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Magnesium reduces stroke

Magnesium, the forth most abundant mineral in the body is linked to better blood pressure. In the study, researchers reviewed every magnesium and stroke study from 1966 through September, 2011 covering 241,378 participants and 6,477 cases of stroke.

Researchers found a direct link: for every 100 mg increase in magnesium per day, there was a 9 percent decrease in the chances of having an ischemic stroke, where blood supply to the brain is blocked.

Discussing their findings, doctors suggested people should eat more magnesium-rich foods such as green leafy vegetables, beans, nuts and whole grains, and that further study may move the U.S. to begin recommending magnesium supplements to reduce chances of stroke. The current recommended dietary allowance for magnesium for adult men is 420 mg per day, and for adult women, 320 mg per day.

Magnesium reduces colorectal cancers

In this review, doctors analyzed eight magnesium and cancer studies involving 338,979 participants. Overall, compared to those who got the least, people who consumed the highest daily average amount of magnesium were 11 percent less likely to develop any form of colorectal cancer.

There was a direct link: for every 50 mg increase in magnesium per day, there was an average 6 percent decline in the chances for colorectal cancer, colon, or rectal cancers. Six of the studies adjusted for how much calcium was in the diet and in those studies, participants who got the most magnesium were 19 percent less likely to develop colon or rectal cancer compared to those who got the least magnesium.

Reference: American Journal of Clinical Nutrition; 2012, Vol. 95, No. 2, 362-6

From the March 2013 newsletter

Antioxidants and pancreatic cancer

In this large study, doctors measured the diets, food-cooking methods, and vitamin C levels of 23,658 men and women, aged 40 to 74. Over the course of 10 years of follow-up, 49 participants developed pancreatic cancer, 55 percent men. Researchers then calculated the nutrients in their diets and compared to 3,970 participants who had not developed pancreatic cancer.

Compared to those who consumed the least selenium, those who consumed the most selenium were half as likely to have developed pancreatic cancer. Those who consumed the most selenium and vitamins C and E were 67 percent less likely to develop the cancer compared to those who got the least of these antioxidants.

Discussing their findings, doctors said, “It seems the antioxidants are knocking out the pro-oxidants that are perhaps causing the damage that leads to cancer, and therefore playing a protective role.”

Magnesium and colorectal cancer

There are few studies on magnesium and colorectal cancer, doctors said, but these two new analyses suggest magnesium may help prevent this disease. In the first study, researchers compared 768 people with colorectal cancer to 709 similar people without. In a group of those who were at least age 55, with a body mass index score of 25 or higher, each 100 mg increase in magnesium per day decreased chances for colorectal cancer by 12 percent.

In the second study, doctors reviewed findings from other magnesium-colorectal cancer trials and found that for every 100 mg increase in daily magnesium, there was a 13 percent decrease in chances of pre-cancerous colorectal adenomas and 12 percent less chance of colorectal cancer.

Reference: Gut - International Journal of Gastroenterology and Hepatology; July, 2012. Electronic Prepublication

From the December 2012 newsletter

Magnesium reduces blood pressure

Up until now, evidence linking magnesium to better blood pressure has been inconclusive. Researchers in this review looked at all the magnesium studies to date and found 22 trials involving 1,173 people, who took 120 mg to 973 mg of magnesium per day for three to 24 weeks. Combining the data, doctors found that overall, magnesium reduced systolic blood pressure by 3 to 4 mmHg, and diastolic blood pressure by 2 to 3 mmHg, with the best results for doses over 370 mg of magnesium per day.

The blood pressure measurements, systolic and diastolic, relate respectively to when the heart contracts to pump blood out, and when it relaxes to refill. In discussing their findings, doctors said supplementing with magnesium appears to achieve a “small but clinically significant reduction in blood pressure”, and suggests larger controlled trials to confirm these results.

Vitamin C reduces high blood pressure

The evidence for the blood pressure benefit of vitamin C is also inconsistent. In this new analysis, doctors reviewed 29 placebo-controlled vitamin C supplement trials with 10 to 120 participants, average daily doses of 500 mg of vitamin C, and an average study period of eight weeks. Combining the data, researchers found that overall systolic blood pressure declined by 3.84 mmHg, and diastolic blood pressure declined by 1.48mmHg. The effects were greater in those with high blood pressure, with systolic and diastolic blood pressure declining respectively by an average of 4.85 mmHg and 1.67 mmHg.

In talking about their findings, researchers said doctors might eventually be able to recommend vitamin C to prevent or help treat high blood pressure, and suggested larger studies to confirm the blood pressure benefits of vitamin C.

Reference: European Journal of Clinical Nutrition; 2012, Vol. 66, No. 4, 411-8

From the July 2012 newsletter