Magnesium for 😴Sleep: Types, Foods, Studies

• Magnesium is crucial for health, and sleep in particular.
• More than 50% of people have a Magnesium deficiency.
• 12 clinical studies have shown the efficiency of Magnesium for sleep improvement and reducing anxiety.
• Best Food sources include seeds (pumpkin, hemp, flax, chia), bran, cocoa, nuts.
• Magnesium Glycinate (14% Mg, 86% Glycine) is probably the best magnesium type for sleep because it is organic and has high bioavailability; and Glycine alone was also shown to be efficient in sleep improvement in 3 clinical studies, which makes it a perfect combo with magnesium.

 

There are on average 25 g of Magnesium in a human body (0.4 g/kg of weight). It is crucial for the work of around 300 enzymes in 600 biochemical reactions across all body systems. [1]

Magnesium regulates energy production, muscle contraction, nerve impulse transmission, protein synthesis, blood sugar control, heart contraction, blood pressure, and other crucial processes. [2]

 

Content:

• Magnesium in Human Physiology & Health
• Magnesium and Sleep
• Magnesium Daily Intake
• Magnesium Deficiency
• Magnesium Supplements
• Magnesium in Foods
• Human Studies

 

 

Magnesium in Human Physiology & Health

The five domains of intrinsic capacity and the subdomains in which magnesium plays a significant role (adapted from Souza, A. C. R., et al., 2023)

Magnesium is a vital mineral that plays a central role in maintaining human health by acting as an essential cofactor in over 600 enzymatic reactions. [1,2]

• At the cellular level, magnesium is indispensable for energy production through its involvement in ATP synthesis (the main energy molecule), where it stabilizes and activates ATP molecules—biochemical processes fundamental to life. [3,4]
• Magnesium regulates ion channels and modulates the flow of calcium and potassium ions, which are crucial for nerve impulse transmission [5,6], muscle contraction [7,8], and heart rhythm maintenance [9,10]. This helps maintain a calm resting state in neurons and muscles.
• Magnesium is also key to protein synthesis [11] and nucleic acid stability [12,13]. It assists in ribosomal function, ensuring efficient translation of genetic information into proteins, and supports the integrity of DNA and RNA by stabilizing their phosphate backbones. This is critical for preventing oxidative stress and maintaining genomic stability.
• Furthermore, magnesium regulates vascular tone by influencing endothelial function and smooth muscle relaxation [14]. This effect may play a preventive role in cardiovascular diseases like hypertension [15,16].

In summary, magnesium’s multifaceted roles illustrate its indispensability in human physiology. This broad spectrum of functions also sets the stage for understanding its potential influence on sleep regulation and overall neurological function.

 

Magnesium roles in physiological processes (adapted from Fritzen, R. et al., 2023)

 

 

Magnesium and Sleep

The Neurochemistry of Magnesium in Stress & Sleep (adapted from Pickering, G. et al., 2020)

 

In terms of sleep, Magnesium plays its role through numerous "calming" mechanisms:

• Magnesium opposes the excitatory action of calcium, for example, in the process of muscle relaxation or brain "relaxation" through NMDA receptors [1,5,18];
• Magnesium stimulates GABA receptors to reduce the excitability of the nervous system [19,20];
• Magnesium plays a role in melatonin synthesis from 5-HT (5-hydroxytryptamine) in the brain [21];
• Magnesium indirectly reduces the release of ACTH (adrenocorticotropic hormone), which decreases cortisol levels (a stress hormone), resulting in calming the central nervous system and potentially better sleep [22,23].

 

Magnesium Status and Stress (adapted from Pickering, G. et al., 2020)

 

 

Magnesium Daily Intake

The Recommended Daily Allowance (RDA) is 5–7 mg/kg/day [24,25]:

• about 400-420 mg for men,
• and 310-320 mg for women.

Some people may require more daily Magnesium intake than 320-420 mg RDA [1,25]:

• Athletes are recommended to consume higher amounts of magnesium. Magnesium activates protein synthesis, ATP production (main energy molecule), and mitochondrial health, and supports bone health. With exercise, magnesium levels decrease; therefore, athletes require more magnesium daily.
• Pregnant women.
• Older people absorb less magnesium from the gut and lose more magnesium because of an increased renal excretion and estrogen deficit.
• People affected by type 2 diabetes and gastrointestinal diseases, such as Crohn’s disease, inflammatory bowel diseases, and celiac disease.
• Several drugs can cause magnesium loss and deficiency, including:
  • Diuretics (HCT, furosemide);
  • Proton-pump inhibitors (omeprazole, pantoprazole, etc.);
  • Anti-diabetic medication (insulin, insulin mimetic drugs);
  • Beta adrenergic agonists (fenoterol, salbutamol, theophylline);
  • Aminoglycoside antibiotics (gentamicin, tobramycin, amikacin, etc.);
  • and some others [26].

