Health benefits, deficiency, and sources
Magnesium is an essential element for the human body, and it plays a vital role in the nervous system’s healthy function, the homeostasis of bone metabolism. it regulates muscle functions, blood sugar levels, blood pressure, protein synthesis, and DNA processes. Insufficient dietary intake can cause troubles, and it is essential to keep a healthy magnesium balance to prevent diseases. The human metabolism cannot produce this mineral, which must come from food or supplements. It is present in many types of foods; mostly green plants are rich in this mineral. Chlorophyll, the natural pigment that allows plants to assimilate their molecules from carbon dioxide and light, contains a magnesium ion in the center of the molecule. Dietary supplements and specific medications, such as laxatives and antacids, also contain this mineral.
Required Daily Intake
The amount of magnesium one needs to take a day can differ. The daily requirement depends on age, sex, and physical activity. The average daily recommended amount for men is higher than for women; 400 mg for men and women 310 mg. Pregnant women generally need a little more magnesium, around 350 mg per day, but women need to reduce their intake back to the average amount during breastfeeding. From birth to 6 months old, the daily recommended amount is only 30 mg and 74 mg for 7-12-month-olds.
Magnesium has many different vital roles in human biochemical reactions. Most importantly, it is a cofactor in approximately 300 enzyme systems that regulate protein synthesis, blood pressure, muscle, and nerve function and controls blood glucose levels. It is essential for the body’s energy production and contributes to metabolic processes like glycolysis and oxidative phosphorylation. It is required for healthy bone development and is also responsible for the active transport of calcium and potassium through cell membranes, which is involved in the vital process of nerve impulse conduction, muscle contraction, and regulating normal sinus rhythm. Moreover, it contributes to the synthesis of DNA, RNA, and glutathione. The kidneys control magnesium homeostasis by regulating the excretion of minerals. Every day, the human body excretes 120 mg of this mineral into the urine per day, but this amount is lower in case of low intakes.
Health benefits of magnesium
Magnesium status plays an essential role in keeping the nervous system healthy, preventing cardiovascular disease, migraines, and type 2 diabetes. It contributes to various biochemical pathways. Therefore the lack of this mineral can result in many different ways. In this section, I will illustrate the health benefits of maintaining proper levels in the body.
Improving exercise performance
People who exercise a lot know that magnesium plays an essential role in muscle functions. During exercise, the body needs 10-20 % more of this mineral. Adequate levels can treat and prevent muscle cramps caused by high physical activity. It also helps to prolong lactic acid building up in the muscles, which causes fatigue.
Low magnesium levels are connected with inflammation, and proper supplementation can alleviate chronic inflammatory diseases. Some studies found that low levels and high CRP levels (a marker of inflammation) are correlated.
As magnesium is essential for healthy nerve function, it can also help with depression and regulating mood changes. Some studies had positive results and concluded that adequate levels could help reduce the symptoms of depression; however, there is a need for more research.
Improves PMS symptoms
Magnesium is proved useful in reducing the symptoms of premenstrual syndrome, PMS. It can reduce water retention, improve mood, and reduce tiredness and irritability.
Preventing cardiovascular disease
Cardiovascular diseases are mainly caused by high blood pressure as known as hypertension. Magnesium plays a vital role in regulating heart rhythm, and this fact provided a solid base for research investigating its effects regarding hypertension. Studies showed that keeping a sufficient level of magnesium, however, can lower the blood pressure to some extent. The studies included people with diets rich in this mineral or people with supplements. However, the results are not definitive because other minerals, such as calcium and potassium, can also reduce systolic and diastolic blood pressure. Therefore the findings cannot be independent of other nutrients. Other studies concluded that proper magnesium dietary intake could lower the risk of sudden cardiac death. The risk of developing ischemic heart disease is significantly lower when one takes higher levels as a supplement, around 250 mg/ day.
Type 2 diabetes and magnesium
People following a magnesium-rich diet have a lower risk of developing type 2 diabetes. This reduced risk is most likely due to the vital role magnesium plays in the metabolism of glucose. Moreover, critically low levels of this mineral or hypomagnesemia can result in insulin resistance, which can be a predecessor to diabetes. Type 2 diabetes affects the excretion of magnesium into the urine, and it can also cause a deficiency, which worsens the status of diabetes. Research studies support magnesium’s importance regarding diabetes prevention. However, many of these studies have purely found a correlation between magnesium levels and the risk of diabetes, which is not sufficient proof for a causal relationship. According to the American Diabetes Association, there isn’t enough evidence to prove that glycemic control will also improve in diabetic people by improving serum levels.
