Our bodies require many minerals and nutrients to function properly. One important mineral is magnesium. Surprisingly, you may have heard little about its health benefits and why magnesium deficiency can promote so many problems. So, what exactly is magnesium and why is it so vital for our wellbeing? Here is a comprehensive guide to this magnificent mineral.
What Is Magnesium?
Magnesium is a chemical element found within human cells. You’ll also find it in plant matter, as a rock salt (magnesium carbonate) and as magnesium chloride which is found within the sea.
What Does Magnesium Do To The Body?
The human body is composed of elements that provide the foundations of tissues, fluids and factors that regulate how the body functions. Minerals like magnesium, calcium and potassium are required in large amounts.Adults have around 25g of magnesium present in their bodies with up to 60% in the bones alone. The rest is mainly found in soft tissues (1).
Magnesium is involved with over 300 biochemical processes in the body and assists in the growth of bones, nerves and muscle function, as well as helping to neutralise stomach acid. Furthermore, it aids the production of energy, the control of blood glucose levels, and cell formation.
How Much Magnesium Do We Need?
The recommended daily allowance generally depends on age. From food and supplements, a child aged 3 and under should consume 80mg of magnesium. Between 4 to 8 years, the amount rises to 130mg per day and between 9 to 13yrs, the daily intake is 240mg.
Between 14-18 years old, the intake for a female significantly increases to 360mg daily and at 19 to 30, you should be consuming 320 mg each day. Women aged over 31 and over require 310mg. Pregnant women require slightly more; between 350 to 400mg of magnesium is recommended daily.
Males need 400 to 420mg of the mineral each day, depending on age (2).
Recommended Daily Intake
3 and Under
4 to 8 years
9 to 13 years
14 to 18 years (Female)
19 to 30 years (Female)
31 and Over (Female)
350mg to 400mg
400 to 420mg
Signs Of Deficiency
A low level of magnesium is something that affects many and often goes undetected due to the difficulty in diagnosis. Normal levels of magnesium within the blood are generally 1.7 to 2.2 mg/dl. In cases where deficiency is present, this level is 1.7mg/dl and under (3).
There are several signs of magnesium deficiency and it normally affects the majority of functions within the body. These include;
Nausea is often one of the first signs of magnesium deficiency. This can appear in the form of morning sickness, vomiting, cramps or a poor appetite. Interestingly, even anorexia has been linked to low levels on magnesium within the body due to the weight loss associated with lack of appetite and sickness.
Decreased Energy Levels
Feeling tired, fatigued or run down is often a symptom of low magnesium levels. As magnesium is involved in over 300 enzyme reactions, it has a key role in many bodily functions, including the creation of energy. Magnesium is needed for the body to create and store energy that is required on a daily basis. When your body has sufficient levels of magnesium, a constant supple of energy is distributed, ensuring you feel active and refreshed. You have the energy to go about daily life in a positive manner without feeling exhausted and you can participate confidently in physical exercise. A recent study (4) signified that an increase in oxygen occurs during physical activity when magnesium levels are low. Even people with athletic ability use more energy than they would if their bodies had higher levels of magnesium.
Magnesium deficiency has long been associated with anxiety and depression (5). Magnesium essentially stops excess levels of calcium and glutamate, which are toxic to cells, from damaging neurons. When magnesium levels are low, this prevention decreases, meaning cells may eventually die.
When present in sufficient levels, magnesium suppresses a hormone called ATCH; the very hormone that causes the stress hormone cortisol and adrenaline to be released. Magnesium prevents such hormones entering the brain, thus, your reactions to stress, depression and anxiety are reduced. If there are limited amounts of magnesium within the body, your reactions are increased and as a result, you suffer from anxiety and mental health problems.
Studies (6) have indicated that increased magnesium levels assist in relaxation, helping you to sleep better. A reduction in mental health problems, such as anxiety also promotes a good night’s sleep. Low levels of magnesium are likely to increase insomnia, therefore, increasing fatigue and tiredness.
