Hundreds of species of fish are ingesting plastic, including some that humans eat, a newly published study found. The team of researchers, which did a review of the growing scientific literature on this topic, found the amount of plastic that ocean fish consume is rising as well. There is already evidence that microplastics in fish stomachs migrate to muscle tissue, which people eat. "'Out of sight, out of mind' is not an effective response to ocean pollution – especially when it may end up on our plates," they write.

Data show that Pfizer’s COVID-19 vaccine is effective in obese people, but concerns remain. Obesity medicine physician Cate Varney from the University of Virginia writes that previous studies showed flu shots are less effective on people who have excess weight or are obese. Pfizer’s clinical trials for the COVID-19 vaccine included obese people, which provides some comfort that it provides protection, but there are questions over how long it will remain effective, she explains.

Microbes in your gut can influence how well drug therapies work. Scientists transferred fecal matter from melanoma patients who responded well to immunotherapy to patients for whom those therapies failed and saw an improvement post-transplant. The experiment was designed to test whether the health of a person’s microbiome – the trillions of bacteria in our digestive tract – can boost a cancer patient’s immune response and the effects of drugs. Medical oncologist Diwakar Davar from the University of Pittsburgh explains the results of the trial and the broader link between disease and the microbiome.

See our full list of the latest science and research news below. There’s also a link to our weekly podcast featuring a story on the three missions to Mars that are all arriving this month.

Martin La Monica

Deputy Editor

A biologist examines microplastics found in sea species at the Hellenic Centre for Marine Research in Greece, Nov. 26, 2019. Louisa Gouliamaki/AFP via Getty Images

Hundreds of fish species, including many that humans eat, are consuming plastic

Alexandra McInturf, University of California, Davis; Matthew Savoca, Stanford University

As more and more plastic trash permeates the oceans, fragments are making their way into fish and shellfish – and potentially into humans.

Patients with overweight or obesity issues make up more than 70% of the U.S. population. Peter Dazeley via Getty Images

Will the COVID-19 vaccine work as well in patients with obesity?

Cate Varney, University of Virginia

Americans with excess weight and obesity have been hit hard by COVID-19. Now there is reason to believe they may not get the same protection from the vaccines.

The gut is filled with microbes that can affect human health. ChrisChrisW/iStock via Getty Images Plus

Fecal microbe transplants help cancer patients respond to immunotherapy and shrink tumors

Diwakar Davar, University of Pittsburgh

Whether or not you respond to a certain medicine or therapy doesn't just depend on you. The microbes in your gut play a role in the success or failure of various drugs, including cancer therapies.

Other good finds


An artist’s illustration of the aeroshell containing NASA’s Perseverance rover guiding itself towards the surface of Mars. NASA/JPL-Caltech

Mars: The Conversation Weekly podcast explores why three missions are about to reach the red planet

Gemma Ware, The Conversation; Daniel Merino, The Conversation

Plus what protesters in Belarus want to happen next. Episode 1 of The Conversation's new weekly podcast.