Did you know that magnesium is an important factor in over 300 biological reactions? Although this crucial mineral can sometimes get overlooked, it’s involved in many essential bodily activities.
Here’s what you need to know about magnesium, including how to ensure you’re getting enough:
Magnesium contributes to your overall health in many ways, including:
- Relaxing the muscles, including the heart and skeletal muscle
- Acting as a co-factor for enzymes needed to metabolize carbohydrates, fats, and proteins
- Supporting protein synthesis and healthy calcium deposition – essential for the formation of teeth, bones, and tissue
Magnesium can also cross the blood-brain barrier and plays a role in supporting the activity of calming neurotransmitters that can encourage healthy sleep.
Because of its role in a wide range of bodily processes, low levels of magnesium can cause a variety of health issues. Some symptoms of magnesium deficiency include cramps and muscle tension, difficulty sleeping, headaches, low energy, and feelings of anxiousness. Low magnesium status has also been linked to a higher incidence of menstrual problems and painful periods.
Severe dietary magnesium deficiency is uncommon in affluent societies, but high intakes of fat or calcium can intensify magnesium insufficiency, especially under conditions of stress. Physical, emotional, and endogenous sources of stress can all affect our need for magnesium.
Genetic differences in how the body absorbs and uses magnesium may also account for differences in our vulnerability to magnesium deficiency and differences in our body’s physical responses to stress.
How Much Magnesium Do You Need Daily?
The Recommended Dietary Allowance (RDA) for magnesium is 320 mg daily for most adult women, and 420 mg daily for most adult men. You might need a higher intake, however, if you are under increased stress, are very physically active, or take certain medications that deplete magnesium stores or bind to magnesium, blocking absorption.
Health Canada recommends the following daily intake of magnesium for different age groups: 
|Life stage group||Magnesium (mg/day)|
|Adolescent males||9–13 y||240|
|Adult males||19–30 y||400|
|≥ 70 y||420|
|Adolescent females||9–13 y||240|
|Adult females||19–30 y||310|
|≥ 70 y||320|
Some medications known to interact with magnesium include: 
- Loop and thiazide diuretics
- Estrogen and oral contraceptives that contain estrogen
- Tetracyclines, penicillamines, and etidronate
Individuals with impaired renal (kidney) magnesium excretion and anyone with kidney disease should not take magnesium supplements without first consulting their health care practitioner, in order to avoid the risk of developing hypermagnesemia. The same goes for anyone with atrioventricular block, since magnesium supplements may risk worstening this issue.
As you can see, it’s best to talk to your health care practitioner prior to using magnesium supplements.
Magnesium is vital for a wide range of physiological processes essential for good health. Where possible, it’s best to obtain your daily requirement of magnesium through foods as these provide additional beneficial nutrients.
Fortunately, magnesium is found in many common foods. Some of the richest food sources of magnesium include:[4,5]
- Green leafy vegetables like spinach: 1 cup contains 157 mg
- Black eyed peas: 3/4 cup contains 121 mg
- Seeds: 1 tbsp pumpkin seeds contains 84 mg; 1 tbsp chia seeds contains 47 mg
- Dark chocolate: 50 g contains 115 mg
- Cooked salmon: 75 g contains 92 mg
- Almonds: 1/4 cup contains 90 mg
- Whole grains like brown rice: 1 cup (cooked) contains 80 mg
- Lentils: 1 cup cooked contains 70 mg
- Soy milk: 1 cup contains 61 mg
- Avocado: 1 medium avocado contains 58 mg
- Smooth peanut butter: 2 tbsp contains 50 mg
- Bananas: 1 medium banana contains 30 mg
- Strawberries: 1 cup contains 20 mg
An easy way to increase your intake of this important mineral – and satisfy around 40% of the recommended daily intake – is by adding a handful of spinach to your lunchtime salad. Another suggestion is to add the following ingredients into a blender for a simple breakfast smoothie that provides 208 mg of magnesium:
- 1 cup soy milk
- 1 medium banana
- 1 cup strawberry halves
- 2 tbsp peanut butter
- 1 tbsp chia seeds
While many foods provide a natural source of magnesium, you may want to consider taking a magnesium supplement if you suffer from digestive issues, have a high level of stress, take medications that deplete magnesium, or aren’t eating at least three servings of vegetables a day.
Magnesium supplements are generally well tolerated, with the biggest side effect being diarrhea if you take too much. It’s important to choose a quality supplement that is easily absorbed by the body, has a sustained release, and poses little risk of stomach upset.
Magnesium citrate is one of the best absorbed forms of magnesium, especially compared to magnesium oxide.[7,8,9]
Magnesium oxide contains a higher level of the mineral compared to other forms, which can help reduce the amount you need to take. This form tends to be a little harder on the gastrointestinal system, however, so if you’ve experienced digestive upset after taking magnesium oxide, consider switching to a gentler form.
A quick and easy way to add a magnesium supplement to your diet is with Magnesium Citrate powder from Natural Factors. Available in two delicious flavours – berry and tropical fruit – simply add a scoop to a glass of water!
If you think you may be low in magnesium, consult with your health care practitioner and check out Natural Factors’ complete line of magnesium supplements.
 Natural Medicines Comprehensive Database. Magnesium. Available from: https://naturalmedicines.therapeuticresearch.com/databases/food,-herbs-supplements/ [Accessed 7th March 2019].
 Schlingmann KP, et al. Genetics of hereditary disorders of magnesium homeostasis. Pediatr Nephrol. 2004 Jan;19(1):13-25.
 Health Canada. Drugs and Health Products: Magnesium. Health Canada, 15 November 2007. Available from: http://webprod.hc-sc.gc.ca/nhpid-bdipsn/monoReq.do?id=135&lang=eng [Accessed 7th March 2019].
 Dieticians of Canada. Food sources of Magnesium. Available from: https://www.dietitians.ca/Downloads/Factsheets/Food-Sources-of-Magnesium.aspx [Accessed 7th March 2019].
 USDA. Food Composition Database. Available from: https://ndb.nal.usda.gov/ndb/search/list [Accessed 7th March 2019].
 Razzaque MS. Magnesium: are we consuming enough? Nutrients. 2018 Dec;10(12):1863.
 Walker AF, et al. Mg citrate found more bioavailable than other Mg preparations in a randomised, double-blind study. Magnes Res. 2003 Sep;16(3):183-191.
 Lindberg JS, et al. Magnesium bioavailability from magnesium citrate and magnesium oxide. J Am Coll Nutr.1990 Feb;9(1):48-55.
 Kappeler D, et al. Higher bioavailability of magnesium citrate as compared to magnesium oxide shown by evaluation of urinary excretion and serum levels after single-dose administration in a randomized cross-over study. BMC Nutr. 2017;3:7.