Low Magnesium Tied to Diabetes RiskJuly 2004
Magnesium plays a vital role in the storage and utilization of energy. Although magnesium is ubiquitous in food sources, especially in dark green leafy vegetables, magnesium deficiency continues to be common, affecting up to 10% of seemingly healthy adults and up to 65% of patients in the intensive care setting.1 Moreover, a new study strongly correlates high magnesium intake with a reduced risk of developing type II diabetes.2
Of those with type II diabetes, approximately 39% suffer from magnesium deficiency.3,4 This reduces insulin sensitivity, thereby altering glucose homeostasis. Furthermore, magnesium deficiency accelerates the complications of diabetes, including retinopathy, thrombosis, and hypertension.
This deficiency generally is not due to inadequate dietary intake, but instead to excessive gastrointestinal losses (from malabsorption, diarrhea, or bowel resection) or renal losses (for example, hypercalcemia, alcohol abuse, or the use of diuretics, chemotherapeutic agents, or antibiotics). Magnesium deficiency also occurs as a metabolic derangement of both thyroid and parathyroid disorders, and most often is a symptom of an underlying disease.
In research published in the journal Diabetes Care, low magnesium intake in women was tied to an increased risk of developing diabetes, particularly in those who are overweight.2 Women with the highest magnesium intake (433 mg/day) were up to 22% less likely to develop diabetes than those with the lowest intake (255 mg/day).
Although people with low-normal or even abnormally low levels of magnesium may be asymptomatic, the classic symptoms of magnesium deficiency are neuromuscular hyperirritability and cardiac arrhythmias. Magnesium status can be easily determined by a blood test or magnesium tolerance test. For those who are asymptomatic or mildly symptomatic, oral replacement with magnesium oxide (1-2 grams daily in divided doses) is recommended.
—Dean S. Cunningham, MD, PhD
1. Ryzen E, Wagers PW, Singer FR, Rude RK. Magnesium deficiency in a medical ICU population. Crit Care Med. 1985 Jan;13(1):19-21.
2. Song Y, Manson JE, Buring JE, Liu S. Dietary magnesium intake in relation to plasma insulin levels and risk of type 2 diabetes in women. Diabetes Care. 2004 Jan;27(1):59- 65.
3. Walti MK, Zimmermann MB, Walczyk T, Spinas GA, Hurrell RF. Measurement of magnesium absorption and retention in type 2 diabetic patients with the use of stable iso- topes. Am J Clin Nutr. 2003 Sep;78(3):448-53.
4. Barbagallo M, Dominguez LJ, Galioto A, et al. Role of magnesium in insulin action, diabetes and cardio-metabolic syndrome X. Mol Aspects Med. 2003 Feb-Jun;24(1-3):39- 52.
|Women with High Iron at Risk for Diabetes|
Could a simple blood test determine your risk of developing diabetes in the future? Doctors may one day be able to identify patients at risk by checking their stored iron levels.
A recent study published in the Journal of the American Medical Association (JAMA) found that women with above-average stored iron levels (as measured in the blood by both the concentration of transferring receptors to concentration of ferritin and the concentration of ferritin alone) were at risk of developing type II diabetes.* The 10-year study tracked the health status of more than 38,000 women who donated blood samples. Of this group, 698 women were diagnosed with type II diabetes. On average, the diabetic women had higher indicators of stored iron levels than those who were not diagnosed with the disease.
The JAMA study found that the risk for developing diabetes was almost three times greater in those with the highest blood ferritin levels compared to those with the lowest levels. Ferritin is a crystalline iron-containing protein that indicates the amount of iron in the body. Normal ferritin levels for women range from 12 to 150 ng/ml. In the JAMA study, the average ferritin level in those who developed diabetes was 109 ng/ml compared to 71.5 ng/ml for those who did not develop diabetes.
Many people with type II diabetes often have no symptoms or have symptoms so mild that they may not notice them until the onset of complications. According to the American Diabetes Association, 16 million Americans have type II diabetes, but up to one-third of them are not even aware that they have the disease. Using blood tests to identify those at risk for diabetes may be helpful in facilitating preventive measures such as diet and lifestyle changes to avoid onset of the disease.
* Jiang R, Manson JE, Meigs JB, Ma J, Rifai N, Hu FB. Body iron stores in relation to risk of type 2 diabetes in apparently healthy women. JAMA. 2004 Feb 11;291(6):711-7.
|Lycopene Helps Women Avoid Heart Disease|
Heart disease is the number-one killer of women, responsible for nearly twice as many deaths of US women as all forms of cancer and strokes. Recent studies have found that lycopene, a powerful carotenoid and antioxidant found in foods such as tomatoes, can significantly reduce a woman's chances of developing heart disease.
One widely publicized study, led by Dr. Howard Sesso of the Harvard School of Public Health, followed nearly 40,000 women over an 11-year period.1 The study found that women who consumed seven or more servings of foods high in lycopene, such as tomatoes (and even tomato sauce and pizza), reduced their risk of developing heart disease by 30% compared to a similar group of women who ate less than 1.5 servings per week of lycopene-rich foods.
In a more recent follow-up study, 483 women were identified as having significant heart disease.2 After comparing these women with 483 women who did not have heart disease, it was shown that blood lycopene levels were significantly correlated with the risk of developing heart disease. Women with the highest amounts of blood lycopene were found to have a 34% lower risk of developing heart disease.
The study authors concluded: "higher plasma lycopene concentrations are associated with a lower risk of [cardiovascular disease] in women."
—Edward R. Rosick, DO, MPH, MS
1. Sesso HD, Liu S, Gaziano JM, Buring JE. Dietary lycopene, tomato-based food products and cardiovascular disease in women. J Nutr. 2003 Jul;133(7):2336-41.
2. Sesso HD, Buring JE, Norkus EP, Gaziano JM. Plasma lycopene, other carotenoids, and retinol and the risk of cardiovascular disease in women. Am J Clin Nutr. 2004 Jan;79(1):47-53.