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Oct 25, 2024

Your Plastic Water Bottle May Be Making You Gain Weight: Microplastics

Bottled water is up to a hundred times worse than previously thought when it comes to the number of ... [+] tiny plastic bits it contains, a new study in the Proceedings of the National Academy of

Bottled water is up to a hundred times worse than previously thought when it comes to the number of ... [+] tiny plastic bits it contains, a new study in the Proceedings of the National Academy of Sciences said on January 8, 2024.

In our modern world, plastic has become an inescapable part of daily life, from the water bottles we drink from to the packaging of our food. This convenience comes with a hidden and potentially alarming byproduct: microplastics. These tiny particles have been shown in many studies to have infiltrated our environment and bodies in ways we are only beginning to understand. Microplastics are present in everything from the sea salt on our tables to the tap water we drink and even the dust that settles in our homes, according to the National Institutes of Health.

But the implications go beyond mere environmental contamination. Emerging research is revealing that microplastics may be doing more than just polluting our surroundings—they could be affecting our health in profound ways. These particles are increasingly recognized as endocrine disruptors, capable of interfering with our hormonal systems. By mimicking hormones like estrogen and cortisol, microplastics may contribute to weight gain, metabolic issues, fertility and other serious health problems. As scientists continue to uncover the pervasive presence of microplastics, it’s becoming clear that our reliance on plastic is not just an environmental challenge, but a pressing public health concern.

Microplastics are everywhere. These are tiny particles less than 5 millimeters in diameter, with nanoplastics typically being less than 1 micrometer in size. Primary microplastics enter the environment already less than 5 millimeters in size, including microfibers and microbeads. Secondary microplastics arise from the breakdown of plastics. They commonly result from floating waste in our oceans that is continuously exposed to UV radiation, causing them to degrade and enter our food chain.

They are also in the products we use daily. Every liter of bottled water contains at least 240,000 microplastic particles. They’re not just in plastic bottles and containers. They also arise from plastic cutting boards, Teflon cookware, fabrics and beauty products. The implications of their presence in our lives are alarming. Emerging research suggests that these microplastics may significantly impact our health, acting as endocrine disruptors, altering hormonal signaling and potentially leading to weight gain and other serious health issues.

(If you want to learn more about the best medical treatments to help you lose weight, read my previous article Ozempic and Weight-Loss Procedures: Benefits, Costs And Risks)

Plastic pieces in frozen water. Despite decades of effort, plastic pollution is only getting worse.

Microplastics can act like xenoestrogens, chemicals that mimic estrogen by binding to estrogen receptors in the body. This can disrupt the hormonal balance, particularly in children, leading to early puberty and unusual weight gain. The disruption of natural hormone functions is a growing concern, especially as we observe more children experiencing these health issues at younger ages. This can also have negative effects in adult males, including weight gain, erectile dysfunction, gynecomastia, reduced sex drive, decreased energy, decreased muscle mass and infertility, according to a study published in 2021 by researchers at the University of Naples Parthenope in Italy.

A pregnant woman at the office.

The impact on fertility is less commonly discussed. Research suggests that exposure to endocrine-disrupting chemicals, including microplastics, may decrease sperm count, reduce sperm quality and negatively impact testicular weight. There is also animal evidence for uterine and ovarian involvement. Microplastics have also been identified in human placental tissue and meconium demonstrating fetal exposure, according to a 2022 study published in the International Journal of Environmental Research and Public Health. This is all rather concerning in light of the declining fertility rates seen in developed nations.

Beyond mimicking estrogen, microplastics can also influence cortisol levels. Cortisol is often referred to as the "stress hormone." High levels of cortisol are associated with weight gain, especially around the abdomen, and can lead to other health issues like anxiety and insulin resistance. Microplastics can mimic cortisol, disrupting our endocrine system and leading to a cascade of negative health effects. This pseudo-cortisol effect can add to chronic stress, and is linked to increased fat storage and other metabolic issues. It’s a vicious cycle: stress leads to higher cortisol levels, which leads to weight gain and other health problems including reduced vascular elasticity and hypertension.

As a Harvard Medical School physician specializing in weight loss, a researcher in the study of obesity and metabolic disease and the pioneer of several non-surgical weight loss interventions, including the Endoscopic Sleeve Gastroplasty stomach tightening procedure, I have spent my career helping patients to tackle obesity through science and medical treatment. The studies are clear. Once that weight is gained, for some people, it’s very difficult to take it off again.

As I wrote in a previous article, “Obesity Is A Disease. It’s Time We Treat It Like One,” genetic and physiological factors are huge contributors to obesity. For those people, the addition of high cortisol levels could make it extremely difficult to lose excess weight. High cortisol can contribute to a dysregulated appetite by influencing hunger hormones like ghrelin and leptin. When some people gain weight, their metabolic rate adjusts, creating a new set point at the higher weight. This phenomenon, known as the set point theory, suggests that the body actively works to maintain this new weight, making weight loss challenging. These metabolic changes can reduce the number of calories burned at rest and increase feelings of hunger, making it harder to control appetite and lose weight through conventional diet and exercise. It’s not your imagination; your body can be working against you.

(If you want to learn more about the best medical treatments to help you lose weight, read my previous article Ozempic and Weight-Loss Procedures: Benefits, Costs And Risks)

Food taken out from a microwave oven

The primary sources of microplastic exposure are ubiquitous in our daily lives. Drinking from plastic water bottles and microwaving food in plastic containers are two of the most significant ways these particles enter our bodies. When plastic is heated, it releases microplastics and other chemicals into the food or drink it contains, which we then ingest.

Microplastics are not just in bottles and containers—they’re in our beauty products, fabrics and even the air we breathe. Parabens and phthalates in shampoos and cosmetics, Teflon in cookware and synthetic fibers in clothing all contribute to our daily intake of microplastics.

Stainless steel water bottle

While the research continues to evolve, there are steps we can take to reduce our exposure to microplastics:

Microplastics are a significant health threat that we are only beginning to understand. Their ability to mimic hormones and disrupt our endocrine system can lead to weight gain, early puberty in children, fertility issues and a host of other health problems. By taking steps to reduce our exposure to these harmful particles, we can protect our health and well-being. It’s time to rethink our reliance on plastic and make conscious choices for a healthier future.