Magnesium is crucial for the healthy functioning of both our bodies and our minds. It is involved in over 300 different reactions in the body, including being used by every cell to build proteins, repair DNA and provide energy. Because blood levels of magnesium do not accurately reflect the amount of magnesium that is actually inside of the cells (more than 99% of total body magnesium is inside cells), most cases of magnesium deficiency are undiagnosed.
The vast majority of people in modern societies are at risk for magnesium deficiency because of chronic diseases, medications, decreases in food crop magnesium levels, and the availability of refined and processed foods. The loss of magnesium during food refining is significant: white flour (−82%), polished rice (−83%), starch (−97%) and white sugar (−99%). Since 1968, the magnesium content in wheat has dropped almost 20%.
Nearly two thirds of adults surveyed in the USA and England receive less than their minimum daily magnesium requirement. The mean intake of magnesium was 323 mg per day in men and 228 mg in women, and 10% of elderly women consumed less than 136 mg per day.
Research evaluating the nutrition of Paleolithic hunter/gatherer societies shows that on average, they were consuming 600mg per day! Our genetics and physiology is the same as our ancestors which means not only are we best adapted for these levels of magnesium, but we likely require more given the modern-day stressors that our bodies must keep up with.
According to research, most people require an additional 300 mg of magnesium per day in order to lower their risk of developing various chronic diseases. Even though the recommended daily allowance (RDA) for magnesium (between 320 and 420 mg/day for most people) may prevent frank magnesium deficiency, it is unlikely to provide optimal health and longevity, which should be the ultimate goal.
Here are some fast facts on magnesium:
The human body contains around 25 grams of magnesium
Magnesium is necessary for the functioning of over 300 enzymes in human body
90% of total body magnesium is contained in the muscles and bones (~27% and ~63%, respectively), 90% of which is bound and with only 10% being free
Only 1% of total body magnesium is found in serum and red blood cells
A normal serum magnesium level does not rule out magnesium deficiency because the body tightly regulates electrolyte levels in the blood; it tells us little of what is actually inside the cells and tissues
When intake is low, magnesium is pulled from the bone (as well as muscles and internal organs) in order to maintain normal blood levels, which predisposes to osteopenia, osteoporosis and fractures
Magnesium deficiency has been found in 84% of postmenopausal women with osteoporosis
Foods that use to be considered excellent sources of magnesium (like grains, greens and legumes) are estimated to have lost around 30% of this mineral due to modern farming practices
High cortisol (which means high stress levels) can deplete magnesium levels
Subclinical deficiency (a clinically silent reduction in physiological, cellular and/or biochemical functions) is more concerning than a frank deficiency because it's more difficult to diagnose, it can produce less obvious health effects (ie: calcification of the arteries) and it predisposes to numerous chronic diseases
Although serum potassium and serum magnesium values in patients receiving long-term treatment for high blood pressure are usually normal, muscle magnesium and muscle potassium levels are reduced in about 50% of these patients
Magnesium depletion is present in about 50% of all intensive care unit patients
More than 50% of those hospitalised with any of the following conditions are likely to be magnesium-deficient: hypertension, coronary artery disease, cerebrovascular event, gastrointestinal issues or alcoholism
6–12 weeks of strenuous physical activity can lead to magnesium deficiency
As mentioned, there are over 300 different enzyme reactions in the body that require magnesium. Here are some of the benefits of having sufficient levels of magnesium:
It is required in order to make ATP, and ATP acts as our main form of energy in every cell in our body, ultimately determining how energized we are
It helps to create, repair and protect DNA and proteins; without enough magnesium, protein production is impaired and this can have widespread consequences since we need protein for most of the structural components (including making antibodies to fight off infections) and nearly all metabolic functions in the body (enzymes are made of protein)
It sits inside cell membranes and helps in the transport of minerals into and out of cells, which aids in nerve signalling and muscle contraction (and why people with magnesium deficiency often get twitchy eye or muscle cramps, restless legs, or even hypertension)
It helps convert tryptophan into the neurotransmitter serotonin and also helps regulate dopamine and GABA which all play a role in anxiety and depression; it has also been shown to enhance the activity of antidepressant medications
It can bind to receptors in the brain that produce a calming effect which is why it can be a useful aid for sleep
It has a positive effect in the stress response, helping to modulate the amount of circulating cortisol in the body
The evidence in the literature suggests that subclinical magnesium deficiency is rampant and one of the leading causes of chronic diseases including cardiovascular disease and early mortality around the globe, and should be considered a public health crisis.
Stay tuned for updates on a complete list of the signs of deficiency and the different types of magnesium.
DiNicolantonio JJ, O’Keefe JH, Wilson W. Subclinical magnesium deficiency: a principal driver of cardiovascular disease and a public health crisis. Open Heart 2018;5:e000668. doi: 10.1136/openhrt-2017-000668
Wanli G., Hussain N., Zongsuo L., Dongfeng Y. Magnesium deficiency in plants: An urgent problem. The Crop Journal. Volume 4, Issue 2, April 2016, Pages 83-91.