Magnesium – Frequently Asked Questions


The human body cannot produce magnesium so ensuring you get enough is essential as it is responsible for many functions in the body running efficiently. This article will aim to answer some of the most common questions about the supplement. 

**Please note that supplement guidance is recommended if you are deficient in magnesium and cannot boost levels if not deficient.**

What is it?

Magnesium is a mineral that is used for around 300 biochemical reactions in the body (1). The majority of magnesium in the body can be found in bone, muscle and soft tissue. Research has indicated that magnesium is responsible for maintaining muscle function (2), supporting a healthy immune system (3), keeping the heart beat steady (4), and helps to strengthen bones (5). It has also been found to help maintain blood glucose levels, (6), and aid in the production of energy and protein. 


There are many different types of magnesium that is available in supplements, below are some of the popular types;

  • Magnesium citrate


Magnesium Citrate is the most common form of magnesium found in supplements, this is due to its high bioavailability, meaning greater absorption from the digestive tract, so more of it works in the body instead of being excreted, (11). It is formed with citric acid, which is commonly found in fruit.


  • Magnesium lactate


Magnesium lactate is generally used in foods and is formed with lactic acid, (another popular food preservative), where it is used to regulate the acidity of foods and fortify drinks. However its use as a supplement is not common, it has been found that people with a severe deficiency  in magnesium may prefer this form as the high doses of most other types of this mineral can cause constipation (12,13). There is a lack of evidence as to its effectiveness with stress and anxiety (14).


  • Magnesium aspartate


Magnesium Aspartate is similar to magnesium citrate in that it is very bioavailable. Aspartate is an amino acid which binds to magnesium, as well as other minerals, (copper, zinc, iron, etc),  to make it more bioavailable. 


  • Magnesium chloride


Magnesium chloride is another popular form of magnesium. One of the most common uses of this type of magnesium is used in creams or lotions, however there is little evidence that this helps with the claims of sore muscles recover from exercise, (15). It is certainly safe in supplement form as by binding the mineral chlorine it gives it a more potent bioavailability.


  • Magnesium malate


Magnesium is formed with malic acid to make magnesium malate. It can be absorbed well in the digestive tract, and help to keep magnesium levels in the body high for a prolonged period of time, (16). There has been the suggestion that this form of magnesium can help with fibromyalgia, (17), however research in this area is sparse, more evidence is needed to fully elucidate the effects.


  • Magnesium taurate


Magnesium Taurate has been suggested to help improve blood glucose levels, by reducing insulin resistance and improving blood pressure levels (18). This type of magnesium has also been found to have the quickest uptake in soft tissue, (16).

Is it effective?

Research on effectiveness on magnesium is scarce, however this could be due to the fact that magnesium in conjunction with other minerals help with bodily functions and is hard to separate it individually to prove effectiveness. That being said, research has observed a correlation between magnesium levels and metabolic syndrome (7), high blood pressure (hypertension), (8), inflammation, (9) and insulin resistance (10). 

How do they work/help?

As was mentioned earlier magnesium is responsible, in conjunction with other minerals, for many bodily functions. 

Blood Glucose Levels – Some evidence


Magnesium has the potential to help with insulin resistance, possibly due to it helping glucose transportation in the muscles and cells, a key issue in type 2 diabetes mellitus (T2DM). 

An Initial symptom of pre diabetes and T2DM is frequent urination (25).  This increased urination could flush out significant amounts of magnesium thus impairing its effect. There is not sufficient evidence to suggest that it can help and more research is needed (26).

Blood Pressure – More research needed


There have been some studies looking at the effects of magnesium on blood pressure, and at best it has been found to lower diastolic pressure slightly (27).

One issue with studies that have looked at the effects of magnesium on blood pressure is that they can be combined with calcium and potassium both of which can are known contributors to helping reduce blood pressure, (28) and so more research is needed to fully elucidate its effect on blood pressure.

Osteoporosis – Some evidence


The human bone constantly changes density and is partly due to diet and physical activity. Osteoblasts and osteoclasts are responsible for bone formation, all of which are dependent on magnesium levels, (29). This  has resulted in magnesium supplementation recommended for anyone who may be at risk of osteoporosis, (30).

Are they Safe? (RDA)

When consuming magnesium naturally through food sources (dark leafy greens, pumpkin seeds, almonds, etc..), it would take a considerable amount to exceed safe levels, as the body can eliminate amounts through urination. However when consuming supplements if you take more than the recommended daily amounts it can cause side effects such as diarrhoea, nausea and muscle cramps. 

