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Today we explore how to move the needle on low life expectancy in the United States, learn that weight-loss drugs might also help with migraine headaches and watch a tiny robot snatch up drops of liquid.

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US bombing of Iran’s nuclear sites

On 22 June, the United States bombed underground uranium-enrichment facilities and a nuclear research centre in Iran. Assessing the impact of the attacks requires a combination of decades of experience with the Iranian nuclear programme, access to satellite imagery, weapons knowledge and government contacts, says David Albright, one of the few researchers with the expertise for this task. But they’d rather rely on first-hand inspections, he says. “As nuclear experts, we’d like to see this done with diplomatic agreements.”

Obesity drugs might also tackle migraine

The weight-loss drug liraglutide — a GLP-1 receptor agonist similar to Ozempic — could also help to treat migraines. In a small study, liraglutide almost halved the mean number of days per month people with obesity and chronic migraine experienced a headache. The work didn’t include a control group, so some of the benefit could have been down to the placebo effect, says headache-disorder specialist Lanfranco Pellesi. Still, the results are promising enough to justify a randomized controlled trial to test the effect more thoroughly, he says.

Orcas work together to exfoliate

Southern resident orcas (Orcinus orca ater) can use a piece of kelp to groom one another, an act researchers have coined ‘allokelping’. A pair of the whales place short pieces of seaweed between their bodies and rub themselves together as they swim, which exfoliates them both at once — the first time marine mammals have been seen using a tool for mutual grooming. The behaviour might be useful for getting rid of parasites on the orca’s skin, says marine biologist Sarah Fortune, or a way of regulating their temperature.

How to really make America healthy again

“We are the sickest nation in the world,” said top US health official Robert F. Kennedy Jr in March. “We have the highest rate of chronic disease.” His diagnosis holds some truth: relative to other similarly wealthy nations, the United States has the shortest life expectancy; and chronic disease, including heart disease and obesity, are key contributors. But his plan to ‘Make America Healthy Again’ has so far damaged the public-health system and fails to address several key drivers of ill health, say health-policy specialists. They offer these insights into how to improve life expectancy in the US:

• Tackle substance misuse, car crashes, and suicides and homicides using guns, which kill many more young people in the US than in comparable countries.
• Americans’ lifespans vary dramatically depending on where they live, the economic conditions in that location, and their racial and ethnic identity — so policies must take these population differences into account.
• The US is alone among comparable nations in not having universal health-insurance coverage. This missing piece prevents some people from getting diagnoses and treatment early on.
• Sweeping cuts — for example, to the low-income public health-insurance provider, Medicaid — and efforts to undermine trust in vaccines risk some of the country’s most cost-effective health strategies. Spending on disease prevention is “where the big gains are to be made on population health”, says health-care analyst Thomas Bollyky.

Synthetic protein jams up diseased cells

A synthetic ‘killswitch’ protein, just 17 amino acids long, can jam droplet-like structures that coordinate key cellular processes linked to cancer, viral replication, gene expression and more. The droplet-like structures have no membranes and help organize proteins and RNA molecules so that they can perform specific tasks efficiently and precisely. The killswitch infiltrates the droplets and fixes them in place. In a pair of experiments, researchers found that the killswitch could reduce the proliferation of leukaemia cells in mice and also curtail the production of viral particles in infected cells.

When a student teaches ChatGPT physics

At the end of each semester, physicist and educator Brian Lane gives his students a chance to claw back some points by guiding ChatGPT through their lowest-scoring exam. Lane shares one example, in which the chatbot makes stumbling attempts to answer the question, ‘Why does a ping-pong ball require more time to fall than to rise to the same height?’ The exercise is good at helping to identify strengths and weaknesses in students’ understanding, says Lane. But it also reveals a worrying optimism about ChatGPT’s outputs, which can appear seductively clear and simple while being riddled with faults.