Cabbage can provide some fiber and lots of vitamins and minerals. It has plenty of vitamin C, vitamin K, potassium, magnesium, and beta carotene (a precursor of vitamin A). As is true of many vegetables, it also has plenty of antioxidants. Plus, many dogs enjoy crunching on small pieces of cabbage.
Dogs can eat raw cabbage, but that should be fed in relatively small amounts. Both red and green cabbage are acceptable. The fiber in cabbage can help with both constipation and diarrhea, but too much, especially raw, may cause some constipation.
Dogs can have cooked cabbage too, but if you decide to cook some cabbage for your dog, note that cabbage cooked for dogs should be plain. The added spices, butter, and other things that you enjoy are often not good for your dog.
Feeding cabbage to dogs does have some drawbacks. Cabbage is well known for flatulence. If your dog is already a bit of a social outcast for his flatulence, adding cabbage will only makes things worse. In addition, excessive gas production in the gastrointestinal tract may contribute to bloat or gastric dilatation/volvulus, commonly termed “GDV.”
You should be aware that feeding cabbage adds thiocyanate to your dog’s diet. This compound can have adverse effects on the thyroid gland, so dogs who are already hypothyroid ought to skip their cabbage snack.
Cabbage is a cruciferous vegetable, like broccoli and cauliflower, which means it adds calcium oxalate to your dog’s diet. If your dog is a one of the breeds or mixes that are prone to forming calcium oxalate stones or crystals in his urine, he is better off skipping all those vegetables. Affected breeds include Bichons, Miniature Schnauzers, Lhasa Apsos, Yorkshire Terriers, and Shih Tzus.
Bottom line: Small amounts of cabbage are fine for most dogs but consider using it as an occasional treat.