Eat or Pass? 2. Milk We commonly tend to think that milk is a balanced food choice to fulfill all nutritional needs, and we tend to feed it to street dogs and our pets, BUT here's a plot twist. Most Dogs are lactose intolerant and cannot digest milk. It can cause negative reactions like vomiting, diarrhea, and loose stools. They don't even need milk nutritionally after the weaning period. Other dairy products like curd and cheese are easily digestible but are better to be fed in moderation.