Buffered vs Unbuffered Magnesium Glycinate: Choosing the Best for Absorption & Digestion

When shopping for magnesium supplements in Australia, especially magnesium glycinate tablets or capsules it can be hard to know which option is best for your health. You might see two products labelled “magnesium glycinate” but notice big differences in price, dosage, and results. That’s because not all magnesium glycinate is created equal.

Some are pure, unbuffered magnesium glycinate, known for gentle digestion and superior absorption. Others are buffered magnesium glycinate, which blends in cheaper magnesium oxide - a form with much lower bioavailability that can act as a laxative in higher doses.

If you want the best magnesium glycinate in Australia for supporting sleep, muscle relaxation, mood, and hormonal balance, it’s worth knowing the difference. In this guide, we’ll break down buffered vs unbuffered magnesium glycinate, and help you choose the right supplement for better absorption and real results.

What Is Magnesium Glycinate?

Magnesium glycinate is a compound of magnesium bound to glycine, an amino acid. This form is highly regarded for its:

• Superior absorption (bioavailable)
• Gentle effect on the gut (less likely to cause diarrhoea)

• Support for sleep, mood, muscle relaxation, hormonal health + more

But here's the catch, not all magnesium glycinate on the market is pure.

What Does “Buffered” Magnesium Glycinate Mean?

Buffered magnesium glycinate typically contains a mixture of magnesium glycinate and magnesium oxide, a cheaper, less bioavailable form. This buffer increases the elemental magnesium content on the label but lowers the actual absorption rate.

Most consumers don’t realise that the magnesium oxide portion:

• Has poor bioavailability (only approximately 4% is absorbed)
• Acts as a laxative at higher doses
• Can irritate the gut, especially for sensitive individuals

In fact, magnesium oxide is primarily used as an antacid or laxative, not for replenishing cellular magnesium levels.

Why Don’t Brands Disclose This?

Unfortunately, current regulations don’t require supplement companies to disclose whether their magnesium glycinate is buffered - meaning the label can legally claim “magnesium glycinate” even if it contains significant amounts of magnesium oxide. In fact, most magnesium glycinate products on the market are buffered.

This lack of transparency can be misleading, giving the impression of a high quality, well absorbed product, when in reality, a large portion may consist of poorly absorbed oxide, which is cheap to use and offers minimal therapeutic benefit.

How to Tell If Your Magnesium Is Buffered

It's not always easy, but here are a few tips:

• Ask the brand directly: Reputable companies should be transparent about whether their product is buffered or unbuffered.
• Be wary of “too good to be true” pricing: Pure, unbuffered magnesium glycinate is much more expensive to produce. If the price is low and the elemental magnesium per capsule seems unusually high, there’s a good chance it’s buffered with oxide.

Why We Chose Unbuffered Magnesium Glycinate

At Maternally Happy, we believe in full transparency and formulating with purpose - not padding. That’s why our Pure Mag supplement contains only unbuffered, fully reacted magnesium bisglycinate. No oxide. No shortcuts.

We chose this form because it’s:

• Highly bioavailable
• Gentle on the digestive system
• Backed by evidence
• Pregnancy and breastfeeding friendly
• Trusted by practitioners

And most importantly, we want our customers to know exactly what they’re getting - and why it matters.

The Bottom Line

Buffered magnesium glycinate may look good on the label - but what your body actually absorbs is what counts. If you’re taking magnesium to support stress, sleep, hormones, or pregnancy wellness, it’s worth investing in the real thing.

Always read labels carefully, ask questions, and choose brands that are transparent about their formulations.

References

1. Walker, A. F., et al. (2003). Magnesium supplementation: effects on magnesium concentrations and clinical symptoms in women. Journal of the American College of Nutrition, 22(4), 276–282.
2. Lindberg, J. S., et al. (1990). Magnesium bioavailability from magnesium citrate, magnesium oxide, and magnesium chelate. Journal of the American College of Nutrition, 9(1), 48–55.

3. Cuciureanu, M. D., & Vink, R. (2011). Magnesium and stress. Nutrients, 3(11), 1102–1120.