Magnesium deficiency can cause the muscles to become weak and stiff due to hyper responsive neuromuscular activity. This also results in muscle cramps.
Magnesium levels fluctuate during a menstrual cycle, especially towards the second half when magnesium levels rapidly plummet. High magnesium levels can aid symptoms of PMS, such as stomach cramps and headaches. In pregnant women, increased magnesium levels are required to limit the risk of preeclampsia and premature birth. Up to 400mg of magnesium is recommended each day for pregnant women.
Like calcium, magnesium is essential for strong, healthy bones. Magnesium aids the absorption of calcium and stimulates the production of calcitonin, which maintains a healthy bone structure. Magnesium also transforms vitamin D into an active form, preventing osteoporosis from occurring and promoting healthy bones. 60% of magnesium within the body is stored within the bones and transferred from the bone into the blood stream when needed. For this level of magnesium to be at optimum level, you should consume the recommended amount of magnesium daily.
Deficiency of Minerals
Minerals and nutrients work in combination to provide correct functioning within the body. Magnesium is essential for the consumption of a range of vitamins and minerals, including vitamin D and calcium. Without magnesium, these minerals are not correctly absorbed by the body, leading to a host of health problems.
High Blood Pressure
A low level of magnesium poses an increased risk of suffering with hypertension. Upping your intake of magnesium can help to reduce high blood pressure, however, studies have demonstrated that results can vary (7).
Low magnesium has been linked to heart problems (8). Magnesium transports calcium and without it, too much calcium inhibits cells which leads to heart problems. Excessive calcium levels are only one cause of heart disease, however, increasing your intake of magnesium assists with preventing blood clots and the calcification of arteries, helping to reduce the risk of having a heart attack.
Other Health Effects Of Magnesium Deficiency
Magnesium deficiency has also been linked to the development of diabetes (9), constipation, sensitivity to noise, poor co-ordination, headaches and allergies.
Who Is More At Risk?
Several people are more at risk from suffering from low levels of magnesium. These include;
Those Taking Medication
Certain types of drugs can reduce magnesium levels by promoting magnesium loss via excretion by the kidneys. Such drugs can include heart medication and birth control pills.
Those Drinking Caffeinated Drinks
As magnesium levels are largely controlled by the kidneys which excrete excess minerals, drinking caffeine drinks on a daily basis, such as tea and coffee, can promote increased levels of magnesium loss. This is because caffeine causes the kidneys to excrete more minerals.
Alcohol acts as a diuretic by increasing the excretion of magnesium. Studies have demonstrated that magnesium deficiency has been found in 30% of alcoholics (10).
Those Who Have Undergone Surgery
Stressful situations like surgery or other medical procedures can cause depleted magnesium levels. As these stressful situations require more magnesium to be used by the body, a deficiency can be triggered.
Those Consuming Carbonated Drinks
Dark coloured carbonated drinks contain phosphates which bind with magnesium in the body, making it unavailable for functional use. Drinking carbonated drinks on a regular basis will significantly reduce magnesium levels.
Those Who Consume Sugar
Refined sugar is another product that causes the kidneys to excrete more magnesium than necessary. Furthermore, sweet food contains no nutritional goodness, meaning if you consume large amounts, you’re likely to suffer from low levels of minerals and vitamins within your body.
Those Taking Calcium Supplements
If you have low levels of magnesium, calcium supplements can cause a reduction in absorption and retention. Interestingly, despite the effects calcium supplements can have on magnesium levels, magnesium supplements actually increase the use of calcium in the body. If you’re consuming calcium and magnesium joint supplements, consider at least a 1:1 ratio as this will help to improve bone health and reduce the risk of calcification in the arteries.
Older adults are likely to suffer from magnesium deficiency as ageing and poor health require higher levels of the mineral to be consumed. The body may also absorb and retain less magnesium as you grow older, meaning you need to intake larger amounts.