 

 

Magnesium deficiency

Over 50% of the population may have magnesium deficiencies, consuming less than the Recommended Daily Allowance (RDA) of 320 to 420 mg/day (5–7 mg/kg/day). [24,25]

A 2022 study of 766 adolescents 14-18 years old in the southeast US has concluded that "The average daily magnesium intakes were ~200 mg and ~205 mg for males and females, respectively, far below the recommended amounts of 410 mg for males and 360 mg for females... Almost none of the adolescents met the recommendations." [27]

Symptoms of magnesium deficiency may include muscle weakness, seizures, headaches, nausea, and depression, among others. [28]

Magnesium deficiency is associated with cardiovascular disease, high blood pressure, type 2 diabetes, depression, Alzheimer’s disease, age-related muscle loss, and others. [25]

 

 

Magnesium supplements

Various forms of Magnesium supplements are available commercially, including inorganic magnesium, organic magnesium, and their combinations. [24,29]

• Inorganic salts provide a high loading of elemental magnesium but exhibit a limited bioavailability. They include (with the content of elemental Mg in mg/100mg): oxide (60), chloride (12).
• Organic salts of magnesium offer high bioavailability but provide less elemental magnesium. They include (with the content of elemental Mg in mg/100mg): glycinate (10-14), threonate (8), taurate (9), malate (15), lactate (12), aspartate hydrochloride (10), citrate (16), orotate (6), glycerophosphate (11).
• Magnesium glycinate consists of 14% elemental Magnesium and 86% amino acid Glycine, which by itself also helps improve sleep and is beneficial for many other health outcomes. For example, 3 clinical studies have shown that Glycine improved sleep quality, alertness and cognition, and decreased fatigue and sleepiness in dosages of 3 g/day before bedtime. [30,31,32]
  Moreover, glycine positively affects metabolic health by improving insulin responses, decreases systolic blood pressure in the cardiovascular system, reduces proinflammatory cytokines in the immune system, and is studied on preventing, delaying or reversing the ageing. [33]
  

 

 

Magnesium in foods

In general, seeds (pumpkin, hemp), nuts, whole grains, legumes, some fruits, and cocoa are good sources of magnesium. [1]

Food Product	Magnesium content (mg/100g)
Pumpkin and squash seed, dried	430-600
Wheat/Cereal bran	450-550
Cocoa powder	500-550
Hemp seeds	350-400
Flaxseed	390
Chia seeds	330-390
Wheat germ	250-270
Cashews dried	260
Almonds, dried	250-260
Peanuts, roasted	175-230
Buckwheat flour, whole-groats	120-240
Quinoa	190
Hazelnuts, dried	160
Pecans	120-160
Beans, dried	160-170
Walnuts, dried	150-160
Pistachios, dried	150-160
Chickpeas, dried	130-160
Millet, shelled	115-160
Wheat flour, hard	120-140
Seaweed, kelp, raw	120
Macadamia	115-120
Whole-wheat pasta	100-110
Lentils, dried	80-110
Avocado	29
Banana	27
Papaya	21

• Cooking (especially boiling) and the refining processes may consistently diminish the Mg content present in the food. [25]
• Glyphosate, a pesticide frequently used in crops, may reduce the content of Mg in soil and in some crops. Organic pesticide-free food has significantly higher Mg content than non-organic food. [25]
• Coffee and alcohol may decrease Mg bioavailability [1]
• High calcium and phosphorus intake may also decrease Mg bioavailability [1]
• Mg consumption from water rich in Mg may be a good source of Mg. [34]
  The bio-availability of Mg in drinking water is generally high, approximately 50%, when consumed alone, and even higher when consumed with food. [35]
  Cooking in water high in Mg may reduce the loss of Mg in the boiled food. [25]
• Unrefined sea salt is rich in magnesium, approximately 400-500 mg/100 g. [1]

 

 

Human studies

A 2024 systematic review, published in Cureus, has summarized 15 studies, including randomized controlled clinical trials (11) and observational studies (4), that studied the efficiency of Magnesium (in dosage over 100 mg) for sleep improvement (8) and coping anxiety (7). [36]

 

Sleep studies

Overall,

• 5/8 studies reported positive results of Magnesium intake on sleep parameters.✅
• 2 studies reported no efficiency❌, but
• in one study, the dosage was extremely low: ~12 mg of elemental Magnesium;
• in another study, Mg was taken with the breakfast, which is too early
• 1 featured mixed results. [36]

