Sunday, December 14, 2008

U.S. Weight, Lifestyle and Diet Trends, 1970- 2007

For this post, I compiled statistics on U.S. weight, health and lifestyle trends, and graphed them as consistently as possible. They span the period from 1970 to 2007, during which the obesity rate doubled. The data come from the National Health and Nutrition Examination Survey (NHANES), the Behavioral Risk Factor Surveillance System (BRFSS), and the U.S. Department of Agriculture (USDA). Some of the graphs are incomplete, either because the data don't exist, or because I wasn't able to find them. Obesity is defined as a body mass index (BMI) of 30+; overweight is a BMI of 25+. Yes, it's frightening. It has affected adults and children (NHANES).
The percentage of Americans who report exercising in their spare time has actually increased since 1988 (BRFSS).
We're eating about 250 more calories per day, according to NHANES.
The 250 extra calories are coming from carbohydrate (NHANES).

We're eating more vegetables and fruit (USDA).
We're eating more meat by weight, although calories from meat have probably gone down because the meat has gotten leaner (USDA). This graph represents red meat, fish and poultry. The increase comes mostly from poultry. Boneless, skinless chicken breasts anyone?
We're eating more sugar (USDA). The scale of the graph doesn't allow you to fully appreciate that sweetener consumption had increased by a full 100 calories per day by 1999, although it has dropped a bit since then. This is based on food disappearance data. In other words, the amount consumed is estimated using the amount sold domestically, minus a percentage that approximates waste. High-fructose corn syrup has seized nearly 50% of the sweetener market since 1970.
Again, the scale of the graph doesn't allow you to fully appreciate the magnitude of the change here. In 2000, we ate approximately 2.5 ounces, or 280 calories, more processed grains per day than in 1970 (USDA). That has since decreased slightly (34 calories). You might be saying to yourself right now "hey, that plus the 100 calories from sugar adds up to more of an increase than the NHANES data show!" Yes, and I think that points to the fact that the data sets are not directly comparable. NHANES data are self-reported whereas USDA data are collected from vendors. Regardless of the absolute numbers, our processed grain consumption has gone way up since 1970.

Wheat is still king. Although we grow a lot of corn in this country, most of it gets fed to animals. We prefer eating wheat without first feeding it to an intermediary. In absolute quantity, wheat consumption has increased more than any other grain (not including corn syrup).
Bye bye whole milk. Hello skim milk (USDA).

This graph represents "added fats", as opposed to fats that occur naturally in meat or milk (the USDA does not track the latter). Added fats include salad oil, cooking oil, deep fry oil, butter, lard, tallow, etc. We are eating a lot more vegetable oil than we were in 1970. It comes chiefly from the industrial, omega-6 rich oils such as soybean, corn and canola. Added animal fats have increased slightly, but it's pretty insignificant in terms of calories.

There is an artifact in this graph that I have to point out. In 2000, the USDA changed the way it gathered vegetable oil data. This led to an abrupt, apparent increase in its consumption that is obvious on the graph. So it's difficult to make any quantitative conclusions, but I think it's clear nevertheless that vegetable oil intake has increased considerably.

Between 1970 and 1980, something changed in the U.S. that caused a massive increase in obesity and other health problems. Some combination of factors reached a critical mass that our metabolism could no longer tolerate. The three biggest changes in the American diet since 1970:
  • An increase in cereal grain consumption, particularly wheat.
  • An increase in sweetener consumption
  • The replacement of meat and milk fat with industrial vegetable oils, with total fat intake remaining the same.
Mainstream America has done to itself what it did to native American and other indigenous cultures worldwide, with the same result.

20 comments:

David said...

You can ride articles from the 50's and 60's, not to mention the 70's and 80's, bemoaning the huge increase in society and claiming that everyone in society is obese. I'm not sure an increase in obesity is any more or less real now than in the past.

David said...

*read*, not ride

Methuselah said...

Superb post Stephan - never seen these figures so well represented or more clearly explained. This is one for the favourites for sure.

Jeff said...

Hey Stephan,

Great post, as usual. One item that I think might also contribute is the intake of artificial sweeteners. I would guess that they have gone up huge in the last 40 years, starting with saccharine and lately with splenda and nutrasweet. Do you have any numbers on that?

I know very few overweight people that aren't heavy users of diet soda in particular. My guess as a layman is that these in some ways are worse than sweeteners:
1) The illicit the same or similar insulin response.
2) The glucose the insulin is there for isn't there as much, resulting in an overreaction to the caloric intake, resulting hunger/bonking, and then increased eating at the next sitting or as in between snack on something bad.
3) People believe it is healthier and thus use more of it.

The fact that these fool the body make it a good candidate for messing up metabolism. Any thoughts?

jeff

PS Like an earlier comment, I get excited every time a new post from you comes on my google reader. This is seriously the best of a lot of good bloggers on diet and health.

