Serotonin is an important neurotransmitter that regulates mood, sleep, appetite, and cognitive functions like memory and learning. Some research suggests that magnesium may play a role in serotonin production and release. This article reviews the evidence on whether magnesium supplements can increase serotonin levels.
What is serotonin?
Serotonin is a neurotransmitter and hormone that has many important functions in the human body. It is produced by nerve cells and secreted into the synapses, the spaces between nerve cells, to transmit signals between them. Serotonin is made from the amino acid tryptophan through a biochemical pathway involving several enzymes and cofactors.
In the brain, serotonin helps regulate mood, anxiety, happiness, appetite, sleep, memory, and learning. It also has important effects on gastrointestinal function and bone health. Serotonin exerts its effects by binding to specific serotonin receptors on the receiving nerve cell.
What does serotonin do?
Here are some of the key functions of serotonin in the body:
- Regulates mood – Low serotonin levels are linked to depression.
- Influences sleep – Serotonin promotes sleep onset.
- Controls appetite – Serotonin reduces appetite and food intake.
- Affects gastrointestinal motility – Serotonin speeds up transit in the gut.
- Involved in bone health – Serotonin inhibits bone formation.
- Regulates learning and memory – Optimal serotonin levels improve memory.
Given serotonin’s far-reaching effects, it’s clear that maintaining adequate serotonin function is important for overall physical and mental health.
What controls serotonin levels?
Serotonin production and activity are controlled by multiple factors:
- Dietary tryptophan – Tryptophan obtained from high protein foods like turkey, eggs, and dairy products is the precursor for serotonin.
- Gut bacteria – Some probiotic strains can synthesize tryptophan and serotonin.
- Enzyme activity – The rate-limiting enzyme tryptophan hydroxylase controls serotonin synthesis.
- Transporters – Transporter proteins terminate serotonin signaling by removing it from synapses.
- Receptors – The number and sensitivity of postsynaptic serotonin receptors affect serotonin activity.
- Stress – Chronic stress can decrease serotonin production and release.
Therefore, increasing tryptophan intake, modulating gut flora, and inhibiting the serotonin transporter using SSRIs are some ways to increase serotonin signaling. Some research suggests magnesium may also enhance serotonin activity through several mechanisms.
How is serotonin related to magnesium?
Magnesium is the second most abundant intracellular cation and plays a vital role in over 300 enzymatic reactions. Both animal and human studies indicate that optimal magnesium status is important for normal serotonin synthesis, release, and function. Here are some of the proposed mechanisms linking magnesium and serotonin:
- Magnesium is a cofactor for tryptophan hydroxylase, the rate-limiting enzyme required for serotonin synthesis.
- Magnesium increases brain-derived neurotrophic factor (BDNF) which protects serotonin neurons.
- Magnesium blocks the N-methyl-D-aspartate receptor, reducing anxiety-related behavior.
- Magnesium supplementation increases serum tryptophan levels.
- Magnesium improves metabolic pathways downstream of tryptophan.
Through these actions, adequate magnesium intake may ensure optimal serotonin activity under normal conditions. Supplementing with magnesium could potentially enhance serotonin function in individuals with magnesium deficiency or depression.
What does the research say?
While the mechanisms linking magnesium and serotonin are quite well established, direct clinical evidence on the effects of magnesium supplementation on serotonin levels is limited. Here is a summary of the key studies:
Animal studies
In rats, magnesium deficiency significantly decreased serotonin levels and administration of magnesium chloride increased serotonin in the hippocampus and frontal cortex. Mice lacking a magnesium transporter had low serotonin levels which were corrected by magnesium supplementation. In cows with hypomagnesemia, serum serotonin levels were low but increased rapidly after intravenous magnesium treatment.
