Magnesium is a fundamental mineral essential for life, involved in over 380 biochemical reactions within the body. This includes ATP production in mitochondria, protein synthesis, and maintaining DNA integrity. On average, a 70 kg individual retains between 25-30 grams of magnesium, with approximately 55% located in the bones, 25% in muscles, 19% in soft tissues, and only 1% in the bloodstream. Consequently, blood tests do not provide an accurate reflection of overall magnesium levels, and it is estimated that nearly half of the population fails to consume adequate amounts.

Potential Deficiency and Its Implications

Several disorders can reduce magnesium availability, such as diabetes, gastrointestinal issues, the use of medications like omeprazole, and episodes of stress. Symptoms of magnesium deficiency may include fatigue, muscle spasms, cramps, headaches, arrhythmias, and sleep difficulties. Furthermore, low magnesium levels can contribute to various chronic, silent disorders, manifesting over time, such as osteoporosis, metabolic problems, cardiovascular disease, and depression.

In this article, we will explore the primary issues related to magnesium deficiency, how to obtain adequate magnesium through diet, and the best magnesium supplements available.

Cardiovascular and Metabolic Health

Magnesium plays a crucial role in muscle contraction, including that of the heart. Adequate magnesium levels are associated with a reduced risk of cardiovascular disease . Magnesium deficiency increases insulin resistance, further reducing magnesium absorption, creating a vicious circle (Reference: Nutrition Journal). Each additional 100 mg of magnesium per day is linked to a 10% lower risk of type 2 diabetes and a 20% lower risk of heart failure . Magnesium also aids the inflammatory response; low levels can heighten chronic inflammation, contributing to multiple diseases.

Magnesium, Bones, and Muscles

Magnesium is the third most abundant mineral found in bones, after calcium and phosphorus. It participates in bone mineralisation and acts as a reservoir for releasing magnesium when needed. Increased magnesium intake correlates with improved bone density (Review). Moreover, magnesium is essential for activating vitamin D, another compound critical for skeletal health.

Intense exercise elevates magnesium requirements as it assists glucose uptake by muscles and lactate recycling. Therefore, supplementing with magnesium may enhance performance and mitigate muscle damage, particularly in individuals with low magnesium status (Meta-analysis).

Magnesium, Depression, Stress, and Sleep

Magnesium plays a significant role in the nervous system by influencing the production of neurotransmitters like serotonin, dopamine, and GABA. Several studies have found low magnesium levels in individuals suffering from depression (Meta-analysis). Supplementation may alleviate symptoms (References). Stress and sleep deprivation can worsen depression risk, and magnesium can assist in managing stress levels.

Moreover, magnesium is essential for good sleep quality, and low levels can heighten sleep deprivation issues (Review). Additionally, magnesium may reduce the risk of migraines (Study).

Recommended Magnesium Intake and Best Food Sources

While ideal intake varies based on numerous factors, a minimum of 400-450 mg/day for men and 300-350 mg/day for women is recommended. Several studies observe additional benefits for individuals consuming more than 500 mg/day, particularly for brain health (Study).

Excellent Food Sources of Magnesium:

• Nuts, especially Brazil nuts, cashews, and almonds.
• Certain grains like oats.
• Legumes, particularly black beans.
• Leafy greens such as spinach and Swiss chard.
• Protein sources from fish like salmon provide decent magnesium content.
• Dark chocolate and cocoa (Video).
• Fruits, with bananas offering approximately 30 mg of magnesium.

Dosage and Types of Magnesium Supplements

While obtaining magnesium through food is optimal, due to increased processing methods, our diets often lack adequate magnesium . The recommended supplementation dose is within 250-450 mg/day, depending on dietary intake and individual needs.

In supplements, elemental magnesium is bound to other compounds, resulting in a variety of formulations. When selecting a magnesium supplement, consider the following:

• Bioavailability: This indicates the proportion of magnesium absorbed.
• Amount of Elemental Magnesium: This is more important than the total supplement dosage.
• Tolerance: Ensure it does not cause gastrointestinal discomfort.

Ideal options should possess high bioavailability, significant elemental magnesium content, and be well-tolerated.

Different formulations may target specific health concerns. If the goal is to increase magnesium levels, magnesium citrate is highly recommended due to its excellent bioavailability and tolerability. Magnesium carbonate is another viable option, being cost-effective and well-studied. On the other hand, magnesium oxide contains a high amount of elemental magnesium but has low bioavailability, so it is better suited for constipation relief. Similar considerations apply to magnesium chloride.

Magnesium glycinate, also known as bisglycinate, combines glycine and magnesium. This is an excellent option for improving sleep as glycine plays a role in collagen synthesis and enhances restfulness. Magnesium threonate is a newer formulation designed to cross the blood-brain barrier rapidly, which may help with disorders like migraines or anxiety, although more studies are required to confirm its efficacy.

Other forms such as magnesium malate, taurine, or magnesium sulfate tend to be more expensive with limited evidence supporting additional benefits.

Toxicity

Toxicity is rare from food sources because the kidneys will remove excess magnesium in the urine. However toxic levels may occur with long-term use of high-dosage supplements. People with kidney disease have a higher risk of toxicity because their kidneys are not working properly and cannot flush out extra magnesium. Signs of toxicity include: Nausea, vomiting Diarrhea Low mood, depression Muscle weakness Low blood pressure, abnormal heartbeat Heart attack 

My thouhgts

As a clinical nutritionist, I firmly believe in the pivotal role of magnesium in overall health. Ensuring adequate intake of this essential mineral is crucial for various bodily functions and mitigating associated health risks. Mindful dietary choices and, if necessary, supplementation can help achieve optimal magnesium levels.