The primary sleep metric used by the majority of studies was the Pittsburgh Sleep Quality Index (PSQI), a self-reported questionnaire. The majority (5/8) of the studies used inorganic Magnesium Oxide (MgO). [36]

Anxiety studies

7 of the 15 studies included in the systematic review mentioned earlier studied the effects of magnesium supplementation on measures of anxiety. [36]

• ✅ 5/7 studies reported positive results. Importantly, several of these studies included magnesium combined with vitamin B6; and 1 study combined with 2 medical plants. The two trials with the greatest reductions in anxiety scores used relatively high doses of magnesium (300 mg elemental magnesium each) combined with vitamin B6.
• ❌ The one study with no results used 320 mg of magnesium sulfate that contained only 64.6 mg of elemental magnesium – the lowest amount of magnesium used in any of the 15 studies included in that review. Another study reported decreased self-reported anxiety scores only when magnesium was combined with 50 mg of vitamin B6. However, urinary excretion of magnesium during this trial didn't change, leading the authors to question the absorption of the magnesium oxide in that study.

To measure the results, different scores were used — the Hamilton Anxiety Rating Scale (HAM-A) was used in two of the studies; other anxiety outcome measures used included the Revised Child Anxiety and Depression Scale (RCADS), the Spielberger State-Trait Anxiety Inventory (STAI), the Depression Anxiety Stress Scales (DASS), and the Hospital Anxiety and Depression Scale (HADS). [36]

De Souza et al. (2000)

• Participants: 44 (crossover trial; each served as own control)
• Dosage & Form: 200 mg MgO; 200 mg MgO + 50 mg vitamin B6; 50 mg vitamin B6; placebo.
• Results: Significantly lower anxiety scores during treatment with the combination of magnesium and vitamin B6, but not with just magnesium; and urinary magnesium did not differ significantly between groups.❌

Hanus et al. (2003)

• Participants: 264 (134 control, 130 treatment)
• Dosage & Form: 248.7 mg MgO (150 mg elemental magnesium) plus two plant extracts (Crataegus oxyacantha and Eschscholtzia californica), daily for 90 days.
• Results: Total HAM-A score decreased significantly more in the treatment group versus placebo (-10.6 versus -8.9); VAS subjective anxiety score decreased significantly more in treatment group versus placebo (-38.5 versus -29.2); significantly greater response rate in treatment group versus placebo for both the HAM-A and the VAS scores.✅

Fard et al. (2017)

• Participants: 99 (33 control, 33 zinc, 33 magnesium)
• Dosage & Form: 320 mg of magnesium sulfate (MgSO4) (64.6 g of elemental magnesium) daily for 8 weeks.
• Results: No significant differences were found in depression and anxiety scores between the placebo, zinc, and magnesium groups.❌

Kovacevic et al. (2017)

• Participants: 32
• Dosage & Form: MgO or magnesium glycinate, 4-6 mg/kg/day for six months
• Results: Self-reported anxiety scores decreased significantly between baseline and six months; scores between baseline and three months trended lower but did not achieve significance.✅

Noah et al. (2020)

• Participants: 264 (132 control, 132 treatment)
• Dosage & Form: 300 mg magnesium lactate dihydrate total (across six tablets) daily for eight weeks
• Results: DASS anxiety subscale scores decreased significantly from baseline in both the magnesium and magnesium+B6 groups.✅

Saba et al. (2022)

• Participants: 60 (30 control, 30 treatment)
• Dosage & Form: 500 mg MgO daily for five days
• Results: The mean HADS score was significantly lower in the treatment group versus the control group.✅

Oddoux et al. (2022)

• Participants: 93
• Dosage & Form: 300 mg magnesium (270 mg as MgO and 30 mg as magnesium bisglycinate), 200 mg fish protein hydrolysate, and 1.4 mg B6 daily for four weeks
• Results: 41.9% experienced a ≥50% decrease in HAM-A score; mean HAM-A score decreased by 12.1 points; 75.3% improved significantly or very significantly on CGI scale.✅

 

 

Conclusion

• Magnesium is crucial for health, and sleep in particular.
• More than 50% of people have a Magnesium deficiency.
• 12 clinical studies have shown the efficiency of Magnesium for sleep improvement and reducing anxiety.
• Best Food sources of Magnesium: seeds (pumpkin, hemp, flax, chia), bran, cocoa, nuts.
• Magnesium glycinate (14% Mg, 86% Glycine) is probably the best magnesium type for sleep because it is organic and has high bioavailability; and Glycine alone was also shown to be efficient in sleep improvement in 3 human studies, which makes it a perfect combo for sleep.