7. Citrus

Your canine companion must be kept away from citrus foods as citric acid can “cause irritation and possibly even central nervous system depression if ingested in significant amounts”, says ASPCA.  The source adds that not only the fruit itself, but it also includes the stems, leaves, peels and seeds of citrus plants which are liable to have different amounts of citric acid. Although small amounts of consumption do not have a big effect it can still cause tummy issues in certain dogs.