People may be heavier than 50y ago, but people are also taller than they were half a century ago.
"...the average height of a man aged 20-74 years increased from just over 5-8 in 1960 to 5-9 ½ in 2002" [1].
Despite the higher weight, life expectancy has increased too [2]. I'm not trying to handwave obesity rates, but pointing out that it's a mixed narrative.
Nutrition is correlated with childhood growth. Was there a reason why how much they were fed would have changed with each individual, but not across the entire cohort?
Our heights are, in order, from oldest to youngest:
* 5' 7", same as our father
* 5' 9"
* 5' 11"
* 6'
Now obviously the sample size is quite small, but we've always wondered if nutrition had something to do with it.