Near the entrance to SeaWorld San Diego’s popular Manta roller coaster stands an actual seat from the attraction. It’s there to help size up would-be riders, to determine whether they’re too fat to fit. If they can’t pull down and lock the seat’s rigid restraint system, they can’t ride.
Park officials say they don’t know how many ill-fitting patrons are turned away, but given that two-thirds of American adults are, by medical definition, overweight or obese (not to mention one-third of American children) the number is probably uncomfortably large.
So places like SeaWorld have had to adapt, as have airlines, which now often require obese travelers to purchase two seats, and ferry operators who have reduced the maximum number of passengers they can safely carry. Even the dead weigh upon the living: Caskets now come in super-sizes; some more than 4 feet wide. And medical schools turn away donor cadavers because they’re too big to store, too heavy to move or the excessive fat simply renders them useless for anatomy lessons.
Most of us know we’re way too heavy and none too healthy. We just don’t like to admit it. According to a 2011 Gallup poll, more than half of American adults think their weight is “about right.” Actual weight versus reported weight is up nearly 20 pounds since 1990. That’s self-delusion on a grand scale.
The debate, though, isn’t about whether we’re fat and getting fatter, it’s why. Answering that question requires a discussion of evolution, human biochemistry, food history and ever-shifting trends in social, political and cultural norms.
In three sentences, it’s this:
- We eat too much.
- We eat badly.
- We don’t get enough exercise.
The average American consumes 2,700 calories per day, 530 more than we ate in 1970. The U.S. Food and Drug Administration recommends 2,000 to 2,500. This is the era of overstuffed. Abnormal is the new normal. In the 1950s, the average soda size was seven ounces. It was the pause that refreshed; not an all-day relationship. Now the average is a big-gulping 42 ounces. Sixty years ago, the average hamburger weighed 3.9 ounces and came with 2.4 ounces of fries. The modern burger plops down at 12 ounces with 6.7 ounces of fries.
We’ve lost all sense of proportion. The U.S. Centers for Disease Control and Prevention says a typical restaurant meal today is now four times larger than it was 50 years ago. Plates are larger, creating an optical illusion that oversized helpings are smaller than they actually are.
“If I had one thing I could teach everyone,” said Marion Nestle, a professor of nutrition, food studies and public health at New York University, “it’s that larger portions have more calories. That turns out not to be intuitively evident and everyone, even me, tends to eat what’s in front of them.”
It’s 7-Eleven 24/7
We are a nation of nibblers and serial snackers. On average, Americans spend 30 minutes a day munching between meals and another 85 minutes quaffing sugary/frothy/caffeinated beverages. It has become way too easy to eat — and to eat poorly.
“The ability to eat so abundantly and so often is a relatively new phenomenon,” said Margaret Schoeninger, a professor of anthropology at the University of California San Diego and co-director of UC San Diego’s Center for Academic Research and Training in Anthropogeny. “Even a generation or so ago, we didn’t eat like we do now, walking, driving, at any time.”
Americans consume 54 billion meals a year at fast-food and table-service restaurants. We typically eat fast food three to four times a week. One in four of us consume fast food every day. Twenty percent of American meals are eaten inside cars.
Most of this food — hamburgers, tacos, fried chicken, pizza and the like — is demonstrably less healthy than fresh food cooked at home. It is high in calories, carbohydrates, fats, sugars and, according to some scientists and nutrition advocates, potentially hazardous chemicals called “obesogens.”
These are substances added to food somewhere along the production line, from farm or factory to kitchen or table. They include fertilizer and pesticide residues, synthetic hormones, pollutants, industrial by-products, preservatives, colorings and other processing compounds.
Added intentionally or not, these chemicals are multitudinous and inescapable. Bisphenol-A, for example, is used in things like food can linings and plastic bottles, where it can leach into food and drink. More than 90 percent of Americans have detectable levels of BPA in their urine. Recent studies suggest BPA – or metabolites of it after the body has broken it down – disrupt normal hormone function. It has been associated with a variety of adverse health effects, including childhood obesity.
“The mice I expose to obesogens in utero get fatter later in life than those that were not exposed, despite the same diet and consumption of the same amount, or even less food” said Bruce Blumberg, a professor of developmental and cell biology and pharmaceutical sciences at UC Irvine who coined the word obesogen. “There is something important going on here that we need to understand.”
This year, the U.S. Food and Drug Administration banned the use of BPA in some food packaging, such as baby bottles, but declined to reverse its official position that the chemical is considered generally safe.
Frankly, the FDA doesn’t really know. It has concerns, and not just about BPA. There are an estimated 80,000 known chemicals on the U.S. market used in consumer products. Thousands of them are used in food processing. Federal regulators have little or no health risk information on the vast majority of them.
No pain, show gain
Steadfast couch potatoes everywhere rejoiced when Danish researchers announced in September that participants in a study who vigorously exercised 60 minutes a day lost less weight than a group of participants who worked out half as hard.
