Which foods must guinea pigs never eat?

Short answer: onion, garlic, leek, chives, avocado, chocolate, potato (sprouts and skin), dairy, meat and human snacks are all off-limits.

1. Allium family — onion, garlic, spring onion, chives can affect blood health.

2. Fatty or stimulating — avocado, chocolate, coffee, tea.

3. Unsuited to herbivores — meat, eggs, milk, cheese, bread, biscuits, nuts and seeds.

4. Plant risks — green potato skin and sprouts, houseplants, unknown wild weeds.

5. If eaten — note what and how much, then contact an exotic-pet vet promptly.