honey bee nutrition

Is high-fructose corn syrup bad for bees?

Lots of myth and misinformation surrounds high-fructose corn syrup (HFCS) and whether it is bad for bees. I decided to do some research to find out what the experts are saying about this American food staple. I came up with a short Q&A.

Q: What is the difference between regular corn syrup and high-fructose corn syrup?

A: Regular corn syrup, also known as glucose syrup, has been used since 1812. Although the preferred processes for making it have changed over the years, it is manufactured by adding enzymes to corn starch. It is basically 100% glucose.

HFCS became available in the early 1970s. It is made by treating regular corn syrup with additional enzymes that convert some of the glucose to fructose. The most popular type is HFCS 55, which is 55% fructose. Also available, but seldom used, is HFCS 90, which is 90% fructose.

Regular corn syrup is often confused with HFCS, which is unfortunate because they are not the same thing.

Q: When and why did HFCS become a popular food ingredient?

A: HFCS became popular during the sugar shortage of the 1970s. Without reliable supplies of sugar, food manufacturing companies turned to a sweetener they could obtain from domestically-grown corn.

Both types of corn syrup are used in baking. In general, corn syrup is used as a sweetener and a thickener. It is also prized for retaining moisture, helping to maintain the freshness of baked goods. In addition, HFCS is used to prevent crystallization in certain products. As beekeepers know, honey with lots of fructose is slow to crystallize, while honey high in glucose can crystallize quickly.

Q: How is HFCS different from sugar?

A: Granulated sugar contains 50% fructose and 50% glucose. The two molecules are bound together to form the disaccharide known as sucrose. Sucrose is found naturally in many plants and in nectar.

HFCS contains 55% fructose and the rest is glucose. However, instead of being bound together, the two molecules remain separate.

Q: Why is HFCS bad for humans?

A: According to the Mayo Clinic, HFCS isn’t any worse for humans than sugar. When we eat sugar, the first thing our digestive tract does is break down the sucrose into fructose and glucose, ending up the same way HFCS starts out. By the time they enter the bloodstream, the are virtually identical. The Mayo Clinic site says, “At this time, there’s insufficient evidence to say that high-fructose corn syrup is any less healthy than other types of sweeteners.”

Q: Why do some doctors say both refined sugar and HFCS are bad for our health?

A: The problem with both types of sweetener seems to be the fructose component. Glucose is immediately available to our cells for energy or it can be stored as glycogen. But our cells cannot use fructose directly. Fructose most first be converted to glucose by the liver. If it’s not needed immediately, it is stored as fat. Some nutritionists believe that since we have a greater propensity to store fructose as fat, we should avoid foods that are high in fructose. Others disagree, but since table sugar is 50% fructose and HFCS is 55% fructose, they are very similar in their effect.

Q: But what about bees? Is HFCS bad for them?

A: It is important to remember that bees are not mammals. Their digestive and metabolic systems are different from ours in many ways. A bee’s source of food energy is nectar—a substance made of sucrose, glucose, fructose and other simple sugars.

When bees collect nectar, the sucrose portion is immediately broken down into fructose and glucose by their salivary glands. These simple sugars are added to the others found in nectar and stored as honey. As mentioned earlier, some of this honey is extremely high in fructose. Honey bees have evolved to thrive on a high-fructose diet with no ill effects—in fact, they require it.

Honey bees live a very short lifespan, and with the exception of winter bees, most never accumulate significant fat reserves, regardless of how much fructose they eat.

Q: Doesn’t HFCS contain HMF (hydroxymethylfurfural)?

A: It can, especially if it gets old or is stored at high temperatures. But anything with lots of fructose, including sugar syrup and honey, can also contain HMF if not handled and stored properly.

Q: I thought HFCS is made from genetically modified corn.

A: It is. Both HFCS and beet sugar are usually produced from GMOs, at least in the U.S.

Q: So you think HFCS is okay for honey bees?

A: Let’s slow down, a bit. While I do not believe HFCS by itself is harmful to honey bees, I think a lack of honey probably is. A diet made of mostly HFCS would lack the vitamins, minerals, pollen, and micronutrients found in honey. All of the little extras help the bees build a strong immune system, among other things.

Honey bees need to eat honey. Period. If you run short of honey, or want to add a supplemental food supply, I think HFCS, handled properly, is fine. But for the long term, your bees will need more nutrition than HFCS can offer.

Honey Bee Suite

Used sparingly, high-fructose corn syrup is not bad for bees.

