Vitamin K appears to slow development of insulin resistance in elderly men
A drug based on a chemical found in garlic can treat diabetes types I and II when taken as a tablet, a study in the new Royal Society of Chemistry journal Metallomics says. When Hiromu Sakurai and colleagues from the Suzuka University of Medical Science, Japan, gave the drug orally to type I diabetic mice,
Full Post: Garlic drug treats diabetes
Vitamin K slowed the development of insulin resistance in elderly men in a study of 355 non-diabetic men and women ages 60 to 80 who completed a three-year clinical trial at the Jean Mayer Human Nutrition Research Center on Aging at Tufts University (USDA HNRCA).
“Men who received vitamin K supplementation had less progression in their insulin resistance by the end of the clinical trial,” said Sarah Booth, senior author and director of the Vitamin K Laboratory at the USDA HNRCA. “Conversely, we saw progression in insulin resistance in women who received vitamin K supplementation, and in the men or women who were not given vitamin K supplements.”
Among those given vitamin K, both men and women took daily multivitamins containing 500 micrograms of vitamin K, five times the Adequate Intake (AI) recommended by the Institute of Medicine’s Food and Nutrition Board, with instructions to maintain normal diets without any additional supplementation. They also received a calcium and vitamin D supplement. Men and women in the control group received no vitamin K supplementation but did receive the multivitamin and the calcium and vitamin D supplement. For the present study, insulin resistance was assessed by the homeostasis model (HOMA-IR). Additionally, participants’ blood glucose and blood insulin levels were measured following a minimum 10-hour fast. In addition to improved insulin resistance, the supplemented men had lower blood insulin levels compared to the unsupplemented men at the conclusion of the study.
Insulin is a hormone which plays a role in transporting sugar into cells so it can be converted into energy. A pre-cursor to diabetes, insulin resistance occurs when the body cannot use insulin properly, causing glucose to build up in the blood. People who are obese or overweight are prone to insulin resistance because excess fat can interfere with insulin function.
Writing in the November issue of Diabetes Care , the authors speculate that weight might explain why only the vitamin K supplemented men improved their insulin resistance. “In our study, there was a higher prevalence of obese or overweight women in the vitamin K supplementation group compared to the male supplementation group,” Booth said. “Vitamin K is stored in fat tissue. If there is excess fat, vitamin K may not be readily available to cells that require it to process glucose.”
Because there are few studies of vitamin K and insulin resistance, the authors encourage further investigation of their findings and alternative study designs. “The original purpose of the present study was to assess the effect of vitamin K1, or phylloquinone, supplementation on changes in bone mineral density and vascular calcification,” Booth said. “For instance, there is a way to achieve a more direct measure of insulin secretion than HOMA-IR. Also, our study is limited to caucasian adults. We acknowledge our findings may not apply to the general population.”
Although vitamin K supplements were used for the study, the authors say the study dosage is attainable by consuming a healthy diet. Foods considered good sources of vitamin K include brussels sprouts, broccoli, and dark, leafy greens, such as spinach and collards.
Vitamin D is quickly becoming the “it” nutrient with health benefits for diseases, including cancer, osteoporosis, heart disease and now diabetes. A recent review article published by researchers from Loyola University Chicago Marcella Niehoff School of Nursing concluded that adequate intake of vitamin D may prevent or delay the onset of diabetes and reduce complications
Full Post: Vitamin D offers widespread benefits for health
Women who took beta carotene or vitamin C or E or a combination of the supplements had a similar risk of cancer as women who did not take the supplements, according to data from a randomized controlled trial in the December 30 online issue of the Journal of the National Cancer Institute. Epidemiological studies
Full Post: Vitamins C and E and beta carotene again fail to reduce cancer risk in randomized controlled trial
Vitamin D deficiency - which is traditionally associated with bone and muscle weakness - may also increase the risk of cardiovascular disease (CVD). A growing body of evidence links low 25-hydroxyvitamin D levels to common CVD risk factors such as hypertension, obesity and diabetes, as well as major cardiovascular events including stroke and congestive heart
Full Post: Vitamin D deficiency could lead to heart problems
Taking calcium and vitamin D supplements does not reduce breast cancer incidence in postmenopausal women, according to data from a randomized, doubled-blind, placebo-controlled trial published online November 11 in the Journal of the National Cancer Institute. Several observational and preclinical studies have suggested that vitamin D supplements may reduce breast cancer risk, but results have
Full Post: Taking calcium and vitamin D supplements does not reduce breast cancer risk
A new randomized, prospective trial has shown that orlistat, a commonly prescribed inhibitor of fat absorption, does not help patients with fatty liver disease (FLD) lose weight, nor does it improve their liver enzymes or insulin resistance. These findings are in the January issue of Hepatology, a journal published by John Wiley & Sons on
Full Post: Fatty liver disease medication may have no effect