Increased Magnesium Intake Linked to Lower Risk of Type 2 Diabetes

Type 2 diabetes prevalence is rising in Asian countries. New research indicates that increased magnesium intake may reduce the risk of type 2 diabetes in Japanese adults.

A new study published in the Journal of the American College of Nutrition reports a correlation between higher magnesium intake and a reduced rate of type 2 diabetes. Low magnesium intakes have previously been linked to insulin resistance and impaired glucose utilization.

Researchers evaluated data from 17,592 men and women aged 40 to 79 who took part in the Japan Collaborative Cohort Study for Evaluation of Cancer Risk established between 1988 and 1990. Dietary magnesium was calculated using a validated questionnaire, and incidence of diabetes was defined by self-report of physician diagnosis.

At the five year follow-up, 459 new cases of diabetes were reported. Dietary intake of magnesium was inversely associated with age, body mass index (BMI), and diabetes incidence in both sexes.

After making adjustments for cardiovascular risk factors, participants whose intake of magnesium was among the top 25 percent had a 36 percent lower adjusted risk of developing diabetes.

The incidence of type 2 diabetes is increasing in Asian countries, and this is the first study to examine the association between magnesium intake and the risk of diabetes in adults living in Japan. The results of this study are important for the development of potential health policies to help prevent and control this increasingly common degenerative disease.

Kyoko K, et al. Magnesium Intake and Risk of Self-Reported Type 2 Diabetes among Japanese. 2010. Journal of the American College of Nutrition, Vol. 29, No. 2, 99-106.

Vitamin D Levels Linked to Healthy Lung Function

Vitamin D may play a role in keeping our lungs healthy, with higher concentrations of vitamin D resulting in positive effects on lung function and health.

Low concentrations of vitamin D have been associated with a number of diseases. Research out of New Zealand indicates that serum concentrations of vitamin D may also influence pulmonary (lung) function.

In a study published in the journal Chest, original analysis was performed on data from 14,091 adult subjects (all participants in the U.S. National Health and Nutrition Examination Survey conducted between 1988 and 1994). Lung function was measured in two ways: by the volume of air that could be forcibly blown out in total (forced vital capacity, or FVC), and the volume blown out in one second (forced expiratory volume, or FEV1). Vitamin D was measured using serum 25-hydroxyvitamin D, a standard indicator of vitamin D levels.

After adjusting for age, gender, height, body mass index, ethnicity, and smoking history, the difference in lung function between the groups with the highest and lowest vitamin D intake was substantial in both the FVC and FEV1 tests (172 mL and 126 mL respectively, p <0.0001). Further adjustment for physical activity, vitamin D supplementation, milk intake, and serum antioxidant status revealed additional strong correlation between the highest and lowest intake groups (142 mL (FVC) and 106 mL (FEV1), p < 0.0001).

Although further studies are necessary to determine whether vitamin D supplementation may be beneficial in cases of chronic respiratory disease, this study has shown that vitamin D may have a positive influence on pulmonary health, with greater levels of vitamin D associated with more positive benefits.

Chest 2005 Dec;128(6):3792-8

Vitamin D Deficiency Associated with Cardiovascular Disease Prevalence

In a large sample of U.S. adults, new research indicates that vitamin D deficiency is associated with an increased prevalence of cardiovascular disease.

Inadequate vitamin D levels are known to be associated with certain cardiovascular disease (CVD) risk factors, but until recently the association between vitamin D levels and the prevalence of CVD had not been comprehensively examined in the general U.S. population.

In a recent study published in Atherosclerosis, researchers examined data from the Third National Health and Nutrition Examination Survey (NHANES), a population-based sample of more than 16,000 U.S. adults.

In the total survey population, 1,308 subjects had some form of CVD. Using the standard definition of vitamin D deficiency (a serum level below 20 ng/mL), participants with CVD had a higher incidence of vitamin D deficiency (29.3%) than those without CVD (21.4%). After adjusting for age, gender, race/ethnicity, season of measurement, physical activity, body mass index, smoking status, hypertension, diabetes, elevated cholesterol, chronic kidney disease, and vitamin D use, the researchers showed that subjects deficient in vitamin D had a 20% increased risk of CVD.

The results of this analysis indicate a significant relationship between vitamin D deficiency and CVD prevalence in a large, highly representative sample of the U.S. adult population.

Atherosclerosis 2009 Jul; 205(1):255-60.

New Diabetes Projections "Paint Sobering Picture of the Future"

Without widespread intervention, one in three American adults could have type 2 diabetes by the year 2050.

Type 2 diabetes is a chronic health condition that develops when the body becomes resistant to insulin, a hormone that regulates carbohydrate and fat metabolism. The exact mechanism by which type 2 diabetes occurs is unknown, but a number of correlating risk factors - particularly obesity and physical inactivity - are well-established. Unfortunately, the number of individuals with type 2 diabetes has increased sharply in recent years, with an estimated $174 billion cost to the United States in 2007 alone.

A number of papers have attempted to project type 2 diabetes prevalence 5, 10, and 20+ years into the future. Unfortunately, most of these projections have relied on weak or outdated metrics, including old census data, static mortality rates, and overly simple estimations of diabetes incidence. A recent paper from researchers at the National Center for Chronic Disease Prevention and Health Promotion hoped to overcome these weaknesses by utilizing recent census data and a matrix of factors derived from an extensive literature review.

The researchers describe their results as "a sobering picture of the future growth of diabetes." Their most optimistic values point to 21% of the U.S. adult population having type 2 diabetes in the year 2050. A middle-ground scenario predicts a prevalence of 25%-28%, while high-end data points to a diabetes prevalence of 33%, or 1 in 3 adults. To put these numbers in perspective, approximately 7% of the U.S. adult population had type 2 diabetes in 2007. In 1990, prevalence was below 5%.

Unlike some chronic diseases, type 2 diabetes risk can be reduced by relatively moderate lifestyle changes. Losing weight (if overweight or obese), improving dietary choices, and regular exercise are all known to reduce risk of acquiring type 2 diabetes. The authors of this paper note that such changes "can help to decrease loss in quality of life and the future cost of providing care for people with diabetes. Indeed, such efforts are essential if we hope to moderate or slow the growth of diabetes prevalence."

Boyle JP, Thompson TJ, Gregg EW, Barker LE, Williamson DF. Projection of the year 2050 burden of diabetes in the US adult population: dynamic modeling of incidence, mortality, and prediabetes prevalence. 2010. Population Health Metrics 8:29