Magnesium and Its Importance in the Human Body
Magnesium plays a vital role in numerous metabolic processes in the human body. Its functions are complex and closely related to bone physiology . It is also an essential cofactor in many metabolic reactions within the body . Regardless of gender, magnesium intake among the general population in Taiwan is generally insufficient. Deficiency of magnesium can lead to bone loss, which is especially critical for women at high risk of osteoporosis .
According to the National Nutrition and Health Status Survey report from 2013-2016, magnesium intake among the general population in Taiwan is generally insufficient. The following table illustrates population groups whose intake is below the Dietary Reference Intakes (DRIs) for magnesium: males aged 13 and above, females aged 13-64, and females aged 75 and above. Notably, the largest disparities are observed among males aged 13-15 and 16-18, with intake reaching only 71% and 67% of the reference intake, respectively. For females, those aged 13-15, 16-18, and 19-44 show greater disparities, with intake being only 62%, 60%, and 74% of the reference intake, respectively .
It is evident that magnesium intake is generally insufficient among the Taiwanese population, and the lack of magnesium can lead to bone loss . This insufficiency is particularly significant for women at high risk of osteoporosis.
What is “Magnesium”?
Magnesium is the fourth most abundant cation (Mg²⁺) in the body of vertebrates and is one of the essential minerals. Intracellularly, magnesium is the second most abundant cation after potassium. Both magnesium and potassium are crucial for many physiological functions . Approximately 99% of magnesium in the body is found in bone, muscle, and non-muscular soft tissues, with only 1% found in the blood . Magnesium is a primary component of bones and is mainly used for promoting bone growth and regeneration. However, the exact mechanisms of magnesium’s potential role in bone mineralization are not fully understood.
Research has found that magnesium plays a significant role in bone mineralization. Appropriate levels of magnesium can promote the mineralization of mesenchymal stem cells, while excess magnesium can harm bone formation . Additionally, magnesium serves as a cofactor in various metabolic reactions within the body and has different physiological functions inside cells. Imbalances in magnesium ions in the body can lead to conditions such as hypomagnesemia or hypermagnesemia, which may result in nervous, muscular, cardiac, or neurological disorders .
What are the Benefits of Magnesium?
Magnesium is one of the primary components of bones and affects the activity of osteoblasts and osteoclasts. It promotes bone growth, regeneration, and plays a significant role in bone mineralization . There is a growing body of research examining the impact of oral magnesium supplements on bone health. Clinical studies have found that postmenopausal women taking magnesium supplements for 30 days, in the form of magnesium citrate (1,830 mg/day), showed a significant increase in serum osteocalcin levels and a reduction in bone loss .
Another clinical study gave postmenopausal women daily oral magnesium supplements of either <206.5 mg or >422.5 mg. The group taking >422.5 mg showed a significant 3% increase in hip bone density (BMD) compared to the other group. Additionally, their whole-body bone density (BND) increased by 2% . This research indicates that magnesium supplementation can help reduce bone loss and enhance bone density in postmenopausal women.
Stabilizing Blood Sugar and Preventing Diabetes
Magnesium can act as a calcium antagonist in the body and protect vascular endothelial cells from oxidative stress. Low blood magnesium levels can lead to increased insulin resistance, affecting lipid metabolism and inducing oxidative damage to endothelial cells. This can contribute to the development of diabetes and its associated complications affecting both large and small blood vessels . There is a negative correlation between blood magnesium levels and insulin resistance, and lower intracellular magnesium concentrations can lead to defects in tyrosine kinase activity and alterations in insulin sensitivity. As a result, magnesium deficiency may contribute to insulin resistance .
Clinical research has found that oral magnesium supplements can help control blood sugar in patients with type 2 diabetes. After taking 250 mg of magnesium supplements daily for three months, the subjects showed significant reductions in glycated hemoglobin (HbA1C) levels and insulin concentrations compared to the control group. Therefore, magnesium supplements can improve insulin resistance and blood sugar control parameters (HbA1C) in diabetic patients .
Stabilizing Blood Pressure and Preventing Hypertension
Primary hypertension in humans is a complex, multifactorial condition. While the exact cause remains unclear, it primarily results from changes in blood vessel structure and function, leading to abnormal hemodynamics and increased peripheral resistance .
Modern research suggests that magnesium aids in lowering blood pressure. Oral magnesium can act as a natural calcium channel blocker, increase nitric oxide (NO) production in the body, improve impaired endothelial function, and stimulate both direct and indirect vasodilation, thereby reducing blood pressure. Magnesium can also enhance the effectiveness of antihypertensive medications. Daily magnesium intake of 500 mg to 1000 mg can reduce blood pressure by as much as 5.6/2.8 mm Hg .
