No. "Buffered" is the supplier's term for magnesium bisglycinate blended with a denser magnesium salt, usually magnesium oxide, to raise the magnesium per gram. It is a standard ingredient grade sold by the major chelate manufacturers, and it is permitted in India, the European Union, Canada and the United States.
The legitimate complaint is not buffering. It is buffering that the label does not declare.
Where the word comes from
Buffering is not a marketing invention by finished-product brands. It is how the chelate industry itself describes the grade. Balchem, which owns the Albion chelate business, sells magnesium bisglycinate in both original and buffered forms, and describes the buffered version as using an additional excess of magnesium oxide to combine a high elemental magnesium value with high bioavailability.
Other suppliers list the same thing. You will see anhydrous bisglycinate offered at roughly 13 to 14% magnesium and a buffered grade at 18 to 22%. Those are catalogue items, not shortcuts.
Why anyone buffers a chelate
There are three practical reasons, and none of them is deception.
- Capsule size. Delivering 121 mg of magnesium from pure bisglycinate takes about 864 mg of compound, which will not fit in one ordinary capsule. Buffering fits the same dose into one.
- Cost per serving. Glycine is the expensive part of the molecule and contributes no magnesium. A buffered grade lowers the cost of a given magnesium dose.
- Swallowing compliance. People who struggle with two large capsules a day often stop taking the supplement. One capsule is easier to keep up.
What buffering does to the arithmetic
Pure magnesium bisglycinate is 14.1% magnesium by weight at most, fixed by the molecule. Magnesium oxide is about 60.3%. Blend the two and the percentage lands somewhere between.
A 22% blend works out at roughly 83% bisglycinate and 17% magnesium oxide by weight. But because oxide is so much denser in magnesium, the magnesium splits far more evenly, close to 53% from the glycinate and 47% from the oxide. Most of the capsule is still glycinate; a little under half of the magnesium is not. Labels rarely make that distinction obvious, which is a fair criticism of the category.
Work it out for your own jar. The magnesium label calculator takes the two numbers off any label and shows both splits, by weight and by magnesium delivered.
Is the oxide portion wasted?
This is the usual worry, and it rests on a figure that does not hold up. The widely repeated claim that magnesium oxide is "only 4% absorbed" traces to a single urinary-excretion study from 2001 that did not test glycinate at all, and whose own authors concluded that inorganic salts can match organic ones depending on the preparation.
In the one randomised trial that compared magnesium bisglycinate against magnesium oxide head to head, absorption was similar in most participants. The chelate pulled ahead only in people whose absorption was impaired, and it was better tolerated across the board.
Tolerability is the honest advantage of a chelate, along with the glycine itself. Laxative effects from magnesium oxide appear at gram-level doses, far above the amount sitting in a blended capsule delivering around 120 mg of magnesium in total.
So what should you actually object to?
Undeclared blending, and only that. A product sold as "100% chelated" or "fully chelated" whose ingredient list names a single magnesium source, but whose arithmetic lands above 14.1%, is describing itself inaccurately. That is not a chemistry problem, it is a disclosure problem, and it has led to a recall in Canada and class action settlements in the United States.
A jar that says buffered, or that names both magnesium sources in the ingredient list, has told you the truth. You can then decide whether you want the single-source version or the one-capsule version. Both are defensible choices.
Choosing between them
| If you want | Choose | Trade-off |
|---|---|---|
| Bisglycinate as the only magnesium source | An unbuffered product around 14% | Two capsules per serving, higher cost per serving |
| One capsule a day | A buffered product above 14% | Part of the magnesium comes from a simple salt |
| Certainty either way | Whichever declares every magnesium source | None, this is just good labelling |
Related reading: 22% vs 14% magnesium glycinate, and what the percentage actually means. How much elemental magnesium is in 500 mg of magnesium glycinate?
This article is educational and is not medical advice. Magnesium supplements are not intended to diagnose, treat, cure or prevent any disease. Consult a qualified healthcare professional before starting any supplement, particularly if you are pregnant, breastfeeding, have kidney disease, or take prescription medicines. Percentages are calculated from standard atomic weights; commercial lots vary with moisture content.