Magnesium is another one of the essential micronutrients that support our health. Magnesium can be found inside our cells and bones, which can make it hard to assess our magnesium status. Additionally, there are many sources of magnesium including in our food, dietary supplements and through some medications. 


Role of Magnesium In The Body? 

Although you may not think it, magnesium plays tons of roles throughout the body! Not only does it make up a large portion of our bones, but it also found in our soft tissues and blood. Approximately 50% of the magnesium in our body is found in our bones, supporting their structure and development. Magnesium is also required as a co-factor for over 300 enzyme interactions in our bodies — including DNA and protein synthesis as well as blood sugar and blood pressure regulation. Additionally, magnesium is used in the transport of other nutrients such as calcium and potassium across cellular membranes and supports nerve functions and muscle contractions.


How Much Magnesium Do I Need?

Health Canada recommends health adults over the age of 18 consume between 310 to 420 milligrams of magnesium each day. Similar to other micronutrients, the amount of magnesium you need can vary based on your age and sex, as well as other factors including lactation and pregnant. You can check out Health Canada’s website for more information and a complete list of magnesium requirements.


Am I At Risk of Deficiency?

The magnesium levels in our body are tightly regulated by our kidneys. When our magnesium levels are low, our kidneys can reduce the amount of magnesium lost in our urine, making magnesium deficiency quite rare. However, there are some populations may be at an increased risk of deficiency including,

    • Older adults 
    • Individuals with GI diseases 
    • Individuals with alcohol dependence 
    • Individuals with diabetes 

The initial symptoms of magnesium deficiency include, 

    • Nausea and vomitting 
    • Fatigue  
    • Loss of appetite 

As magnesium deficiency progresses other symptoms may become apparent including,

    • Tingling in hands and feet 
    • Spontaneous muscle contractions 
    • Seizures 
    • Abnormal heart rhythm
    • Cramps 

Because of magnesium’s role in moving of other nutrients, a severe deficiency may lead to low levels of calcium in the blood (hypocalcemia) or low levels of potasisum in the blood (hypokalemia). For more information on the potassium and its role in our body, check out my Micronutrient Monday post on potassium.

Can I Have Too Much Magnesium? 

Our magnesium levels are tightly controlled by our kidneys. This means that excessive magnesium from our food doesn’t pose a significant risk to our health as the excess amounts can be eliminated in our urine. However, high doses of magnesium supplements can cause,

    • Diarrhea 
    • Stomach cramps
    • Nausea

In some rare cases, medications containing large doges of magnesium can lead to toxicity, including hypermagnesemia which can be fatal. Magnesium toxicity occurs when our blood contains more than 1.74 to 2.61 mmol/L of magnesium. Symptoms associated with toxicity include the high-dose symptoms and additional symptoms such as,

    • Hypotension
    • Lethargy 
    • Muscle weakness 
    • Difficulty breathing 
    • Irregular heart beat

Where Can I Find Magnesium? 

There are many sources of magnesium including foods in our diet, supplements as well as medications. 

Magnesium is naturally found in many plant- and animal-based foods, as well as water. Some of the top sources include, 

    • Roasted pumpkins seeds 
    • Chia seeds 
    • Almonds 
    • Cashews
    • Soy milk 
    • Edamame 
    • Smooth peanut butter 
    • Kidney beans 
    • Bananas 
    • Atlantic salmon

You can also find magnesium in tap, mineral and bottled waters. However the amount of magnesium can vary between sources and brands. 

Dietary Supplements

In addition to being found in food, magnesium can also be found in dietary supplements. Magnesium supplements can be found in various forms including,

    • Magnesium chloride
    • Magnesium oxide
    • Magnesium citrate
    • Magnesium lactate
    • Magnesium sulphate

Our bodies handle each of these forms of magnesium supplements slightly differently. In other words, our bodies may absorb more magnesium from one type of supplement than another type of supplement. Our bodies absorb the more water-soluble forms of magnesium than less-soluble forms.

Studies suggest that magnesium from magnesium chloride and citrate supplements are thought to be absorbed better by our bodies than the magnesium from supplements with oxide and sulphate. 

Interactions with Medications

Some medications can interact with magnesium supplements or have an impact on our magnesium levels including,

    • Bisphosphates 
    • Antibiotics 
    • Diuretics
    • Proton pump inhibitors (PPI)

Additionally, magnesium is be found as an ingredients in some medications, including laxatives and heart burn medications. It has also been suggested that consuming large amounts of zinc supplements can impair magnesium absorption and have a negative impact on our magnesium levels.

You should always check with your doctor or healthcare team before starting new supplements to prevent interaction and ensure you’re still meeting your body’s requirements.


For more on the role of vitamin and minerals in promoting health and supporting our bodies, check out the Micronutrient Monday series.