Obesogens: chemicals that make you put on weight

In this Article (Index)

• The Obesity Pandemic
• Environmental factors behind obesity
• Endocrine-disrupting chemical (EDC)
• The Obesogen Hypothesis
• How do obesogens make you obese?
• The "Developmental Origins of Health and Disease" (DOHaD) model
• You can inherit your obesity!
• List of some Verified Obesogens
• Taking action against Obesogens

The Obesity Pandemic

Obesity has tripled globally over the past 50 years. Now over 650 million people are obese (8% of the world's population, almost 1 out of every 12 human beings). In the United States nearly 40% of adults over 20 (more than 93 million people), up from 30% in 2000.
Another 18% of those aged 2 to 19 (41 million) are obese, up from 14% in 2000. (8)

The common explanation for this rise in obesity is that people are less physically active and eat calorie-dense processed foods. But this model isn't sufficient to account for the scale of global obesity, other environmental factors play a role in it.

Obesity is a risk factor for many diseases like type-2 diabetes, cardiovascular diseases, and cancer. Obesity also affects life quality and mental health.

Environmental factors behind obesity

Altered gut microbiomes, disrupted circadian rhythms, stress, air pollution, and chemicals like endocrine-disrupting chemicals (EDCs) are all linked to obesity. (3)

Endocrine-disrupting chemical (EDC)

EDCs are natural or man-made chemicals that interfere with, block, or mimic the body's hormones. You come in contact with them by contact with your skin, inhalation, or by their presence in foods. EDCs are associated with obesity in humans and cause obesity in laboratory animals.

Research has found many negative consequences of EDCs such as ADHD-related behaviors in adolescence, lower immune responses, premature births, premature breast development in girls, and abnormal breast development in boys, early-life exposure to EDCs has been associated with later-life diabetes and cancer.
EDCs also provoke epigenetic changes that alter how genes are turned on and off, causing genetic changes that could be transmitted by EDC-tainted parents to their unexposed offspring, leading to intergenerational toxicity. (9),(10)

The Obesogen Hypothesis

The obesogen hypothesis holds that there are chemical products (including EDCs) that increase the risk of becoming overweight in susceptible people. By inhaling, ingesting, or through skin contact with these chemical compounds people could become obese (6),(3)

The term "obesogen" was coined in 2006 and it combines the prefix "obese" and the suffix "-ogen", from the Greek word "genea" = to produce, related to "genesis".

Like EDCs, they alter the body's biochemical balance, and animal studies have shown that they can increase the number of white adipose tissue (WAT), increase the storage of fat in these fat cells (adipocytes), and also generate dysfunctional adipocytes. These animal studies have been corroborated by epidemiological studies and other trials.
Around 50 chemical compounds have been classified as obesogens.

These chemicals are found in plastics used in packaging, bottles, cookware, furniture, coatings, building materials, food additives, cosmetics, herbicides, fungicides, pharmaceuticals, industrial manufacturing processes, and children's toys. (1), (7)

How do obesogens make you obese?

These chemicals alter eating behavior by disrupting appetite control, the diversity and composition of the gut microbiome, and metabolism. They also affect how much energy is stored as fat. (3)

The effects of obesogens (most of which are EDCs) "could be potentiated by the presence of a high-fat diet or a mix of different types of EDC. In conclusion, EDC induces obesogenic effects." (7)

The "Developmental Origins of Health and Disease" (DOHaD) model

The DOHaD model explains how adult physiology is not only shaped by intrauterine development during pregnancy. Instead, it holds that poor nutrition, stress, exposure to pollution, EDCs, and obesogens during a child's early life can cause their bodies and metabolism to change permanently and influence their susceptibility to disease and poor health during their adult life.

These changes alter their hormones and disrupt appetite, growth, and the formation of fatty tissue leading to a higher risk of obesity. Obesogens have acted upon your body since you were a child. (3),(2)

You can inherit your obesity!

Animal studies have shown that phthalates and tributyltin (TBT) can cause obesity across three or more generations. Transgenerational inheritance of obesity is serious because it affects people who were never exposed to obesogens in the first place.

Obesogens cause changes in the DNA, known as epigenetic changes which become permanent and are passed on to the next generation. These epigenetic changes are irreversible. (6)

List of some Verified Obesogens

Below is a list of some verified obesogens with their uses and effects. It includes phthalates, flame retardants, food additives, and pesticides, among other chemicals.