Used sparingly, high-fructose corn syrup is not bad for bees. Image by Myriam Zilles from Pixabay


    • Hi Rebecca,

      Yes. This paper says that the constituents in honey enhance the function of immunity genes and detoxification genes. The authors conclude, “The widespread apicultural use of honey substitutes, including high-fructose corn syrup, may thus compromise the ability of honey bees to cope with pesticides and pathogens and contribute to colony losses.”

      Exactly! This is why I say in my final paragraph that high-fructose corn syrup should never be used in place of honey, but only as a supplement or emergency feed. The same would go for humans. You can eat a candy bar as emergency rations or an occasional treat, but you wouldn’t remain healthy if that’s all you ever ate. It comes down to moderation in all things.

  • Sorry to be the doubting Thomas but when you wrote: “The human effects of a high-fructose diet are slow to accumulate, requiring many years to produce impaired health.” — you offered no citations. Upon what do you base this?

    I easily found: 1) fructose intake at normal population levels and patterns does not cause biochemical outcomes substantially different from other dietary sugars and 2) extreme experimental models that feature hyperdosing or significantly alter the usual dietary glucose-to-fructose ratio are not predictive of typical human outcomes or useful to public health policymakers.

    see: Challenging the Fructose Hypothesis: New Perspectives on Fructose Consumption and Metabolism. John S. White. Advances in Nutrition, Volume 4, Issue 2, March 2013, Pages 246–256,

    • According to the Mayo Clinic (https://www.mayoclinicproceedings.org/article/S0025-6196(15)00040-3/abstract), “Data from animal experiments and human studies implicate added sugars (eg, sucrose and high-fructose corn syrup) in the development of diabetes mellitus and related metabolic derangements that raise cardiovascular (CV) risk. Added fructose in particular (eg, as a constituent of added sucrose or as the main component of high-fructose sweeteners) may pose the greatest problem for incident diabetes, diabetes-related metabolic abnormalities, and CV risk.

      • re: According to the Mayo Clinic.
        They recommend “reducing intake to 5% of total calories (the level now suggested by the World Health Organization).” In my view, the problem is not so much the type of sugar but eating way too much sugar.

  • Nice blog… I have fed HFCS as a part of research to bees… and observed it’s not fruitful as brood rearing is hampered. Not utilized as fast as glucose and sugar. Ferments also. Pungent smell in feeder during rainy season or summer. Need to use fresh every month, cannot store long at room temp… Also affected honey. Had higher HMF. But feeding @ 750 ml/week / colony did no impact but no growth only colonies could survive… I will publish an article soon…

    • Mandeep,

      I reiterate that honey bees need honey, but HFCS used as an occasional supplement or emergency ration does no harm. It should never be used in place of honey for long-term and continued feeding. I look forward to reading your paper.

  • What can be done to make alternative/winter food sources more nutritious? Would you think supplementing with a pollen patty and adding apifit (or similar) would be sufficient for “shorter” periods of 1-2 months, maybe during a long winter?

    • Mike,

      I like to use a pollen patty in addition to a sugar board as emergency feed. I put it above their honey supply in case they go through that too quickly. I sometimes add Honey-Bee-Healthy or something similar to the feed. I’ve used them for years now and have many times overwintered 100% of my colonies. You can see my set-up here: A non-cook candy board.

  • How about the elephant in the room: GMO’s. Especially Glypsolate! Studies done by the chemical companies should be suspect in my book!

    • Yes, I’m suspect of anything written by a chemical company. I personally don’t eat or use GMOs including HFCS, but I’m hard pressed to find clear evidence of their danger. I feel the push/pull between my emotions and my reasoning.

  • My issue with HFC’s (besides the many health reasons to limit sugar) is that demand for cheap sweeteners is one more prop for subsidized monoculture farming, which destroys wildlife (incl pollinator) habitats, requires & exposes insects to pesticide, and degrades soil and water.
    Shady Grove Farm
    Corinth, Kentucky

  • Hi Rusty, I was watching a video of a popular beekeeper that was showing how to make concentrated sugar syrup(honey consistency), by boiling as with candy making to a temp. of 230F. He claimed that the bees could put this in the cells and that it was almost immediately able to be capped. Is this good, bad, or ugly?

    • Richard,

      Beekeepers have been cooking sugar syrup for ages and their colonies survived in spite of it. However, many beekeepers now believe that the accumulation of HMF in cooked syrup will kill some of the bees. So even though the colony survives, it’s not as strong as it could be. The Cooperative Extension Service says this:

      “To avoid dangerous levels of HMF, use cane sugar/water syrup – 50% and do not heat past 100 degrees F. Feed only fresh syrup to avoid HMF accumulation.

      I do not ever heat syrup anymore and my bees do fine. I wouldn’t mess with this advice. Bees in winter don’t usually put anything in cells anyway, they just eat it or not.

