The human body relies upon several minerals to aid and support a variety of functions. Some minerals are classed as trace and are needed in small quantities, while others are classed as macro minerals and a higher intake is required.
Magnesium is a macro mineral and plays an important role on different aspects of your health. In this article we’ll take a closer look at magnesium and tell you all you need to know.
Magnesium function
Magnesium is required as a cofactor in over 300 enzyme reactions in the body – because of this, it has the ability to influence several areas of health.
It is involved in:
- Protein synthesis
- Regulation of blood pressure
- Energy production
- Blood sugar balance
- Bone development
- Muscle and nerve function, including muscle contraction and heart rhythm regulation
- Synthesis of glutathione – the body’s major antioxidant
- Synthesis of DNA and RNA
- Vitamin D and calcium balance
Magnesium sources
A variety of foods are rich in magnesium including dark green leafy vegetables such as kale and spinach, avocados, beans, almonds, cashews, Brazil nuts, pumpkin seeds, cacao and brown rice.
Optimal magnesium intake
The European Food Safety Authority (EFSA) set a recommended adequate intake (AI) for magnesium at 300mg per day for adults (1). The AI for children is as follows:
| Age | AI for magnesium |
|---|---|
| 7-11 months | 80 mg/day |
| 1-2 years | 170 mg/day |
| 3-10 years | 230 mg/day |
| 11-18 years | 250 mg/day |
These levels may be seen as the sufficient minimum intake required to prevent deficiency and health issues, rather than the optimal level. An optimal intake of magnesium may be higher and can be different according to your individual circumstances and health status.
Magnesium deficiency
Recently, a rise in cases of suboptimal magnesium levels has been reported. Your kidneys are responsible for regulating magnesium levels and preventing urinary losses if intake is low. True magnesium deficiency gives rise to numerous neurological or cardiovascular symptoms. As magnesium is required for so many enzyme actions, suboptimal levels may result in symptoms such as poor sleep, muscle cramps, tension, pain, high blood pressure, headaches, fatigue, anxiety and mood issues.
Factors that increase the chance of suboptimal magnesium status include:
- Kidney disease
- Gastro-intestinal problems that affect absorption – Crohn’s disease, coeliac disease, intestinal inflammation, post-surgery, prolonged diarrhoea
- Hormone and metabolic issues – diabetes, parathyroid gland disorders
- Medications that increase urinary losses of magnesium, such as diuretics
- Chronic alcoholism
- Stress
- Advancing age
- Intense or prolonged exercise
Testing magnesium levels
Magnesium is mostly found within the bones with the remainder in soft tissues, particularly muscle tissue. A very small percentage of magnesium is found in the blood and serum measurements to assess magnesium levels are generally not very useful as they do not truly reflect body magnesium levels. Measuring magnesium levels in red blood cells is seen by some as a better way to assess status, whilst others feel that a urinary tolerance test gives a better indication of magnesium utilisation in the body.
Toxicity and interactions
Excess magnesium does not seem to cause toxicity, as the kidneys are able to eliminate any excess through the urine, although the presence of kidney disease may limit this (2). Magnesium can stimulate the movement of the digestive tract and a high intake of magnesium may lead to diarrhoea or nausea. Some people are able to tolerate high levels whereas others are not.
Magnesium from dietary sources does not seem to have interactions with any medications but supplemental forms of magnesium may reduce the absorption of drugs such as bisphosphonates used in osteoporosis, anti-malarial drugs and digoxin.
Prolonged use of certain diuretics increases magnesium losses and chronic use of proton pump inhibitors, such as lansoprazole, may reduce magnesium levels. Tetracycline antibiotics may form complexes with magnesium, and should be taken at least 2 hours before or 4-6 hours after magnesium.
If you are taking any medication, you should consult a pharmacist or doctor before supplementing with a high dose of magnesium.
Magnesium and health
- Cardiovascular health
Cardiovascular health encompasses your blood pressure, cholesterol, triglycerides and arterial health. A single change, or combination of changes in these factors, may lead to poor cardiovascular health.
High blood pressure often shows no symptoms and is referred to as the ‘silent killer’. A higher dietary intake of magnesium has been found to give a reduced risk of developing high blood pressure (3). The effects of supplemental magnesium on blood pressure are mixed and some studies indicate a modest beneficial effect on high blood pressure (4).
