Are we all deficient in magnesium?

Why magnesium matters

Magnesium is required for over 300 biochemical reactions in the body, although some estimates suggest magnesium could be the unsung hero in as many as 600 bodily functions. Without it, enzymes cannot work properly, creating kinks in the way our body operates, and those kinks manifest as fatigue, poor sleep, low mood, and more. That is because magnesium influences so much…

• Energy production – it activates adenosine triphosphate (ATP), the body’s primary energy molecule. No magnesium, no usable energy.
• Muscle contraction and relaxation – it regulates the flow of calcium into muscle cells, preventing cramping and promoting proper function.
• Nervous system health – it modulates neurotransmitters that regulate mood, including serotonin and melatonin.
• Blood pressure control – magnesium helps relax blood vessels, supporting healthy circulation and heart rhythm.
• Bone formation – around 60% of the body’s magnesium is stored in the bones, contributing to bone density alongside calcium, Vitamin K2 and Vitamin D.
• Glucose metabolism – magnesium plays a role in how the body handles insulin and blood sugar levels.

So, yes, it’s pretty clear that without enough magnesium, these bodily functions and systems become less efficient. 

You might notice muscle spasms, low energy, irregular heartbeats, poor sleep, or feeling more stressed than usual. However, because magnesium supports numerous processes simultaneously, deficiency symptoms can be subtle, broad, and easily misattributed to other causes.

Are we getting enough? The hidden epidemic of low magnesium

Here’s the tricky part, magnesium deficiency is rarely evident on blood tests. Only about 1% of the body’s magnesium is found in the bloodstream, so normal blood levels don’t necessarily mean you’re getting enough where it’s needed most – inside your cells.

Note: Although many private blood panels now offer magnesium testing, largely because of its rise in popularity as a supplement, this isn’t something I generally recommend, for the reasons I’ve outlined above.

In reality, low magnesium status is a widespread issue. Up to two-thirds of adults in developed countries may not meet the recommended daily intake of 300-400mg (click here for all age recommendations). 

Populations at higher risk include older adults, people with type 2 diabetes, those with gastrointestinal issues like Crohn’s disease, and individuals taking certain medications, such as diuretics (common for blood pressure) or PPI’s like Omeprazole and Lansoprazole.

Common signs that magnesium may be low include:

• Persistent fatigue or muscle weakness
• Cramping or twitching muscles
• Sleep disturbances or restless legs
• Anxiety, irritability, or frequent mood swings
• High blood pressure or heart palpitations

Individually, these symptoms might not raise alarm bells — but together, they often point toward the missing mineral.

But… magnesium should be abundant in foods, so why are we all lacking in this vital nutrient?

Are depleted soils the source of the problem?

There was a time when it was relatively easy to meet magnesium needs through a basic, whole-food diet; however, modern agricultural practices have altered the story.

Over the past century, intensive farming has leached magnesium, along with other vital minerals, from the soil. Fertilisers are designed to maximise crop yields, but they rarely replace soil nutrients such as magnesium. As a result, foods grown today, even organic ones, typically contain less magnesium than their historical counterparts.

(Check out our blog on organic food)

Combine this with food processing and the depletion continues. When grains are refined into white flour, there is potential for around 80-90% of their magnesium to be lost. When foods are canned, frozen, and processed into new food products, they are often stripped of minerals during those processes, leaving behind calories with reduced nutritional value. This is where fortification is frequently introduced.

Even for those trying to eat healthily, it can be surprisingly challenging to reach optimal magnesium intake unless you consciously include good levels of magnesium-rich foods in your daily diet.

Foods rich in magnesium include:

• Leafy greens (spinach, Swiss chard, kale)
• Nuts and seeds (almonds, cashews, pumpkin seeds, chia)
• Legumes (black beans, chickpeas, lentils)
• Whole grains (brown rice, oats, quinoa, buckwheat)
• Dark chocolate (minimum 70% cocoa)
• Avocados, bananas, and tofu

But food is not the end of the story

Soil and food play a significant role, but, as with most health issues, low magnesium levels are multifactorial. To really improve our health, we need to approach it holistically and consider all factors, including;

• Stress – chronic stress increases magnesium excretion through the urine. In stressful times, we burn through magnesium more rapidly, just when we need it most.
• Dietary changes – highly processed foods dominate the modern diet, yet they are stripped of natural magnesium during processing.
• Caffeine and alcohol – both increase urinary magnesium losses.
• Medications – as previously mentioned, some medications prevent absorption (PPIs), while others increase excretion (diuretics).

With this knowledge, what can you change to help increase your magnesium levels?  Magnesium levels don’t change overnight, but many people start to feel better – more relaxed, experience better sleep, and have fewer cramps – within a few weeks of making targeted changes.

Supplements are available and may support improvements alongside other lifestyle changes. However, remember that supplements don’t replace the importance of diet and lifestyle choices. Focusing on a 360-degree approach to health is what leads to long-lasting results.