I have been taking magnesium supplements for a while now, as I discovered I was very low and it was affecting my body. I was struggling to sleep, ached all the time for no reason, and kept getting really bad cramps.
At first, I put it down to stress, getting older, and not drinking enough water. But as the symptoms persisted, I started to get worried and went to the doctor, who told me I was very low in magnesium.
It was a relief to know it wasn’t anything serious and something I could easily fix by taking a supplement. I’m now sleeping properly at night, and the aches are nowhere near as bad. But there are more telltale signs than the ones I had. The warning signs are easy to miss or misattribute to something else entirely.
9 Warning Signs Your Body May Be Critically Low In Magnesium
Around half of all Americans don’t get enough magnesium, yet it rarely shows up on a standard blood test. That’s a problem, because magnesium is involved in over 300 biochemical processes in your body. When levels drop, the effects show up everywhere.
Muscle Twitches & Cramps
Magnesium and calcium work together to control muscle contractions. Calcium triggers a contraction, and magnesium signals the muscle to release and relax. When magnesium runs low, calcium keeps firing, and muscles struggle to let go. The result is twitching, spasming, and those sudden leg cramps that jolt you awake in the middle of the night.
It usually starts small with a fluttering eyelid or a twitch in the calf. But left unchecked, it can escalate to more persistent cramps and muscle stiffness that don’t ease up.
Chronic Fatigue & Weakness
If you’re sleeping eight hours and still dragging yourself through the day, the problem may not be your sleep at all.
Your cells need magnesium to produce ATP, which is your body’s primary energy currency. Every single cell in your body runs on it. Without enough magnesium, that energy production slows down. Rest doesn’t fix it because the problem isn’t how long you’re sleeping, but that your body can’t generate fuel efficiently.
The fatigue that comes with low magnesium makes your limbs feel heavy, and even the simplest tasks feel like hard work. It’s that feeling that you’re running on empty, no matter what you do.
Insomnia & Sleep Disorders
There’s nothing worse than lying in bed at night, wide awake with your mind still racing at 2 am.
Magnesium activates your parasympathetic nervous system, which is the part responsible for rest and recovery. It helps bring cortisol down in the evenings and supports melatonin production, the hormone that signals to your brain that it’s time to sleep.
When magnesium levels are low, your stress response stays on longer than it should. Cortisol stays elevated, and the melatonin struggles to kick in, and your sleep becomes fragmented and shallow.
If you find yourself waking up multiple times in the night, or lying awake for long stretches, it’s worth considering whether a lack of magnesium is the root of the problem.
Migraines & Headaches
Migraines are debilitating, and if you suffer from them regularly, low magnesium may be a significant factor.
Magnesium plays a key role in regulating blood flow in the brain. When levels drop, it can trigger something called cortical spreading depression, an abnormal wave of electrical activity that causes blood vessels to constrict suddenly. That constriction is closely linked to migraine onset.
Research has consistently found that people who suffer from migraines tend to have lower magnesium levels than those who don’t. Many migraine sufferers report a noticeable reduction in frequency once their magnesium levels are restored.
Osteoporosis & Bone Density Loss
Most people associate bone loss with calcium deficiency, but magnesium is just as critical to keeping your bones strong.
About 60% of the magnesium in your body is stored in your bones. It helps your body absorb calcium properly and activates vitamin D, which is the nutrient responsible for getting calcium into bone tissue in the first place. Without enough magnesium, calcium can’t do its job, no matter how much dairy you eat or how many supplements you take.
Low magnesium levels over time contribute to reduced bone density. You often don’t know it’s happening until a scan reveals the damage, or worse, until a minor fall causes a fracture.
Numbness & Tingling
That pins-and-needles feeling in your hands and feet that comes and goes without explanation could be more than just an awkward sleeping position.
Magnesium regulates the electrical activity of your nerve cells. When levels drop, nerve cells become overexcitable and start firing signals in disorganized patterns. That shows up as tingling, numbness, or the sensation that your limbs are constantly falling asleep.
