Ladykiller: Artificial sweetener proves deadly for female flies

June 27, 2016 by Frank Otto, Drexel University
A fruit fly on a compost pile. Credit: Photo by John Tann.

Continuing their research into potential ingredients for human-safe pesticides, Drexel University researchers recently found an artificial sweetener that, while harmless for male fruit flies, proved particularly lethal for females.

Past research conducted by Drexel College of Arts and Sciences' Sean O'Donnell, PhD, professor and associate department head of Biodiversity, Earth & Environmental Science (BEES) and Daniel Marenda, PhD, an associate professor of Biology, indicated that erythritol, an in name-brand products like Truvia, is poisonous to fruit .

Building on that research—which had originally been inspired by the science project of Marenda's son—the Drexel team tested four different polyols (sugar alcohols) to see which shortened the lifespans of the Drosophila melanogaster (fruit flies), indicating toxicity in insects.

As expected, erythritol was effective in killing off the flies. Two of the polyols—malitol and xylitol—showed no noticeable effect on the flies. But the fourth artificial sweetener, D-mannitol, was found to be poisonous only to female flies.

"We are excited but a bit puzzled by this finding," said O'Donnell.

O'Donnell and Marenda were joined by Kaitlin Baudier, a Drexel biology graduate student, in publishing the findings of their study in the Journal of Insect Science under the title "Non-Nutritive Polyol Sweeteners Differ in Insecticidal Activity When Ingested by Adult Drosophila melanogaster (Diptera:Drosophilidae)."

For the study, flies were divided into groups and assigned a sweetener for their consumption. Two control groups were also a part of the study: One group had sucrose, a naturally occurring sugar, mixed in with its food, the other control had nothing mixed in its food. Using the flies' normal food to present the sweeteners was important because it showed that the flies were not simply avoiding eating.

Data indicated a steep decline in the numbers of flies who consumed erythritol once they were fed the sweetener. They began dying at a significant number around the fourth day of the experiment. By the end of day six, they'd all died.

"We confirmed that erythritol is toxic to insects—specifically fruit flies—when ingested," O'Donnell said. "The strongest effect is specific to erythritol. Other similar compounds were either not effective at reducing fly longevity or had limited effects."

D-mannitol is a sweetener typically used to sweeten gum or add a coating to hard candy or dried fruit for those with diabetes. The flies given it didn't display any noticeable signs of toxicity for roughly a week.

It was around the seventh day of the experiment when the D-mannitol group began to display a higher death rate. By day 12, it was a statistically significant difference. And on day 17, the last day of the experiment, the flies that consumed D-mannitol were half as likely to survive as the flies in other groups (flies given malitol and xylitol displayed no significant difference in lifespan from the control groups).

Although D-mannitol doesn't appear to be as highly toxic for flies as erythritol, its lethality for female flies is significant: female flies were five times more likely to die than males after consuming D-mannitol.

"Implications for insect control could exist, because females are the real reproducers and affecting females can reduce population growth," O'Donnell said. "Furthermore, many social insect pests—such as Hymenoptera, which includes ants and wasps—have female-based colonies."

It's unclear why the effects were skewed so firmly against female flies. O'Donnell hopes to study insect D-mannitol consumption further, as there are "potentially very interesting [aspects] from an insect reproductive physiology perspective."

Nothing in the study should influence whether or not someone adds artificial sweetener to their coffee or tea, however.

"All the compounds we tested are vetted and human-safe," O'Donnell explained. "The effects on insects don't really inform human health issues in this case."

Explore further: You catch (and kill) more flies with this sweetener

More information: Sean O'Donnell et al, Non-Nutritive Polyol Sweeteners Differ in Insecticidal Activity When Ingested by Adult(Diptera: Drosophilidae), Journal of Insect Science (2016). DOI: 10.1093/jisesa/iew031

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not rated yet Jun 28, 2016
I think we need to wait for more information why these sweeteners are poisonous to insects. Only then are we more able to determine how poisonous they are to other animals, including us humans. I myself think that it is better to stay away from artificial products as much as possible, since we obviously have too little data about what effects they might have.
4.5 / 5 (2) Jun 28, 2016
related oddity:

Aspartame was originally a VERY effective CROP DUSTING POISON.

Not really a effective sugar substitute..... but more of a slow drip depopulation agenda.

Via long term low level debilitation.

It's been working well so far.....

It took 14 years to get aspartame approved for human consumption. The attempts bankrupt at least one of the companies involved.

When it was finally approved, the scandal was so bad that the entire legal premise and operational parameters of the FDA was changed,

Many FDA staff were fired due to collusion and falsification, etc,

Many a related study was found to be wholly falsified (again!!),

And quite a few of the ex-FDA staff ended up working for the same company who managed to get aspartame approved.

None of this is even remotely a fib or exaggeration. So look into it, and ask yourself, exactly what the hell is going on when a pure toxin of a serious nature is somehow approved for being a sugar substitute.
5 / 5 (1) Jun 28, 2016
Sucralose discovered while searching for new insecticides. "In test animals Splenda produced swollen livers, as do all chlorocarbon poisons, and also calcified the kidneys of test animals in toxicity studies. The brain and nervous system are highly subject to metabolic toxicities and solvency damages by these chemicals. Their high solvency attacks the human nervous system and many other body systems including genetics and the immune function. Thus, chlorocarbon poisoning can cause cancer, birth defects, and immune system destruction. These are well known effects of Dioxin and PCBs which are known deadly chlorocarbons."
5 / 5 (2) Jun 28, 2016
TPTB deemed it necessary to introduce artificial selection forces to replace natural selection forces that have been mitigated with modern lifestyle. Hence elites buy organic food at stores like Whole Foods while plebeian unwashed masses consume McShitlets and render themselves as foundation for Obamacare guinea pigs as they slowly rot from the inside out

These eugenic measures will need to be redoubled to keep more impulsively fertile breeds of humans on a leash, according to the small families that control USA chemical companies

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