The one number that matters: 20ppm

'Gluten-free' is not a marketing phrase — it is a regulated claim. Any product carrying it in the UK and EU must contain 20 parts per million of gluten or less, a threshold set because research shows it is safe for people with coeliac disease. If the words are on the pack, the law stands behind them.

Know your label tiers

  • Certified gluten-free: carries a mark like the Crossed Grain symbol — the recipe and the factory are independently audited.
  • Labelled gluten-free: the legal 20ppm claim, tested by the manufacturer.
  • 'No gluten-containing ingredients': the recipe has no gluten sources, but the product has not been tested — caution advised for coeliacs.
  • 'May contain wheat/gluten': a voluntary cross-contamination warning. Risk varies by manufacturer; coeliacs should generally avoid.

The ingredient names that hide gluten

Wheat, rye, barley and oats (unless certified gluten-free) are the obvious four. Less obvious: spelt, kamut, semolina, couscous, malt extract, malt vinegar and brewer's yeast. Allergen law requires gluten grains to be emphasised in bold in the ingredients list — so scan for bold text first.

Oats are a special case

Oats are naturally gluten-free but routinely contaminated in the field and mill. Only oats specifically labelled gluten-free are safe for coeliacs — and a small minority of coeliacs react to avenin, the oat protein itself.

Build the 10-second habit

Front of pack for the claim, back of pack for bold allergens, then the may-contain line. Ten seconds, three checks — it becomes automatic faster than you'd think.