Can Dogs eat ...?
Food safety index

Kale is not acutely toxic to dogs, but it contains several naturally occurring compounds — oxalates, isothiocyanates, and calcium oxalate — that can cause digestive upset and, with large or repeated servings, more serious issues including kidney irritation and thyroid interference. Small amounts of plain kale fed occasionally are unlikely to harm a healthy adult dog. Owners of dogs with kidney disease, hypothyroidism, or a history of bladder stones should avoid kale entirely.

Spinach is not acutely toxic to dogs and offers genuine nutritional value, but it contains high levels of oxalic acid that can interfere with calcium absorption and, in large or repeated amounts, may stress the kidneys. For healthy dogs, small occasional portions are fine, but dogs with existing kidney disease or urinary problems should avoid it entirely. Moderation is the key word here.

Bell peppers are safe for dogs and offer genuine nutritional benefits, including vitamins C and A, with no toxic compounds present in any colour variety. Red, yellow, and orange bells are the most nutritious choices, while green peppers are slightly more bitter and lower in antioxidants but still harmless. The only real concerns are overfeeding, which can cause mild digestive upset, and ensuring the stem and seeds are removed before serving.

Cucumbers are one of the safest vegetables you can share with your dog — low in calories, high in water content, and free of any known canine toxins. Even larger amounts are unlikely to cause anything more serious than mild digestive upset. They make an excellent crunchy treat, especially for dogs that need to watch their weight.