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Is Your Shampoo Making You Fat?

That roll around your midsection could be due to more than just fatty foods and lack of exercise.
A growing body of research links our expanding waistlines to the toxic ingredients in products we use every day, from cosmetics to baby bottles

We all know that Americans -- leading the way for the rest of the developed world -- are getting fatter. We hear about the "obesity epidemic" on the TV news, with footage of people depicted from the waist down shuffling around in XXL sweat pants and carrying super-sized sodas. The majority of us are overweight, complaining about how our jeans are getting tighter and wondering why, despite all our efforts to diet and go to the gym, the number on the scale keeps edging higher.

For years, the explanation for weight gain was straightforward: it was all about energy balance, or calories-in versus calories-out. This Gluttony and Sloth theory held that obesity simply came from over-eating and under-exercising, and the only debate was about dieting -- whether it was better to join the low-fat or the low-carb camp. Some scientists explored genetic differences associated with fat, but others said genes couldn’t possibly explain the rate at which Americans were gaining weight: "We just aren’t evolving that fast," one obesity expert noted.

Environmental scientists have long suggested that there were likely external factors at work, but until recently, the traditional obesity-research community rejected such claims. Now it seems that the tide is turning: This month’s issue of Obesity Reviews features an extensive look at the accumulating body of research linking the environment with obesity.

The idea of our surroundings contributing to weight gain is nothing new, of course. But past discussions about the role of the "environment" focused mostly on the fast-food culture that we live in, where highly-processed, highly-caloric foods are constantly available, eating times are chaotic, kids run around drinking sugar-saturated sodas all day, no one has time to cook, fruits and vegetables are scarce in low-income urban areas, a venti frappuccino has 760 calories, and muffins are the size of melons. Add to that our changing physical environment -- the fact that everyone sits in front of computers every day, instead of working out or working on the farm -- and the "calories in" excess of the weight equation seems obvious, and obesity over-determined.

But even allowing for such influences, something wasn’t adding up. There are plenty of people out there who eat well and exercise like Gwyneth Paltrow and still feel like their weight is out of control. Then there are those annoying people who eat everything they desire, never work out, and stay thin. There had to be more to it than calories. We know that hormones -- the chemical messengers produced by our endocrine system to control things like blood pressure and insulin production -- can fatten up animals for slaughter; that some drugs increase your weight; and that a change in hormones at midlife shifts where your fat is distributed. Researchers began to recognize that obesity is much more complicated than calories in and out, and that a lot of other mechanisms involving the hormonal regulatory system are involved in our bodies’ delicate weight balance.

Paula Baillie-Hamilton, an expert on metabolism and environmental toxins at Stirling University in Scotland, was among the first to make the link between the obesity epidemic and the increase in the chemicals in our lives. "Overlooked in the obesity debate," she wrote in 2002 in the Journal of Alternative and Complementary Medicine, "is that the earth’s environment has changed significantly during the last few decades because of the exponential production and usage of synthetic organic and inorganic chemicals."

Exposure to those chemicals, said Baillie-Hamilton, can damage the body’s natural weight-control mechanisms. She calls toxic chemicals that act as endocrine disruptors -- mimicking hormones, and blocking or exaggerating our natural hormonal responses -- "chemical calories," and those in question include Bisphenol A, phthalates, PCBs, persistant organic pollutants such as DDE, a breakdown product of the insecticide DDT, and pesticides containing tin compounds called organotins. Many studies have shown that endocrine disruptors have been linked to early puberty, impaired immune function, different types of cancer, birth deformities, and other diseases. Now obesity and metabolism are on that list.

NRDC: Regulating Obesogens

Sarah Janssen

Q&A with Sarah Janssen, senior scientist with NRDC’s health program in San Francisco.

Studies have associated exposure to phthalates and Bisphenol A (BPA) with adverse health affects, including changes in metabolism and in fat distribution in the body. Why has the FDA failed to regulate the use of these substances in food packaging?