Osteoporosis and magnesium
Magnesium contributes to healthy bone formation and impacts osteoblasts, the cells that synthesize bone cells and osteoclasts, which break down bone tissue. It indirectly affects bone metabolism and acts as the parathyroid hormone and vitamin D, responsible for regulating the calcium levels of the bone and normal bone function. Osteoporosis patients tend to have lower levels than healthy ones; some studies also indicate that magnesium deficiency is a risk factor for developing the disease. Supplementation can increase bone mineral density, which can become more critical at older ages.
Magnesium deficiency and frequent headaches can be linked; therefore, supplementation can bring relief. People with migraine headaches usually have lower levels of magnesium in the blood. Some studies suggest that taking a sufficient amount of this mineral can prevent migraines when applied long-term.
Sources of magnesium
Magnesium is present in many different types of food; specific plants, animal-derived products, and beverages are rich in this mineral. If a vegetable contains chlorophyll, then it is rich in magnesium. Hence, leafy greens are high in this mineral, such as spinach, cabbage, and lettuce. Legumes, nuts, seeds, and whole grains are also excellent sources . Spices, cereals, and cocoa are also rich sources, as well as tea and coffee.
Another rule of thumb is that if the food contains dietary fiber, it is rich in magnesium. Some fortified food and beverage contain a high amount of this mineral, for example, cereals and energy drinks. Mineral water is also a good source of minerals in general. However, the amount of magnesium in a bottle can vary by brand, and it can range from 1.0 mg/ L to 120 mg/ L. It is essential to point out that the gut absorbs only 30-40% of magnesium consumed.
Several forms of supplements can boost the magnesium status and bring back the body into balance. The most common supplementation forms are oxide, citrate, chloride, lactate, and glycinate. These supplements differ in inefficiency because the body has a specific capacity to absorb them. Recent studies show that citrate and glycinate has the best bioavailability. The absorption also depends on whether it can dissolve in liquid; if the supplement has consistency and dissolves in liquid, it will be more effectively absorbed by the gut.
Medications that contain magnesium
In some medications, there are high amounts of magnesium. Laxatives can contain high concentrations of this mineral, although the gut does not absorb most of it because of the laxative effect. Antacid medications for heartburn can also contain this mineral. The interference of these medications with magnesium balance is well-known, and pharmaceutical companies have developed magnesium-free alternatives.
Magnesium deficiency is rare, but several conditions (including unhealthy nutrition) can result in inadequate levels. Vegetables are a primary source; therefore, a healthy diet contributes to avoiding a deficiency. The diagnosis of a deficiency is based on serum levels. However, this diagnosis can be challenging because most of this mineral is in the bones or the cells. Therefore, serum levels do not necessarily give a full picture of the total level in the body or specific organs. Still, they can provide a reasonable estimate of whether the patient needs supplementation or not. Serum levels within the normal range but close to the minimum can indicate sub-deficiency. Other tests include measuring magnesium concentration in saliva, urine, blood, or erythrocytes and performing a tolerance test. Even though none of the abovementioned methods are accurate enough and all of the methods can show unsatisfactory results in many cases, the most reliable considered to be the tolerance test.
Signs and symptoms
Signs and symptoms of mild magnesium deficiency include loss of appetite, severe fatigue and muscle weakness, nausea, and vomiting. In more severe cases, it presents with muscle cramps, numbness, and an uncomfortable tingling feeling, seizures, involuntary muscle contractions, coronary spasm, abnormal sinus rhythm, and personality change due to the abnormal function of the nervous system.
Who is at a higher risk of deficiency?
People with different health conditions can develop magnesium deficiency more easily. The most apparent reason for inadequate levels of this mineral is insufficient daily intake. However, some people cannot absorb the magnesium properly through the gut. The latter can be due to a medical condition or a prescribed medication. In the following, we can see examples for these.
Kidney disease resulting in kidney malfunction can cause magnesium deficiency. When the organ isn’t functioning correctly, more magnesium can be excreted into the urine than needs to, and it causes low levels of minerals.
