Magnesium is involved in over 300 biochemical reactions in your body, yet it's estimated that up to 70% of Australians may not be getting enough of this essential mineral. The challenge? Magnesium deficiency often develops gradually, and its symptoms can easily be attributed to other causes—leading many people to unknowingly suffer from suboptimal levels.
In this article, we'll explore the ten most common signs that might indicate you're not getting enough magnesium, why deficiency is so widespread, and what you can do about it.
The symptoms listed here can have many causes beyond magnesium deficiency. This article is for educational purposes only. If you're experiencing persistent symptoms, consult your healthcare provider for proper diagnosis and treatment.
Why Is Magnesium Deficiency So Common?
Before exploring the symptoms, it helps to understand why so many people are affected:
- Depleted soils: Modern farming practices have reduced magnesium content in soil, meaning even healthy produce may contain less magnesium than it once did
- Food processing: Processing strips magnesium from foods—refined grains lose up to 85% of their magnesium
- Dietary choices: Diets high in processed foods and low in whole grains, nuts, seeds, and leafy greens provide inadequate magnesium
- Lifestyle factors: Stress, alcohol, caffeine, and intense exercise all increase magnesium depletion
- Medications: Some common medications, including certain diuretics and proton pump inhibitors, can affect magnesium levels
The 10 Signs of Magnesium Deficiency
1. Muscle Cramps and Spasms
Perhaps the most well-known sign of magnesium deficiency is muscle cramping. Magnesium is essential for proper muscle function—it helps muscles relax after contraction. Without adequate magnesium, muscles can contract involuntarily, causing painful cramps.
Common presentations:
- Nighttime leg cramps (particularly in the calves)
- Foot cramps
- Muscle twitches or spasms
- Charley horses during exercise
2. Sleep Difficulties
Magnesium plays a crucial role in sleep regulation. It helps activate the parasympathetic nervous system (the "rest and digest" system), regulates melatonin production, and binds to GABA receptors to calm the brain.
You might experience:
- Difficulty falling asleep
- Waking frequently during the night
- Restless, unrefreshing sleep
- Early morning waking
Poor sleep and magnesium deficiency can create a vicious cycle—lack of sleep increases stress, which depletes magnesium further, leading to even worse sleep. Breaking this cycle often requires addressing both issues.
3. Fatigue and Low Energy
Magnesium is required for ATP (energy) production at the cellular level. Every energy-consuming process in your body relies on magnesium-activated ATP. When magnesium is low, energy production becomes less efficient.
Signs to watch for:
- Persistent tiredness that sleep doesn't resolve
- Physical weakness or lack of stamina
- Feeling exhausted despite adequate rest
- Difficulty with physical activities that were once easy
4. Anxiety and Stress Sensitivity
Magnesium has a calming effect on the nervous system. It helps regulate the stress response and supports the production of calming neurotransmitters. Deficiency can lead to an overactive stress response.
Potential manifestations:
- Heightened anxiety or nervousness
- Feeling easily overwhelmed
- Difficulty relaxing or unwinding
- Exaggerated startle response
5. Headaches and Migraines
Research has shown connections between low magnesium levels and increased frequency of headaches, particularly migraines. Magnesium affects blood vessel function, neurotransmitter release, and pain signalling—all factors in headache development.
You might notice:
- Frequent tension headaches
- Increased migraine frequency or intensity
- Headaches triggered by stress or muscle tension
6. Irregular Heartbeat or Palpitations
Magnesium is vital for heart muscle function and maintaining normal heart rhythm. The heart is a muscle, and like all muscles, it requires magnesium to function properly. Deficiency can contribute to irregular heartbeats.
Warning: Heart-related symptoms should always be evaluated by a healthcare provider. While magnesium deficiency can cause palpitations, there are many other potential causes that need to be ruled out.
7. Constipation
Magnesium helps relax the smooth muscles of the intestines and draws water into the bowel, facilitating healthy elimination. Low magnesium can lead to sluggish bowel movements.
Related symptoms:
- Infrequent bowel movements
- Difficulty passing stools
- Hard, dry stools
This is why magnesium-based laxatives work—they draw water into the intestines and promote muscle relaxation. If you experience loose stools when starting oral magnesium, it may be too much too quickly. Topical magnesium doesn't have this effect.
