Magnesium Foods and Cardiovascular Health

Dietary Magnesium and Magnesum SupplementsA whole slew of news reports have recently covered two studies of the effects of dietary magnesium on cardiovascular health and strokes. It’s certainly good news, as it shows a clear connection between dietary magnesium intake and the two. The problem with the new reports, though, is that many of them simply say magnesium intake and leave the “dietary” part off. This is a big mistake.

People who read these reports may rush out and buy magnesium supplements to improve their cardiovascular performance. And that’s not a good idea, because there was nothing in the studies to connect magnesium supplements to cardiovascular improvement and reduce risk of stroke. The studies specifically looked at dietary magnesium, which means increased magnesium from eating magnesium rich foods.

Now the good news, if you are one of those who are ready to eat magnesium foods rather than popping pills.

In seven prospective studies, with 6477 cases of stroke and 241,378 participants researchers observed

…a modest but statistically significant inverse association between magnesium intake and risk of stroke. An intake increment of 100 mg Mg/d was associated with an 8% reduction in risk of total stroke (combined RR: 0.92; 95% CI: 0.88, 0.97), without heterogeneity among studies (P = 0.66, I2 = 0%). Magnesium intake was inversely associated with risk of ischemic stroke…

Again, this 100mg per day hasn’t been shown to work if you get it from a supplement. To get the effects noted in this study you need to get that 100mg of magnesium from food. It’s about 100 pumpkin seeds, 33 almonds, or a small serving of fish or spinach.

There are times when magnesium supplements have been shown to be effective, but this is not one of them. Be very careful when you use magnesium to treat a certain health issue, as in some cases the supplements to not have the efficacy of dietary magnesium. Don’t rely one blogs (not even this one) to give you this info. Look for the source of the study cited. Copy and paste it into Google, and read the abstract for yourself. It will take all of a minute or two. Make sure the study specifies either supplements or dietary magnesium. If it doesn’t, then it’s safer to assume that only dietary magnesium will work, as that’s often the case.

This particular abstract (Dietary magnesium intake and risk of stroke: a meta-analysis of prospective studies1,2,3,4, Susanna C Larsson, Nicola Orsini, and Alicja Wolk) can be found at the American Journal of Clinical Nutrition.

be found here.

Magnesium and Diabetes

Magnesium Rich Foods Reduce Diabetes RiskDiabetes Insulin DNA

Maybe it’s a happy coincidence, but foods high in magnesium also tend to be incredibly healthy. In that vein, two studies by Harvard researchers suggested that a diet of magnesium rich foods can help prevent the onset of Type II diabetes.

The 2007 National Diabetes Fact Sheet estimates that 23.6 million people in the USA suffer from diabetes, the vast majority of those being Type II. It was also the 7th leading cause of death in the USA in 2006.

Two separate teams of researchers at the Harvard School of Public Health and Harvard Medical School (HMS) published their findings on magnesium and the associated reduced type II diabetes risk in the January 2004 issue of Diabetes Care.

One study used data from the Women’s Health Study (WHS) to track 38,025 women from 1993 through 1999. The other study looked at 85,060 women identified by the Nurses Health Study (NHS), and who were tracked for 18 years, and 42,872 men chosen from the Health Professionals Follow-Up Study who were tracked for 12 years.

The participants in both studies were adults. None had any personal history of diabetes, cardiovascular disease or cancer.

Magnesium was shown to have played a positive role in reducing the risk of type II diabetes in both studies. The WHS team concluded that only overweight and obese women would have a reduced risk of type II diabetes onset with increased magnesium intake, while the NHS study found that men and women of all weight groups would have decreased type II diabetes risk.

HMS Assistant Professor of Medicine Simin Liu, the study’s author, said he believed the studies differed because of differing definitions of “overweight.” In the WHS study, a woman was considered overweight if her BMI (total body fat), was above 25, which is the lower limit of an overweight categorization as defined by the National Institute of Health.

The NHS study, though, used a BMI of 27 to define an overweight person. HMS Assistant Professor of Medicine Frank B. Hu, the study’s author, said this was because 27 is the median BMI for overweight people. He added that his findings on dietary magnesium intake were independent of BMI and would not have changed with a different BMI index. He defended his study as the more accurate study because of the larger pool of participants in the NHS group.

In spite of these disagreements, both studies agreed that the general population would benefit from increased dietary magnesium intake, and that Americans generally fall short of the recommended levels of magnesium rich foods in their diet. This has been one factor suggested as a cause of the increasing cases of type II diabetes in the population.

A previous Harvard study, published in the Journal of the American College of Nutrition, suggested that higher dietary magnesium intake may reduce the risk of developing type II diabetes, because women with higher magnesium consumption tend to have greater insulin sensitivity. Decreased insulin sensitivity, also called insulin fasting, is the immediate cause of type II diabetes.

“The primary concern here is not which group is affected the most,” Hu commented“Whether you are overweight or obese or not, you need enough magnesium.”

Magnesium Supplements Do Not Have This Same Effect

Even while magnesium rich foods have shown a positive effect in preventing diabetes, the studies further found that multivitamins and other magnesium supplements have not shown similar effects.

“The NHS study didn’t show any supplemental effect of magnesium, only of magnesium-rich foods,” said Dr. Liu.

“This suggests that there may be something else in those foods that works with magnesium to reduce diabetes risk. For now, I can only recommend foods that are rich in magnesium.”

Magnesium rich foods include whole grains, nuts, and green leafy vegetables, broccoli, tofu and other items.

Hu and Liu both agreed there should be continued research to better determine the effects of magnesium and magnesium supplements on type II diabetes.