The levels of parathyroid hormone depend on the magnesium levels and vice versa. Parathyroid hormone production and secretion are regulated by a negative feedback loop, which means that low blood levels initiate parathyroid hormone production. On the other hand, if the homeostasis of the parathyroid hormone is disturbed, it can cause magnesium deficiency.
People with gastrointestinal diseases, such as Crohn’s disease, regional enteritis, or celiac disease, have a higher risk of developing insufficient levels of magnesium. In these people, chronic fat malabsorption and diarrhea and the special diet these malfunctions require can cause magnesium depletion.
Type 2 diabetes
Inadequate magnesium levels can happen due to high urinary excretion in type 2 diabetes or insulin resistance. Magnesium deflates from the body with high levels of glucose because of the malfunction of the pancreas. The disease causes an increased kidney excretion that results in lower levels in the blood.
Chronic alcoholism can cause an excessive loss of magnesium, which is a prevalent cause of the deficiency. In this case, low dietary intake and poor nutrition can cause magnesium depletion. Severe cases of alcoholism, frequent vomiting, diarrhea, or steatorrhea may also cause a deficiency. Other potential causes include renal dysfunction, phosphate depletion, hyperaldosteronism, acute alcoholic ketoacidosis, or vitamin D deficiency. In the presence of liver damage due to chronic alcoholism, magnesium deficiency occurs as a secondary condition.
Older people are also prone to have a magnesium deficiency, which can be caused by three reasons. First of all, gut absorption capacity is usually decreasing with age, and above 60 years of age, there is a higher risk of causing a severe magnesium deficiency. Second, older people may take medications that inhibit absorption to some extent, which causes the deficit. Third, they are also more likely to have other chronic diseases such as type 2 diabetes that interferes with magnesium intake.
People who take specific medicines
Magnesium status can easily be affected by specific medications and cause a low level of this mineral called hypomagnesemia. Some antacids are proton pump inhibitors intended to treat acid reflux. However, as a side-effect, it can excessively lower magnesium levels of the body. Examples of proton pump inhibitors are dexlansoprazole (Dexilant), esomeprazole (Nexium), pantoprazole (Protonix), omeprazole (Prilosec, Zegerid), rabeprazole (Aciphex), and lansoprazole (Prevacid). Usually, the doctor prescribing any of these medications should check the patient’s magnesium level with a blood test. Some laxatives also have the same effect as they reduce nutrient absorption in general. Therefore, when someone is taking laxatives regularly, consider taking a break to avoid nutrient absorption problems. Some supplements containing high levels of zinc can also disrupt the bioavailability of magnesium.
Moreover, certain bisphosphonates can interfere with magnesium supplements. Alendronate (Fosamax) is a bisphosphonate that treats osteoporosis, and it is recommended not to take the supplements simultaneously as they have antagonist effects. Medication for diuretics can also decrease the magnesium levels in the blood as it induces the kidneys to excrete a higher amount of magnesium. The loss can result in a deficiency. These medications include furosemide, bumetanide hydrochlorothiazide, and ethacrynic acid. Furthermore, certain types of antibiotics and magnesium can form insoluble complexes that dramatically lower magnesium’s bioavailability. Therefore, tetracyclines and quinolone antibiotics should be taken 2 hours before the supplement.
Therapy for magnesium deficiency
Severe cases of deficiencies require intravenous injections. People with arrhythmia usually take injections. Oral supplementation is sufficient to prevent migraines or to keep a healthy level of this mineral. If hypomagnesemia is caused by alcoholism, oral intake can reverse the effects, although some cases require parenteral administration.
It is unlikely to excessive levels of serum magnesium from only food sources. Healthy kidney function ensures that the excretion of surplus in the urine. On the other hand, supplements and medicines can cause diarrhea, nausea, abdominal pain, and cramps. Extreme amounts can lead to depression, muscle weakness, breathing difficulties, irregular heart rhythm, and eventually cardiac arrest and heart failure. High serum levels cause toxicity that can make dialysis necessary. It can be impaired with decreased kidney function because a healthy kidney can excrete most of the excess magnesium. Therefore, supplementation shouldn’t go over the recommended limit.
Regarding excessive amounts, not every form of supplement has the same risk. Magnesium carbonate, chloride, oxide, and gluconate are more likely to cause diarrhea because these are difficult for the body to absorb. In this case, the unabsorbed salts work as a powerful laxative effect.