Fruit Flies Live Longer on an Organic Diet
When Ria Chhabra was but 13 years old she heard her parents discussing whether the cost of organic food was worth the benefit. She decided to research the topic for a school science project and during her research noticed there was not enough information to make a clear judgment, so Ria decided to come up with the proof herself. At first Ria tested organic and conventional produce for vitamin C levels (organic had more) but she realized she needed more evidence of benefit, than simply vitamin C levels. So Ria looked on the internet for inspiration on how to conduct a more thorough study and she decided testing fruit flies was ideal due to their short life span, and the well known fact that dietary factors affect fruit fly fertility, longevity and health.
Ria sent out letters to known fruit fly researchers and was excited to hear back from Dr. Johannes Bauer of Southern Methodist University in Dallas, which is fairly close by to her home. Ria conducted the research over the summer at Dr. Bauer's lab.
The flies were fed a homogenized mash of either bananas, potatoes, raisins or soybean. Both the conventional and organic produce was purchased at a Whole Foods store in the area. The study tracked daily a minimum of ten vials per test, each vial contained 25 males and 25 females (only 10 males and 10 females were used per vial for the fertility tests). Rai came to the lab each day to count living or dead flies as well as the number of eggs produced. The graphs speak for themselves...
Length of LIfe Data:
Obviously the raisins kept the flies alive much longer than the soybeans. The startler as to the soybeans, is that the conventional eating soybean flies were all dead after just 10 days, whereas some of the organic eating flies lived till day 18, almost twice as long as the conventional soybean eaters. (Just conjecture, but the early conventional soybean deaths could well be due to the soybeans being GM as well as with possible pesticide residue.)
Out of the four test foods, it appears bananas keep fruit flies alive the longest. The probable reason for little difference between consuming organic or conventional bananas and length of life: there is not much difference between conventional and organic banana pulp as it is covered in a peel which protects the pulp from absorbing the pesticides and fungicides.
Daily egg production.
"Flies fed extracts of any organic produce had significantly higher daily egg production than flies fed conventional diets. Interestingly, flies fed the normal balanced laboratory diet have significantly higher fertility, with an egg production peak between five and ten days, while flies fed the produce extract had steadily declining fertility levels, reminiscent of what is observed with longevity. Due to the extremely short life spans of flies raised on soy diets, flies raised on soy diets were excluded from all subsequent assays." plosone.org
Starvation and stress resistence were also tested, but for a raisin diet, the organic fed flies always faired better. The researchers acknowledge that almost all negative or neutral results were obtained when using raisin diets. "Suggesting the beneficial health effects of organic diets are dependent on the specific food item."* Activity was also measured, and here flies raised on extracts of organic raisin and banana food had higher overall activity than flies fed the conventional diets.*
The data demonstrate that flies raised on organic food extracts by and large performed better on the majority of health tests.
Congrats to high school sophomore, Ria Chhabra, who at the age of 16, had her first scientific paper published.
*Find the study here: www.plosone.org/article/info:doi%2F10.1371%2Fjournal.pone.0052988#pone.0052988.s001
Read more at Southern Methodist University: blog.smu.edu
To test if organic food is healthier than conventionally grown food, they fed one group of fruit flies an organic diet and a second group a conventional diet.
In the lab of SMU biologist Johannes Bauer research found that fruit flies raised on organic foods performed better on various health tests. Flies on organic diets showed improvements on the most significant measures of health, namely fertility and longevity, said high school student Ria Chhabra, who led the study.