It typically starts in the hands and feet, then spreads further up the limbs. Some people describe it as a crawling feeling under the skin. Others feel intermittent electric shocks running through their fingers or toes.
Because these symptoms can mimic several neurological conditions, they are often investigated in depth before anyone considers checking magnesium levels.
Digestive Problems
Your digestive tract is essentially one long muscle. It moves food through your system via rhythmic contractions called peristalsis, and those contractions depend heavily on magnesium.
When levels fall, the gut slows down, and food sits in the stomach longer than it should. Bowel movements become infrequent and uncomfortable. Bloating and nausea start to feel like your new normal.
Chronic constipation that doesn’t respond well to dietary changes is a common complaint among people with low magnesium. In more severe cases, nausea and vomiting can develop as deficiency deepens. Your entire digestive system, from stomach to colon, relies on this mineral to keep things moving.
Increased Inflammation
Inflammation is your body’s natural response to injury or infection. And low magnesium creates the conditions for it to become chronic.
When magnesium levels drop, inflammatory markers like C-reactive protein and cytokines rise. Your immune system loses some of its ability to regulate itself, resulting in a slow-burning internal fire that contributes to conditions like heart disease and autoimmune disorders.
A 2024 review linked magnesium deficiency to systemic inflammation and identified it as a key driver of atherosclerosis.Â
Loss of Appetite
This one tends to appear later, as deficiency deepens, but it’s worth knowing about because it can set off a cycle that’s hard to break.
Magnesium is involved in the metabolic processes that regulate hunger signals. When levels fall low enough, the system starts to malfunction. Food loses its appeal, and it becomes easy to forget to eat. A few bites in, and you feel full, and your stomach feels unsettled even when it’s empty.
The danger here is that poor appetite leads to poor nutrition, which worsens the deficiency. It becomes self-reinforcing. This pattern is particularly common in older adults and in people recovering from illness, where it can seriously slow down recovery.
If your appetite has dropped off without an obvious reason, it’s worth mentioning to your doctor and asking to have your magnesium levels checked.
How To Boost Your Magnesium Levels
The good news is that low magnesium is one of the easier deficiencies to address. You have two straightforward routes: food and supplements. Most people find a combination of both works best.
Food First
Some of the best dietary sources of magnesium are foods you probably already eat. Dark leafy greens like spinach and kale are among the richest sources. A cup of cooked spinach delivers around 157mg. Pumpkin seeds are another powerhouse, with a one-ounce serving providing close to 150mg.
Other solid sources include:
- Dark chocolate (70% cocoa or higher)
- Almonds and cashews
- Black beans and lentils
- Avocado
- Whole grains like brown rice and quinoa
- Bananas
- Salmon and mackerel
The challenge is that modern farming practices have depleted soil magnesium levels, so even a healthy diet doesn’t always guarantee adequate intake. That’s where supplements come in.
Supplements
Not all magnesium supplements are created equal, and this is where a lot of people go wrong. The type of magnesium matters.
Magnesium glycinate is widely considered the best option for most people. It’s well absorbed, gentle on the stomach, and particularly good for sleep and anxiety. This is the form most commonly recommended for people who are deficient.
Magnesium citrate is another well-absorbed form and works well for people who also struggle with constipation, as it has a mild laxative effect.
Magnesium oxide is the cheapest and most widely available form, but it has poor absorption rates. It’s the one you’ll most often find in budget supplements, and it’s worth paying a little more to avoid it.
The recommended daily allowance for magnesium is 320mg for women over 31 and 420mg for men over 31. If you’re considering a supplement, starting with 200 to 400mg daily is a reasonable starting point, but always check with your doctor first, especially if you take any medication, as magnesium can interact with certain drugs, including antibiotics and blood pressure medication.
One more thing worth knowing: magnesium is also absorbed through the skin. Magnesium flakes dissolved in a warm bath or a topical magnesium spray are popular options for people who find oral supplements cause digestive discomfort.
Disclaimer: The health and wellness content in this article is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult your healthcare provider before making changes to your diet, supplement routine, or lifestyle, particularly if you have an existing health condition or are taking medication.