The UK’s Advertising Standards Authority banned an M&M’s Instagram ad in July 2026, ruling that the yellow M&M character — one of seven anthropomorphic mascots the brand has used since 1954 — constitutes an “identifiable, specific less healthy food product” under the Less Healthy Food advertising rules that came into law in January. The green M&M character, featured in the same ad, was ruled compliant. The difference comes down to shape. The yellow character is oval, which maps specifically to Peanut M&M’s. The green character is round, a shape shared across multiple M&M’s variants, so it cannot be linked to a single specific product.
Mars Wrigley argued that the characters represent the brand overall, not individual product variants, pointing to their “highly stylised” cartoon form with human traits — arms, legs, facial expressions. The ASA disagreed on the yellow character specifically, on the basis that its oval shape is distinctive to the Peanut product line. Three of M&M’s seven characters appear to be oval. All three are now effectively unusable in UK paid digital advertising or TV pre-9pm.
- LHF advertising rules came into force January 2026; the M&M’s ruling is among the first handful of enforced decisions
- Yellow and oval = Peanut M&M’s specifically. Green and round = multiple variants. The ASA’s distinction turned on shape alone
- Three of M&M’s seven mascots are oval-shaped and now face restrictions in paid UK digital and pre-watershed TV advertising
- The ASA ordered Mars to ensure the ad does not reappear and that future ads do not depict characters representing specific less healthy products
- Morley’s Woking, a fried chicken franchisee, was the only other upheld complaint in the same ruling — it had been unaware of the LHF rules entirely
Brand characters built around product shapes carry the identity of that product, not just the brand. M&M’s mascots have been marketing assets for 70 years — and the oval ones now have a specific legal liability in the UK. The ruling is a signal to any HFSS brand using character-led advertising: the more distinctive the character’s physical resemblance to the product, the less flexibility you have as advertising regulation tightens. The green M&M survived precisely because it’s less specific.




