Table of Contents
Magnesium is our bonus nutrient of concern today. This is the last nutrient in my series on the Habits of Unhealthy Vegetarians!
You’ll notice that magnesium is not a vegetarian-specific nutrient of concern. That is because it is a nutrient of concern for everyone. Americans are simply not getting enough magnesium in their diet anymore.
In the past, magnesium was not a nutrient of concern. So what happened?
Well magnesium is a common component of groundwater. When we drank from rivers and wells, we got magnesium (and other stuff!) that prevented deficiency. Now, we drink softened tap water and filtered bottled water.
The result, among other things, is a reduction in magnesium in our water supply!
So, does that mean it’s hard to get? Or that we can’t be healthy anymore?
Absolutely not.
Getting enough magnesium is just a matter of adding some foods that are great for us anyway.
Function
Magnesium’s biggest role in our body is as a co-factor. This means it almost constantly aids our enzymes in our body’s specific processes.
Magnesium is so essential because it is a co-factor in more than 300 metabolic processes! These include, but are not limited to:
- protein synthesis
- muscle and nerve function
- control of blood glucose
- control of blood pressure
- energy production
- bone development
- mood stabilization
Adequate magnesium intake has been linked to improved blood pressure, decreased risk of developing type 2 diabetes, relief from constipation and indigestion, improvement in symptoms of depression, and increased bone density.
Recommended Intake
According to the RDA, after age 18, we should aim to get around 400mg from food per day.
Here’s the thing with these recommendations: they may not be enough. Studies show that as our weight increases, so do our magnesium needs, which is simply not reflected in the current recommendations.
A simple calculation provides a better estimate of our needs: 6 mg of magnesium for every kg of body weight daily.
To do this, divide your weight in lbs by 2.2, then multiply by 6.
So a 130 lb woman would need to take in 355 mg of magnesium per day.
But let’s say she is 200 lbs. Her needs would increase to 545 mg of magnesium per day.
Sources of magnesium
Good news! The best sources of magnesium are vegetarian!
Almonds, spinach, cashews, peanuts, and shredded wheat cereal are the top 5 sources of dietary magnesium.
However, if you had one serving of each in one day, you would only get 356 mg of magnesium.
Other good sources include beans, brown rice, yogurt, and avocado.
Small amounts of magnesium can also be obtained from fish, chicken, and beef for those who eat meat. However, you will not meet your magnesium needs without including vegetarian sources of this mineral.
This is why I cannot stress enough how important it is for you to vary your diet and include lots of nuts, seeds, beans, whole grains, and vegetables.
Most vegetables have at least some magnesium, so when you vary your diet and eat enough of those nutrient-dense foods, you can easily meet your magnesium needs.
Symptoms of magnesium deficiency
Because magnesium has so much to do, deficiency symptoms can vary. Loss of appetite, fatigue, weakness, and vomiting can occur.
As deficiency continues, you can develop numbness and tingling, muscle cramps, personality changes, migraines, depression, and abnormal heart rhythms.
Magnesium deficiency has consistently been linked to worsening symptoms and/or medication resistance in mental health disorders, including depression, anxiety, and schizophrenia.
Magnesium deficiency is hard to diagnose. Symptoms can mimic other conditions, and blood work doesn’t reveal low serum levels until you’ve been deficient for a while. This is because most magnesium is stored inside our cells and bones.
Other tests are available, but nobody’s really loving any of them. They can be expensive, labor-intensive, and still unreliable.
Some evidence exists that most Americans have at least a mild magnesium deficiency, and that’s at the potentially too-low recommendations.
Causes of secondary deficiency
Remember that secondary deficiency occurs when you eat enough of the nutrient but still have deficiency symptoms.
Chronic alcoholism, certain medications, intestinal disorders, and type 2 diabetes are all at risk of secondary deficiency of magnesium.
This can be due to either poor absorption or increased excretion of magnesium.
Intense exercise may increase magnesium needs by 10-20% due to increased magnesium loss in sweat and urine. Almond butter on whole-grain toast may be the perfect post-workout snack.
Treatment for deficiency
Treatment for magnesium deficiency is supplementation until serum levels are normal AND symptoms of deficiency are gone.
As you are taking a supplement, you should also be working towards dietary changes that regularly include foods that are good sources of magnesium.
This is because studies have shown that magnesium consumption, rather than supplementation, improves mood and other deficiency symptoms more.
This is another one of those cases where a variety of different nutrients and phytochemicals work together.
Symptoms of magnesium toxicity
Magnesium toxicity from food is very unlikely because the kidneys will remove more if you eat more than your body needs.