Jenny said...

Stephan,

Several important things are left out here.

SOY. Graph the amount of soy added to food, and you should see a dramatic rise. Soy slows the thyroid and is an estrogen mimic. Both of these lead to weight gain.

PLASTICS IN BLOODSTREAM. Exposure to plastics like Bisphenol0A leaching into food is a major, undiscussed reason for obesity. Animal studies show exposure in the womb is particularly dangerous and has lifelong implications. With plastics lining cans and leaching out of microwaved foods and baby bottles, we have a huge metabolic disrupter here.

Studies done in the middle 20th century showed that healthy toddlers would not overeat no matter how much food they were exposed to. The early onset of overweight in children is much more likely due to chemical disruption of their metabolic regulatory systems than "lifestyle choices."

There are too many lawsuits hidden here for anyone with money to fund the studies needed to identify these true causes of the obesity epidemic.

Blaming the victim is so much easier!

Dr. B G said...

Stephan,

It's obvious you spent a lot of time and thought on this. Hopefully it can be published somewhere (Nutrition and Metabolism?). Men's Health had a similar graph with with omega-6 veggie fats (I believe). I've seen a similar graph with adenocarcinoma (deadly) esophageal cancer and fructose introduction to the U.S. food supply.

Excellent!! How can you surpass yourself? You just did.

-G

Anna said...

And right about the time all those factors reached the "perfect storm" conditions in the 70s-90s, the baby boomers began to hit middle adulthood. Years of damage begins to overtake youthful ability to rebound, and shows up as expanding waistlines and disease.

Stephan Guyenet said...

Jeff,

Good point. I do think artificial sweeteners are a problem. They can cause weight gain in rats. I don't have data on those but it might be worth looking up.

Jenny,

True. I'm going to do a post on endocrine disruptors at some point. Thanks for introducing me to that issue.

I believe what you say about healthy toddlers from decades ago not overeating. That's how our bodies should work. That could potentially be accounted for by factors in the diet, such as less n-6 and less sugar. Our body fat contains more than twice the n-6 it used to. As you mentioned a while back, processed food used to contain lard and tallow rather than vegetable oils.

I tend to focus on the toxins we stuff our faces with rather than the ones that hitch a ride on our "food".

Calvin said...

Stephan, Excellent post--the graphs really enhance it. I'd be interested in data comparing changes between consumption of processed foods with unprocessed (real food vs frankinfood).

Jenny, I'm on board with your comments--anything that depresses thyroid slows the metabolism. From an oversimplified perspective (e.g., not including hormonal response, satiety, allergic reactions to foods, homeostasis, etc . . .) take a 2400 kcal/day diet--that's ~100 kcal/hour metabolism, say that thyroid efficiency is reduced 10% by a synergistic combination of exogenous factors [e.g. soy, chemicals, etc] that's 240 kcal/day--now plug that back into any of Stephan's graphs--hypothetical, but still worth consideration.

Also, I agree with Jenny and think that one has to consider not only the ever-increasing ubiquity of plastics (e.g., bisphenol A, phthalates, etc.), and myriad xenoestrogens, but also the interactions they have with regards to metabolic syndrome and obesity as well.

David, I don't have to read articles from several of the past decades discussing the increase of obesity--that always makes mews and sells. In these same articles have you looked at photos of what used to be considered obese, and compared that with the current norms? Just one example of increasing obesity becoming the new norm, is buying shirts/jackets to fit my chest/shoulder dimensions while still fitting my 32" waist dimensions--seems all manufacturers have increased the wait dimensions to fit the ever popular "wheat belly"--much to my dismay and my seamstress delight.

Calvin said...

Stephan,

Your last reply post just beat me to my last post. Do you have psychic abilities too :)

I think that looking at just macro/micro nutrients an how they affect health w/o looking at endocrine disruptors is analogous to looking at a few individual tree w/o seeing the forest. Yes, it's complex, but there are feedbacks, interrelationships, etc. to consider . . .

Also, I'd love to see the erudite, engaging, witty . . . Dr BG over at: Animal Pharm http://drbganimalpharm.blogspot.com/
get in on this subject too.

Unknown said...

Interesting collection of data that confirms what many of us know about processed foods. I think in addition to diet there's also changes in typical food consumption and production patterns over time such as portion size, frequency of snacking or eating out vs cooking and a general push towards more consumption and profiteering by politicians and corporations.

Stephan Guyenet said...

Calvin,

I agree, there may be many factors. But I think there are a few "elephants in the room" that are doing most of the heavy lifting. For example, when people go low-carb or paleo, they often see major weight losses. So I tend to point my finger at things that, when eliminated, solve the problem.

David said...

