I know I need magnesium on keto. But there are about 15 different forms at the supplement store — oxide, citrate, glycinate, malate, threonate, taurate. How do I know which one to buy? They all seem to claim different benefits.
The forms differ primarily in bioavailability (how much gets absorbed) and secondary effects. Here's the practical breakdown:
Magnesium glycinate — best for sleep, anxiety, and muscle relaxation. Very high absorption (~80%). No digestive upset. Best all-purpose choice for keto. Take before bed.
Magnesium malate — better for energy and muscle function. Good for people who exercise on keto. Take in the morning or pre-workout.
Magnesium citrate — decent absorption but has laxative effect at higher doses. Use specifically for constipation issues on keto. Not your daily supplement.
Magnesium oxide — cheapest and most common but only ~4% absorption. Most of it goes through you unabsorbed. Causes digestive upset in many people. Avoid unless specifically used for constipation.
Magnesium L-threonate — specifically crosses the blood-brain barrier. Very expensive. Relevant for cognitive benefits, not essential for basic keto electrolyte needs.
My recommendation: Magnesium glycinate 300-400mg before bed. It's the clearest choice for most people.
Glycinate before bed changed my sleep quality dramatically. I sleep deeper and wake up with less muscle soreness. The sleep improvement is the most consistently reported benefit I've seen in this community — I'd specifically call this one out for anyone struggling with sleep on keto.
I use glycinate at night and malate pre-workout. The combination covers sleep quality AND exercise performance. Combined cost is about $15-20/month which is reasonable for the impact.
Ordered glycinate. The breakdown was exactly what I needed — the supplement store options were overwhelming without context. Thank you.