Magnesium and Fever


Winters are hard in the UK, and we often see an increase in people visiting their GP or the hospital, presenting with fever. This had compounded during  the era of COVID-19 epidemic. This has elicited a new search interest for alternative remedies for fever and associated symptoms. Magnesium has been used in medicine for over 300 years, so that it is considered by  many to have been introduced in the late 1600’s.1

Recent studies have shown how important magnesium is for bolstering and maintaining the immune system, thus allowing for a potentially new therapeutic use of magnesium.


Magnesium, also commonly symbolised as Mg, is one of the most important nutrients that our bodies require as it is involved in many biological processes that include over 300 enzymatic reactions in our body to achieve such essential tasks as building bones, maintaining blood sugar levels and regulating muscle and nerve function.

There are many different forms of magnesium that can be used internally or externally. The 3 most commonly used forms of magnesium are magnesium sulphate, magnesium salicylate and magnesium citrate all of which are used in  various ways. The Epsom Salt Council states  that magnesium sulphate can be used externally, in the form of inexpensive Epsom salts, to help reduce muscle pain, soreness and speed up recovery from injury. Magnesium sulphate supplementation is used internally as therapy for magnesium deficiency, Torsades de Pointes arrhythmias, asthma, and a pregnancy complication called Eclampsia. Most of the magnesium sulphate used medically is administered intravenously, however, it can be given orally or intrathecally. Magnesium salicylate is used as a nonsteroidal anti-inflammatory drug (NSAID) to help relieve moderate muscle pain.

Magnesium citrate is the main  form of magnesium found in over the counter magnesium supplement. The other common form of magnesium found in supplements is magnesium oxide, which is, however, less bioavailable, i.e., less is absorbed and processed by the body.2

However, roughly 30-40% of the dietary magnesium we consume is absorbed. The National Institute of Health (NIH) have set the Recommended Daily Allowance (RDA) for magnesium as approximately 400-420 mg for adults assigned male at birth (AMAB) and 310-320 mg for adults assigned female at birth (AFAB), with pregnant individuals  having a slightly higher intake value of between 350-360mg.

Magnesium can be found in a wide range of plants, animal foods and beverages. Good sources of magnesium include leafy green vegetables, such as spinach, nuts, whole grains, seeds, and legumes. Often many breakfast cereals and processed foods are fortified with magnesium.

Food (Serving)Milligrams per serving
Pumpkin seeds, roasted (29 grams)156
Chia seeds (29 grams)111
Almonds, dry roasted (29 grams)80
Spinach, boiled(100 grams)78
Cashews, dry roasted (29 grams)74

Table 1: Top magnesium food sources. (needs a reference)

Milk and dairy products are key sources of magnesium, especially for children where they  account  for 10-30% of their total magnesium intake.

If the RDA of magnesium is not met through dietary intake, it can be supplemented as magnesium citrate.

In addition to its fever combatting effects, studies have shown that magnesium can help to lower high blood pressure (hypertension), thus, reducing the risk of heart disease and stroke.3

Magnesium and Vitamin D

Vitamin D is currently the most hyped supplement on the market, but what does it actually do?

It has been at the center  of research regarding its positive impact on various body systems, like bone health, insulin control, heart health, reducing the susceptibility to cancers and even helping to prevent the more severe consequences of COVID-19. However, although it is known as the “wonder vitamin”, it cannot work alone, which is demonstrated by the complex interrelation between it and magnesium allowing both   to maintain a healthy body. Essentially, magnesium makes vitamin D bioavailable to be used in the body. Without magnesium, vitamin D is simply stored.

Effects (good and bad) of magnesium on fever

Magnesium as a treatment for fever, also known as pyrexia, is currently an area of interest to many.  Recent research into magnesium has shown that it bolsters our immune system’s ability to tackle pathogens, which causes us to develop  fever. Magnesium also enhances the ability of the immune system to  fight cancerous cells.

Additionally, a study by the American Society of Anaesthesiologists has shown  how magnesium (sulphate) can be used as a protective agent during  labour to reduce the risk of  delivering ladies developing fever, 4,5 which can lead to complications in new-borns.

However, as with any mineral in our bodies, too much or too little magnesium can cause issues. Dietary deficiencies of magnesium may be a cause  of metabolic syndrome, anxiety, skeletal muscle loss, confusion and even delirium.

Although research is leaning towards the use  of magnesium for treating fever, or as  a supplement to treat magnesium deficiency, the fact that high doses of magnesium (leading to hypermagnesaemia) can cause nausea, abdominal cramping and diarrhoea should not be dismissed. 


Magnesium is a very important mineral within the human body and has been shown to have many positive effects in various bodily systems, which highlights  how essential it is that we should try to meet the recommended daily amount. Nonetheless, when given in excess, it can also cause problems , some which may be irreversible. Magnesium comes in different forms, of different indications, so  in case you need a magnesium supplement, please, contact your healthcare provider to receive medical advice regarding which form to use, how long you use it, and what side effects you may worry about.


  1. Durlach J. Overview of Magnesium Research: History and Current Trends. New Perspectives in Magnesium Research. 2007;3–10.
  2. Firoz M, Graber M. Bioavailability of US commercial magnesium preparations. Magnesium Research [Internet]. 2001 Dec 1;14(4):257–62. Available from:
  3. Dickinson HO, Nicolson D, Campbell F, Cook JV, Beyer FR, Ford GA, et al. Magnesium supplementation for the management of primary hypertension in adults. Cochrane Database of Systematic Reviews [Internet]. 2006 Jul 19; Available from:
  4. American Society of Anesthesiologists (ASA). Magnesium during labor may reduce risk of fever in mothers and complications in babies [Internet]. ScienceDaily. 2015 [cited 2022 Dec 19]. Available from:
  5. Lange EMS, Segal S, Pancaro C, Wong CA, Grobman WA, Russell GB, et al. Association between Intrapartum Magnesium Administration and the Incidence of Maternal Fever. Anesthesiology. 2017 Dec 1;127(6):942–52.
This content is purely informational and isn’t medical guidance. It shouldn’t replace professional medical counsel. Always consult your physician regarding treatment risks and benefits. See our editorial standards for more details.

Get our health newsletter

Get daily health and wellness advice from our medical team.
Your privacy is important to us. Any information you provide to this website may be placed by us on our servers. If you do not agree do not provide the information.

Judith Molanza

Bachelor of Medicine, Bachelor of Surgery - MBBS, Medicine, University of Nottingham

Judith is a Graduate Entry Medical student who decided to embark on a career in medicine after complete img her BSc in Medical Physiology. She is a budding talented writer with a keen interest in holistic wellness topics.
Judith hopes to educate and inform others about the importance of maintaining good health, and to inspire people to make positive changes in their lives.

Leave a Reply

Your email address will not be published. Required fields are marked * presents all health information in line with our terms and conditions. It is essential to understand that the medical information available on our platform is not intended to substitute the relationship between a patient and their physician or doctor, as well as any medical guidance they offer. Always consult with a healthcare professional before making any decisions based on the information found on our website.
Klarity is a citizen-centric health data management platform that enables citizens to securely access, control and share their own health data. Klarity Health Library aims to provide clear and evidence-based health and wellness related informative articles. 
Klarity / Managed Self Ltd
Alum House
5 Alum Chine Road
Westbourne Bournemouth BH4 8DT
VAT Number: 362 5758 74
Company Number: 10696687

Phone Number:

 +44 20 3239 9818