Why the 6kg cat's avoidance is actually helpful
Your larger cat's disinterest in beetroot cubes eliminates any risk for him—no need to monitor or intervene. Cats self-regulate plant intake instinctively, and his refusal suggests he either dislikes the earthy aroma or feels no digestive need for extra fiber. At 6kg, his body weight provides an additional buffer; even if he'd eaten the same two cubes, his processing capacity would be 50% greater than his 4kg companion's.
The 20-minute timeframe confirms the beetroot-eating cat is past the point of potential regurgitation from novelty. Had either cat reacted negatively, you'd have seen drooling or head-shaking immediately post-ingestion. Their differing responses highlight how individual feline preferences dictate safe exposure more than blanket toxicity rules.
Digestive contrasts between your two cats
The 4kg cat who ate the cubes may pass slightly red-tinged stools tomorrow—this is harmless pigment, not blood. Her smaller size makes her slightly more prone to digestive changes, but two cubes equate to less than 5% of her daily food volume. Meanwhile, the 6kg cat maintains his usual digestion; no need to adjust his meals to 'balance' anything.
Watch for resource guarding if one cat enjoyed the treat and the other didn't—some felines become possessive of novel foods. Separate their feeding areas temporarily to prevent conflict, though the beetroot itself won't cause aggression. The non-eating cat might sniff his companion's breath curiously later, which is normal investigation behavior.
When shared meals become risky versus benign
This incident demonstrates how harmless food sharing can be when the substance is non-toxic and portions are tiny. Contrast this with dangerous shared meals like onion-containing sauces—there, even the non-eating cat would need monitoring if bowls were licked clean. With plain beetroot, the only concern is ensuring the 4kg cat doesn't start seeking out human food more aggressively.
The cubes' cooked state makes them safer than raw beetroot, which has tougher cellulose that can irritate feline guts. Neither cat needs digestive enzymes or probiotics after this event, though you might notice the beet-eating cat's stool smells earthier tomorrow. This will pass within one bowel movement.
Future prevention for mismatched feline eaters
Since one cat shows interest in human food while the other doesn't, store beetroot and similar veggies in lidded containers immediately after use. The 20-minute window before you noticed the consumption suggests quick cleanup could prevent repeats. Neither cat requires a vet visit, but the incident highlights their different scavenging tendencies.
For the curious cat, consider offering cat-safe greens like wheatgrass as an alternative outlet. The disinterested cat may simply prefer protein-only treats—a common feline trait. Their weights aren't factors in this preference; it's purely individual personality determining which smells appeal to them.
The full verdict, portion guidance and serving notes are collected on the Beets food facts page.