In The News: April 2013

The results of a meta-analysis published in the Journal of Nutrition reveal an association between diets that include higher amounts of magnesium with lower blood levels of fasting glucose and insulin.*

Researchers sought to determine the influence of genetic variations associated with glycemic traits or magnesium metabolism on fasting glucose and insulin levels, which are elevated in metabolic syndrome and type II diabetes. They analyzed data from up to 52,684 nondiabetic men and women who participated in 15 studies. Participants were genotyped for up to 25 single nucleotide polymorphisms related to fasting glucose, insulin, or magnesium.

Reductions in both fasting glucose and fasting insulin were observed in association with increased magnesium.

Editor’s Note:  The authors concluded that, “Their results indicate that higher dietary magnesium intake is inversely associated with fasting glucose and fasting insulin in individuals free of diabetes.”

A review published online recently in the journal BioFactors documents a benefit for curcumin, a compound that occurs in the spice turmeric, in extending the life of several species.*

In a study involving the roundworm C. elegans, growth media containing a low concentration of curcumin increased mean (average) life span by 39% and maximum life span by 21.4%.  

In a study with fruit flies, which generally survive an average of 64 days, an increase of mean life span to 80 days occurred in curcumin-fed flies. Another study involving two strains of flies found varying effects of curcumin in male and female flies, with females of one strain and males of another strain experiencing an extension in life span. A third fly study also revealed a variation in male and female response to curcumin, although the compound was shown to extend life in both genders. 

An article published in the journal Cancer Letters reveals a potent effect for grape seed extract against colorectal cancer in experiments involving cultured cancer cells. The findings indicate a beneficial effect for grape seed extract that increases with higher stage cancer.*

Molly Derry of the University of Colorado and her associates tested the effect of grape seed extract in colorectal cancer cell lines in various stages of disease. They observed an increase in several of grape seed extract’s anticancer mechanisms in association with increasing cancer stage. The effect is in sharp contrast with that of chemotherapy, which becomes less potent in association with increased metastatic potential. 

The discovery is of significance in view of the increased prevalence of colorectal cancer in Western societies, coupled with the fact that many of those diagnosed are at an advanced stage of cancer. 

The Journal of the American College of Cardiology published the finding of Danish researchers of reductions in glucose tolerance and coenzyme Q10 levels in men treated with simvastatin, one of several statin drugs commonly prescribed to lower cholesterol.* 

The current study included ten individuals treated for high cholesterol with simvastatin for at least one year and ten healthy control subjects. Participants underwent oral glucose tolerance tests, muscle biopsies, and blood testing for numerous factors. Four of those in the simvastatin group reported muscle pain, compared to none of the controls. Among simvastatin-treated subjects, glucose levels were significantly higher during two-hour oral glucose tolerance testing in comparison with untreated controls. When tissue biopsy results were compared, CoQ10 and the antioxidant enzymes catalase, manganese superoxide dismutase, and glutathione peroxidase were lower in those treated with simvastatin (Zocor®). 

Editor’s Note:  While statin drugs are of benefit to millions of people at risk for cardiovascular events, their effect on coenzyme Q10, an important mitochondrial cofactor, has not been well publicized in mainstream medical media. (Mitochondria are the cells’ energy-producing organelles.)

An article in a recent issue of Circulation reported the finding of a decrease in the risk of myocardial infarction in women with a high intake of anthocyanins—flavonoids that occur in significant amounts in such foods as blueberries and strawberries.* 

The study included 93,600 women between the ages of 25 and 42 upon enrollment in the Nurses’ Health Study II in 1989. Dietary questionnaires completed every four years beginning in 1991 provided information on the intake of anthocyanins. The participants were followed for 18 years, during which 405 heart attacks occurred.

Among women whose intake of anthocyanins was among the top one-fifth of subjects, there was a 32% lower risk of heart attack in comparison with those whose intake was among the lowest fifth.

In the medical journal Phytotherapy Research, two researchers, one from the Nirmala Medical Centre in India and the other from Baylor Research Institute and the Sammons Cancer Center in Texas, published their work on curcumin.* They showed that curcumin is more effective than the common anti-inflammatory medication diclofenac for the pain associated with mild, active rheumatoid arthritis.

In the study, rheumatoid arthritis patients taking curcumin for eight weeks had a 44% reduction in pain symptoms, while those taking diclofenac had a 42% reduction. It may not seem like there is a big difference between curcumin and diclofenac, but the difference was significant.

Interestingly, the curcumin group also had a greater reduction in overall inflammation (rheumatoid arthritis may have slightly improved) compared to the diclofenac group. Most importantly, there were no adverse events with curcumin.

In an article published in Nutrition Journal, researchers in China report a beneficial effect for supplementation with calcium and vitamin D in reducing the body fat of overweight and obese college students.*

The trial included 43 men and women with a body mass index (BMI) of 24 or higher.  Participants were randomized to receive an energy restricted diet supplemented with 600 mg of elemental calcium and 125 IU vitamin D3, or an unsupplemented diet for 12 weeks. 

While the amount of weight lost by both groups was similar, a significantly greater reduction in fat mass loss and fat percentage occurred in the participants that received calcium in comparison with unsupplemented subjects. Men and women who received calcium and vitamin D experienced a 53.6% greater decrease in fat mass loss than the control subjects, and had a greater reduction in visceral fat mass and fat area.