Both BPA and phthalates were approved for food packaging use in the 1960s. Back then, the FDA and the scientific community weren’t aware that chemicals could interfere with hormones and lead to infertility, cancer, or metabolic changes. Because the FDA is not required to routinely re-evaluate the toxicity of food additives, these chemicals continue to be used in food packaging. But the FDA does have the power to revoke approval of a food additive when it is not shown to be safe. FDA has re-evaluated BPA toxicity after a public outcry, but it has delayed regulating it while it conducts further research.

Read the rest here.

Environmental researchers call these chemical calories "obesogens." Bruce Blumberg, a University of California at Irvine Professor of Developmental and Cell Biology, studies the effects of endocrine disruptors on obesity in mice and sees clear differences between those who are exposed to them and those who aren’t. "Pretty much anyone who observes people knows that obesity is way more than eating and exercise," says Blumberg. Instead, metabolism, appetite, and the number and size of fat cells you have come into play, all of which are affected by hormones, and therefore by hormone disruptors. Blumberg has shown that the organic pollutants tributyltin and triphenyltin derail the hormonal mechanisms that control the weight of mice. He’s found that when pregnant mice are fed a dose of organotins that is equivalent to normal human exposure to those chemicals, their offspring have 10 percent more fat cells than normal mice, the fat cells grow bigger than normal, and they end up, overall, 10 percent fatter than your average mouse.

Other compelling research that fat is not just about eating and exercise comes from studies that show that animals that live in human environments get fatter just by virtue of being around people. Researchers at the University of Alabama recently found that chimpanzees, macaques, mice, rats, dogs, cats, and other species that lived in proximity to humans got fatter than animals that didn’t live in an industrialized environment -- even when their lab chow and exercise was highly controlled. The authors suggested that endocrine disruptors were one likely culprit in this cross-species obesity epidemic.

For her article in the new Obesity Reviews, Jeanett Tang-Peronard, of the Institute of Preventive Medicine in Copenhagen, looked at some 450 studies on endocrine disruptors and obesity and found that nearly all of them showed a correlation between exposure to those chemicals -- particularly in utero and in early childhood, when hormonal mechanisms are vulnerable -- and an increase in body size. She says that in early life, chemicals seem to alter the epigenetic regulation of certain genes, disrupting the programming of hormonal signaling pathways that affect fat storage, fat distribution, and appetite. (The epigenome governs patterns of gene expression.) This reprogramming could explain how we are indeed evolving so fast.

Tang-Peronard says that it is impossible, now, to tease out how much of obesity is caused by chemicals, and how much by energy balance. They’re intertwined, anyway, with imbalances in appetite-regulating hormones like leptin and ghrelin causing us to want to eat more of the available food. "Endocrine disruptors may play a significant role in obesity," she says. But the research is in its infancy. She also points out that only a few of the tens of thousands of known environmental chemicals have been tested for their association with obesity. "We are only scratching the surface," she says.

What to do about the problem of endocrine disruptors and obesity? It’s hard to say, given that virtually all humans have been exposed. Pediatrician Maida Galvez is involved in the Mt. Sinai "Growing Up Healthy" study of 330 children in East Harlem, monitoring their exposure to endocrine disruptors and their body weight. "Even if these chemicals play a small role in obesity, it’s a preventable exposure," she says, explaining that if certain substances can be determined to have deleterious effects, we can avoid them at critical stages of development and ultimately replace them with safer alternatives.

For now, Galvez recommends that parents steer clear of Bisphenol-A -- present in many plastic water and baby bottles, and in microwavable and dishwasher-safe food containers. (If you find a printed "7" on the bottom, get rid of it.) She also suggests avoiding shampoos, cosmetics, and soaps containing phthalates -- up to 70 percent of "top-selling products," according to a 2002 report by the Environmental Working Group. (Look for fragrance-free products, which are less likely to contain phthalates, or for anything from the Illumina Organics range or The Body Shop.) And, she says, eat fresh fruits and vegetables, instead of foods that are processed and/or packaged in plastic.

