Mc Donald’s existed when I was a kid. So did junk food, and even video games. And I was still not fat.
I’m guessing your parents didn’t allow McDonalds do all the cooking for your home. I know my urban friends seldom cook when they have a dozen fast food places within a couple of blocks of their home.
The last time I had fast food was about two years ago when I stopped on my way home from the upper peninsula.
1. We didn’t use to buy as much junkfood, even if it was there.
McDonald’s was an occasional treat, not a daily thing. Junk food existed, too, but it was also an occasional treat, or something I had to use my own money to buy.
2. We didn’t eat as much processed/unsatisfying food.
Parents who are too often resorting to dino-nuggets and other prepared foods for dinner are feeding kids a lot more salt and fat than they think, and very little fiber. That stuff revs up appetite instead of satiating it.
Also, that nasty high-fructose corn syrup wasn’t in our food back then. I’ve read that, when you drink a soda made with it, your body doesn’t recognize that it just ate 120 calories. It thinks it just drank water. People are unwittingly Big Gulping their way to disaster because of HFCS. Soda companies are now experimenting with bringing back sugar. I just read that Dr. Pepper will be doing that for it’s 125th anniversary.
3. We were outside more.
Maybe it’s not just the exercise, it’s the going outside to play for long periods of time, where you are not near the junk food. My parents threw me outside to play most of the time, in a big back yard. There was food out there, but it was fresh fruit. Now, it’s not perceived as safe to let your kids play in the front yard, or walk over to the park by themselves, or walk to school. Parents are truly terrified of abductions, even if they are statistically very rare. Also, there’s no one to play with, so many people have one kid, and that kid is in after-care or at scheduled activities. We have a cul-de-sac at the end of our street. Even though kids live in the houses around the cul-de-sac, they never come out to play together.
4. Stay-at-home moms made a difference.
They were more likely to cook foods that had fiber and less salt and fat.
They were home in the afternoon to supervise (enforce) outside play and make snacks.
They didn’t have to drop the kids off on the way to work and pick them up at aftercare, so they could walk with the kids to school or let them walk by themselves, and mom was home when they got home.
With more people at home during the day in the neighborhood, it was less safe for creeps to lurk around, ready to grab an unwary junior high girl or a little boy (recent crime attempts in my area). My mom was Neighborhood Watch before it was ever invented.
That being said, I was not a skinny kid, but all of the above kept me in regular sizes, not “pretty plus”. Fat kids were rare, maybe one in your class every year.
I think there is more than one reason. Kids today can’t go outside and PLAY like we did. When I tell my kids that I ran outside after breakfast and we would run, swim, play in the neighborhood ALL day, they are amazed. I do not let my younger kids outside without an adult now. TOO many pedophiles and that concern. Also, my mom was a stay at home mom like all of my friends’ moms. They cooked real food. Nothing was fast or processed. It was baked chicken over microwave nuggets, mashed potatoes over french fries, and real vegetables (nothing from a bag with chemical sauce). We had two choices for a drink: milk or water. Kids today also have hours of homework. In comparison, I had maybe a half an hour over my ten year olds two plus hours. Homework that extended past an hour was for high school so we still played during the winter. Fast food was a once a month treat (not a weekly thing like today). As for junk... Mom baked something two to three times a week but it was burned off. Just a thought since this has been a topic of discussion in my family...