It is important to note that some supplement labels may list the weight of the salt of the element but others state the amount of the mineral itself. Therefore make sure you look for the ‘elemental magnesium amount’ on the label to ensure you know your true amount. Below shows the Recommended Daily Amount (RDA), for different individuals, (19). 


Age Male Female Pregnancy Lactation
Birth to 6 months 30 mg* 30 mg*
7–12 months 75 mg* 75 mg*
1–3 years 80 mg 80 mg
4–8 years 130 mg 130 mg
9–13 years 240 mg 240 mg
14–18 years 410 mg 360 mg 400 mg 360 mg
19–30 years 400 mg 310 mg 350 mg 310 mg
31–50 years 420 mg 320 mg 360 mg 320 mg


How are they made?

As we have mentioned earlier magnesium doesn’t exist freely on its own, so in order to be effective it needs to be bound to an element, (eg. citrate salt, oxide, lactate, etc), this will help to determine both its bioavailability and dosage, as different elements can hold more. 

Who needs it?

Magnesium is needed for everyone; however if you believe you may need to supplement magnesium always talk to a healthcare professional especially if on other medications as it is known to interfere with diuretics, antibiotics and heart medication.

If you have any underlying health conditions it is also recommended to consult a healthcare professional this includes conditions like, crohn’s disease, diabetes (both type 1 & 2), kidney disease or heart disease.  

Side effects

Certain side effects of too much magnesium can include stomach cramps, diarrhea, muscle weakness, low blood pressure, nausea and fatigue.

Having too little and being deficient in magnesium can lead to muscle twitches, fatigue and loss of appetite, (19). 

More severe symptoms that are associated with low levels of magnesium are high blood pressure, (20), asthma, (however the evidence is sparse), (21), irregular heart beat, (22) and osteoporosis, (23).    


In order for Vitamin D to work effectively your body will also require certain levels of other vitamins, including magnesium. 

To get vitamin D3 to convert to the bioavailable version, ‘calcitriol’, it needs to pass through the liver and kidneys to add oxygen and hydrogen molecules; this can only happen if there are sufficient levels of magnesium to perform the task, (24).






1 – Ryan, M. F. (1991). The role of magnesium in clinical biochemistry: an overview.Annals of Clinical Biochemistry: An international journal of biochemistry in medicine, 28(1), 19-26.

2 – Dørup, I., Skajaa, K., Clausen, T., & Kjeldsen, K. (1988). Reduced concentrations of potassium, magnesium, and sodium-potassium pumps in human skeletal muscle during treatment with diuretics. British medical journal (Clinical research ed.), 296(6620), 455.

3 – Tam, M., Gomez, S., Gonzalez-Gross, M., & Marcos, A. (2003). Possible roles of magnesium on the immune system. European journal of clinical nutrition,57(10), 1193-1197.

4 – White, R. E., & Hartzell, H. C. (1989). Magnesium ions in cardiac function: regulator of ion channels and second messengers. Biochemical pharmacology,38(6), 859-867.

5 – Okuma, T. (2001). Magnesium and bone strength. Nutrition, 17(7), 679-680.

6 – Paolisso, G., Scheen, A., d’Onofrio, F., & Lefèbvre, P. (1990). Magnesium and glucose homeostasis. Diabetologia, 33(9), 511-514.

7 – Sarrafzadegan, N., Khosravi-Boroujeni, H., Lotfizadeh, M., Pourmogaddas, A., & Salehi-Abargouei, A. (2016). Magnesium status and the metabolic syndrome: A systematic review and meta-analysis. Nutrition, 32(4), 409-417.

8 – Guerrero-Romero, F., & Rodríguez-Morán, M. (2009). The effect of lowering blood pressure by magnesium supplementation in diabetic hypertensive adults with low serum magnesium levels: a randomized, double-blind, placebo-controlled clinical trial. Journal of human hypertension, 23(4), 245-251.

9 – Song, Y., Li, T. Y., van Dam, R. M., Manson, J. E., & Hu, F. B. (2007). Magnesium intake and plasma concentrations of markers of systemic inflammation and endothelial dysfunction in women. The American journal of clinical nutrition, 85(4), 1068-1074.

10 – McCarty, M. F. (2005). Magnesium may mediate the favorable impact of whole grains on insulin sensitivity by acting as a mild calcium antagonist. Medical hypotheses, 64(3), 619-627.

11 – Rylander, R. (2014). Bioavailability of magnesium salts–a review. J Pharm Nutr Sci, 4(1), 57-9.

