Tuesday, March 28, 2006

The Metabolic Magic of Magnesium

I often write about the nutrient-density of low-carb and controlled-carb diets because the evidence continues to highlight the importance of critical essential nutrients consumed more frequently with these eating patterns. Today, the journal Circulation published a study Magnesium Intake and Incidence of Metabolic Syndrome Among Young Adults, that found "young adults with higher magnesium intake have lower risk of development of metabolic syndrome."

Personally I don't necessarily agree with investigating micronutrients in isolation. The vitamins, minerals and trace elements we require for good health work synergistically with each other - so while a chronic deficiency in one micronutrient can wreck havoc on our metabolism, honing in on and focusing on one micronutrient may not do much for us without taking care of the other essentials that come into play when we consume the micronutrient in question.

Put another way - if we're eating the right foods, we're probably going to meet our essential requirements without having to worry about any one nutrient in particular. The foods that are most often recommended as part of a balanced low-carb or controlled-carb diet are the very foods that are rich in micronutrients - non-starchy vegetables, nuts, seeds, fish and some dairy.

Some of your best sources for magnesium are also your best sources of other essential nutrients....pretty convenient, huh?

For example, 1-cup of cooked spinach provides 156mg, or 39.1% of the RDA for magnesium (400mg). Spinach also provides more than 10% of the following essential nutrients too: Vitamin K, Vitamin A, Folate, Iron, Vitamin C, Riboflavin (B2), Potassium, Vitamin B6, Copper, Thiamin (B1), Phosphorus and Zinc.

The list of foods that provide 10% of more of our RDA for magnesium highlights how easy it really can be to meet your nutrient requirements for this essential nutrient each day while following a low-carb or controlled-carb diet. In the list below, I've provided some examples and also included other nutrients in each food that also exceed 10% of the RDA for the amount noted:
  • Swiss Chard - 1-cup cooked - 150mg magnesium (37.6% of RDA)
    10% or more of RDA for Vitamins K, A, C, E, Potassium, Copper, Iron and Calcium
  • Summer Squash - 1-cup cooked - 43mg magnesium (10%)
    10% or more of RDA for Vitamins C and A, potassium, copper and folate
  • Baked Halibut - 4-ounces cooked - 121.3mg (30%)
    10% or more of RDA for Vitamins B3, B6, and B12 and Selenium, Phosporus and Potassium
  • Baked Salmon - 4-counces cooked - 138.35mg magensium (35%)
    10% or more of RDA for Vitamins D, B3, B12, and B6 and Selenium and Phosphorus
  • Pumpkin Seeds - 1/4 cup - 184.5mg magnesium (46%)
    10% or more of RDA for Phosphorus, Iron, Copper and Zinc
  • Other foods that are rich (greater than 10% of RDA) in magnesium along with other essential nutrients include: Almonds, Cashews, Yellowfin Tuna, Scallops, Sesame Seeds, Sunflower Seeds, Flaxseeds, Avocado, Hazelnuts (filbets), Peanut Butter, Walnuts, and Plain Yogurt.

And they're all low-carb too!

All too often we hear misinformation about controlled-carb diets - that they are low in essential nutrients or nutrient deficient. Yet, when we look at the very foods encouraged and recommended, we find they're among the most nutrient dense available and easily integrated into a low or controlled-carb diet.

And, this particular study adds to the evidence from previous studies that found those who consume the most magnesium have lower risks.

From the Nurses' Health Study, Magnesium intake and risk of type 2 diabetes in men and women, researchers reported "a significant inverse association between magnesium intake and diabetes risk. This study supports the dietary recommendation to increase consumption of major food sources of magnesium."

From the Iowa Women's Health Study, Carbohydrates, dietary fiber, and incident type 2 diabetes in older women, researchers found "a protective role for...dietary magnesium in the development of diabetes in older women."

And from the Women's Health Initiative, Dietary magnesium intake in relation to plasma insulin levels and risk of type 2 diabetes in women, researchers concluded that "a protective role of higher intake of magnesium in reducing the risk of developing type 2 diabetes, especially in overweight women."

In my opinion it isn't just the magnesium that's working metabolic magic - it's the combination of essential nutrients that come together in the foods that are rich with magnesium. Foods rich with magnesium are also rich with other essentials - so eat your non-starchy vegetables, nuts, seeds and fish to ensure adequate intake of not only magnesium, but other critical vitamins, minerals and trace elements too!


  1. I so agree with you on not focusing so much on micronutrients that we isolate them. Your post is so helpful with its hard facts and encouragement to get this nutrient - by eating whole, less-processed foods that provide a whole other host of nutrition as well. I couldn't agree with you more. thanks for the info!

  2. Thanks Wendy!

    I am convinced it's not one or another sinlge nutrient that matters - it's meeting and/or exceeding all essential nutrients that matters and the foods encouraged on a low-carb or controlled-carb diet are often the richest for essential nutrients too!

  3. Anonymous10:13 PM

    Dear me, haven't we come a long way since Atkins?

    "Almonds, Cashews, Sesame Seeds, Sunflower Seeds, Flaxseeds, Hazelnuts (filbets), Peanut Butter, Walnuts."