> actually the number one hidden danger in the modern diet.
As opposed to a sedentary lifestyle spent passively consuming entertainment from the safety of environmentally controlled living spaces that requires little energy to be expended on any activities.
That theory does not stand the test of time or geography.
US obesity rates and dental problems started skyrocketing around war time, when sugar was introduced to soldiers' rations and by virtue of subsidies into mainstream diet. Many of life's comforts like cars or TV sets (and radios before them) were available in that era.
At the same time countries with low obesity rates exist today, and residents of Thailand, Moldova or Japan are not particularly deprived of cars, TVs or PCs, nor do they exert significant physical effort to hunt and gather their food.
On the other side of the spectrum, countries with high obesity rates (Mexico, Nauru, Cook Islands) are not particularly car-infested way way higher when compared to peers, nor do they have extreme TV/PC consumption numbers.
The only relevant variable seems to be the amount of sugar (consumed from all sources) in the diet.
The sedentary lifestyle theory does help sell fitness club memberships, though, so it's not completely useless.
You can't use possession of cars as a proxy for sedentaryness. If you look at the number of people on sidewalks in the US (approximately none) versus the number of people walking in Japan or Thailand, you'll see a stark contrast. In the US, people (myself included) will take a car to the grocery store a ten minute walk away. In most cities around the world you get used to walking places, but since it's rarely feasible to walk in the US, you get used to driving everywhere.
The closest they came to testing that hypothesis was to conduct surveys across residents of various countries, and it turns out the "laziest" countries are not the obesity leaders (although arguably laziness here is self-reported)
I don't know if anyone has good data on the amount of walking per capita per country. Maybe FitBit would have decent stats, but then their userbase is a bit self-selecting.
Sugar was being consumed just a heavily before the war. It only became a demonized, food shaming tool because of rationing propaganda that warned (read lied to) mothers of the dangers of too much sugar. Thus the fictitious "sugar high" was invented and seized upon by nutrition "experts" to build a massive industry that depends on playing the blame game on so called bad foods that get reshuffled each decade or so. Everyone is suckered into blaming their food rather than their behavior and the people making billions off of this scheme aren't about to reveal the truth.
Those people did exist, but were largely ignored because the medical bureaucracy and Federal government got into the food pyramid and dietary guidelines business.
The real money for the food industry then became pursuing the low-fat diet.
It's only been recently that the medical community has realized that sugar is actually the number one hidden danger in the modern diet.