Magnesium is a mineral found in the earth, sea, plants, animals and humans.
About 60% of the magnesium in your body is found in bone, while the rest is in muscles, soft tissues and fluids, including blood (1).
In fact, every cell in your body contains it and needs it to function.
One of magnesium’s main roles is acting as a cofactor or helper molecule in the biochemical reactions continuously performed by enzymes.
In fact, it’s involved in more than 600 reactions in your body, including (2):
- Energy creation: Helps convert food into energy.
- Protein formation: Helps create new proteins from amino acids.
- Gene maintenance: Helps create and repair DNA and RNA.
- Muscle movements: Is part of the contraction and relaxation of muscles.
- Nervous system regulation: Helps regulate neurotransmitters, which send messages throughout your brain and nervous system.
2. It May Boost Exercise Performance
Magnesium also plays a role in exercise performance.
During exercise, you may need 10–20% more magnesium than when you’re resting, depending on the activity (4).
Magnesium helps move blood sugar into your muscles and dispose of lactate, which can build up during exercise and cause fatigue (5).
In one study, volleyball players who took 250 mg of magnesium per day experienced improvements in jumping and arm movements (9).
In another study, athletes who supplemented with magnesium for four weeks had faster running, cycling and swimming times during a triathlon. They also experienced reductions in insulin and stress hormone levels (10).
3. Magnesium Fights Depression
One analysis in over 8,800 people found that people under the age of 65 with the lowest magnesium intake had a 22% greater risk of depression (14).
Some experts believe the low magnesium content of modern food may cause many cases of depression and mental illness (15).
However, others emphasize the need for more research in this area (16).
In a randomized controlled trial in depressed older adults, 450 mg of magnesium daily improved mood as effectively as an antidepressant drug (17).
4. It Has Benefits Against Type 2 Diabetes
Magnesium also benefits people with type 2 diabetes.
One study which followed more than 4,000 people for 20 years found that those with the highest magnesium intake were 47% less likely to develop diabetes (21).
Another study showed that people with type 2 diabetes taking high doses of magnesium each day experienced significant improvements in blood sugar and hemoglobin A1c levels, compared to a control group (22).
However, these effects may depend on how much magnesium you’re getting from food. In a different study, supplements did not improve blood sugar or insulin levels in people who weren’t deficient (23).
5. Magnesium Can Lower Blood Pressure
In one study, people who took 450 mg per day experienced a significant decrease in systolic and diastolic blood pressure (27).
However, these benefits may only occur in people who have high blood pressure.
Another study found that magnesium lowered blood pressure in people with high blood pressure but had no effect on those with normal levels (28).
6. It Has Anti-Inflammatory Benefits
In one study, children with the lowest blood magnesium levels were found to have the highest levels of the inflammatory marker CRP.
They also had higher blood sugar, insulin and trygliceride levels (32).
In the same way, high-magnesium foods — such as fatty fish and dark chocolate — can reduce inflammation.
7. Magnesium Can Help Prevent Migraines
Migraine headaches are painful and debilitating. Nausea, vomiting and sensitivity to light and noise often occur.
Some researchers believe that people who suffer from migraines are more likely than others to be magnesium deficient (36.
In one study, supplementing with 1 gram of magnesium provided relief from an acute migraine attack more quickly and effectively than a common medication (39).
Additionally, magnesium-rich foods may help reduce migraine symptoms (40).
8. It Reduces Insulin Resistance
Insulin resistance is one of the leading causes of metabolic syndrome and type 2 diabetes.
It’s characterized by an impaired ability of muscle and liver cells to properly absorb sugar from your bloodstream.
Magnesium plays a crucial role in this process, and many people with metabolic syndrome are deficient (3).
In addition, the high levels of insulin that accompany insulin resistance lead to the loss of magnesium through urine, further reducing your body’s levels (41).
One study found that supplementing with this mineral reduced insulin resistance and blood sugar levels, even in people with normal blood levels (45).
9. Magnesium Improves PMS Symptoms
Premenstrual syndrome (PMS) is one of the most common disorders among women of childbearing age.
Its symptoms include water retention, abdominal cramps, tiredness and irritability.
Magnesium is absolutely essential for good health. The recommended daily intake is 400–420 mg per day for men and 310–320 mg per day for women (48).
You can get it from both food and supplements.
The following foods are good to excellent sources of magnesium (49):
- Pumpkin seeds: 46% of the RDI in a quarter cup (16 grams)
- Spinach, boiled: 39% of the RDI in a cup (180 grams)
- Swiss chard, boiled: 38% of the RDI in a cup (175 grams)
- Dark chocolate (70–85% cocoa): 33% of the RDI in 3.5 ounces (100 grams)
- Black beans: 30% of the RDI in a cup (172 grams)
- Quinoa, cooked: 33% of the RDI the in a cup (185 grams)
- Halibut: 27% of the RDI in 3.5 ounces (100 grams)
- Almonds: 25% of the RDI in a quarter cup (24 grams)
- Cashews: 25% of the RDI in a quarter cup (30 grams)
- Mackerel: 19% of the RDI in 3.5 ounces (100 grams)
- Avocado: 15% of the RDI in one medium avocado (200 grams)
- Salmon: 9% of the RDI in 3.5 ounces (100 grams)
If you are taking certain diuretics, heart medications or antibiotics, check with your doctor before taking magnesium supplements.
Supplementary forms that are well absorbed include magnesium citrate, glycinate, orotate, and carbonate, while oxidized ones have slightly poorer absorption.
Remember, if you do not have enough of this important mineral, your body cannot function optimally.