That’s one point on which traditional obesity researchers and environmental scientists agree: Eat plenty of fresh, organic vegetables. And while you’re at it, get out into the fresh air and get some exercise.

image of Laura Fraser
Laura Fraser is the author of "Losing It: America’s Obsession with Weight and the Industry that Feeds On It" and the recent travel memoir "All Over the Map". The San Francisco-based journalist has written for the New York Times, Tricycle, Gourmet, ... READ MORE >
Another reason to pass the Safe Cosmetics Act!
another reason for those who are obese to think it's not their fault. If you are obese, turn to diet and exercise, not an "earth friendly" shampoo. I have used cheap shampoo for years, and remain the same size. News flash: those rolls of fat? They only leave when you actually lift your bum up and do something about it.
I think they're suggesting a comprehensive understanding of how everything around us can affect our bodies and health. Everybody wants a simple, single cause for problems, and the article says that probably isn't the case. That said, you're right - get some exercise before trying to blame your shampoo.
Surprised you were open minded enough to read anything from the NRDC or even environmental! Who are you to say what does what until you furnish your phd. You are allowed to have your opinion, but really, who are you to say why someone if fat and what they need to do to get better or that got them that way. I gained weight when I had my kids. It's not gone 2 yrs later. I have done what I am supposed to do. I worked out for 1.5 hours a day through 2 pregnancies, I nursed a year each for both kid. I still gained weight. I have 1500 calories a day and I work out with or without the kids. Why don't you tell me what's wrong with my fat rolls now?
Fat cells can't grow without your body taking in excess calories. They are not magic and are not fed by chemicals. Only excess calories in can create increased body mass. Period. The amount of calories it takes to be "excess" may be influenced by other things as this article discusses and it's probably a good idea to limit your exposure to unnecessary, over-processed, and highly-marketed items. It's hard to limit yourself to 1500 calories a day, but if you still have excess fat you still are taking in more calories than you body needs. There's no way your body can produce mass without calories. I'm sorry, but there just isn't.
Eat healthy. I see no indication that you are already doing so, based on your comment.
Persons that are bald and overweight?????????
Anonymous User #1, why don't you get some compassion--and perhaps a basic understanding of the fact that your experience isn't universal--before you decide you've got everyone else's problems figured out.
To this I would add that it would have been really nice if Anonymous User #1 could have bothered to read the article. A closed mind is the most flagrantly ignorant.
It would be nice to have a list of products that don't have those chemicals to give us something to do about it...
read the bottles.
It is easier to find a company that promises not to use these harmful or hormone altering ingredients. I use one Arbonne. That I get my shampoo, conditioner, lotion, makeup to fiber and protein from. They have been in business for over 30 years, have great products, and are reasonable. You have to go through a consultant though and I know of one (you can e-mail me @ and I'd be happy to pass along the information). Other good companies for household cleaners are,, and vinegar works great for cleaning (don't use on granite it will cause a chemical reaction and fog it up). For Pesticides and Lawn Care there is Hope thats helps!
I stopped using shampoo about a year ago. The products that I use are baking soda in a small plastic container (not BPA #7) and then another small bottle with cider vinegar plus some fragrant and essential oils, like peppermint oil, vanilla, and tea tree oil. I mix the baking soda with the water from the shower head and make a dilute paste that serves as shampoo. My hair gets squeaky clean this way. Then I shake a few ounces from the vinegar bottle into my hair which serves as a conditioner. Rinse and I'm done! I often wonder how primitive humans cleaned their hair before we had aisles and aisles of bottled toxins to clean our hair with.
For those of you looking for safer body care alterntives check here: For a quick basic list of chemicals to avoid (although I try to avoid as many chemicals / synthetics as possible), check here: For further info on ingredients, check here: ♥ I'm a 33 year old Breast Cancer Survivor trying to lessen the toxic overload on my body without lowering my standards. ♥ NOT Your Typical Tree-Hugger! ♥ Truly Natural & Organic Beauty Blog ♥ Ghetto-Fabulous $ Saving Tips ♥ Most Product Reviews Score LOW on The Skin Deep Cosmetic Safety Database