      I nearly always overwinter 100% of my colonies, so I’m not eager to change what works for me.

  • Thanks Rusty,

    This was for fall feeding after flow to hives that were light, not winter. I usually use warm tap water and I get 3:2 sugar:water to mix with a lot of stirring, and this is how I mix for any time of the year. I have not had to fall feed yet, but you never know. This is my 6th year and I’m at 5 hives and I haven’t lost a hive over winter, so I’m not changing either.

    • Juan,

      You want the sugar to be white. Both brown sugar and even organic sugar (which is generally evaporated cane juice) have many more solids than refined white sugar. This may cause honey bee dysentery if the bees cannot fly for prolonged periods in the winter. I’m not familiar with piloncillo.

  • Might be good to note that bees can’t digest turbinado or other brown sugars. Most regular organic sugars even have that component.

  • My concern is not just the bees, as much of food raisers seem to prefer the cheapest feed source they can find for their stock. The same as the legislative loopholes that almost sanction the food industry to be able to sell cardboard as long as they add 3-4 vitamins (enhanced!!!), and plenty of flavor, regardless of the nutritional or ethical value. Originally done to keep food prices down, it evolved to produce an exceptionally high profit margin, sacrificing the long-term health prospects while producing latent effects of generational pre-natal malnutrition. The illnesses it spawned due to pre-conception malnutrition has been verified in NIH research, noting that enhanced supplementation 6 months prior to conception prevented or repaired almost 900 disease symptoms proliferated among animals in generational research trials.

    The point is “What effect does straight industrialized “white refined sugar” have on the quality value of the honey end product which WE consume; and what effect does if have on the nutritional health of “humans”. If its mechanisms are based off of “EMPTY” caloric energy. Would you prefer giving your child an egg or a Twinkie to start the day off of before school?

    Note: Check: Paul Stamets and his observations of bees raiding his Garden Giant mushroom patch, sucking up all the nectar for 40 days straight, digging out the wood chips to get to more. Stamets, said he realized the analogy of why bees made hives in rotting logs; it was so they could get to the essences the fungi/mushrooms produced breaking the logs down, as well as the protective sap the bees made propolis to protect their homes with. None of which they have access to with artificial hives.

    • Mey,

      You write, “What effect does straight industrialized ‘white refined sugar’ have on the quality value of the honey end product which WE consume; and what effect does if have on the nutritional health of ‘humans’?”

      Any hive product containing refined sugar is not honey and cannot be sold as honey. Honey, at least by definition in the US, is made from the nectar of flowers and nothing else. White sugar as a supplement is fed to bees when no nectar collection is occurring, such as in the winter.

  • I apologize for the length. I simply wanted to suggest fructose based on a healthier source or more whole fruit/food-based not merely the fruit flesh or sap based isolate. Example: the vivifying power the fruit seeds, rind, pericarp as well as the flesh as a source. The same with using the healthier sweeteners Ex. Coconut sugar which was said in a comment might be too heavy for the bees. Perhaps adjustments in dilution percentages might correct that.

    Note: For info on the above veterinary nutrition research at the NIH see: Joel D. Wallach DVM BS ND.

    PS: Paul Stamets’, university research found his methods extended the working life of bees.

  • Hello. I am saddened and disgusted by the practice of clipping the wings of the queens. Are there certain brands that don’t do this? We try to buy local honey from our farmers market. During winter months we run out and have to buy elsewhere. Any advice will be appreciated. Thank you.

    • It’s impossible to say. Some beekeepers do it and some don’t. If it’s any consolation, I hardly hear of it anymore, so I don’t think it’s very popular.

  • Rusty,

    Good analysis.

    My objection to HFCS is that it supports industrial agriculture, which we know for a fact is bad for bees, other pollinators, and wildlife in general, both thru pesticide use and habitat loss.

    Shady Grove Farm
    Corinth, KY

  • Hello Rusty,

    Last fall I found regular corn syrup that does not have HFCS. (Golden Barrel 42DE Corn Syrup)

    I have not been able to find out I’d this is safe to feed bees.

    I would appreciate your thoughts.

    Thank you,

    • Bob,

      Hydroxymethylfurfural (HMF), the thing that’s bad for bees, occurs at much higher levels in HFCS than in regular corn syrup. HMF is produced from the dehydration of hexose sugars (inulin, cellulose, glucose, fructose and sucrose) under acidic conditions. But it seems that fructose produces more of it than glucose. Because regular corn syrup is 100% glucose, it stores better at high temperatures and over long periods, so it is better for bees (and better for us, too).

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.