It's not just about calories in versus calories out.
If that were all it took to lose weight—eating a little less and exercising a little more—then weight loss would be as simple as grade-school math: Subtract Y from Z and end up with X.
But if you've ever followed a diet program and achieved less than your desired result, you probably came away feeling frustrated, depressed, and maybe a bit guilty. What did I do wrong?
Instead of X, it's XXL.
Because there's probably more at work here than just calories in/calories out. More and more research is indicating that America's obesity crisis can't be blamed entirely on too much fast food and too little exercise. A third factor may be in play: a class of natural and synthetic chemicals known as endocrine-disrupting chemicals (EDCs), or, as researchers have begun to call them, obesogens.
The New Weight-Gain Threat
Obesogens are chemicals that disrupt the function of hormonal systems; many researchers believe they lead to weight gain and, in turn, numerous diseases that curse the American populace. They enter our bodies from a variety of sources—natural hormones found in soy products, hormones administered to animals, plastics in some food and drink packaging, ingredients added to processed foods, and pesticides sprayed on produce. They act in a variety of ways: by mimicking human hormones such as estrogen, by misprogramming stem cells to become fat cells, and, researchers think, by altering the function of genes.
Endocrine disruptors are suspected of playing a role in fertility problems, genital malformation, reduced male birth rates, precocious puberty, miscarriage, behavior problems, brain abnormalities, impaired immune function, various cancers, and cardiovascular disease. "We have data linking environmental chemicals to practically every major human disease, from cardiovascular disease to attention-deficit disorder," says Jerry Heindel, Ph.D., an expert on EDCs at the National Institute of Environmental Health Sciences (NIEHS).
Now new research is finding that some EDCs, the obesogens, may be helping to make us fat. This field of research is dominated by animal and test-tube studies. And while researchers note that the known effects of many obesogens are more potent in the unborn and newly born, some suspect a similar impact on adults.
This combination of factors, along with our growing tendency to put on weight, is what we call the obesogen effect. Understanding it could be the key to freeing ourselves from weight gain and the other hazards of these chemicals.
Why Traditional Diets Don’t Work
Decades ago, before big, soft guts were the norm in the United States, we referred to overweight people as having "glandular problems." Their weight was not their fault, doctors explained; their bodies just didn't have the ability to fight off weight gain like most people's bodies did.
We don't use that polite phrase any longer. What changed? Now that about two-thirds of American adults are overweight or obese, did those folks with "glandular problems" disappear? No; it's just that many others have caught the same disease. Thanks to the obesogen effect, we may all be at risk for some glandular problems.
Because it's probably been a while since you took high-school anatomy, here's a quick refresher: Your endocrine system is the contingent of glands producing the hormones that regulate your body. Growth and development, sexual function, reproductive processes, mood, sleep, hunger, stress, metabolism—they're all controlled by hormones. And the pancreas, hypothalamus, adrenal glands, thyroid, pituitary gland, and testes are all part of that system. So whether you're male or female, tall or short, hirsute or hairless, adminlean or heavy—that's all determined in a big way by your endocrine system.
Your endocrine system is a finely tuned instrument that can easily be thrown out of kilter. "Obesogens are thought to act by hijacking the regulatory systems that control body weight," says Frederick vom Saal, Ph.D., curators' professor of biological sciences at the University of Missouri. "And any chemical that interferes with body weight is an endocrine disruptor."
That's why obesogens seem to be good at making us fat—and why researchers are so bent on uncovering the truth about these chemicals. The NIEHS is funding studies that target them. The Endocrine Society, the largest organization for hormone research and clinical endocrinology, has also noted the connection. "The rise in the incidence in obesity matches the rise in the use and distribution of industrial chemicals that may be playing a role in generation of obesity," it stated in a recent report, "suggesting that EDCs may be linked to this epidemic."
That's one reason why weight-loss advice may not always work. In fact, even strictly following the smartest traditional advice won't lower your obesogen exposure. See, an apple a day may have kept the doctor away 150 years ago. But if that apple now comes with chemicals believed to promote obesity, then that advice is way out of date. In fact, apples have been named one of the most pesticide-laden produce choices out there.
Hormones, Chemicals, and Weight Gain
The New American Diet
It's not just about calories in versus calories out.