Author – Phoebe Chan – BSc (Hons) Nutrition and Human Health
Magnesium is a mineral the human body needs to function properly. It’s especially important for a healthy cardiovascular system, nerves, muscles and bones. It also helps regulate the body’s calcium and blood sugar levels. The importance of magnesium is well known, but is usually the forgotten electrolyte. The reason for this is because people don’t usually experience any symptoms of deficiency until levels are really low (1). This blog will cover the functions, benefits, requirements and sources of magnesium.
What is Magnesium?
Magnesium is a mineral and electrolyte that is important for normal bone structure in the body. It assists more than 300 enzymes in carrying out various chemical reactions in the body such as protein synthesis and bone formation, and regulating blood sugar, blood pressure and muscle nerve function. Low levels are associated with osteoporosis, high blood pressure and stroke.
More than half of the magnesium in the body is stored in our bones. The remainder is stored in various tissues throughout the body (2).
Key Functions of Magnesium
Energy Production
ATP is the universal energy currency of cells, a molecule that stores and releases the energy required for nearly all biological processes. Magnesium is an essential cofactor for hundreds of enzymatic reactions involved in the process of cellular respiration, through which glucose, fatty acids, and amino acids are converted into usable energy. It stabilises the ATP molecule, allowing it to function properly. Without enough magnesium, the metabolic pathways leading to ATP production become inefficient, consequently slowing down or disrupting cellular respiration. This can result in reduced energy production and fatigue (3).
Muscle Function and Relaxation
Spasms are painful muscle contractions, and one of magnesium’s functions within the body is to prevent them. It does this by balancing calcium activity within muscle cells. While calcium triggers muscle contraction, magnesium helps muscles relax by regulating calcium movement and supporting ATP-dependent processes.
Calcium and magnesium act in opposition as they bind with the same proteins in the muscles. A build up of calcium causes muscles to over-contract, leading to spasms or twitches. Magnesium regulates these contractions and allows the muscles to relax, which is why some health professionals advise increasing intake to alleviate and prevent spasms (4).
Nervous System Regulation
Magnesium helps regulate nerve signalling and brain function in the central nervous system (CNS). It plays a key role in controlling the activity of nerve cells, preventing over-excitation that can contribute to stress, restlessness, and nervousness. While the hypothalamus and pituitary gland control stress hormones released by the adrenal glands, magnesium supports these signalling pathways, helping the body respond to stress. However, if the magnesium reservoir is emptied due to chronic stress, stress resistance is reduced (5).
Heart Health
Magnesium plays an important role in the cardiovascular system, and together with calcium, is involved in heart cell function and blood pumping (6).
Whilst the heart is pumping, the electrical impulse then moves towards the centre of your heart, where it meets the atrioventricular or AV node. Magnesium helps maintain stable electrical activity in the heart cells by regulating the movement of calcium and potassium across cell membranes.
When magnesium levels are too low, the heart can become more electrically excitable, which may contribute to irregular heart rhythms or palpitations. Adequate magnesium intake helps support a steady, well-coordinated heartbeat and overall cardiovascular health (7).
Bone Health
When people think about bone health, calcium and vitamin D usually get all the attention. While both of these are essential, magnesium is also important for bone health that often gets overlooked. Magnesium contributes to bone strength in several interconnected ways:
- Improves Bone Structure: magnesium helps form the crystal structure of bone. Without adequate magnesium, bones may become more brittle, even if calcium intake is high.
- Regulates Calcium Balance: magnesium helps control how calcium is transported and deposited in the body. Too little magnesium can lead to calcium being poorly absorbed or deposited in soft tissues instead of bones.
- Activates Vitamin D : vitamin D must be converted into its active form to help absorb calcium – and magnesium is required for this activation. Low magnesium can make vitamin D supplements less effective.
- Reduces Low–Grade Inflammation: chronic, low-level inflammation has been linked to bone loss. Magnesium helps regulate inflammatory markers, which may indirectly support bone health (8).
Blood Sugar and Metabolic Support
Some evidence suggests that higher magnesium intake is linked to a lower risk of diabetes . This is likely because magnesium helps break down sugars and decrease insulin resistance (9).
One study evaluated whether magnesium supplementation can improve blood sugar control in people with type 2 diabetes. It was found that daily magnesium supplements improved insulin sensitivity by 10% and lowered blood sugar levels by 37% (10).
Daily Magnesium Requirements
The maximum recommended daily dose of magnesium for adults is 420 mg for males and 350 mg for females. However, different factors may influence our required dose such as age and health conditions. The table below shows the recommend daily allowance (RDA) or adequate intake (AI) of elemental magnesium for infants, children and adults:
For people over 18 years of age who are pregnant, the requirements are increased to 350-360mg per day (11).
Conclusion
Magnesium is an essential mineral in the body, which plays a critical role in maintaining overall health. It supports the cardiovascular system, nerves, muscles and bones, whilst also contributing to energy production and nervous system regulation. Since magnesium is involved in over 300 biochemical reactions in the body, it is vital we reach the RDA. Adequate intake can benefit long-term health and help support metabolic balance, bone strength and cardiovascular wellbeing.
FAQ’s (Frequently Asked Questions)
What does magnesium do in the body?
Magnesium is involved in over 300 biochemical reactions in the body. It supports energy production, muscle contraction and relaxation, nerve signalling, blood sugar regulation, heart rhythm, and bone structure.
How much magnesium do I need per day?
The Recommended Daily Allowance (RDA) varies by age and sex. Adult men aged 19–30 require about 400 mg per day, while men over 31 require 420 mg. Adult women aged 19–30 need approximately 310 mg daily, and women over 31 need 320 mg. Requirements may increase during pregnancy and breastfeeding.
What are the benefits of magnesium?
Magnesium supports heart health, helps maintain strong bones, improves muscle function, regulates blood sugar levels, supports healthy nerve function, and may help reduce low-grade inflammation.
References
- https://pmc.ncbi.nlm.nih.gov/articles/PMC6524065/
- https://nutritionsource.hsph.harvard.edu/magnesium/
- https://www.benatur.eu/en/2024/07/22/magnesium-for-energy/
- https://www.body-evolve.co.uk/why-is-magnesium-good-for-the-muscles/
- https://www.denk-nutrition.de/en/guidebooks/magnesium-all-rounder-for-muscles-nerves-heart-bones/
- https://futureyouhealth.com/blogs/knowledge-centre/magnesium-definitive-guide
- https://health.clevelandclinic.org/magnesium-for-heart-palpitations
- https://ubiehealth.com/doctors-note/magnesium-menopause-bone-densities-osteoporosis-9321e2
- https://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/
- https://www.mdpi.com/2072-6643/11/1/44
- https://www.healthline.com/nutrition/magnesium-dosage#supplements