What Conditions Can Benefit From Magnesium?
Magnesium offers many health benefits, however, several conditions can benefit from high levels.
As magnesium assists with calcium absorption for healthier bones, consuming recommended daily amounts of magnesium can improve bone structure and help those suffering with osteoporosis.
Magnesium deficiency has been associated with an increased risk of developing diabetes (11). Magnesium aids carbohydrate metabolism and insulin activity to control blood glucose levels. Studies have demonstrated that with every 100mg of increase in the daily intake of magnesium, the risk of developing type 2 diabetes decreases by 15 percent (12).
Increasing your magnesium levels helps to reduce psychiatric issues like depression, anxiety, insomnia and migraines.
Increased magnesium levels can reduce the risk of having a stroke, abnormal heart rhythms and heart attack. It can also assist in regulating blood pressure, so consuming higher levels of magnesium is recommended for those suffering from heart disease.
What Foods Are Magnesium In?
Most people consume less than 250 mg of magnesium from food. However, several foods are rich in magnesium, including:
Amount per 100g Serving
Nuts and Seeds
Dark Leafy Greens
What To Do If You Think You’re Deficient?
As magnesium is so crucial for good health, it’s important to consume the recommended daily amount for your age and sex. It’s difficult to diagnose low levels of magnesium with precision, due to the fact that the symptoms of deficiency can be linked to many other heath conditions. Furthermore, only a low level of magnesium is present in the blood as the majority is stored in the bones. This makes it incredibly challenging to detect a deficiency and why low levels of magnesium are often considered to be an invisible heath condition.
Magnesium deficiency occurs in humans for many reasons. Crops suffer from lower magnesium levels due to soil depletion, magnesium is lost via regular bodily functions like muscle use and hormone production, and digestive problems can lead to low absorption rates. Thus, it’s no surprise that magnesium is the second most abundant element in the human body.
So, What Can You Do If You Think You’re Deficient?
If you’ve been suffering from one or more of the symptoms associated with magnesium deficiency, then it’s time to take action. Early signs of deficiency may include feeling sick, cramps, fatigue and headaches. Luckily, there are several things you can do to increase the magnesium levels in your body.
First, you need to increase your intake of foods rich in magnesium. Ensuring a balanced diet, with foods containing magnesium and limiting your intake of sugar, carbonated drinks and alcohol, which are known to decrease magnesium levels will improve your overall health. Furthermore, avoid consuming foods that are stripped of their magnesium content like refined, processed foods. You can also try consuming fermented food and drinks that contain prebiotics; good bacteria and yeast. These help the body to absorb more magnesium from the foods you eat.
Those with severely depleted levels of magnesium, in which vomiting, rapid heartbeat and low calcium levels can occur, can consider magnesium injections. Magnesium sulfate is often prescribed for hypomagnesemia, as well as an abnormal heart rhythm. It’s generally prescribed for adults to inject every six hours (4 doses) or administered as an IV drip over 3 hours, depending on the severity of the hypomagnesemia. However, magnesium sulfate injections do have side effects, including sweating, flushing, low blood pressure and lowered body temperature.
Who Should Supplement?
Magnesium supplements are an ideal method of effectively increasing your magnesium levels. As it’s hard to detect magnesium deficiency, it’s difficult to detect levels of the mineral in the body. The most common way is to measure serum magnesium concentrations in blood, though as the blood only contains a small amount of the magnesium present in your body, no test can be conclusive.
Many experts suggest that you should take supplements as there are little side effects from them (13). Regular supplementation will help to raise magnesium levels and promote good health, including reducing or eliminating any symptoms of deficiency that you may be suffering from. If you’re on medication, check with your doctor before using any supplement as they may counteract with each other.
