As researchers continue to probe the possible causes of America s ongoing obesity epidemic, Barry Popkin, a professor of nutrition at the University of North Carolina, Chapel Hill, says his latest research demonstrates that people are eating more now by about an extra 600 calories per day than they did in the 1970s. After analyzing data from dietary surveys, Popkin found that Americans were consuming an average of 1,800 kcal between 1977 and 1978, but that number escalated to almost 2,400 between 2003 and 2006. Researchers found that larger portion sizes and more frequent eating during the day are to blame for our nation s expanding waistlines over the last 30 years.
In addition, we eat more and do less, says Dr. David Katz, director of the Yale University Prevention Research Center. This is because healthy exercise has been increasingly displaced by joysticks and keyboards, adds ACSH's Dr. Gilbert Ross.
Our eating habits have also changed in the last few decades, according to Dr. Keith Ayoob, director of the Rose R. Kennedy Center Nutrition Clinic at Albert Einstein College in New York City. He notes that the pace of many people s lifestyles means that we re no longer eating at a table with a knife and fork, and instead, we want a breakfast you can hold in one hand.
ACSH s Cheryl Martin agrees with this notion. Drawing upon her experiences growing up, she remembers when going to get a meal at White Castle was considered a treat, not a regular occurrence. How ever often kids and even grown-ups eat at fast food restaurants, the bottom line is that it s not the restaurants responsibility but our personal responsibility to be aware of how much we consume and how much our kids consume on a daily basis. Let s not mix up access with excess and also, let s not forget the need to exercise regularly.
However, it may be more than just extra calories that is making us fatter a lack of good-quality sleep may also be contributing to the obesity epidemic. Americans are now averaging 6.5 to 7 hours of sleep each night, which is much less than the 8.5 hours they were getting in 1960. Researchers say that restricted sleep may lead to weight gain because of changes in certain hormone levels. One study found that the average level of leptin a hormone that controls feelings of fullness decreases by 18 percent when sleep is restricted to four hours per night over two nights. In the same study, the level of ghrelin a hormone that triggers hunger increased by 28 percent.
Or, muses ACSH's Dr. Josh Bloom, it could be as simple as being awake more hours gives you more time to eat.
Sleep deprivation is not unique to adults, however. A study of over 8,000 kids starting at the age of about 10 months found that, by the time they reached the age of seven, the odds of being obese increased by 50 percent among children averaging less than 10.5 hours of sleep.
Though poor sleeping patterns and larger portion sizes may be plausible explanations for the rise in obesity, increased use of personal hygiene products such as shampoo surely is not. That, however, hasn t stopped Laura Fraser from writing a misleading article for OnEarth, featured in Grist, that blames so-called endocrine disrupting chemicals, including Bisphenol A (BPA), phthalates, PCBs, and organotins (pesticides containing tin compounds), for excess weight gain. Even though she labels them chemical calories and obesogens, Fraser acknowledges that it s impossible to determine how much of obesity is actually caused by chemicals. Well, Dr. Ross can answer that question fairly easily: None. Unlike shampoos, what we eat and how often, plus how much energy we expend, are the keys to obesity not chemicals that have been safely in use for over 50 years.
Dr. Bloom adds, Shampoo consists mostly of soap, which does have a good number of calories if you drink it. I wonder how much of the stuff Ms. Fraser puts away when no one s watching?