"We know that hormones --- the chemical messengers produced by our endocrine system to control things like (sic) blood pressure and insulin production ---- can fatten up animals for slaughter". This is just the type of statement that someone in denial of the 'bottom line' cause for obesity will ignore in favor of more calories that will cause them to "fatten up". There is no doubt that other factors, including chemical factors introduced by elements of daily use may have some affect including adverse ones on our bodies but one must be VERY careful in the verbage used to describe the possible effects. There are many obese individuals who are in denial of the concept of caloric intake causing their weight gain and hunt for any support for their position. They need our help (knowledge and understanding) not another reason to stay in their unhealthy habits.
How to Beat the Fat-Trap DesteniHealthCare >>
I think its a culmination of things. I believe food has alot to do with it. What they put in chicken, milk and everything else. I remember years ago they started putting a growth hormone in milk cows feed. Places would advertise they werent doing it. If you look closely, kids are bigger now, young girls are growing larger breasts earlier and other things are going on. Something isnt kosher.
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Be aware. get to know your being, its sensitivity. notice your emotional responses to yourself , the world Pay attention to your neural network, it knows, get honest with yourself and life. These chemicals subtly effect emotional responses. if your sensitive , get them out of your life, they plastic coat the beautie you believe you don't have. Those that would be deceivers have need to hide their smell and smell like a petroleum plant anyway.
This makes zero sense. It's just another sensationalist exploitation of peoples' fear of chemicals and science. There is one simple observation that debunks the entire premise: if 'chemicals' make us fat, why isn't everyone fat? I am no nature-freak. I have used Pantene shampoo and bought my meat at Safeway since I was a kid, and I was skinny all my life. I gained weight when I crossed the 30-year-line and kept eating Cinnabons and ice cream every day. Working out and controlling my diet got me back to my old skinny self. Everyone I see at the gym loses weight or maintains a healthy body; everyone I see who is obese refuses to do any physical exercise. Take responsibility for your own life. Nobody is forcing you to be skinny - if being fat makes you happy, good on you. But you are what you make of yourself.
Wasn't DDT banned in the 60's? This is nonsense.
While DDT may not be used in the USA it is used in other countries. Do you know where everything you use comes from? I think that is something we all should consider.
Well, now that Global Warming has jumped the shark the Greens are going to need something to enable their liberal fascist tendencies. Behold, chemicals make you fat! This one just might work...
Tang-Peronard says that it is impossible, now, to tease out how much of obesity is caused by chemicals, and how much by energy balance. They’re intertwined, anyway, with imbalances in appetite-regulating hormones like leptin and ghrelin causing us to want to eat more of the available food. "Endocrine disruptors may play a significant role in obesity," she says. But the research is in its infancy. She also points out that only a few of the tens of thousands of known environmental chemicals have been tested for their association with obesity. "We are only scratching the surface," she says.
Excellent reasons to quit sensationalizing this junk science.
The article seems to imply that these chemicals can make you fat - no matter how much you eat or exercise. It is *still* a simple matter of calories in and calories out. No matter how much chemicals screw with your hormones, if you don't have excess calories to store, you won't put on wieght (as fat). They may mess up your metabolism such that it is *harder* to burn calories, or so that your body will metabolise different foods improperly - but they can't add fat if the baody doesn't have the calories to do so.
Or it could be the estrogens in the drinking water. While supposedly most from birth control pills are screened out, women routinely put in weight on the pill...
This can seem overwhelming, yet it is such an important issue that it is worth doing you best to avoid synthetic chemicals. Ultimately, it is wise to eat as natural as possible, avoiding food in plastic with long lists of ingredients. Aim to use as natural as possible skin care (becoming an ingredient detective is key learn what is safe & what isn't) and remember you can only do your best! In the last 80 years synthetic chemicals have crept into our food, personal care products and homes. Baking soda and vinegar can clean the house just as well as expensive potions in spray bottles, and it is wonderfully cheap.