What your mother told you may not be correct.
Some things may not need to be passed down to yet another generation.
Mom's Rule: Eat more, kids are starving everywhere!
Yes kids are starving everywhere, but probably not in your house. It's important to give kids the chance to stop eating based on appetite instead of visual cues like a clean plate or empty bowl. When they lose the connection between stopping their meal when they're full not when it's gone the risk of becoming overweight goes up.
Mom's Rule: Don't sit close to the tv, you'll ruin your eyes.
Actually you won't. Kids can't harm their eyes by sitting with their noses presses against the screen. Watching close up can cause eye strain which may lead to headaches. It doesn't worsen vision, but it's not comfortable either.
Mom's Rule: Don't frown, you'll get wrinkles.
Yeah you might. Showing that sad face millions of times over in your life may leave a line or two eventually, but so can laughing. There's no way to avoid it, nor any reason to try.
Mom's Rule: Put on your coat, you'll catch a cold.
The only thing your kid is likely to get from being outside in the cold is...cold. Only cold and flu viruses can cause those illnesses.
Source: www.cnn.com