Neanderthals’ meat-only diet should have killed them; scientists finally reveal how maggot menu kept them alive

‘Would you rather eat slimy maggots or crunchy beetles?’ Survivalist Bear Grylls once answered Entertainment Weekly without hesitation: maggots slide down easier. It now appears Neanderthals may have made a similar choice tens of thousands of years ago. Long believed to have eaten like apex predators, Neanderthals gorged on meat in a manner rivaling lions and hyenas.

Chemical traces in their bones seemed to confirm a diet dominated by fresh flesh, placing them firmly at the top of the prehistoric food chain. But new research paints a less glamorous and far more unsettling picture.

Instead of endless cuts of fresh meat, their diet may have included decomposed animal flesh teeming with fly larvae. Rich in fat and nutrients, these wriggling snacks were likely more than a desperate last resort. Regular consumption of maggots could explain the puzzling chemical signatures in Neanderthal remains and reveal that their true menu was far less appetizing than once imagined.


The study, led by Melanie M. Beasley, Department of Anthropology, Purdue University, West Lafayette, IN, with colleagues, was published in Science Advances on July 25, 2025.

What the research suggests and questions

In an article in the Conversation, the lead author explains, While it’s possible for humans to survive on heavily meat-based diets, as seen among northern hunter-gatherers like the Inuit, our bodies can’t handle the same extreme protein levels that large predators thrive on. “But as a group, hominins—that’s Neanderthals, our species, and other extinct close relatives—aren’t specialized flesh eaters. Rather, they’re more omnivorous, eating plenty of plant foods, too,” she wrote.

Eating too much protein without enough other nutrients can cause “rabbit starvation,” a dangerous condition that can even be fatal. So how do we explain the chemical signatures in Neanderthal bones that suggest they were thriving on huge amounts of meat?

What the chemistry reveals

Nitrogen isotopes in ancient bones act as markers of diet, with higher levels of nitrogen-15 (δ¹⁵N) usually signaling a meat-heavy lifestyle. Fossils of Neanderthals and early Homo sapiens consistently show δ¹⁵N levels as high as large carnivores. But researchers discovered that maggots feeding on rotting animal tissue can inflate δ¹⁵N values dramatically, in some cases nearly four times higher than herbivore baselines.

This suggests Neanderthals’ “carnivore-like” signatures may not have been the result of pure meat consumption but instead came from diets that included maggots and fermented animal foods.

Why maggot menu made sense

Fly larvae were abundant, easy to harvest, and nutritionally dense. Like northern Indigenous foragers who prized decomposed, maggot-infested foods as delicacies, Neanderthals may have relied on such resources regularly. Eating maggots also reduced the risk of protein poisoning, or “rabbit starvation,” a danger for humans consuming too much lean meat without fat.

In this light, maggots weren’t pests but “bonus calories” that made stored or cached food both edible and beneficial.

Culture, taste, and survival

Ethnographic parallels show that many Indigenous groups embraced putrefied foods, even when outsiders found the smell nauseating. Neanderthals may have practiced butchering, storing, fermenting, and cooking in ways that distinguished their diets from those of non-human carnivores.

By eating decomposed meat, fatty tissues, and the maggots within, Neanderthals maximized nutrition and survival, turning what might disgust us today into a dietary advantage.

Everything is not solved yet

Fly larvae are a common, easily obtained, nutrient-dense, and fat-rich insect resource that would have been advantageous for Neanderthals and early Homo sapiens to fully utilize, much like modern foragers. The high δ¹⁵N values found in Neanderthal remains, however, cannot be explained by maggots alone.

And the exact contribution of maggots remains unclear. How much would Neanderthals have needed to eat? Did the nutritional profile change over time as foods fermented? And how did these practices evolve alongside cooking and food storage traditions?