Lowering Risk for Type 2 Diabetes
Higher Magnesium Intake May Lower Risk for Type 2 Diabetes
In a study involving more than 2,500 people, those with the highest magnesium intake had the lowest risk of developing type 2 diabetes over a 7-year period, as reported online ahead of print in Diabetes Care.
“There is a substantial body of literature linking low magnesium intake or low magnesium status (as measured in the blood) to greater risk of diabetes,” added lead author Adela Hruby, PhD, MPH, who was a graduate student at the Tufts University Friedman School of Nutrition when she conducted this research, and is now a Research Fellow at the Harvard School of Public Health.
“In contrast to other micronutrients, relatively little attention is given to adequate magnesium as an important part of a healthy diet." she said. "In fact, we know from national surveys, as well as in our own research populations, that somewhere between 50% and 75% of Americans have inadequate magnesium intake. When compared to a similar mineral, like calcium, which many Americans get more than enough of, the low magnesium intake presents a striking contrast."
The study involved 2,582 healthy people aged 26 to 81 years at baseline who are enrolled in the Framingham Heart Study (FHS) Offspring study. Approximately 42% of the participants were overweight, 21% were obese, and none had diabetes.
More Than Half of Patients Had Low Magnesium Intake
Low magnesium levels were reported by approximately half of women and 75% of men in the study. After 7-years of follow-up, participants with the highest intake of magnesium had a 37% lower risk of developing metabolic impairment (P for trend =0.02). Among participants who already had metabolic impairment at baseline, higher intake of magnesium was linked to a 32% lower risk of new-onset diabetes (P=0.05).
The overall risk of diabetes was 53% lower among people with the highest magnesium intake compare to those with the lowest intake (P for trend =0.0004). This association was attenuated by adjustment for risk factors and dietary fiber intake in the overall cohort, but not in the subgroup with metabolic impairment at baseline.
“This is a strong study, due to its large sample size, the length of the study (7 years), and all of the measures of insulin sensitivity,” commented Stella Lucia Volpe, PhD, RD, LDN, Professor and Chair, Department of Nutrition Sciences, College of Nursing and Health Professions, Drexel University, Philadelphia. “In addition, they included those who did not have diabetes mellitus to establish if dietary intake can prevent diabetes mellitus over time,” she said.
“The weaknesses of the study are that the researchers were only able to establish a correlation and not a cause and effect,” Dr. Volpe said. “Secondly, the researchers measured dietary intake of magnesium, but they did not measure blood or urinary measures of magnesium to establish if the participants had an established magnesium deficiency,” she added.
“Achieving a diet high in magnesium is relatively simple,” said senior author Nicola M. McKeown, PhD, a scientist at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston. “Examples of foods rich in magnesium include leafy greens (magnesium is at the center of the chlorophyll molecule), whole grains (most of the magnesium is in the outer part of the grain), nuts and seeds, dark chocolate, and coffee.
Along with high magnesium, these foods are rich in dietary fiber and/or other phytochemicals shown to be protective against diabetes. Generating mindful healthy eating habits and increasing physical activity prior to the onset of diabetes, particularly among those at risk, are likely the most important things that primary care physicians and endocrinologists can encourage their patients to do,” she said.
“We hope that the results of this study will draw additional attention to magnesium by highlighting a potentially novel aspect of its application: that is, that those who are already at metabolic risk of developing diabetes may benefit from increasing magnesium in their diets,” Dr. Hruby said.
“Although not addressed in this study, adequate nutrient status in metabolically compromised patients is frequently overlooked in the clinical setting,” Dr. McKeown said. “Perhaps having a look at nutrient status and/or dietary intake in these patients would help them manage their conditions better,” she said.