Jul. 26. 2017
Written By:
McKel (Hill) Kooienga
McKel Hill Kooienga, MS, RDN, LDN

McKel Hill Kooienga, MS, RDN, LDN

Founder of Nutrition Stripped and the Mindful Nutrition Method™

Discover the nutrition science behind the important mineral magnesium.

Why is magnesium important and why do you need it in your diet? What food sources are rich in magnesium and when, if at all, should you consider supplementation? Let’s take a look at the nutrition science behind this important mineral and make sure you’re getting enough!

What is Magnesium?

For as little as it’s talked about compared to macronutrients like protein or carbohydrates, magnesium is actually an incredibly important part of a functioning body (let alone a healthy, thriving one!). Over 300 enzymes use this essential micronutrient for important processes like ATP and synthesizing DNA, RNA, and proteins. Yes, we all know in theory that those processes are important, but what does it really mean when translated into our actual lives?

Our body contains about 25 grams of magnesium. Over 60% of that amount is found in the skeleton, 27% is found in muscle, 6% to 7% is found in other cells, and less than 1% is found outside of cells (1).

People often use magnesium for anxiety, constipation, indigestion, and pain. Promising studies have found a connection between magnesium and sleep, thyroid function, heart health, insulin sensitivity, and even mental health.

Magnesium Deficiency

As important as magnesium is, a good portion of the US population are lacking in this crucial mineral.

Unfortunately, this is largely because most people don’t get enough magnesium-rich foods in their diet. Magnesium is highest in foods like dark leafy greens, nuts, beans, and other plant foods that aren’t necessarily front-and-center in a conventional western diet.

Additionally, absorption without the right complementary vitamins—B12, D, and selenium—isn’t the easiest thing for our bodies to do, so not all of the magnesium we take in may necessarily be absorbed.

Plus, levels also tend to decrease with excess intake of alcohol, salt, coffee, phosphoric acid in sodas, and stress. Certain groups may be at a higher risk for low magnesium, including those with diabetes, those who consume alcohol, those with digestive disorders, athletes, and older adults.

These factors (especially for high-risk groups) can amp up the risk of deficiency, which has been linked to symptoms like:

  • muscle cramps
  • joint pain
  • headaches and migraines
  • acid reflux
  • heart arrhythmias
  • insomnia
  • anxiety
  • depression
  • hypothyroidism
  • hypertension
  • neuropathy
  • and many others!

If you notice any of these, you may try incorporating more magnesium-rich foods into your diet to see how you feel. Also, of course, be sure to get checked out by your physician and make an appointment with a registered dietitian, who can give you individualized nutrition coaching to help meet your needs.

Magnesium and Your Health

  • Heart Health: One of the most important roles of magnesium is promoting and ensuring a healthy heart. In fact, a deficiency in this key mineral has been linked to regulating blood pressure in those with hypertension and regulating heart arrhythmias (2).
  •  Thyroid Health: So many thyroid problems go undiagnosed, and low levels of magnesium may often be to blame (3). Signs of hypothyroidism include fatigue, weakness, headaches, and muscle cramps, all of which are also indicators of a deficiency. I’ve found nutrition-based approaches to help manage hypothyroidism, including magnesium, to be incredibly effective with my clients, so check out the list below of magnesium-rich foods if you struggle with these symptoms.
  • Sleep: Many people often use magnesium for sleep, and for good reason. A deficiency in this essential nutrient enhances stress and inflammation, which may also be linked to reductions in sleep duration and quality (4). Sleep is one of the most important parts of a healthy routine, and magnesium is often supplemented to promote healthful rest. Another way to relax at night and prepare for restful sleep is to take an Epsom salt bath. Epsom salt is magnesium sulfate, and, although it’s difficult to truly measure how much magnesium is absorbed in a bath, it’s still a great way to naturally calm down and quiet your mind. If baths aren’t your thing, I also love this tea for night time!
  • Bone Health: Because 50-60% of stored magnesium is found in our bones, it should come as no surprise that this important micronutrient plays a central role in bone health. Several population studies have shown a link between magnesium intake and bone density in both men and women (6). While magnesium isn’t the only factor important to bone health (hello, calcium!), this mineral is definitely worth paying attention to if you are at high risk for osteopenia or osteoporosis.
  • Migraines: Magnesium deficiency is linked to narrowing of the blood vessels and neurotransmitter release, which can result in headaches or migraines. Some studies have also found that supplementing with magnesium can help prevent migraines (7), which I know to be true for me personally as well. Make sure you’re staying hydrated, too!
  • PMS: Muscle cramps are a common sign of magnesium deficiency. In particular, low levels have been linked to extreme cramping in pregnant women (8). A magnesium supplement can help ease cramps, which is why I recommend the Natural Calm or Slow Mag to my clients, along with lots of rest with a warm bath to further relax muscles.
  • Diabetes: Type I and type II diabetics are at high risk for magnesium deficiencies. Fortunately, supplementation has been shown to help with regulating blood pressure and managing neuropathy in diabetics. If diabetes is part of your life, make sure to choose magnesium-rich foods at meals, or talk to your doctor and dietitian about supplementation.

How Much Do You Need?

Recommended daily intake of magnesium is about 400 mg/day, with some suggesting as high as 800 mg/day if you have any issues with nutrient absorption.

Of course, intake varies depends on how much your body needs. As a Registered Dietitian Nutritionist, my first piece of advice to clients (and you) is to eat foods high in magnesium and then fill in the gaps where you may need to through supplementation. Adding supplements can also help if you have any health challenges that cause issues with absorption or utilization.

Foods High in Magnesium

Magnesium is abundant in a variety of food sources, including many fruits, vegetables, nuts, seeds, and legumes. It can also be found in other ingredients, including fatty fish, whole grains, and even dark chocolate.

Here are a few of the best sources that you may want to consider adding to your diet:

  • Fruits (bananas, dates, figs)
  • Dark leafy greens (Swiss chard, spinach, kale, etc.)
  • Beans and legumes
  • Fatty fish (salmon, tuna, mackerel, halibut)
  • Avocado
  • Whole grains (buckwheat, oats, barley, quinoa, etc.)
  • Dark chocolate
  • Nuts (almonds, cashews, pecans, walnuts, Brazil nuts, etc.)
  • Tofu
  • Seeds (pumpkin seeds, flax seeds, and chia seeds)
  • Seaweed

For those of you who require more magnesium than can be provided with food-based sources, you can take a magnesium supplement.

Magnesium citrate and magnesium glycinate are often considered the best magnesium supplement options, since gastrointestinal side effects (hello, bathroom!) are more common with supplements like magnesium oxide or magnesium chloride. Magnesium malate, magnesium threonate, and chelated magnesium are other varieties that are widely available at health stores, pharmacies, and online retailers.

Magnesium-rich recipes: 

NS Recommends

Magnesium is an important mineral that plays a key role in several aspects of health. In fact, studies show that it can help improve sleep quality, prevent migraines, increase bone density, support heart health, and more. A deficiency can also have serious side effects, which range from muscle cramps to joint pain, anxiety, and acid reflux.

Available in a wide variety of healthy ingredients, getting in your daily dose of magnesium doesn’t have to be difficult. Although some may need supplementation, most people will be able to meet their needs through food sources alone by incorporating a variety of fruits, veggies, whole grains, and protein foods into their daily diet.

If you’re looking for more support and ways to integrate more magnesium into your life, then check out our Wellness Coaching. We offer appointments virtually and all of our NS Wellness Coaches are professionally trained to give you expert guidance and practical plans for long-term health! Click here to take the client quiz.