role of vitamin D in protection against swine flu.

Author: Stephen Daniells
Source: NutraIngredients.com

U.S. researchers analyzed data from 39,765 men in the Health Professionals Follow-up Study and 157,463 women in the Nurses’ Health Study I and II. None of the participants had diabetes, heart disease or cancer at the start of the studies. Their consumption of brown and white rice, as well as other foods, was assessed every two to four years.

During 3.3 million person-years of follow-up, there were 10,507 incidents of type 2 diabetes. After adjusting for a number of dietary and lifestyle risk factors, the researchers found that people who ate five or more servings per week of white rice were 17 percent more likely to develop type 2 diabetes than those who ate less than one serving of white rice per month.

In contrast, people who ate two or more servings of brown rice per week were 11 percent less likely to develop type 2 diabetes than those who ate less than one serving of brown rice per month, the study authors reported.

“We estimated that replacing 50 grams/day intake of white rice with the same amount of brown rice was associated with a 16 percent lower risk of type 2 diabetes, whereas the same replacement with whole grains as a group was associated with a 36 percent lower diabetes risk,” wrote Dr. Qi Sun, of Harvard School of Public Health in Boston, and colleagues.

The study was to be presented Wednesday at the American Heart Association’s Nutrition, Physical Activity and Metabolism Conference in San Francisco.

Source: HealthDay News via Yahoo News
Original Date: March 3, 2010

GlaxoSmithKline will stop making and marketing Super Poligrip Original, Ultra Fresh and Extra Care products in the U.S. The company plans to reformulate the creams without zinc.

The company, based in London, reported more than $520 million in denture adhesive sales last year.

It stressed that the products are safe when used as directed, but that some people use extra cream to correct ill-fitting dentures.

Glaxo’s voluntary action comes as hundreds of lawsuits are poised to go to trial, alleging Poligrip caused nerve damage, leading to a loss of balance, loss of sensation in the hands and feet, and leaving some patients paralyzed.

“They made the right decision in the sense that it’s going to prevent the crippling of more people,” said attorney Andy Alonso of Parker Waichman Alonso LLP. “But it’s too late for many of my clients.”

Alonso represents more than a hundred users of denture cream in Miami federal court, where several hundred lawsuits are being consolidated. The plaintiffs say the makers of zinc-based creams failed to warn consumers about potential risks.

Alonso estimates about 30 million people in the U.S. wear dentures and use products like Poligrip.

There are currently 75 denture cream cases consolidated before Miami U.S. District Judge Cecilia M. Altonaga, who will decide whether to choose a few for trial that would act as bellwethers for the rest, said plaintiffs’ attorney Scott Weinstein. The Glaxo decision would have limited impact due to rules against using a company’s actions to fix a problem in suits claiming previous damages, he said.

Altonaga’s next hearing is set for March 23.

One of the lawsuit plaintiffs, 62-year-old Ronald Beaver of Tamarac, Fla., used PoliGrip for years before he began feeling weak and developed a blood disorder four years ago. He’s now able to work only two days a week at his moving company job and feels “run down” much of the time.

Told of GlaxoSmithKline’s decision on zinc products, Beaver said he was “shocked” because the company had consistently denied any problems in the past.

“It’s like a complete admission. They went from outright denial to a complete admission,” Beaver said.

Lawyers suing Glaxo said the company’s decision will put pressure on other makers of zinc-containing denture cream, most notably Procter & Gamble, which makes Fixodent.

A spokeswoman for Cincinnati-based P&G said the company has no plans to reformulate its product.

“The levels of zinc in Fixodent are approximately half of what’s used in Super Poligrip,” said Michelle Vaeth. She added that the amount of zinc in Fixodent is equal to that found in a hamburger.

Both Glaxo and P&G market zinc-free alternatives to their products.

Federal health experts recommend 8 milligrams of zinc per day for women and 11 milligrams for men. The right amount of zinc helps the body fight off illnesses and also promotes cell growth.

Attorney Ed Blizzard, who represents several dozen plaintiffs, said Poligrip contains 38 milligrams of zinc per ounce.

Although one tube is meant to last 8 to 10 weeks, Blizzard says some of his patients were using a tube of Poligrip a week, giving them about 45 times the recommended dose of zinc.

Blizzard is encouraged by Glaxo’s decision to phase out the product, but he says it’s no indication the company plans to settle the lawsuits.

Denture creams containing zinc were first approved by the FDA more than 15 years ago, and the agency has never issued a safety warning on the products, according to industry group Consumer Healthcare Products Association.

Zinc is believed to help with adhesion. But in 2008 researchers at the University of Texas Southwestern Medical Center in Dallas described a possible link between denture cream zinc and nerve damage.

The researchers noted that excessive zinc can purge the body of copper, a chemical needed for normal brain and nervous system function.

A copper deficiency can cause anemia, as well as weakness and numbness in arms and legs; difficulty walking and loss of balance; and eventually permanent paralysis.

“Our typical Super Poligrip and Fixodent client uses a wheelchair, walker or cane for mobility and many of them have hands so spastic that they resemble claws,” said Eric Chaffin, a partner with Chaffin Luhana, which represents several dozen patients.

Glaxo and P&G only began disclosing the zinc in their products after the University of Texas’ findings were published in a medical journal.

Author: Matthew Perrone and Curt Anderson
Source: YahooNews / Associated Press
Original Date: Feb 18, 2010

Results of a 26-week randomized, double-blind, placebo-controlled intervention study with 87 women found that multivitamins and minerals were associated with significantly lower body weight, body mass index, and fat mass

Levels of total cholesterol and LDL-cholesterol were also significantly reduced, while HDL-cholesterol were increased, according to findings published in the International Journal of Obesity.

