Magnesium is the fourth most abundant mineral in the body that plays an important role in over 300 enzymatic reactions.
Magnesium is a macromineral – this means our body requires large quantities of magnesium.
About 60% of the magnesium in your body is found in bone, while the rest is in muscles, soft tissues, and fluids, including blood.
The benefits magnesium offers to the body is not limited to one organ. It plays several important roles in the health of your body and brain.
Despite its importance, according to a study, 68% of Americans don’t meet the recommended intake of magnesium.
Magnesium deficiency is associated with a range of health complications, so it is essential to meet your magnesium requirements.
Magnesium Metabolism – Getting Technical
Distribution of Magnesium
About 60% of the magnesium is present in bone, 20% in skeletal muscle, 19% in other soft tissues, and less than 1% in the extracellular fluid (fluid outside the cells in the body). Magnesium is present in very low levels inside the cells except for situations like hypoxia (lack of oxygen) or extended periods of magnesium depletion.
Intestinal Absorption of Magnesium
When magnesium enters the body via dietary sources, about 30-40% of it is absorbed in the intestines. The factors that interfere with the absorption of magnesium haven’t been well-researched yet. According to a study, the parathyroid hormone (PTH) and vitamin D play a role in intestinal absorption.
Magnesium Reabsorption in the Kidney
Regulation of serum magnesium concentration is achieved mainly by control of renal magnesium reabsorption. 95% of the magnesium is reabsorbed in the kidney. The transport and reabsorption in the kidney are influenced by sodium chloride levels.
Magnesium reabsorption is increased in the kidney by parathyroid hormone and inhibited by hypercalcemia (high levels of calcium).
There are also certain genetic factors that influence the transport of magnesium into the kidney.
Importance of Magnesium
Scientists have been studying the effect of magnesium on health. This is what we know so far:
Magnesium Aids Biochemical Reactions
Magnesium is a cofactor (cofactors are chemical compounds that are required to activate enzymes) for more than 300 enzymes.
These enzymes are required for various chemical reactions that are involved in:
- Muscle movements
- Energy production
- Nervous system functioning
Magnesium Can Improve Brain Functioning
Magnesium is essential to communicate the signals from the brain to the rest of the body cells. The magnesium present in the receptor cells prevents unwarranted excitation of the brain cells, thereby preventing brain damage. Lowering of brain activity is also necessary to sleep.
Magnesium Can Lower Blood Pressure
Some studies suggest that magnesium consumption helps lower blood pressure. However, this effect was noticed only among people with high blood pressure (hypertensive). No effect was found on those with normal blood pressure levels.
Magnesium Can Improve Psychological Well-being
Since magnesium coordinates brain signals, it also keeps your mental health in check. Studies suggest a link between lower magnesium levels and depression.
Some studies also suggest that supplementing with magnesium can help alleviate symptoms of depression.Magnesium Can Enhance Exercise Performance
Magnesium is required to move blood sugar into cells, which gives the energy-boost during exercise. It is also required to remove the lactate from muscles, which causes fatigue.
A study suggests that magnesium needs rise by 10-20% when exercising than at rest.Magnesium Can Help Prevent Migraines
A study suggests that people with migraines are more likely to be magnesium deficient than others.
Some studies even encourage magnesium supplements to prevent and treat headaches.Magnesium Can Keep Your Heart Healthy
The contraction and relaxation of cardiac muscles are required for the beating of the heart – the muscles here follow a rhythmic contracting pattern. Calcium is required for muscle contraction, and magnesium is required for muscle relaxation. This helps in maintaining a steady heart rhythm.
Magnesium Can Maintain Blood Sugar Levels
The hormone insulin is required for the transport of sugar into the cells. Magnesium is required for insulin regulation. Any deficiency in this mineral can, therefore, increase your risk for type 2 diabetes.
Discovery of Magnesium
The name magnesium comes from Magnesia, a district of Thessaly/Greece where it was first found.
Even before magnesium was discovered as an element, it had already existed in everyone’s daily life.
In 1618, a farmer in England observed that his cows did not drink water from a particular well – he found that water from that well had a bitter taste. However, the same bitter-tasting water seemed to clear up scratches and rashes.
Eventually, the compound that gave the bitter taste was recognized as Epsom salts or magnesium sulfates (MgSO4).
In 1755, a Scottish physician Joseph Black recognized magnesium as a separate element.
However, it was isolated only in the 1800s by a British chemist Sir Humphry Davy. He also suggested the element to be named ‘magnium.’
In 1831, a French chemist Antoine A.B. Bussy discovered a way to isolate magnesium in large quantities. He published his findings in the journal “Mémoire Sur le Radical métallique de la Magnésie.
RDA of Magnesium
For adult men (aged 19 years and older), the RDA of magnesium is 400-420 mg. Adult women need lesser magnesium – 310-320 mg. For pregnant women 18 or older, the requirements are increased to 350–360 mg per day.
