Why is it harder to maintain weight level now than in the 80s?

I took the bus to school then as well but I also had to walk to the nearest school to be picked up by the bus which was a good 3/4 mile at least.

Now unless I want to add at least an extra 2 hours a day of total commute time if I take the bus (and thats $6 round trip which is way more than gas/maintainence on either the Prius or the scooter) I have to drive. Moving closer to work is not an option unless I magically get my salary doubled at the very least.


Canadians basically eat the same food as we do, but somehow they are much less obese. Why? well, we know there are far more “active commuters” in Canada than there are in the US. Maybe that has something to do with it.

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I keep reading the study, and I keep failing to see where people think physical activity was not taken into account. Seriously. Read it.

Self-reported physical activity was assessed using
questionnaires. In NHANES I and NHANES II, the
frequency of physical activity was not reported,
and therefore these survey years were excluded
from the physical activity and fully adjusted analyses.
NHANES III assessed if participants engaged in
physical activity in the past month, and if so, the
frequency of their participation in select moderate
and vigorous intensity activities (including walking,
jogging, bicycling, swimming, aerobics or other
forms of dancing, callisthenics, gardening or yard
work, and weight lifting) during their leisure time.
Individuals also had the option of listing up to four
additional activities. In the NHANES continuous surveys,
respondents provided additional information
on the frequency of moderate and vigorous intensity
activities, reported as times per day, week, or
month. Participants were also asked: (i) about walking
or biking as transportation to work, school or to
run errands; (ii) if they had performed home or yard
work that lasted at least 10 min and was at a moderate
or vigorous effort, and (iii) if they had engaged
in any moderate or vigorous leisure time activity.
For the purpose of this analysis, physical activity
from all surveys was converted to weekly bouts
of physical activity. All activities were assigned a
metabolic equivalent value (MET) [17], and only
activities that were of at least moderate intensity
(MET ≥3) were included in our definition of physical
To determine the magnitude of difference
between self-reported energy intake from NHANES
over time, we compared self-reported energy
intake to predicted daily caloric needs of each
participant using the sex-specific Harris—Benedict
equations [18], assuming a physical activity level of
sedentary and moderately active (3—5 days/week)
to obtain a reasonable upper and lower range for
predicted daily energy needs.

This means that the only (reasonable) assumptions made were about activity levels in the 80s. They collected data about physical activity in the present directly.


Ha, exactly, that’s a HUGE factor. This doc may be too soley focused on the vastly increased amounts of sugar in ordinary American diets, but still, it really opened my eyes:


Given often cited correlations between obesity and diet soda-pop intake, I also wonder if gut microbes have adapted to being able to break down the non-digestable sugar substitutes into something that the body can use.
edit: or is that what you were saying…


I think maybe you hit on why as you expanded your point – video games are just a special case of the general improvement in sedentary entertainment and how much it’s taken over our lives.

The study did make clear “even if exercise levels are the same”, so maybe it’s more about patterns of sedentary behavior. Like, being on our asses hours at a time.


I looked at the numbers: the decline of which you speak is pretty small. In 1980, 94% of the population did not bike or walk. In 2012, that number is 96%. Half as many people walked to work, but they certainly were not in any sense make a damn difference in the overall driving rate.

Plus, your stats show biking rates are up, too.

My argument is that the average person was probably just as lazy in the 80s. This study is arguing that given similar rates of reported activity, there should be similar reported weight levels.

It doesn’t matter who is driving or biking if you aren’t studying average activity rates (which they weren’t).

Personally, I am betting that there have been definitional changes that skew the results. Just look at how activity guidelines have sunk from “30 minutes of vigorous activity” to one I recently saw that asked people to just “be in motion for 30 minutes”.

If those represent the end points on a spectrum charting a single definition of physical activity, then the quality of that self-reported activity is naturally called into question.


I’m glad this is so blindingly-obvious to everyone that we get three different answers. :wink:

Snark aside, I do agree that the common element between the three answers (sitting) very likely has a strong effect.

There are numerous studies that have shown that even vigorous exercise every day does not erase the effects of sitting for several hours in a row each day.

