People who weigh more have lower circulating levels of Vitamin D according to recent research conducted at the Rikshospitalet-Radiumhospitalet Medical Center in Oslo, Norway and published in the Journal of Nutrition. Lead researcher, Zoya Lagunova, MD and her colleagues measured the serum levels of Vitamin D and 1,25(OH)2D in 1,779 patients at a Medical and Metabolic Lifestyle Management Clinic in Oslo, Norway. The associations among 1,25(OH)(2)D, serum 25-hydroxyvitamin D [25(OH)D], and body composition were analyzed. Lagunova noted that generally people with higher BMI had lower levels of Vitamin D. Age, season, and gender were also found to influence serum 1,25(OH)(2)D.
Vitamin D is not a true vitamin, but rather a vitamin-steroid thought to play a key role in the prevention of cancer, cardiovascular disease, diabetes, multiple sclerosis and other diseases. It is likely not coincidental that obesity is also a risk factor for many of these diseases. Vitamin D is vital to the regulation of calcium. Studies have shown that calcium deficiency increases the production of synthase, an enzyme that converts calories into fat. It has been shown that calcium deficiency can increase synthase production by up to 500 percent. Vitamin D has also been shown to play a role in the regulation of blood sugar levels; proper blood sugar regulation is vital to the maintenance of a healthy weight. Vitamin D is produced from sunlight and converted into various metabolites. It is stored in fat tissue. According to Lagunova, obese people may take in as much Vitamin D as other people; however, because it is stored in fat it may be less available. This may result in lower circulating levels of Vitamin D.
A previous study conducted by Shalamar Sibley, MD, MPH, an assistant professor of medicine at the University of Minnesota, showed that subjects who have higher levels of Vitamin D at the start of a weight loss diet lose more weight than those with lower levels. The study measured Vitamin D levels of 38 overweight men and women both before and after following an 11-week calorie-restricted diet. Vitamin D levels at the start of diet was an accurate predictor of weight loss…those with higher levels of Vitamin D lost more weight. It was found that for every nanogram increase in Vitamin D precursor, there was an 1/2 pound increase in weight loss.
Seventy-five percent or more of Americans, teenage and older, are Vitamin D deficient according to a recent study published in the Archives of Internal Medicine. According to the Gallup-Healthways Well-Being Index, 26.5% of American are obese. More research needs to be conducted into the exact role Vitamin D plays in obesity and weight loss and the possibility of increased Vitamin D consumption (through the form of supplementation and/or increased sun exposure) being a key factor to achieving a healthy weight.
Metabolic syndrome is a cluster of risk factors which can result in heart disease and diabetes. Researchers have now found that poor diet and lack of exercise that lead to an imbalance in metabolism may also increase a child's risk of developing asthma.
Dr. Giovanni Piedimonte and researchers from West Virginia University School of Medicine analyzed data from nearly 18,000 children aged 4 to 12 years who were taking part in the Coronary Artery Risk Detection in Appalachian Communities (CARDIAC) project. Factors considered included triglyceride levels and evidence of acanthosis nigricans, which are raised patches of brown skin that are often biomarkers for insulin resistance.
The team also considered body mass index or BMI, and almost 21% of the children were considered obese. Fourteen percent of the children had asthma.
The researchers found that asthma prevalence among the children was strongly associated with certain symptoms of metabolic syndrome including dyslipidemia and abnormal glucose metabolism, but not weight status. Although those who were obese were more likely to have asthma, even children of a healthy weight who had imbalanced metabolism were at increased risk.
Certain metabolic factors participate in the asthma disease process by contributing to inflammation of the airways in the lungs and hyperreactivity (contraction of smooth muscle in the bronchial walls), says Dr. Piedimonte. He says that strict monitoring and control of triglyceride and glucose levels early in life may play a role in the management of chronic asthma in children.
Dr. Piedimonte would like to see the findings used as further support for universal lipid screening in children. “The rationale is that by using selective screening, we would have missed over a third of children with significant genetic dyslipidemia,” he said.
Both poor diet – one lacking in antioxidants but high in fat – and inadequate exercise play a role in the metabolic syndrome, a group of risk factors that increase the risk for coronary artery disease, stroke, and type 2 diabetes. The goal of treatment is often weight loss (if overweight), a minimum of 30 minutes of daily moderate intensity exercise, and a lowering of cholesterol, blood pressure and blood sugar through diet or medication.
Cottrell L, et al “Metabolic abnormalities in children with asthma” Am J Respir Crit Care Med 2010; DOI: 10.1164/rccm.201004-0603OC.
The team looked at how NK cells (natural killer cells – a type of immune cell) reacted to Helicobacter pylori. These cells are an important part of the immune system as they can both recognise and kill cells that are infected by viruses and bacteria as well as tumour cells.
“We found that a special type of NK cells was active against the stomach ulcer bacterium,” says Åsa Lindgren. “These NK cells produced cytokines, which are the immune system's signal substances and act as a defence against the intruder.”
The researchers' results suggest that NK cells can play an important role in the immune defence against Helicobacter pylori. Previous research has also shown that a high proportion of NK cells in tumour tissue has contributed to a better prognosis and longer survival for patients with stomach cancer, as these cells help to eliminate the tumour cells.
The researchers therefore believe that activation of the NK cells can play a key role in stopping tumours from developing, and that reduced NK-cell activity can increase the risk of cancer developing. Åsa Lindgren hopes that these findings can be used to develop new ways of diagnosing and treating stomach cancer.
“This would make it possible to diagnose stomach cancer at an early stage, which, in turn, could mean a better prognosis for the patients.”
When it comes to buying fruits and vegetables, many factors play a role in which types consumers choose, including nutritional value. Are there significant differences among fresh, frozen, canned or dried? The American Dietetic Association says no matter what form they take, fruits and vegetables are good-for-you foods that can be enjoyed at any time.