Hypertension is a risk factor for the development of stroke, and a good dietary intake of magnesium reduces the risk of stroke by 8-11% (5).
A large study conducted on 90,000 female nurses spanning nearly 30 years highlighted there was almost a 40% lowered risk of fatal heart attack in women with the highest magnesium intake (6).
- Metabolic syndrome
Metabolic syndrome describes a collection of several health complaints that occur at the same time, including insulin resistance, high blood pressure, obesity and high blood fats like triglycerides or cholesterol. Metabolic syndrome is linked to the development of Type 2 diabetes and cardiovascular disease.
Studies have shown magnesium may play a role in the development of metabolic syndrome and individuals with a higher intake of magnesium may have over 30% lower risk of developing metabolic syndrome (7).
- Diabetes
Magnesium is needed not only for energy production but also for the production and action of insulin. Magnesium depletion has been associated with Type 1 diabetes, Type 2 diabetes and gestational diabetes and is also known to worsen insulin resistance.
There is no clear evidence explaining the link between low magnesium and blood sugar control issues; it may occur because of increased urinary losses in conditions like diabetes or the presence of insulin resistance.
Studies into the use of magnesium to support blood sugar control and insulin sensitivity are mixed and a 2016 meta-analysis concluded that magnesium supplementation showed more benefit in individuals with magnesium depletion than in those with good magnesium status (8).
- Osteoporosis
Calcium and magnesium are both essential minerals when it comes to bone formation, remodelling, strength and flexibility. As 60% of magnesium in the body is stored in bones, magnesium depletion may impact your bone health.
Lower levels of magnesium have been found in women with osteoporosis (9) and a higher dietary intake of magnesium is associated with better bone mineral density and reduced risk of fractures.
- Pain/migraine
Magnesium may block pain receptors in the brain and spinal cord and therefore may impact pain transmission (10). The inclusion of magnesium in pre- and post-operative medications shows pain scores are reduced following C-section and other surgery.
Low levels of magnesium are found in many migraine sufferers and depletion is linked to factors that may impact headaches, including constriction of blood vessels and neurotransmitter release (11). The use of magnesium for the reduction in frequency and severity of migraines is mixed and may show only a modest improvement in some individuals.
- Stress
Stress refers to pressures placed upon the body, either physical or psychological. The adrenal glands exert a variety of actions upon stimulation by stress and release several hormones that work to prepare the body for ‘fight or flight’. As your stress hormone cortisol rises, magnesium losses in urine are increased, leading to an increased need for magnesium and potential depletion (12).
Chronic stress is often associated with anxiety, which is also linked with low magnesium levels. Supplemental magnesium has been shown to increase resistance to stress and improve symptoms – the addition of vitamin B6 to magnesium has also shown improvements to stress (13).
- Pregnancy
Pre-eclampsia and eclampsia are serious conditions that can occur during pregnancy and are associated with dangerously high blood pressure and seizures. Although low levels of magnesium are seen in these conditions, and magnesium is included in medical treatment, there is little evidence to show that a reduced magnesium level is a causative factor in the development of pre-eclampsia or eclampsia (14).
- Gynaecological issues
Due to variations in hormones throughout the menstrual cycle it may be common for women to experience imbalances and symptoms associated with hormone changes.
It is estimated around 80-90% of women of reproductive age experience premenstrual syndrome (PMS), a collection of physical and psychological symptoms that can affect day to day life. Studies into PMS and magnesium show that magnesium levels may be low, and supplementation may benefit PMS symptoms. The addition of vitamin B6 also aids reduction in PMS symptoms.
Painful periods, also called dysmenorrhoea, are characterised by cramps before or during a period. Magnesium is thought to be of benefit by inhibiting contractions, therefore relaxing muscle tissue in the uterus.
Takeaway
Magnesium is an essential mineral and research indicates a large portion of the population may not have an adequate intake, leading to depletion. Addressing magnesium status is an important step on your journey to ensuring overall optimal health.
If you are experiencing any of the health issues discussed in this article or would like to know more about magnesium and the most bioavailable forms, a one to one consultation with an Amchara Personalised Health practitioner can help to guide you on the best course of action for your individual circumstances.
We’re dedicated to providing you with both insightful information and evidence-based content, all orientated towards the Personalised Health approach.
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