What is Making Us FAT?
Gary S. Gruber, ND

Fat is really not a bad thing unless it is a cause of inflammation and chronic disease. Fat is a source of energy and it is the backbone for making cells and signaling chemicals called hormones.

Here is a shocking statistic: one out of three men and women in the United States are considered overweight. And alarmingly, 17% of children between 2 and 19 years are obese. Every year thousands of people resolve to lose weight, to shed those excess pounds that creep up year by year. Medical experts report that diet and exercise are the key to weight loss. We are bombarded by commercials and programming that suggest diet and exercise are the solution. We buy carefully selected menus and enlist in fitness clubs and programs. Some are successful yet most people shed a few pounds only to rebound to past levels and beyond. The results are miserable and very few people lose weight permanently. People blame themselves for poor lifestyle choices. It is predominant “medical wisdom” that suggests changing behaviors will lead to permanent weight loss.

With a seemly unlimited number of diets and exercise programs, why are the results so poor? “Convincing evidence suggests that diet and activity level are not the only factors in this trend – chemical “obesogens” may alter human metabolism and predispose some people to gain weight.”(1)

Obesogen is a new medical term that combines the two words obesity and estrogen (a hormone in both men and predominately women). Hormones produced naturally in the body are chemical signals that help different systems communicate with each other. Hormones attach to cell receptors like a “lock and key” mechanism that turns on or turns off gene expression. For example, the brain makes a chemical called thyroid stimulating hormone (TSH) that stimulates the thyroid gland to make another chemical thyroxine (T4) that circulates to the liver and kidneys where it is converted to triiodothyronine (T3). T3 is the activated thyroid hormone that stimulates cells in the digestive system, the urinary system, the brain, and other systems to make energy and do work. All along the pathway each thyroid hormone stimulates a cell receptor causing the cell to do something. Hence, obesogens are chemicals that act like cellular signaling hormones that influence weight gain and the inability to lose fat.

The understanding of how obesogens affect cells is still being worked out by scientists and physiologists. The best information so far is based on research concerning tin biocides (“toxic to life”). In this research it was found that these tin-based chemicals stimulated cells by activating a very specific cell receptor, the peroxisome proliferator-activated receptor (PPAR-gamma). (2) Adipose cells are storage depots for fat, a source of energy when food is scarce. In the beginning, when new cells are growing and haven’t quite determined what type of cell they should be, activating the PPAR-gamma receptor of the cell will cause it to become an adipose cell. When an existing adipose cell has its PPAR-gamma receptor stimulated the cell adds more fat into storage.  This mechanism strongly suggests that the environment affects fat metabolism. In a mouse study the researchers gave low doses of perfluorooctanoic acid (PFOA, found in Teflon, Scotchguard, and Gore-Tex) to a group of mice in the same diet of their brothers and sisters who did not receive PFOA. The mice whose diet contained PFOA became morbidly obese. (3)

Obesogens are ubiquitous. They are in our food and water; they are in the air we breathe. Developing children and adolescents are considered more susceptible than adults, but this could be because children born today have a higher total load than their parents and grandparents. (4)

Here are some known and suspected chemicals that are obesogens:  (1)


• Fructose
• Genistein
• Monosodium Glutamate


• Nicotine


• Diethylstilbestrol
• Estradiol

Industrial Chemicals

• Bisphenol A (BPA)
• Organotins
• Perfluorooctanoic Acid (PFOA)
• Phthalates
• Polybrominated Diphenyl Ethers (PBDEs)
• Polychlorinated Biphenyl Ethers (PCBs)

Organophosphate Pesticides

• Chlopyrifos
• Diazinon
• Parathion

Other Environmental Pollutants

• Benzo[a]pyrene
• Fine Particulate Matter (PM2.5)
• Lead

Some of these chemicals like plastics and pesticides are pervasive in our environment. No one can escape them. It is best to minimize exposure by eating organic fresh prepared foods. Avoid cooking with Teflon.   Avoid cans lined with plastic as well as plastic food containers. Drink water that has been filtered through a high quality industrial filter. Avoidance is critical.

Experts agree that all people are carrying a body burden of a majority of these chemicals. While it is very difficult to accurately measure the body burden of these chemicals there is good clinical evidence that supporting and enhancing fat and detoxification metabolism to eliminate these chemicals will result in permanent weight loss.

For information about our Weight Loss and Diabetes Program see: https://sciencemeetsnature.org/services/programs/

Bibliography and Footnotes

  1.     Holtcamp, W. Obesogens: An Environmental Link to Obesity. EHP 120:2 Feb 2012 A63 – A68.
  2.     Evans RM, et al. PPARs and the complex journey to obesity. Nat Med 10(4):355-361 (2004).
  3.     Hines E., et al. Phenotypic dichotomy following developmental exposure to perfluorooctanoic acid (PFOA) in female CD-1 mice: Low doses induce elevated serum leptin and insulin, and overweight in mid-life. Molecular and Cellular Endocrinology 304 (2009) 97 – 105.
  4. Environmental Working Group. Body Burden: The Pollution in People. http://www.ewg.org/sites/bodyburden1.
    See also, Across Generations: Industrial chemicals in mothers and daughters: The Pollution we share and inherit. http://www.ewg.org/reports/generations.


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