Magnesium
Also known as: Magnesium, Magnesium Glycinate, Magnesiumbisglycinat, Magnesium Citrate, Magnesiumcitrat, Magnesium Threonate, ZMA
Mineral involved in muscle relaxation, sleep and blood pressure — where the form matters more than the dose, and cheap oxide is largely wasted.
Substance family
Vitamins, minerals, amino acids and enzymes. The recurring pattern: correcting an actual deficiency helps, supplementing beyond a normal level generally does not.
Effects on
Which outcomes this substance acts on — descriptive, not a recommendation.
Strain profile
Where this substance is most likely to hit — a rough orientation, individually dependent on dose, duration and predisposition.
This substance works against
Dosing & protocols by goal
Rough orientation ranges as reported in harm-reduction literature — not an individual treatment plan. Doses are individual and open-ended; frequency depends on the ester or half-life.
General supplementation
BasicDose
200–400 mg elemental / day
Frequency
1× daily, evening
Cycle length
Ongoing
Elemental magnesium, not the weight of the compound — 400 mg of magnesium citrate contains roughly 60 mg elemental.
Sleep and recovery
BasicDose
200–400 mg elemental / day
Frequency
1× in the evening
Cycle length
Ongoing
Glycinate is preferred here because glycine itself has a mild calming effect and it does not cause the laxative response citrate does.
Alongside stimulants or diuresis
IntermediateDose
300–400 mg elemental / day
Frequency
Split into 2 doses
Cycle length
For the duration
Relevant under clenbuterol or T3, where losses increase. Note that cramps under clenbuterol are usually a taurine problem rather than a magnesium one.
Side effect & countermeasure
Typical problems and what you can do to reduce harm — at a glance. Does not replace medical monitoring.
Problem
Oxide form is poorly absorbed
Countermeasure
Magnesium oxide is the cheapest and most common form and has a bioavailabilitybioavailabilityThe share of an administered dose that actually reaches the bloodstream intact. in the single-digit percentage range — most of it passes through. Glycinate, citrate or malate are considerably better. A high dose of oxide is not equivalent to a moderate dose of glycinate.
Problem
Confusing compound weight with elemental content
Countermeasure
Labels often state the weight of the compound, not the magnesium in it. 400 mg of magnesium citrate contains roughly 60 mg elemental magnesium. Read for the elemental figure, otherwise the actual dose is a fraction of what was intended.
Problem
Diarrhoea with citrate at higher doses
Countermeasure
Citrate draws water into the bowel — this is why it is used as a laxative. Glycinate avoids it and is the better choice for evening dosing.
Problem
Serum levels look normal despite depletion
Countermeasure
Only about one percent of body magnesium is in the blood, and the body keeps that fraction stable at the expense of tissue stores. A normal serum magnesium does not rule out depletion, which limits how useful the test is.
Problem
Impaired kidney function
Countermeasure
The kidneys excrete excess magnesium. With impaired kidney function it can accumulate, which makes supplementation a matter for a doctor rather than self-management.
Overview
Magnesium is involved in more than three hundred enzyme reactions, including muscle contraction and relaxation, nerve conduction and energy metabolism. It is one of the few supplements where a genuine intake shortfall is common rather than theoretical.
In this context it matters for sleep, muscle relaxation and blood pressure — and it is one of the few things worth taking regardless of what else is running.
Mechanism of Action
Magnesium acts as a natural calcium antagonist. Calcium triggers muscle contraction; magnesium is needed for the relaxation that follows. A shortfall shifts that balance towards tension — which is where the cramps, restless legs and difficulty relaxing come from.
The same mechanism explains the effect on blood pressure. Vascular smooth muscle relaxes with adequate magnesium; the effect is modest, roughly a few millimetres of mercury, but it points in the right direction in a context where several compounds push blood pressure up.
For sleep, magnesium influences the GABA system, the brain's primary inhibitory signalling. This is why the evening dose is the usual timing and why glycinate is preferred — glycine contributes its own mild calming effect.
Typical Context
Two to four hundred milligrams of elemental magnesium daily, taken in the evening. The two details that matter more than the dose are the form and the elemental content.
Magnesium oxide is the cheapest form, dominates the low-price market, and is absorbed in the single-digit percentage range. Most of it simply passes through. Glycinate, citrate and malate are considerably better absorbed, and the price difference is small enough that there is no good reason to buy oxide.
The elemental content trips up more people. Labels frequently state the weight of the whole compound — a capsule declaring "400 mg magnesium citrate" contains roughly sixty milligrams of actual magnesium. Anyone dosing by the front-of-label number is taking a fraction of what they think.
One thing worth naming for anyone running clenbuterol: cramps in that situation are usually a taurine deficiency rather than a magnesium one. Magnesium is still worth having, but if cramps persist despite it, taurine is the more likely answer.
Side Effects & Risks
- Diarrhoea, particularly with citrate at higher doses
- Digestive upset
- Accumulation with impaired kidney function
- Very well tolerated otherwise
- Interaction with certain antibiotics — space several hours apart
Blood Work & Monitoring
- Magnesium (serum) — of limited use; a normal value does not rule out depletion, since only about 1% of body magnesium is in the blood
- Kidney values (creatinine, eGFR) — relevant before longer-term supplementation
- Blood pressure — measured at home
Harm-Reduction Notes
- Buy glycinate, citrate or malate — not oxide, which is largely wasted
- Read the elemental content, not the compound weight
- Glycinate in the evening; citrate can cause diarrhoea at that dose
- A normal serum value does not prove adequate stores
- With impaired kidney function this belongs with a doctor
- If cramps persist under clenbuterol, the missing piece is usually taurine
Legal status by region
Regulation differs considerably between jurisdictions and changes over time. This is a rough orientation, not legal advice — check the rules that apply where you are.
| Region | Regulatory status |
|---|---|
| United States | Dietary supplement |
| EU / UK | Food supplementUpper intake limits apply. |
| Most other jurisdictions | Freely available |
| Competitive sport | Not prohibited |