For many, the summer holidays mean one thing: countless hours spent lounging outdoors in a state of semi-undress, often accompanied by a raft of insecurities about how our bodies look. As social media amplifies these aesthetic pressures, more and more people are turning to drastic quick-fix diets that promise to shift unwanted weight. The health consequences can be dire.

On the more extreme end of the dieting spectrum is the “mono diet”: eating only one type of food for a determined period of time. Popular choices include watermelon, peach, artichoke or rice, but as nutrition specialist Ana Montero Bravo points out, it doesn’t really matter – eating just one food is never good for our physical or mental health, as it can lead to nutrient deficiencies and exacerbate eating disorders. Plus, it doesn’t even work in the long term.

Online misinformation doesn’t just push people towards dangerous diets – it can also be a weapon of war. The art of “cognitive warfare” dates back to Sun Tzu, but technology has opened up new frontiers for spreading propaganda and untruths. Unlike bombs and bullets, the subtle, malicious shaping of public opinion leaves no physical scars, but it can have very real consequences all the same. Researchers at Lund University lay out some stark examples, and outline how our laws urgently need to adapt to meet this not-so-new threat.

And it’s crunch time for plastic pollution. Representatives are gearing up for a “once in a generation” summit in Geneva in August which could lead to a global treaty on plastics. But if last year’s inconclusive summit in South Korea was anything to go by, scores of industry lobbyists will be trying to prevent it every step of the way.