Magnesium: The Deficiency You Don’t Notice Until You Fix It

Most people assume they’re getting enough magnesium — especially if they eat “pretty well.” Even when you consume swiss-chard, spinach, almonds, pumpkin seeds, dark chocolate, and avocadoes on a regular basis, with this nutrient, the gap between what we think we’re getting and what our body actually needs is surprisingly wide. And that gap shows up in ways we often dismiss as normal: restless sleep, tight muscles, low resilience, cravings, irritability, or that wired‑but‑tired feeling at the end of the day.

A go‑to supplement in so many functional protocols, it sits at the centre of the systems we rely on most: energy production, stress regulation, blood sugar balance, hormone health, and deep, restorative sleep. When levels are low — and they often are — those systems have to work harder than they should.

Magnesium deficiency is incredibly common. Not because people are doing anything wrong, but because modern life makes it hard to maintain healthy levels. Our soils contain less magnesium than they used to, our diets are more processed, stress increases our demand, and certain medications reduce absorption. Put together, it’s easy to see why so many people feel noticeably better when they top up — assuming the right form, dose and time.

Same Mineral, Different Forms, Distinct Effects

Choosing the right form of magnesium is the difference between “nothing happened” and “why didn’t I take this before!”

Type	Best For	Why It Works	Side Effects / Notes
Glycinate	Sleep, anxiety, muscle tension, PMS, peri‑meno, stress	Highly absorbable; supports the nervous system; gentle on digestion	Minimal side effects; rarely causes digestive upset
Malate	Low energy, muscle soreness, daytime fatigue	Supports ATP production and muscle recovery	Generally well tolerated; good daytime option
Threonate (Mg‑L‑Threonate)	Focus, memory, cognitive support, midlife brain fog	Crosses the blood–brain barrier; supports cognitive function	No significant side effects; higher price point
Citrate	Constipation	Draws water into the bowel; effective for motility	Can cause loose stools; not ideal for systemic magnesium benefits
Oxide	Indigestion or constipation	Poor absorption; mostly acts in the gut	Digestive upset common; not recommended for raising magnesium levels

Tip: Magnesium bound to amino acids (glycinate, malate, threonate) absorb best. Taking magnesium with food improves tolerance and reduces the chance of digestive symptoms.

What to expect

With a good‑quality, well‑absorbed form, many people notice changes within 3–7 days:

·       deeper, more continuous sleep

·       calmer nervous system

·       fewer muscle twitches or cramps

·       steadier energy

·       improved bowel regularity (depending on the form)

·       reduced evening cravings

·       less “tired but wired” tension

Reliable, practitioner‑level brands tend to produce higher‑quality magnesium. Off‑the‑shelf options often use cheaper forms that don’t deliver the same effect.

Important considerations

Magnesium is generally safe for most healthy adults, but for anyone on multiple medications or with a chronic condition, personalised guidance is essential. If taking medication for kidney disease, heart or blood pressure issues, thyroid conditions, anxiety or sleep, you should always consult with your practitioner, as magnesium may be contraindicated or may need to be taken away from the medication. It can also reduce the absorption of certain antibiotics. As with most supplements, it’s always better to check than to self‑prescribe.

Magnesium isn’t glamorous, but it’s one of the most impactful, evidence‑backed supplements you can add to your routine — especially in a world that constantly drains it. And while it’s widely beneficial, it’s not one‑size‑fits‑all. The right form, dose and timing depend on your physiology, your stress load, your sleep, your hormones and your medications.

If you’re unsure which type is right for you, seeking professional advice is always worth it. A small adjustment can make a meaningful difference.