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Can I give my 15 kg dog a spoonful of plain yogurt every day for weeks, or will the live cultures and lactose eventually cause diarrhoea or weight gain?

Dogs · Food safety

Last reviewed: 2026-09-05 · Reference ranges: ASPCA, Pet Poison Helpline & Merck Veterinary Manual

Short answer

A daily spoonful of plain, unsweetened yogurt is generally safe for a 15 kg dog, but watch for loose stools or increased gas after 1–2 weeks—the lactose can accumulate even in tolerant dogs. Live cultures may actually help fibre digestion, yet the extra calories (about 15–20 kcal per spoon) can add up to 100+ kcal weekly, potentially causing gradual weight gain if his regular meals stay unchanged. Rotate yogurt with other low-lactose treats like pumpkin puree, and schedule a weight check with your vet every month during long-term feeding.

Plain yogurt — Food safety facts

Safe to share · Dogs · full breakdown on the linked food page

Plain, unsweetened yogurt with live cultures is safe in small amounts. Avoid anything with xylitol or artificial sweeteners.

Dogs and cats carry the same rating (Safe to share), so the notes below hold for either pet.

Plain yogurt is not toxic to dogs. The real limit is calories, fat and salt, so treat it as a small extra alongside the normal ration rather than a meal in itself.

There is no poisoning risk here, and the usual problem is simply eating too much at once: a heavy fat or salt load can bring on loose stools or a single vomit. Offer water, keep an eye on the pet for 24 hours, and do not induce vomiting.

Why these cautions matter

Even a gram or two of xylitol can trigger a sharp drop in a dog's blood sugar, and larger exposures go on to damage the liver.

Added sugar brings empty calories, and over months that means weight gain and dental disease — both far harder to undo than to avoid.

Plain yogurt can stay on the rotation, but only as an extra mouthful: keep the rest of the day's food unchanged and watch the next walk and the stool that comes with it.

The full verdict, portion guidance and serving notes are collected on the Plain yogurt food facts page.

Open the full food page: Plain yogurt food facts →