Thanks to Brilliant for supporting this SciShow News video.

You can keep building your STEM skills at Brilliant.org/SciShow with 20% off an annual premium subscription! [♪ INTRO] Figuring out whether or not the foods you’re eating are bad for the planet is… complicated. Maybe you’ve heard about the methane burps of cows, so you decided to cut back on beef and dairy.

You switch to a nice plant-based smoothie, but then you find out those almonds in your almond milk hog tons of water. And that’s not even getting into products like beef substitutes, which can have so many ingredients that it’s hard to unpack the ways they might be draining resources. But a study just published in the journal PNAS this week may have at least some answers.

Researchers at the University of Oxford and their collaborators have estimated the environmental impact of 57,000 food products in the UK and Ireland. Among many other things, their findings suggest that, yes, plant-based alternatives to meat may in some cases have one-fifth to less than one-tenth the impact of meat. Lots of foods have lots of ingredients.

You might be able to make guesses about the environmental impact of a cut of beef or a bag of almonds, but it’s tougher for your favorite cereal or frozen lasagna. Especially since most brands make it hard to figure out where those ingredients come from, and how much of that stuff they use. But the researchers in this study figured out a clever way around that.

In the UK, brands don’t have to tell you the percentage they use of everything, but they do have to specify for key ingredients… say, the “beef” in beef lasagna. And since the ingredient list on the package is required to be listed in order of most to least, the researchers developed an algorithm that could use that info and compare it to similar products to suss out quantities for basically everything. And they compared those amounts to established databases that quantify the impacts of particular ingredients.

They looked at four categories of potential problems: greenhouse gas emissions, water use, land use, and the potential for the foods’ production to build up harmful levels of nutrients in aquatic ecosystems. To make all that information a bit easier to grapple with, they used it to give each food product an environmental impact score between 0 for no impact, and 100 for… bad. Generally speaking, the lowest-scoring products were made of fruits, vegetables, sugar, and flour.

That includes popcorn, vegetarian soups, some cereals and breads, and… you guessed it! Many meat substitutes. Foods made of meat and dairy tended to have higher scores overall, but a closer look at sausages showed that beef and lamb were 240% more impactful than pork, which was twice as bad as chicken and turkey, which were more than twice as impactful as vegetarian and vegan sausages.

Also, and beef jerky got a special shout-out for its extra high score. For foods with middling scores, there was a lot of variability depending on which brand of product you picked. That could be good news!

Those swaps could help many consumers make more planet-friendly choices without major changes to their diets. The researchers also app lied nutrition scores to each food. They found many food categories that provided both good nutrition and low environmental impact, suggesting that healthier choices for us may be healthier for the planet at the same time.

Sugary drinks and treats were a notable exception, though. They are bad for us, but the researchers’ analysis suggested that they aren’t that terrible for the planet. Now, there are some caveats.

This study does not account for where the food came from, since that information wasn’t always available. It also doesn’t take into account all the phases of processing and transport that create our favorite snacks and ready-made meals, although the researchers argue that the agricultural impacts of products are a much bigger consideration than the processing of them. The 100-point scale is also based on 100 grams of a given food… which isn’t necessarily how much someone typically eats of that food at a given meal.

The researchers still want to find better ways to share their tool with consumers, but they hope that it could someday help people make tricky decisions about the best foods for themselves and the planet. Speaking of things that are pretty tough to do, many people need support when they are trying to quit smoking or drinking. And there’s some good news on that front.

A clinical trial published last week in the journal JAMA Network Open suggests that three medications commonly taken to help stop smoking might also have a role to play in reducing problem drinking. The researchers followed over 300 people with HIV over the course of a year. At the beginning of the study, the participants self-identified as engaging in risky drinking and daily smoking, and they were willing to change those behaviors.

The participants were all given medications known to help people stop smoking. One treatment was nicotine-replacement therapy. Other participants got the drugs varenicline or cytisine, which both bind to human nerve receptors to partially mimic the effects of nicotine.

There was no group that got only a placebo, but participants did get combinations of treatment and placebo. The researchers wanted to validate the two medications’ efficacy compared to nicotine replacement in a large group of people with HIV, since their effectiveness in folks with comorbidities is less well studied. Concerns about whether the drugs will work often exclude people with HIV from treatment to help them quit smoking or drinking.

They were also interested in understanding the effect the drugs might have on participants’ alcohol consumption. Varenicline is already known to reduce alcohol cravings and consumption, but cytisine’s effect hasn’t been studied. Nicotine-replacement therapy was meant to be the control in their study, since it’s never been used to curb alcohol consumption.

But to their surprise, the researchers didn’t find a difference between the three medications. All of the groups showed improvements in their alcohol consumption after three months. Participants reduced their heavy drinking days on average, and 21% of participants stopped drinking altogether during that period.

The design of the study, though, means that there are some questions we can’t answer. For example, all participants received medication known to help them stop smoking. Research ethics don’t allow you to give people a placebo when you could give them something that’s known to work.

Which means there isn’t a perfect baseline to know if these people would have reduced their drinking without any medication. The researchers also found a correlation between those who stopped smoking and those who reduced or stopped drinking, so it’s possible that quitting smoking just generally helps people reduce their alcohol consumption. But overall, this is good news!

The researchers think this study is extremely promising for people with HIV looking to stop smoking, since it shows they absolutely can benefit from existing drugs. Beyond that, they say it’s worth looking further into the role of these medications as interventions for people who smoke and want to reduce their drinking. They also say we should look more into the knock-on effects of stopping smoking.

Overall, this looks like a promising route to helping out a specific vulnerable group. And it may lead to research to help even more folks, too. This SciShow News video is supported by Brilliant, an online tool for interactive STEM learning.

Their course, “Scientific Thinking” makes scientific principles more accessible by introducing them through puzzles and games rather than dry technical language. In this course, you can build a bridge to understand the physics of rods and joints, play a game to learn the rules of particle accelerators, and choose your own adventure to learn about river flow dynamics. Brilliant’s courses are designed for people at all levels.

The interactive problems are guided and explained to help you cultivate your curiosity and work your way to mastery. To get started for free, click the link in the description down below or visit Brilliant.org/SciShow. You’ll get 20% off the annual Premium subscription too.

Thanks to Brilliant for supporting this video and thank you for watching! [♪ OUTRO]