Here’s the most recent article that was going around:

“Our Chairs Are Killing Us,” Say Researchers

Both sedentary behavior and lack of physical activity linked with non-alcoholic fatty liver disease (NAFLD) in large study of Middle-Aged Koreans, reports the Journal of Hepatology

… more than one half of the average person’s waking day involves sedentary activities associated with prolonged sitting such as watching TV and using the computer and other devices.

… regular high levels of physical activity do not fully protect against the risks associated with prolonged periods of sedentary behaviors

So regardless of whether people self-report the same number of hours of daily exercise, if we’re sitting for six or eight hours a day then it seems that this alone can explain a large number of ill-effects, without resorting to unproved speculation.


Not to keep touting the movie I referenced above, but its more poignant moments depict large kids who exercise like crazy, and (like their parents) just can’t understand why they can’t lose weight. Then they turn around and eat food and drink drinks that contain incredibly higher amounts of hidden sugar. Apparently, that crap (sugar) metabolizes differently; “calories in, calories out” is bullshit, because sugar calories, if I’m remembering right, go straight to fat much faster than others do.


IIRC, the initial concentration makes a big difference, too. It’s the difference between 25g of sugar in one go, versus spreading it out over the course of a day.


See that’s the thing, a lot of people can’t in the U.S. right now. Processed unhealthy food is way more cheap than fresh food, and if you’re already without enough money to really keep your family fed…what else are you going to do? Fresh food’s out of your budget.


Everything required more effort then.

  • manual typewriters
  • roll-up car windows
  • manual steering and brakes in cars
  • throwing quarters in a bin at toll-booths, no e-z pass!
  • fewer automatically opening doors
  • snowblowers, dishwashers, garage door openers etc were luxury items
  • rotary phones. Now, I don’t even need to dial 7 digits, I just tap a name.
  • getting up to change the channel
  • manual pencil sharpeners weren’t just a frauenfelder thing
  • “checking the mail”
  • “getting the paper”
  • “going to the bank”

Seriously, the surgeon general should require Amazon to list the calories that I don’t get to burn every time I buy a bottle of shampoo off Prime. I’m not writing it on a list, driving to the store, parking, walking the aisles, standing in checkout, returning home.


The greater hurdle to fresh cooking in economically disadvantaged areas in the US is the lack of grocery stores, not the cost of the veg.

@funruly: you’re either being facetious or are too young to remember all of the 80’s. :wink:


Oh heck as someone in an advantaged situation if I had to do all the cooking it would probably be a lot of premade/processed meals cause after spending 9 hours (8 + lunch) in the office and an hour commuting home I am not in the mood to do much for cooking most of the time.


In the US today, one might argue that one thing really hurting severely disadvantage people is the lack of land on which to do subsistence farming. With some of the dire poverty in the US, I have to wonder if that wouldn’t be an improvement.


I’m really curious if it’s anything to do with the dramatic increase in the use of HFCS, over regular sugar. If those “it’s not the AMOUNT of calories, but rather the TYPE of calories” folks are actually onto something.

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I feel like most people who could reliably do subsistence farming (not an easy task) could also get a minimum wage job. At $7.25 an hour, just six hours a day, five days a week (pittance, I know), that’s 217 McD’s hamburgers a week, or 54,250 calories a week.

Could most people farm 54,250 calories a week of food per person?

Cheap, bad food is way cheaper than growing your own, in terms of invested time, I believe.


Sort of, but the real problem in that area is the huge increase in BOTH.


actually since it is sweeter they can use less and once regular sugar hits your tummy the HCL very very quickly breaks it down to the same things.
the other big change that happened at the same time as HFCS was realizing that a lot of the cost for soda is sunk in the process and packaging not the amount of drink, so it costs maybe 1 cent more to upsize the drink but they charge you 20 cents more in pure profit. I can’t get a 12oz can of anything anymore from a vending machine at work and that will have more sugar than an adult needs in a day so even with regular sugar the 20oz bottle/supersize is an unhealthy calorie bomb.


Yes. The other, or another, cause for much higher sugar consumption is the ongoing “low fat!” craze. Gotta replace that lost taste with something. Solution? Dump in more sugar!