Hey lovely parents, need some help with a formula question!?

So my son just turned 1 on tues and the doc said that i can now give him whole milk instead of formula, to me that seems harsh lol! maybe i'm being a crazy mother (this is my one and only baby!) but i feel like he loves his formula. he actually prefers it over "real people food" and esp prefers it over those gerber jars! am i doing something wrong that he likes formula this much? is it wrong that i don't want to cut him off? i feel comfortable with the formula because i feel like it has more nutritional value than just plain milk but i may be wrong? he is 32 inches talk and weighs 21.5 lbs, when he was born he was 20 inches and 6lbs, so yea he grew alot but his diet mainly consists of 4oz of formula every 3-4 hrs (besides at night because he sleeps a min of 10 hrs at night and up to 12 whole hrs!) which he has been eating since he was just 3 months old! he eats maybe one gerber jar a day and then eats some of whatever i am eating throughout the day but not too much! i am pretty small 2 5'3 and about 105 and his dad is 6'4 250 so i don't know if he maybe just has my appetite? sorry this is so long and confusing and thank you guys for all your insight! have a wonderful day!