Then came the downer: A third group that was completely sedentary lost no weight at all. “Any amount of exercise is better than none,” study author Mads Rosenkilde told The New York Times.
The CDC recommends at least 150 minutes of “moderate-intensity aerobic activity” per week for every able adult. Children should get at least an hour each day. According to the 2010 Gallup-Healthways Well-Being Index, about half of adult Americans say they get at least 30 minutes of exercise three or more days per week. That’s better than nothing, which is what Gallup says one-third of Americans do.
Obviously, exercise has health benefits more important than burning off excess pounds. It’s linked to every aspect of well-being, including neurological. But there is some evidence that exercise may reduce a person’s tendency to become fat in the first place.
To wit: A 2010 study of 20,000 Britons by researchers at the Medical Research Council Epidemiology Unit in Cambridge that found those who exercised regularly reduced their genetic predisposition to obesity (based on 12 gene variants) by up to 40 percent.
“You don’t have to run marathons to change your genetic makeup,” said study author Ruth Loos. “It is sufficient to do some physical activity, like taking the stairs at lunch or parking farther from the office or mall.”
Fat on the land
In 1990, no state had an obesity rate greater than 14 percent, according to the CDC. Some 20 years later, 36 states have an obesity rate of at least 25 percent; 12 states top 30 percent or more. A study this year by the Trust for America’s Health and Robert Wood Johnson Foundation estimates that if current trends continue, 13 states could have adult obesity rates above 60 percent by 2030; 39 would be above 50 percent and every state would have an adult obesity rate of at least 44 percent.
California has long enjoyed almost mythic status as a haven for sun-bronzed activity and health, but in reality, almost one-quarter of residents are overweight or obese, according to a 2011 study. Susan Babey, a senior research scientist at UCLA who co-authored the study, gives the state kudos for its generally congenial weather — “which means more months out of the year that people can be outside engaging in active pursuits” — and for the state’s tendency to be a leader in novel health policies, such as mandating calorie counts on restaurant menus. But in other ways, we’re just fair to fat-around-the-middling: 26th among states in the percentage of adults who meet physical activity recommendations; 19th in the percentage of adults who are considered inactive or sedentary. Eleven states have lower obesity rates.
All of this body fat is killing us, of course. Obesity is a major risk factor for many high-mortality conditions, most notably diabetes and heart disease. Obesity increases the risk of many types of cancer. It has been linked to autism and memory loss.
The total national health care cost associated with obesity exceeds $147 billion annually. It’s almost $20 billion in California alone, which is enough to pay for 4 million liposuctions at $5,000 apiece.
The vast majority of us, of course, will never have the procedure, but we will have plenty of time to consider it. Despite our growing girth and associated ill effects, the average American life expectancy is longer than ever — about 78 years.
In part, we can thank advances in medicine and treatments for some of our added years. The widespread use of statins, for example, has been associated with dramatically lowering cholesterol levels among the obese, now half of what they were in 1960. And each year, Americans undergo more than 600,000 angioplasties, a procedure used to clear or widen plaque-clogged arteries.
Our children, though, may not live so long. Current mortality forecasts are based on past demographics, says S. Jay Olshansky, a professor in the School of Public Health at the University of Illinois in Chicago and a widely respected authority on aging and life expectancy.
“What they ignore completely is the health status of people alive today,” he said. “Forecasting on the basis of the past is like driving your car by looking in the rear view mirror.”
Olshansky looks at the eating habits and behaviors of people now — particularly the young — and sees a darker, shorter future. “We are already witnessing (obesity’s) harmful effects on health status, such as the rise of fatty liver disease, diabetes, joint problems, et cetera. The lethal consequences will follow.”
Obviously, the vast majority of vast Americans don’t relish carrying extra pounds. We are a nation consumed with restricting what we eat — if only temporarily. We live to diet. At any given moment, an estimated 40 percent of adult American women are on a diet. U.S. weight-loss market revenues exceed $60 billion a year, though research indicates most people diet on their own.
With or without help, most weight-loss efforts fail: Only 5 percent of dieters keep lost pounds off for more than a year. More commonly, Americans look for wiggle room. We buy bigger clothes, for example. The average dress size these days is a 12 or 14, up from a size 8 in 1960. The typical male waistline has increased to almost 40 inches, up five inches from just a generation ago.
But these are, in effect, weighting games. They don’t address the earlier question of why we are fat. For real answers, we require a deeper, more nuanced understanding of the biology and evolution of fat consumption, the myriad “causes” of obesity and its changing list of villains, the socioeconomics of eating and the rise in eating disorders.
Over the next few weeks, every Sunday in the In Depth section, this series will explore these issues and other aspects of the obesity epidemic. Happily, it’s all calorie-free food for thought. You won’t lose any weight reading it — an hour of reclined reading burns a mere 68 calories, less than one-tenth of a Big Mac — but you might gain a few insights.
Scott LaFee, a former science writer for The San Diego Union-Tribune, is a senior public information officer for health sciences research at the University of California San Diego. Email: firstname.lastname@example.org
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