Obesity rates have skyrocketed in the US in recent years – 15 per cent of the population was obese in 1980, compared to 34 per cent today, according to figures from the Center for Disease Control and Prevention.

If other clinical trials in other populations support the findings, it could see multivitamins and minerals touted for their weight management potential.

Multivitamin use

According to a National Institutes of Health (NIH) State-of-the-Science Panel, half of the American population routinely use dietary supplements, with their annual spend estimated at over $20 billion.

Recent results of the National Health and Nutrition Examination Survey showed that 35 per cent of the US adult population regularly consumes one or more types of multivitamin product (Am. J. Epidemiol., 2004, Vol. 160, Pages 339-349).

Study details

Ninety-six obese women aged between 18 and 55 were recruited to participate in the study, with 87 completing the 26 weeks of intervention. Women were randomly assigned to one of three groups: One received a multivitamin and mineral supplement; the second received a calcium supplement (162 mg per day); and the third received an identical placebo.

Led by Professor CH Sun from the Department of Nutrition and Food Hygiene at Harbin Medical University, the Chinese researchers report that the multivitamin and mineral group lost an average of 3.6 kg of body weight, compared to 0.9 kg and 0.2 kg for the calcium and placebo groups, respectively.

In addition, significant reductions in BMI and waist circumference were observed in the multivitamin and mineral group, while the changes in the other groups were not significant.

“To our knowledge, this study is the first to evaluate the effects of multivitamin and mineral supplementation on lipid profile in obese subjects,” wrote the researchers.

Calcium and dairy

On the other hand, the calcium group only experienced cholesterol improvements, with HDL levels increasing and LDL decreasing, compared with the placebo group.

This last point taps into a different debate, which has focussed on the potential of dairy to aid weight loss.

A relationship between dairy intake and weight reduction has been recorded in numerous studies, and dairy industries in Europe and the US have been promoting milk-based products for consumers who want to slim for some time. The subject, however, remains controversial.

There are even splits within the dairy camp, with some arguing that calcium and vitamin D are the active nutrients behind the effects. One of the lead researchers in this are, Dr Michael Zemel from the University of Tennessee, has previously said that dairy can help reduce body fat and that calcium only accounts for about 40 per cent of the effect.

Source: NutraIngredients.com
Author: Stephen Daniells
Original Date: Feb 25th, 2010

According to findings published in Nutrition Research, addition of milk of any kind reduced the antioxidant potential of black tea by between 7 and 25 per cent than unmilked tea.

However, addition of skimmed milk decreased the total antioxidant capacity of black tea much more than whole or semi-skimmed milk, report Lisa Ryan and Sébastien Petit from the Functional Food Center at Oxford Brookes University.

The reduction in the antioxidant activity of tea, as measured by the FRAP assay, was reported to be a linked to the levels of theaflavins and thearubigins that will affect the total antioxidant capacity of black tea.

“Although the addition of milk may not inhibit the catechin or quercetin concentrations, it may affect other antioxidant components such as the theaflavins and thearubigins that will affect the total antioxidant capacity of black tea,” wrote Ryan and Petit.

Green versus black

The majority of science on tea has looked at green tea, with benefits reported for reducing the risk of Alzheimer’s and certain cancers, improving cardiovascular and oral health, as well as aiding in weight management.

Green tea contains between 30 and 40 per cent of water-extractable polyphenols, while black tea (green tea that has been oxidized by fermentation) contains between 3 and 10 per cent. Considering that the British consume between three and four cups of black tea a day, often with milk (and the rest of the world averages between one and two cups a day), the findings could have public health implications, said the Oxford-based researchers.

“From a public health perspective, tea is rich in antioxidants and may be an important contributor to an individual’s overall antioxidant status,” they wrote.

Contrasting science

Previous studies have reported somewhat contradictory data. A study from 2007 by German scientists at the Charite Hospital in Berlin found that drinking tea with milk may block the cardiovascular benefits of the catechins.

Writing in the European Heart Journal (2007, Vol. 28, pp. 219-223), the researchers found that while tea increased the artery’s ability to relax and expand to accommodate increased blood flow compared to water, this effect was blocked when milk was added to the beverage.

The new research depends our understanding of the potential health benefits of the beverage may be related to the fat content of the milks used, and that not all milk affects the bioavailability of tea compounds equally.

Ryan and Petit analysed the antioxidant capacity of five brands of black with different volumes of whole milk, semiskimmed, and skimmed milk.

Their results showed that adding of 10, 15, and 20 mL of whole, semiskimmed, and skimmed cow’s milk decreased the total antioxidant capacity, but that skimmed milk decreased it the most.

“We accept the hypothesis that different volumes of bovine milk and milk of varying fat content affect the total antioxidant capacity of tea,” wrote Ryan and Petit.

“The degree to which the addition of milk reduces the antioxidant capacity of black tea depends on the amount added and the fat content of the milk,” they added.

And what about coffee?

A recent study by food giant Nestlé reported that adding milk to instant coffee had no effect on the uptake of coffee’s antioxidants, including caffeic acid, ferulic acid, and isoferulic acid.

According to findings of a study with nine people published in The Journal of Nutrition, the uptake of caffeic and ferulic acids was lower, however, when coffee was made with non-dairy creamer and sugar.

Source: NutraIngredients.com
Author: Stephen Daniells
Original Date: March 2, 2010