There are varying forms of magnesium supplements and in general, the rate of absorption depends on the type you’re taking. Liquid is absorbed better as it is less soluble and its thought that forms of chloride, citrate and chelate are better absorbed by the body than magnesium supplements in sulfate or oxide form. The overall magnesium supplements you’ll generally find are:
- Magnesium Glycinate – Taken via a tablet or powder (mixed with juice or water), this supplement is easy to absorb by the body than many other forms and has very minimal side effects. It is recommended for anyone with magnesium deficiency.
- Magnesium Chloride Oil – This form of magnesium is perfect for anyone who doesn’t enjoy consuming oral supplements. Magnesium oil is applied over the skin. It is quickly absorbed as it bypasses the kidneys which eliminates much of your magnesium intake as waste. Magnesium chloride oil is suggested for those with digestion problems, who struggle to absorb the mineral from food. Some athletes also apply magnesium oil to heighten their energy levels and prevent muscle cramps.
- Magnesium Chelate – While this form of magnesium is found naturally in foods, in supplement form its job is to restore levels of the mineral within the body. It is easy to absorb and binds to amino acids.
- Magnesium Citrate – This form of supplement combines magnesium with citric acid. When taken in high doses, it may produce a laxative effect, but in regular doses, it helps to prevent constipation and improve digestion.
- Magnesium Threonate – This form has a high level of absorbability, however, it is not as available as other types of supplement.
- Ionic Magnesium – ionic magnesium is taken orally to ensure absorption is at maximum level. The body recognises magnesium in an ionic state easily,so it’snot required to be broken down by the stomach, therefore, increased absorption in the intestine takes place.
- You can also find magnesium in gel, bath flake or drink form, along with oil, tablets and powder.
How Much Magnesium Should I Take Per Day?
You should refer to the recommended daily intake for your sex and age when considering purchasing magnesium supplements. Everyone requires a different amount so this needs to be taken into consideration. For adult women, the required amount is on average 300mg, whereas for men, an average of 400mg is needed. Pregnant women need up to 400mg daily, while children require considerably less than adults.
The recommended daily amount is designed to be the minimal level needed to prevent deficiency occurring. Therefore, it is not necessarily the optimal level for your individual needs.
If you are an adult, start with a 300mg or 400mg (depending on whether you’re female or male) split into two doses and take one in the morning and one later on in the day (14). It’s best to follow the guidelines for your recommended daily amount to begin with.
If you suffer from deficiency, many experts suggest taking a higher dosage, though it’s best to see how your body reacts to the recommended amount first. Remember to take your diet into account, especially if you consume many foods rich in magnesium; this forms part of your daily intake.
You may get loose stools or an upset stomach to start with, however, this doesn’t mean that you’re consuming too much magnesium.
How Much Magnesium Is Too Much?
Magnesium overdose is rare. The body will naturally excrete magnesium via sweat, faeces and urine. An overdose is caused when the body cannot eliminate excess levels naturally. Those at risk of suffering from too much magnesium are those who suffer from regular constipation or are on dialysis.
If you’re suffering from confusion, extreme muscle weakness or slurring, you may have extremely high levels of magnesium in your body and will need to seek medical advice. The majority of people use magnesium supplements in safe levels. The elderly should be cautious when taking supplements as they may take the incorrect amount, and those with neuromuscular transmission disorders or atrial fibrillation should not take any magnesium supplement unless directed so by a doctor due to health risks.
Magnesium is an incredible mineral and one that has a major impact on our health and well-being. There are many symptoms of magnesium deficiency which often lie undetected. Knowing what to look out for and examining lifestyle or health factors relating to magnesium deficiency will help you to determine whether you need to use supplements.
A diet containing foods rich in magnesium, as well as supplementation,will increase levels of the mineral within your body and ensure that health problems are limited. A healthy, balanced lifestyle with lots of exercise, no smoking and cutting back on caffeine and alcohol will promote a healthier body and life.
10. Irwin R, Rippe J. Irwin and Rippe’s Intensive Care Medicine. Philadelphia: Lippincott, Williams and Wilkins; 2008.