• 3-BHA. Food additive (antioxidant)^✻
• Carboxymethylcellulose.. Food additive (thickener, emulsifier)^✻
• Monosodium glutamate (MSG). Food additive (flavor enhancer)^✻
• Span-80. Food additive (surfactant)^✻
• P-80. Food additive (emulsifier)^✻
• Parabens. Preservatives (pharma, cosmetics, and food industry)^❆
• Dioctyl sodium sulfosuccinate (DOSS). Food additive (emulsifier)^✻
• Bisphenols - Bisphenol A, F, and S. Plasticizer (plastics)^&❆
• DEHP or di-2-ethylhexyl. Phthalates. Plasticizer (plastics)^❆
• Mono-2-ethylhexyl (MEHP). Phthalates. Plasticizer (plastics)^❆
• Perfluoroalkyl and polyfluoroalkyl substances (PFAS). Anti-stick coating. (food packaging and cookware)^❆
• Dibutyltin (DBT). Organotin (paper, plastics, paints)^✻
• Tributyltin (TBT). Organotin (plastics, slime control in water, pesticides)^✻
• Triphenyltin. Organotin (slime control in water, pesticides)^✻
• Glyphosate. Pesticide (herbicide), also linked to prostate cancer,^✻
• Imidacloprid. Pesticide (insecticide)^✻
• Triflumizole. Pesticide (fungicide)^✻
• Flame retardants; PBDEs and OPFRs. (furniture and consumer electricals)^❆
• Polychlorinated biphenyls - PCBs. (used in past industrial processes, pervasive in the environment)^❆
• Nonylphenol, microbial decomposition product of a surfactant nonylphenol ethoxylates^✻
• Acrylamide. Produced during baking, roasting, and frying. Learn about acrylamide and its risks^✻
• Fine particulate matter. Air pollutant particles^❆
• Cadmium. Heavy metal (contaminated food, water, and air)^❈
• Arsenic. Heavy metal (contaminated food, water, and air)^❖

Sources: ^✻(3); ^❈(4); ^❖(5); ^❆(7)

Disruptive effects of obesogens

Some examples of the effects of these obesogens: both carboxylmethylcellulose, which are used as food emulsifiers disrupted the microbes that live in the gut and produced intestinal inflammation which led to weight gain, increased white adipose tissue and metabolic syndrome in mice. Another food additive, 3-BHA used to keep fats and oils from going rancid, also made bice fatter and with higher lipid levels in their blood. Monosodium glutamate (MSG), a flavor enhancer provokes obesity in mice.

Taking action against Obesogens

What can be done? Is there a solution? There are three courses of action to reduce the negative impact of these chemicals:

1. Individual Action

As individuals, we can take a hands-on attitude and use less plastics, recycle more, and be conscientious in our purchases avoiding products that could harm us (like french fries and acrylamides, anti-stick cookware, etc.)
We can also take part in campaigns to raise public awareness and support politicians who promote legislation to protect us from obesogens and EDCs.

We can try to eliminate other obesity-promoting factors by modifying unhealthy lifestyles: avoid smoking, alcohol, and ultra-processed foods, and try to include more physical activity in our daily lives.

But, as individuals, it is hard to avoid these pervasive chemicals in our foods, cosmetics, water, and homes, or alter the genetic changes they caused in our ancestors.

2. Medicine and Science

Researchers should work towards treatments to counter the effects of obesogens and EDCs, learn more about individual susceptibility, review more potential EDCs and obesogens, and revise the existing ones to provide data for the authorities to regulate exposure.

3. Regulation

The government should review the tolerable daily intake values of known EDCs and obesogens as a way to lower their negative effect. For instance, the tolerable daily intake for Bisphenol A (BPA) had been set by the European Food Safety Authority (EFSA) at 4 micrograms (μg) per kilogram (kg) of body weight. But, after revising the risk and effects of BPA, the EFSA has proposed to lower this by 100,000-fold and restrict its use.(6)

Obesogens should be classified separately from endocrine disrupters as substances of great concern, those shown to be harmful should be banned, and public awareness campaigns should be set up for instance through product labeling. (6)

Future research should focus on defining safe exposure levels and learn more about child exposure effects. (6)

The industry should have more stringent evaluations for new chemical compounds and nations should support global policies to regulate pollution and promote sustainability. (1)