I feed Izzy real food and some kibble for during the day. I also give him fresh fruits and veggies for snacks and he loves it! Human food is fine for them. Just make sure there is no salt or sugar added and there are some foods that they cannot eat, just like Yorkieluv mentioned.
Maybe your vet meant table food? I was told the same thing by other people and found out that the processed foods is what makes them sick. A lot of people were taught that human food is bad when in fact it is better for them than the dog food they sell in the stores. Yorkiedaze is the real food expert, definitely take her advice too! Good luck!