However, high doses from medications or supplements can cause diarrhea, with or without nausea and abdominal cramping. Stopping the supplementation will cause the diarrhea to stop.
Long-term, excessive supplementation can lead to low blood pressure, nausea, vomiting, ileus (a dangerously slow digestive system), depression, and listlessness.
If toxicity is allowed to continue, the person can experience difficulty breathing, irregular heartbeat, heart attack, or death.
Patients with kidney disease are at higher risk of toxicity than other people.
This is because the kidneys are responsible for removing magnesium, and the magnesium removal system is impaired when the kidneys aren’t working normally.
Should I take a magnesium supplement?
If you know you have a deficiency, temporarily supplement with magnesium. Foods high in magnesium have tremendous health benefits, so you should try to get them anyway.
With almost all the nutrients we’ve discussed and some that we haven’t, it is almost always better to get them from foods. The health benefits are improved when the nutrient is allowed to intermingle with other compounds in our food.
This is exceptionally well documented in cases where magnesium is used to improve symptoms or increase medication response in depression.
Types of Magnesium supplements
Magnesium supplementation may be one of the most confusing vitamin and mineral supplements. There are so many different magnesium compounds available.
In alphabetical order:
- Magnesium chloride
- Well absorbed and can be used as a general magnesium supplement. Applied topically, this form of magnesium may help relieve sore muscles but will not likely raise your magnesium levels.
- Magnesium citrate
- Good for improving deficiency and, in high doses, is a powerful laxative. I recommend this form most often, as it is easily absorbed and cheaper than other options.
- Magnesium glycinate
- Easily absorbed and is likely the best form of magnesium to help with sleep. This is because, besides magnesium, glycine also appears to improve sleep quality. This form seems to be the most anti-inflammatory of the magnesium supplements, so it can be effective for conditions such as diabetes and heart disease. Additionally, it appears to be the most calming, so it may work better for mental health issues such as depression and anxiety.
- Magnesium lactate
- Generally used as a food additive for fortification rather than a supplement. It is easily absorbed and easier on the gut than other forms of magnesium. Some research indicates that this is a good form of magnesium to help with stress and anxiety.
- Magnesium malate
- Also well-absorbed and less likely to act as a laxative. Some research indicates this form of magnesium may be particularly useful in Fibromyalgia and Chronic Fatigue Syndrome, but higher quality research is needed.
- Magnesium orotate
- Easily absorbed and less likely to act as a laxative than other forms of magnesium. Orotic acid plays a role in DNA synthesis and energy production in the blood vessels. This makes it a popular form of magnesium for athletes. It also seems to have a very positive effect on Congestive Heart Failure. However, this form of magnesium supplement is much more expensive than others.
- Magnesium oxide
- Poorly absorbed but very good at correcting GI problems, particularly heartburn and constipation.Magnesium malate
- Magnesium sulfate/Epsom salt
- Can be mixed with water to treat constipation, but it tastes bad, and too much can be dangerous. Dissolved in bath water, it can soothe muscles and relieve stress. Some of the magnesium can be absorbed through the skin as a supplement, but this is not entirely verified.
- Magnesium taurate
- Appears to be the best form of magnesium to help with blood glucose and blood pressure control.
- Magnesium L-threonate
- very easily absorbed, and may be the best form of magnesium to improve brain health. Early research indicates this supplement may be best used for brain disorders such as depression, Alzheimer’s, and age-related cognitive decline.
Because different forms of magnesium have different absorption rates, it is difficult to advise on how much magnesium to take. Generally, you should follow the recommendations on the label unless otherwise instructed.
What supplementation won’t do
As always, supplementation is not going to negate a poorly planned diet.
Sources of magnesium tend also to be sources of fiber, other nutrients, and phytochemicals, whereas a supplement will be only the vitamin or mineral on the label.
Any concern for the omnivores?
Yes, many sources of magnesium are vegetarian, and they’re foods a vegetarian would be more likely to seek out.
Nuts, seeds, beans, and vegetables are good sources of magnesium, and vegetarians are more likely to reach for them.
Encourage your omnivorous buddies to eat nuts, seeds, beans, whole grains, and vegetables as well!
References
Recommended intake of magnesium
Learn More
Most of this series was focused on nutrients of concern for vegetarians, based on an article I wrote called Are You an Unhealthy Vegetarian?
That article would be a great place to start, and it has links to other articles in the series!
Jennifer Hanes MS, RDN, LD is a registered dietitian, mom, wife, and vegetarian in North Texas. She has dedicated Dietitian Jenn to be a source of information, ideas, and inspiration for people like her, vegetarians that live with people with different dietary beliefs and/or needs in a multivore household.