Scientists studied how different diets affect the tiny bacteria living in honey bee stomachs. They compared wild African honey bees with bees raised in clean conditions and fed different types of food—including pollen, casein (a milk protein), and sterilized versions of these foods. The researchers discovered that what bees eat dramatically changes which bacteria live in their guts and how well those bacteria help with digestion. This research could help beekeepers keep their bees healthier by understanding the connection between bee food, gut bacteria, and bee nutrition.

The Quick Take

  • What they studied: How different types of food change the bacteria living inside honey bee digestive systems and whether those bacteria help bees digest food better
  • Who participated: Young worker honey bees from African savannah regions (Apis mellifera scutellata), both wild-caught bees and laboratory-raised bees fed four different diets
  • Key finding: Bees fed pollen had different gut bacteria than bees fed other proteins, and the bacteria in laboratory-raised bees showed more variety than wild bees. Importantly, pollen brought its own special bacteria into the bee’s stomach that helped with digestion
  • What it means for you: If you keep bees or care about bee health, understanding what bees eat and how it affects their gut bacteria could help us keep bee colonies stronger and healthier. However, this is early research on African bees specifically, so more studies are needed before making major changes to bee care

The Research Details

Scientists took young honey bees and raised them in special cages under very clean conditions. They divided the bees into four groups, each eating a different diet: fresh pollen from sunflowers, a protein powder called casein, sterilized (cleaned) casein, or sterilized pollen. They also collected wild honey bees from nature during flowering season. Then they used advanced DNA testing to identify exactly which bacteria lived in each bee’s gut and compared the results between groups.

The researchers used a technique called DNA metabarcoding, which is like taking a fingerprint of all the bacteria present. Instead of growing bacteria in dishes (which is slow and misses many types), this method reads the genetic code of bacteria directly from the bee’s digestive system. This lets scientists see the complete picture of the bacterial community quickly and accurately.

By comparing wild bees to laboratory bees, and bees eating different diets, the scientists could figure out which bacteria come from pollen, which bacteria are naturally in bee guts, and how diet changes the bacterial community.

This research approach is important because it shows us that bee health depends on a three-way relationship: the bee, the bacteria in its gut, and the food it eats. Previous studies didn’t fully understand how African savannah bees’ gut bacteria work, so this fills an important gap. Understanding these connections could help beekeepers prevent diseases and keep colonies healthy by managing bee nutrition better.

The study used modern, reliable DNA testing methods that are considered the gold standard for identifying bacteria. The researchers compared multiple groups (wild bees, laboratory bees, different diets) which strengthens their conclusions. However, the study doesn’t specify exactly how many bees were tested, which makes it harder to judge if the sample size was large enough. The research was published in a respected scientific journal focused on applied microbiology, suggesting it passed quality review. The main limitation is that this focuses specifically on African honey bees, so results may not apply to other bee species.

What the Results Show

The most surprising finding was that laboratory-raised bees actually had MORE variety of bacteria in their guts than wild bees, which seems backwards at first. This happened because the laboratory bees were raised in very clean conditions, so they didn’t have the same dominant bacteria that wild bees naturally pick up. In wild bees, a few bacterial types took over and crowded out others.

The researchers found that three bacterial types were most common across all groups: Commensalibacter, Bartonella, and Bifidobacterium. These appear to be the “core” bacteria that most honey bees carry. Interestingly, a bacteria called Gilliamella, which scientists expected to find in all bees, was completely missing from these African bees. Another bacteria called Apibacter showed up only in wild bees, suggesting it comes from nature.

When bees ate pollen, special bacteria from the pollen itself moved into their guts—bacteria like Devosia and Pedobacter. This is important because it shows that bees don’t just eat pollen; they also eat the bacteria living on pollen, and those bacteria can help with digestion. When bees ate sterilized (cleaned) pollen or casein, these pollen-associated bacteria didn’t appear, proving they come from the pollen itself.

The bacteria in bee guts produced important digestive enzymes (special proteins that break down food). These enzymes help bees digest complex sugars, absorb nutrients, and break down carbohydrates—all essential for bee health and energy.

The study found that sterilized versus non-sterilized food made a big difference. When pollen was sterilized (killing its bacteria), the gut bacteria community changed significantly. This shows that the bacteria living on pollen are important for shaping what bacteria end up in the bee’s gut. The type of protein source also mattered—bees eating casein (milk protein) had different bacteria than bees eating pollen, even though both are protein sources. This suggests bees’ guts are very responsive to diet changes.

Previous research on European and Asian honey bees identified a core set of bacteria that seemed universal. This study challenges that idea by showing African savannah bees have a different bacterial community. The finding that pollen-associated bacteria can colonize bee guts is relatively new and opens up possibilities for improving bee health through diet management. Most previous studies didn’t look at how diet specifically shapes the bacterial community, so this adds important new information.

The study doesn’t report the exact number of bees tested, making it hard to know if results are reliable. The research only looked at African savannah bees, so we don’t know if these findings apply to other bee species or subspecies. The laboratory conditions were very artificial—real bees encounter many more bacteria and food sources in nature. The study only looked at young worker bees, not older bees or different castes (like drones or queens). Finally, while the study identified bacteria and their potential enzymes, it didn’t prove that these enzymes actually improve bee digestion or health—that would require additional experiments.

The Bottom Line

Based on this research, beekeepers might consider ensuring their bees have access to diverse, natural pollen sources, as pollen appears to introduce beneficial bacteria. However, this is preliminary research, so major changes to beekeeping practices aren’t recommended yet. The findings suggest that probiotic supplements containing pollen-associated bacteria could potentially help bee health, but such products would need testing before use. Confidence level: Low to Moderate—this is early-stage research that needs follow-up studies.

Beekeepers, especially those managing African honey bees, should find this interesting. Researchers studying bee health and disease resistance should pay attention. Agricultural scientists working on pollinator health would benefit from these insights. However, if you keep European honey bees, you should wait for similar research on your bee species before making changes. This research is too preliminary for home beekeepers to make major management changes based solely on these findings.

If beekeepers were to adjust bee diets based on these findings, changes to gut bacteria would likely occur within days to weeks, as the study showed diet changes bacteria composition relatively quickly. However, improvements to bee health, disease resistance, or productivity would take much longer to observe—likely weeks to months or longer. This is why follow-up studies are needed to confirm that bacterial changes actually lead to healthier bees.

Want to Apply This Research?

  • Track the pollen sources available to your bees weekly (by plant type and abundance) and correlate this with colony health metrics like brood patterns, food stores, and disease signs. This would help identify if diverse pollen sources improve colony outcomes
  • If using a beekeeping app, log the types of pollen your bees are foraging on and note any changes in colony behavior or health. Over time, this creates a record showing how diet diversity affects your specific colonies
  • Establish a baseline of your colony’s health metrics (disease incidence, productivity, strength) and track them monthly while noting pollen availability. This long-term approach would help you personally observe whether diverse pollen sources improve your bee colonies, even though the research is still preliminary

This research describes laboratory findings about honey bee gut bacteria and should not be used as the sole basis for changing beekeeping practices. The study was conducted on African savannah honey bees under controlled conditions that don’t reflect natural beekeeping environments. Results may not apply to other bee species or subspecies. Before making changes to bee management, feeding, or introducing any supplements, consult with a local beekeeper association, extension service, or veterinarian experienced with bees. This article is for educational purposes and does not constitute professional beekeeping or veterinary advice.