12 –  Steidl, L., & Ditmar, R. (1991). Osteoporosis treated with magnesium lactate. Acta Universitatis Palackianae Olomucensis Facultatis Medicae, 129, 99-106.

13 – Robinson, C. M., & Karet Frankl, F. E. (2017). Magnesium lactate in the treatment of Gitelman syndrome: patient-reported outcomes. Nephrology Dialysis Transplantation, 32(3), 508-512.

14 – Boyle, N. B., Lawton, C., & Dye, L. (2017). The effects of magnesium supplementation on subjective anxiety and stress—a systematic review. Nutrients, 9(5), 429.

15 – Felsby S, Nielsen J, Arendt-Nielsen L, Jensen TS. NMDA receptor blockade in chronic neuropathic pain: a comparison of ketamine and magnesium chloride. Pain. 1996;64:283–91.

16 – Uysal, N., Kizildag, S., Yuce, Z., Guvendi, G., Kandis, S., Koc, B., … & Ates, M. (2019). Timeline (bioavailability) of magnesium compounds in hours: which magnesium compound works best. Biol. Trace Elem. Res, 187, 128-136.

17 – Boulis, M., Boulis, M., & Clauw, D. (2021). Magnesium and Fibromyalgia: A Literature Review. Journal of Primary Care & Community Health, 12, 21501327211038433.

18 – McCarty, M. F. (1996). Complementary vascular-protective actions of magnesium and taurine: a rationale for magnesium taurate. Medical hypotheses, 46(2), 89-100.

19 – Institute of Medicine (IOM). Food and Nutrition Board. Dietary Reference Intakes: Calcium, Phosphorus, Magnesium, Vitamin D and Fluoride. Washington, DC: National Academy Press, 1997.

20 – Song, Y., Sesso, H. D., Manson, J. E., Cook, N. R., Buring, J. E., & Liu, S. (2006). Dietary magnesium intake and risk of incident hypertension among middle-aged and older US women in a 10-year follow-up study. The American journal of cardiology, 98(12), 1616-1621.

21 – Fogarty, A., Lewis, S. A., Scrivener, S. L., Antoniak, M., Pacey, S., Pringle, M., & Britton, J. (2003). Oral magnesium and vitamin C supplements in asthma: a parallel group randomized placebo‐controlled trial. Clinical & Experimental Allergy, 33(10), 1355-1359.

22 – Ceremużyński, L., Gębalska, J., Wołk, R., & Makowska, E. (2000). Hypomagnesemia in heart failure with ventricular arrhythmias. Beneficial effects of magnesium supplementation. Journal of internal medicine, 247(1), 78-86.

23 – Rude, R. K., Singer, F. R., & Gruber, H. E. (2009). Skeletal and hormonal effects of magnesium deficiency. Journal of the American College of Nutrition, 28(2), 131-141.

24 – Uwitonze, A. M., & Razzaque, M. S. (2018). Role of magnesium in vitamin D activation and function. Journal of Osteopathic Medicine, 118(3), 181-189

25 – Larsson, S. C., & Wolk, A. (2007). Magnesium intake and risk of type 2 diabetes: a meta‐analysis. Journal of internal medicine, 262(2), 208-214.

26 – Evert, A. B., Boucher, J. L., Cypress, M., Dunbar, S. A., Franz, M. J., Mayer-Davis, E. J., … & Yancy, W. S. (2014). Nutrition therapy recommendations for the management of adults with diabetes. Diabetes care, 37(Supplement 1), S120-S143.

27 – Dickinson, H. O., Nicolson, D., Campbell, F., Cook, J. V., Beyer, F. R., Ford, G. A., & Mason, J. (2006). Magnesium supplementation for the management of primary hypertension in adults. Cochrane Database of Systematic Reviews, (3).

28 – Champagne, C. M. (2006). Dietary interventions on blood pressure: the Dietary Approaches to Stop Hypertension (DASH) trials. Nutrition reviews, 64(suppl_1), S53-S56.

29 – Rude, R. K., Singer, F. R., & Gruber, H. E. (2009). Skeletal and hormonal effects of magnesium deficiency. Journal of the American College of Nutrition, 28(2), 131-141.

30 – Aydın, H., Deyneli, O., Yavuz, D., Gözü, H., Mutlu, N., Kaygusuz, I., & Akalın, S. (2010). Short-term oral magnesium supplementation suppresses bone turnover in postmenopausal osteoporotic women. Biological trace element research, 133(2), 136-143.