Another study found that after four weeks of continuous daily supplementation with 300 mg of magnesium oxide, subjects experienced significant reductions in systolic and diastolic blood pressure .
Improving Sleep and Alleviating Anxiety
While the exact mechanisms of magnesium’s effects on neural function and sleep behavior are not fully understood, magnesium’s role in ion channel conductivity is crucial. Magnesium ions play a critical role in cellular neural transmission. Some studies suggest that magnesium has a role in regulating the excitability of the central nervous system. Magnesium supplementation is often considered as a way to improve sleep and alleviate insomnia, either as a standalone therapy or in combination with conventional medications .
Nearly 50% of the elderly population experiences insomnia, difficulty falling asleep, oversleeping, or waking up feeling unrefreshed. In one clinical study evaluating the efficacy of magnesium supplements in improving insomnia among the elderly, it was found that daily oral supplementation of 500 mg of magnesium for eight weeks led to significant increases in sleep duration, sleep efficiency, serum melatonin levels, and decreases in insomnia. This study suggested that magnesium supplementation can genuinely improve some cases of insomnia in the elderly .
Promoting Women’s Health
An increasing body of research suggests that magnesium deficiency may be associated with women’s health, such as preventing dysmenorrhea, premenstrual syndrome (PMS), menstrual migraine, and menopausal symptoms . Clinical studies have indicated that continuous magnesium supplementation for two months resulted in a significant reduction in premenstrual syndrome among the subjects . Additionally, in a study focused on leg cramps during pregnancy, it was found that daily oral supplementation of 300 mg of magnesium for four weeks improved the frequency and intensity of pregnancy-induced leg cramps. The magnesium supplement group experienced a significant 50% reduction in cramp frequency and intensity compared to the control group .
Recommended Daily Intake of “Magnesium”
According to the recommendations of the Health Promotion Administration of the Ministry of Health and Welfare in Taiwan, the daily recommended intake of magnesium for adults is 380mg for men and 320mg for women. Pregnant women are recommended to consume 350mg of magnesium per day . The U.S. FDA’s recommended daily intake of magnesium is 400-420mg for adult men and 310-320mg for adult women .
What Foods Can Be Consumed to Supplement “Magnesium”?
In general, magnesium is widely distributed in both plant and animal foods and beverages, and foods with dietary fiber can also provide magnesium. Dark green vegetables (such as spinach), dark-colored fruits, legumes, nuts, seeds, and whole grains are excellent sources of magnesium. However, some types of food processing, such as refining grains by removing nutrient-rich germ and bran, can significantly reduce magnesium content . In addition, tap water, mineral water, and bottled water can also be sources of magnesium, but the magnesium content in water varies depending on the source and brand, ranging from 1mg/L to over 120mg/L . In the diet, approximately 30% to 40% of magnesium can be absorbed by the body .
How to Effectively Supplement “Magnesium”? Is There a Specific Time for Consumption?
There are various forms of magnesium supplements, including magnesium oxide, magnesium citrate, and magnesium chloride, and different types of magnesium supplements are absorbed differently in the body. Magnesium forms that dissolve well in liquid are more readily absorbed in the intestines than those with lower solubility . There are essentially no restrictions on supplementation or specific times for supplementation; the key is to supplement regularly.
It is recommended to supplement calcium in addition to magnesium, as this can have a more beneficial effect on bone health. One study found that a 2:1 ratio of calcium to magnesium had the best effect on promoting bone cell adhesion, proliferation, and differentiation. This ratio also exhibited good cell compatibility, indicating that a 2:1 calcium-magnesium compound had a promoting effect on the proliferation of human bone cells . Therefore, supplementing calcium and magnesium together has more positive effects on bone health.
Are There Any Side Effects of “Magnesium”?
Consuming too much magnesium from food is not a health risk for healthy individuals because excess magnesium is excreted through the kidneys in urine. However, in cases of impaired kidney function, excessive magnesium intake may lead to hypermagnesemia due to reduced or impaired magnesium excretion by the kidneys . Nonetheless, excessive doses of magnesium in dietary supplements or medications can lead to diarrhea and may be accompanied by feelings of nausea and abdominal cramping.
Long-term excessive magnesium intake or magnesium toxicity can result in symptoms such as low blood pressure, nausea, vomiting, urinary retention, bowel obstruction, depression, drowsiness, and may progress to muscle weakness, difficulty breathing, extremely low blood pressure, and arrhythmias . Generally, as long as the daily intake falls within the recommendations provided by the Ministry of Health and Welfare, there is no need for concern regarding side effects of magnesium. The health benefits of magnesium for the body are numerous, and those in need of magnesium supplementation can refer to this information to better meet their nutritional requirements.