The daily upper intake level (highest levels of daily intake that doesn’t have any adverse health effects) for magnesium is 350 mg for anyone over eight years old, including pregnant and breastfeeding women.
How Does Genetics Affect Magnesium Requirements
TRPM6 Gene and Magnesium Requirements
The TRPM6 gene is located on chromosome 9 and encodes transient receptor potential cation channel subfamily M member 6 (TRPM6). This protein forms a channel that allows the flow of magnesium into the cells – it also allows the flow of small amounts of calcium into the cells.
The TRPM6 protein is primarily present in the large intestine, kidneys, and lungs. When the body requires magnesium, this channel allows the absorption in the intestine – when the body has excess magnesium, it filters out the magnesium ions into the kidneys to be excreted through the urine.
rs11144134 of TRPM6 Gene and Magnesium Deficiency Risk
rs11144134 is an SNP in the TRPM6 gene associated with the regulation of serum magnesium levels. According to a study, the T allele of rs11144134 in TRPM6 is associated with lower serum magnesium levels.
But the T allele was also associated with higher bone mineral density in the femoral neck and lumbar spine.
CASR gene and Magnesium Requirements
The CASR gene is located on chromosome 3 and encodes the ‘calcium-sensing receptor’ protein (CaSR). The protein is primarily present in the parathyroid gland, kidneys, and brain. The CASR gene is concerned mainly with maintaining calcium levels, but it also affects magnesium levels in the body. It especially regulates the reabsorption of magnesium in the kidneys.
rs17251221 of CASR Gene and Magnesium Deficiency Risk
rs17251221 is an SNP in the CASR gene associated with the regulation of serum magnesium levels. The presence of the G allele increases the serum magnesium levels.
Other genes like DCDC5, HOXD9, LUZP2, MDS1, MUC1, and SHROOM3 also influence magnesium requirements.
Non-genetic Factors That Influence Magnesium Levels
Hypomagnesemia – Magnesium Deficiency
- Type 2 diabetes: Excess blood sugar levels lead to increased excretion of magnesium through the kidneys
- Decreased absorption of magnesium in the gut due to gastrointestinal diseases
- Hypercalcemia (increased levels of calcium) lead to increased excretion of magnesium
- Alcohol dependence can lead to decreased dietary intake of magnesium
Hypermagnesemia – Excess Magnesium
- Renal failure: Malfunctioning kidneys can result in impaired excretion of magnesium
- Malnourishment
- Hypothyroidism
- Drugs containing magnesium, such as some laxatives and antacids
Symptoms of Hypomagnesemia
Some early signs of magnesium deficiency are:
- Loss of appetite
- Fatigue and weakness
- Nausea and vomiting
Untreated magnesium deficiency can lead to more severe symptoms like:
- Muscle contractions and cramps
- Coronary spasms
- Personality changes
- Numbness
- Seizures
- Hypokalemia (low potassium)
- Hypocalcemia (low calcium)
- Tingling sensation
- Abnormal or irregular heartbeats
Effects of Excess Magnesium: Hypermagnesemia
The symptoms of hypermagnesemia include:
- Hypotension – a very low blood pressure
- Decreased breathing rate
- Weakness
- Confusion and other neurological impairment
- Flushing
- Headache
- Decreased reflexes
Dietary Sources of Magnesium
Animal Sources of Magnesium
- Fatty fishes
- Plain yogurt
- Halibut
- Chicken breast
- Ground beef
Plant Sources of Magnesium
- Avocados
- Pumpkin seeds
- Almonds
- Spinach
- Soymilk
- Whole-wheat bread
- Lima beans
- Tuna
- Brown rice
- Dark chocolate
Summary
- Magnesium is an essential mineral that acts as a cofactor to over 300 enzymatic reactions involved in processes like energy production and nervous system functioning. It also plays a vital role in lowering blood pressure and enhancing your exercise performance.
- Magnesium is a macromineral – our body requires it in higher quantities. While adult males require about 400-420 mg of magnesium per day, adult women need to consume 310-320 mg per day.
- Even if you meet the RDA, certain conditions like diabetes, hypercalcemia, and alcoholism can prevent the mineral from being absorbed well by the body.
- TRMP6 is an important gene that is required for the transport of magnesium. The presence of the T allele in the SNP rs11144134 of this gene is associated with lower serum magnesium levels.
TheCASR gene, which is well known for its role in calcium metabolism, also influences the reabsorption of magnesium in the kidney – hypercalcemia leads to poor reabsorption of magnesium. - Lower magnesium levels can be identified with symptoms like nausea, fatigue, and loss of appetite. Magnesium toxicity is also harmful and manifests as hypotension, headache, and fatigue.
- Since magnesium is an essential mineral, it needs to be consumed through dietary sources. Some magnesium-rich foods include spinach, avocados, fatty fish, pumpkin seeds, soymilk, and lima beans.
Reference:
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