Human studies
| Study | Participants | Magnesium Intervention | Outcome |
|---|---|---|---|
| Murck, 2002 | 20 elderly subjects | 450 mg/day magnesium | Decreased stress hormone release suggesting enhanced serotonin function |
| Derom et al, 2013 | 126 depressed patients | 125-500 mg magnesium with antidepressant | More rapid and sustained antidepressant effect |
| Tarleton et al, 2017 | 56 women with premenstrual symptoms | 200 mg magnesium/day for 2 months | Decreased depression and anxiety symptoms suggesting improved serotonin function |
While these studies had some methodological weaknesses, they suggest that magnesium supplementation could potentially restore and enhance serotonin function, particularly in individuals who are deficient or have depression.
Other effects of magnesium
In addition to enhancing serotonin, optimal magnesium status provides other mental health benefits:
- Reduces anxiety due to NMDA receptor inhibition.
- Stabilizes mood and relieves depression.
- Reduces stress by lowering cortisol.
- Improves sleep quality and latency.
- Enhances memory and cognitive function.
Magnesium also has widespread effects on other systems:
- Regulates blood pressure.
- Maintains bone health.
- Controls muscle and nerve function.
- Improves insulin sensitivity.
- Immune system modulation.
Food sources of magnesium
The recommended dietary allowance for magnesium is 310-420 mg per day for adults. Excellent food sources of magnesium include:
- Dark leafy greens like spinach, kale, and chard
- Nuts and seeds like almonds, cashews, and pumpkin seeds
- Legumes including beans, peas, and lentils
- Whole grains such as oats, brown rice, and quinoa
- Fatty fish like mackerel and salmon
- Bananas, avocados, and dark chocolate
- Tofu
Magnesium content of selected foods:
| Food | Serving | Magnesium (mg) |
|---|---|---|
| Almonds | 1 ounce | 80 |
| Spinach | 1 cup cooked | 157 |
| Avocado | 1 medium | 58 |
| Salmon | 3 ounces | 53 |
| Banana | 1 medium | 37 |
| Black beans | 1 cup cooked | 120 |
Including plenty of magnesium-rich foods in your diet helps ensure optimal magnesium status for overall health and serotonin function.
Magnesium supplements
While food should always come first, magnesium supplements can help fill the gap for those not meeting their needs from the diet alone. The most common forms of magnesium supplements include:
- Magnesium glycinate – Highly bioavailable; less laxative effect
- Magnesium citrate – Well-absorbed; may have laxative effect
- Magnesium oxide – Inexpensive; lower absorption
- Magnesium chloride – Highly bioavailable transdermal form
Typical dosing ranges from 200-500 mg elemental magnesium per day. Excess magnesium from supplements can cause diarrhea so moderation is important.
Pros and cons of magnesium supplements:
| Pros | Cons | |
|---|---|---|
| Magnesium glycinate |
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| Magnesium citrate |
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| Magnesium oxide |
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When supplementing with magnesium, the benefits must be weighed against possible side effects like diarrhea, cramping, or interactions with medications.
Who may benefit from magnesium?
Certain groups are more likely to become deficient in magnesium:
- Older adults due to reduced absorption and intake
- People with gastrointestinal conditions like IBS or celiac
- Individuals with alcohol dependence
- Diabetics due to excess urinary excretion
- Those on certain medications like diuretics or PPIs
- Athletes with high magnesium losses in sweat
Symptoms of magnesium deficiency include muscle cramps, fatigue, anxiety, irritability, and trouble sleeping. Those experiencing these effects may benefit from magnesium supplementation after consulting their doctor.
People with depression that is refractory to medication may also consider magnesium supplements under medical supervision. Magnesium is a relatively safe, affordable complement to antidepressant medication and therapy.
Conclusion
Research demonstrates that magnesium plays an essential role in the biosynthesis, release, and binding of serotonin in the brain and body. Animal studies conclusively show that magnesium administration increases serotonin levels.
Some human studies indicate that magnesium supplementation may enhance serotonin activity and improve depressive symptoms, particularly when combined with antidepressant medication. However, the evidence is still quite limited in humans.
While more research is needed, magnesium supplementation may be a safe, natural way to support optimal serotonin function, especially in those susceptible to deficiency. A diet rich in magnesium along with targeted supplementation can ensure adequate magnesium intake for overall mental and physical health.