Microplastics are everywhere — here’s what that means for your health

The visuals, from studies and experts, are almost too wild to be believed: That we have the equivalent of an entire plastic spoon in our brains. That we eat about a credit card’s worth of plastic per week. That in a year, we consume the equivalent of up to 50 plastic bags.

If right about now you’re thinking that you have never munched on a to-go bag ever, that’s not where this plastic is coming from. It’s the result of something hidden in our food and beverages: micro- and nanoplastics. Here’s what you need to know about these microscopic pieces of plastic, how they get into your body in the first place, their health effects, and practical tips for cutting down on them in your life.

What are microplastics?

Microplastics are very small pieces of plastic that you regularly come in contact with — but probably don’t even realize it. That’s because they’re invisible to the naked eye. Microplastics are less than five millimeters in size, while nanoplastics are less than one micron. (For perspective, a human hair has a diameter of 70 microns.)

But just because you can’t see them doesn’t mean they aren’t there. In fact, micro- and nanoplastics are pretty much everywhere. “Some plastics are deliberately used in products like paint or cosmetics, but the majority of them come from the degradation of plastics, especially single-use plastics like water bottles and containers, as well as clothing and tires,” says Tracey Woodruff, Ph.D., MPH, professor in the Department of Gynecology and Reproductive Sciences, and the director of the Reproductive Health and the Environment program at UCSF.

How plastics get into your body

These tiny plastic pieces — and the chemicals they leach or let out as the plastic breaks down — enter your body through drinking and eating, absorption through your skin, and even the simple act of breathing, Woodruff says. That’s because plastic can release little bits of itself into things it comes into contact with.

For example, a salmon may consume plastics in the ocean, which accumulates in its body and then enters yours when you eat it. Or milk goes through plastic tubing during the milking process, then gets stored in a plastic bottle at the store. Nonstick cookware and plastic cutting boards that are damaged can also release plastic pieces and plastic-related chemicals into food during preparation. Heating food in plastic containers can cause plastic chemicals to break down into food as well.

The scarier part? These plastics don’t necessarily leave your body quickly. Instead, they can accumulate in organs and fat tissue (microplastics are particularly attracted to lipids). “If we have more fat, the concentration of these chemicals may be higher,” says Dr. Tamiko Robin Katumoto, M.D., clinical associate professor at Stanford and co-leader of the Food Systems, Health, and Environment Working Group.

How do microplastics harm your health?

You probably know intuitively that you don’t want plastic circulating in your body, but what’s it really doing to you? Plastic is a very complex chemical, says Katumoto. Potential harms come on two fronts, she explains: One, from the plastic particles themselves, and two, the chemicals that plastics can leach into the body.

This build-up of microplastics themselves can cause inflammation and change how your body functions. And then there are the dangerous chemicals found inside the microplastics. Some examples include phthalates, a chemical found in many products, such as cosmetics, cleaning supplies, and personal care items. “Phthalates disrupt sex hormones and may contribute to obesity,” explains Katumoto. Additionally, some plastics like tupperware contain BPA (bisphenol A) to make the material harder, which also has hormone-disrupting effects. And earlier this year black plastic cooking utensils made headlines because they are made from recycled electronic waste — something that contains flame retardants.

A systematic review shows microplastics may lead to a variety of health problems, including harm to the reproductive system (especially sperm health), digestive, and respiratory health, as well as possibly contributing to lung and colon cancer. In part, this may be because these plastics and their chemicals increase oxidative stress and chronic inflammation and suppress immune function. “More studies are needed,” says Woodruff, one of the authors on the research, “but it’s enough to be concerned, especially because plastic production has been projected to triple by 2060.”

What you can do about microplastics

First, we’ll get the bad part out of the way: You probably won’t be able to rid your body of all plastics. In modern life, plastic is everywhere. And much of the time, it helps make our lives easier. So the goal here is not to live a life where you never touch a single plastic item. Instead, as you try to minimize plastic exposure, “fit into your lifestyle what you can manage,” says Woodruff. You can make changes on two fronts: reducing and avoiding plastics as much as you can and helping your body get rid of microplastics more quickly. Here are some habits you can start with today:

Reduce plastic exposure

By relying less on plastic and plastic materials, you may be able to lessen the amount that makes it into your body. “Let’s turn off the hose,” says Katsumoto.

• Don’t microwave in plastic: Heat can cause plastics to leach chemicals into your food. Reheat your food on a microwave-safe ceramic dish instead.
• Limit buying packaged foods: To the best of your ability, try to buy whole foods that are not in plastic packaging. This can be daunting, but small shifts might be bagging a head of broccoli in a reusable produce bag versus buying pre-chopped florets in a plastic, microwaveable bag.
• Avoid single-use plastics: Instead of a disposable plastic water bottle (or even a reusable plastic water bottle), fill up a stainless steel or glass bottle with H20. Bring a reusable mug for your coffee instead of sipping from to-go cups, which are made of plastic or plastic-coated paper. Leave a set of metal utensils at work instead of relying on plastic forks and spoons. Store food in glass storage containers rather than plastics, especially those old plastic take-out containers that degrade easily.
• Change your cooking equipment: If it’s doable for you, switch out plastic cutting boards and cooking utensils (like black plastic ones) to materials like wood. Replace non-stick skillets — especially if scratched or chipped — with materials like stainless steel or ceramic.
• Keep things clean: Microplastics like to hang out in dust in your house, says Woodruff, who recommends cleaning with a wet mop and HEPA filter vacuum. While you’re at it, avoid wearing shoes into your house — leave them at your door when you come in (and encourage guests to do the same). “There’s a plastic chemical used in shoe rubber that can be measured in peoples’ bodies,” says Woodruff.
• Eat more plants: “When you look at the limited studies out there, fattier foods like animal products tend to have a higher proportion of [plastic chemical] contamination,” says Katsumoto. Dairy (due, in part, to tubing used in milk production), fish and seafood (due to plastics in the ocean), and animal meat (especially fattier meat), tend to be more problematic. Microplastics are also found in plant foods like fruits and vegetables, but in much lower levels, Katsumoto says. Shifting to a more plant-based diet can help reduce your exposure.
• Cook more at home and reduce UPFs: “Food you prepare inside your home tends to have less contact with plastic-related materials,” says Woodruff. “Specifically, our research shows that food cooked at home has less phthalates compared to fast food or restaurant food." Likewise, microplastics can also come off of food packaging, another reason to reduce intake of ultra-processed foods.

Help your body get rid of plastics

Next up: Certain habits may encourage your body to get rid of microplastics, or fight off their harmful effects. (Bonus: They’re good for you in other ways, too!)

• Load up on fiber: Fiber does something really great with microplastics: It can bind to the particles so that your body can get rid of them through your waste, says Katusumoto. We need more research to validate this, but theoretically, this is a promising perk of fiber, and another reason to focus on plant-based eating.
• Focus on cruciferous veggies: These types of veggies, such as broccoli, cauliflower, Brussels sprouts, and kale, contain high levels of sulforaphane, a compound that supports the liver’s detoxifying system, says Katusoto. “We may be able to partly mitigate the impact of some of the chemicals found in plastics by eating these antioxidants,” she says.
• Eat bright foods: Fruits and vegetables that contain anthocyanins like berries, plums, red cabbage, red grapes, purple sweet potato, and pomegranate, may be especially good for helping counteract the negative effects of endocrine-distrupting chemicals in plastics, research shows.