Do Japanese and Chinese consume a smaller share of calories from carbs or processed carbs than Americans? I doubt it, yet they are much thinner than we are. Do poor and uneducated Americans consume more carbs than rich and well-educated Americans? Again, I doubt it, yet the rich and well-educated tend to be thinner in the USA. Most of my friends are professionals and almost all tend to favor a low-fat diet, yet none are fat.

Anna said...

"Do poor and uneducated Americans consume more carbs than rich and well-educated Americans?"

Yes, they generally do! Sugary and starchy processed carb foods are typically the cheapest foods, not to mention often the lightest and easiest to transport when getting around on a bus or walking, as well as being non-perishables.

Ever volunteer for a food drive for the local food assistance pantry? Most of the food donated is empty starch calories, like canned corn, pasta, rice, powdered potatoes, boxed cereals, crackers, cookies, and so on (I make it a point to donate canned salmon and tuna pouches because so little protein foods are donated).

And every media article I see lately on the topic of stretched food budgets for the weak economy are promotions for foods that concentrate on pasta, rice, beans, cereals, "canned" dough products, tortillas, etc.

And Asians are fighting the battle of the bulge, too, but they got a later start than Americans, so their gains (bulge) aren't quite so obvious yet compared to ours. The youngest Asian generations in particular are going to have a hard time, too, as they are consuming a lot of western foods now, and more wheat and sugar than their parent's and ancestors ever did. There's almost no place on earth one can't get a Coke these days, and American fast food franchises are seemingly everywhere, too. The young people all over flock to them.

Stephan Guyenet said...

David,

The point is not that we are eating more carbohydrate, but that we are eating more of the wrong type of carbohydrate.

The Japanese do eat a lot of polished rice without gaining weight (although overall they actually do eat less carbohydrate than Americans). I think that points to the fact that rice is less problematic than wheat.

As Anna said, poor people in the US definitely eat more processed carbohydrate (soda, candy, donuts, etc) than wealthier people on average. They also eat more low-quality vegetable oils.

Again, it's not about the quantity of fat, it's the type of fat. We aren't eating more fat in the US than we did in 1970. We're eating industrial vegetable oils rather than animal fat.

If you look at the diet of poor Americans, it's fairly similar to the diet on many N American Indian reservations. Lots of white flour, vegetable oil, sugar, alcohol. Both populations suffer from a very high obesity rate as well as other problems.

Valda Redfern said...

"I'm not sure an increase in obesity is any more or less real now than in the past". I am - every time I see TV footage or photos from the early 1970s. People looked so skinny then! And Calvin is right, the standard clothes sizes used now are bigger and differently proportioned to what they used to be.

Joseph Martini said...

How about: All of the above, combined with a completely sedentary lifestyle.

Back in the 1950s (I was 7 or 8 years old) my uncle gave me a body-building guide for my birthday.

In the first chapter it said that building and maintaining lean muscle mass is the best way to control weight. I'll be 60 very soon and I'm 5'9", 158 pounds with a 30" waist.

My uncle? He's 70 and still looks like he can tear down a house with his bare hands.

All of the most recent studies show that the "Aerobics" fad that started in the 70s does virtually nothing to enhance fitness. Short, intense workouts do the trick.

Once again, thanks for nothing Jane Fonda.

Lindybill said...

Great graphs! I have no doubt this rise in obesity and type II diabetes started with the Cardiologists, back in the 50's, announcing that the best diet was a low fat one with low cholesterol.

We are now wising up to the fact that the way to go is the original "Banting" diet that Banting wrote about in the 1850's. Low Starch and no sweets. That's what "low carb" is.

Jon said...

I know this is an old posting, but I'd still like to say that this information is very, very enlightening when brought to one web page. Kudos, and please do update if/when it is possible.

BruceGray said...

Over this period the following also happened, any of which could be reasonably concluded to contribute to energy imbalance:
- from the mid 70s, late night television viewing became more common.
- as did watching morning television shows. Prior, people listened to the radio and exercised more.
- family size got smaller.
- car ownership and commute times lengthened.
- work time increased.
- debt increased (from education and car and home ownership)
- religious affiliation fell dramatically.
- recreational drug use became normalized and widespread.
- self control diminished. hyperactivity disorders increased.
- vaccination and immunization increased.
- sex and sexually transmitted diseases increased.
- women's liberation increased.
- women in the workforce (and notin the kitchen) increased.
- recreation became less rooted in local community and more about watching television, then the internet.
- alcohol consumption increased.
- home prepared meals decreased (breakfast,lunch,dinner).
- coffee consumption went up.
- a welfare state mentality increased.
- egalitarianism in wages decreased.
- job security decreased (I had friends who retired from GM and Ford in the 70s who were very well taken care of).


Any or all of the above could be blamed for the obesity epidemic.