8. Numbness and Tingling
Magnesium plays a role in nerve function. Deficiency can affect nerve signalling, potentially leading to abnormal sensations like numbness, tingling, or pins and needles—particularly in the extremities.
Note: Numbness and tingling have many potential causes. If you experience these symptoms, especially if persistent or severe, consult your healthcare provider.
9. Poor Concentration and Brain Fog
Magnesium is important for brain function and cognitive health. It supports neurotransmitter function and brain cell communication. Low levels can affect mental clarity and focus.
You might experience:
- Difficulty concentrating
- Mental fogginess
- Memory issues
- Decreased problem-solving ability
10. Increased Sugar Cravings
Here's a lesser-known sign: strong cravings for sugar or chocolate can sometimes indicate magnesium deficiency. Magnesium is involved in glucose metabolism, and when levels are low, the body may crave quick energy sources. Interestingly, dark chocolate is actually a good source of magnesium—perhaps explaining the craving connection.
Who's at Higher Risk?
Certain groups are more likely to be deficient in magnesium:
- Older adults: Absorption decreases with age, and dietary intake often declines
- Athletes: Increased losses through sweat and higher metabolic demands
- People with digestive conditions: Crohn's disease, celiac disease, and other GI issues can impair absorption
- Diabetics: High blood sugar increases magnesium excretion
- Heavy drinkers: Alcohol increases urinary magnesium loss
- Those under chronic stress: Stress hormones deplete magnesium stores
- People on certain medications: Including some diuretics, antibiotics, and proton pump inhibitors
Testing for Magnesium Deficiency
If you suspect you might be deficient, you might consider testing. However, there's a catch: standard blood tests measure only serum magnesium, which represents less than 1% of your total body magnesium. This test can appear normal even when tissue magnesium is low.
More accurate (but less commonly available) tests include:
- Red blood cell (RBC) magnesium
- Magnesium loading test
- Sublingual epithelial cell test
Many healthcare practitioners recommend assessing symptoms and dietary intake alongside any testing.
Addressing Magnesium Deficiency
If you recognise several of these symptoms in yourself, here are steps to consider:
Dietary Changes
Increase consumption of magnesium-rich foods:
- Dark leafy greens (spinach, Swiss chard, kale)
- Nuts and seeds (especially pumpkin seeds and almonds)
- Legumes (black beans, chickpeas, lentils)
- Whole grains (brown rice, quinoa, oats)
- Dark chocolate (70%+ cocoa)
- Avocado
Supplementation
Supplements can help bridge the gap between dietary intake and needs. Options include:
- Oral supplements: Various forms including citrate, glycinate, and oxide
- Topical magnesium: Sprays, oils, and creams applied to the skin
- Epsom salt baths: Magnesium sulphate absorbed through the skin
Lifestyle Modifications
- Manage stress (a major magnesium depleter)
- Moderate alcohol and caffeine consumption
- Ensure adequate sleep (magnesium and sleep are bidirectionally related)
For many people, a combination approach works best: improving dietary intake of magnesium-rich foods while supplementing with topical magnesium for targeted support. Start with our beginner's guide to learn the basics.
When to See a Healthcare Provider
Consult your doctor if:
- Your symptoms are severe or worsening
- You experience heart palpitations or chest pain
- You have numbness or tingling that persists
- You're on medications that might affect magnesium
- You have a medical condition that affects nutrient absorption
- You're considering high-dose supplementation
Conclusion
Magnesium deficiency is widespread but often overlooked. The symptoms—muscle cramps, poor sleep, fatigue, anxiety, headaches, and more—are commonly attributed to other causes or simply accepted as part of modern life. Yet for many people, optimising magnesium status can lead to meaningful improvements in how they feel.
If you recognise several of these signs in yourself, consider evaluating your magnesium intake. Whether through diet, supplementation, or both, ensuring adequate magnesium is a simple step that can have far-reaching effects on your health and wellbeing.
Ready to learn more? Explore the science of transdermal absorption or discover how to build a daily routine.