The Most Common Deficiency
Magnesium is a cofactor in over 300 enzymatic reactions in your body, regulating everything from sleep to muscle recovery. It is estimated that nearly 50% of the US population is deficient. Naturally, people turn to supplements.
But walk into a pharmacy, and you are likely to buy the wrong one.
The Villain: Magnesium Oxide
The most common form on the shelf is Magnesium Oxide. It is popular with manufacturers because it is cheap and has a high "elemental weight" (meaning they can fit a lot of magnesium atoms into a small pill).
The Problem: Your body can't absorb it. A study in Magnesium Research found that the fractional absorption of Magnesium Oxide is notoriously low—often cited around 4%.
The Consequence: If you take a 500mg pill and absorb only 20mg, the remaining 480mg stays in your gastrointestinal tract. Magnesium is osmotic—it draws water from your surrounding tissues into your colon. This flushes everything out. Essentially, Magnesium Oxide is an expensive laxative, not a nutritional supplement.
The Hero: Chelated Magnesium
To fix absorption, scientists bind magnesium to organic molecules (amino acids) that your body actively transports across the gut lining. This is called "chelation."
1. Magnesium Glycinate (For Sleep)
Here, magnesium is bound to Glycine, an inhibitory neurotransmitter that promotes relaxation.
- Absorption: Very high.
- Side Effects: Virtually zero digestive upset.
- Best For: Insomnia, anxiety, and general deficiency.
2. Magnesium L-Threonate (For Brain)
Most magnesium forms struggle to cross the Blood-Brain Barrier. Researchers at MIT developed Magnesium L-Threonate specifically to solve this.
- The Science: Animal studies show it significantly elevates magnesium levels in the cerebrospinal fluid, improving synaptic density and memory.
- Best For: Cognitive decline, "brain fog," and memory.
The WellFact Protocol
Check your label immediately.
- If it says: Magnesium Oxide, Citrate (unless constipated), or Carbonate... Swap it.
- Buy: Magnesium Glycinate or Bisglycinate.
- Dose: 200-400mg before bed.