Seaweed for teeth sounds like a stretch until you look at what else is on offer, which is mostly brushing a dog who does not want to be brushed. A powder that goes on the food is the version people keep doing, and that is most of what determines whether any dental product works at all.

The composition is one thing: 100% natural seaweed, Ascophyllum nodosum, hand-harvested in Ireland. The analysis gives protein 5%, crude fibre 4.5%, fat content 3%, crude ash 18.5% and moisture 11%, with natural iodine at 500 mg/kg and natural calcium at 1.3%. Bugalugs supply a spoon, and the instruction is to sprinkle the recommended amount onto food daily, mix and serve. They put results at 3 to 8 weeks of continued use.

• 70g or 200g tub with a spoon
• Single ingredient: hand-harvested Irish Ascophyllum nodosum
• Natural iodine 500 mg/kg, natural calcium 1.3%
• Protein 5%, crude fibre 4.5%, crude ash 18.5%
• Sprinkled onto food once a day
• Results stated at 3 to 8 weeks

Not for a dog or cat with a thyroid condition. Bugalugs put that warning on the tub and it is the important line on this page — seaweed carries iodine, at 500 mg/kg here, and iodine and thyroids do not mix casually. If there is any thyroid history, ask your vet before you start. Store it cool and dry and out of reach of children. And be realistic about what it does: it is aimed at preventing build-up, so tartar already hardened onto a tooth is a vet job rather than something a powder lifts off.

Who it's for: owners of a cat or dog who will not tolerate a toothbrush, and anyone wanting to stay ahead of plaque between check-ups.