University of Florida Health researchers have found that putting people on a feast-or-famine diet may mimic some of the benefits of fasting, and that adding antioxidant supplements may counteract those benefits.
Fasting has been shown in mice to extend lifespan and to improve age-related diseases. But fasting every day, which could entail skipping meals or simply reducing overall caloric intake, can be hard to maintain.
“People do not want to just under-eat for their whole lives,” said Mr. Martin Wegman, an MD-PhD in epidemiology student at the UF colleges of Medicine and Public Health and Health Professions, and co-author of the paper recently published in the journal Rejuvenation Research. “We started thinking about the concept of intermittent fasting.”
Mr. Michael Guo, a UF MD-PhD student who is pursuing the PhD portion of the program in genetics at Harvard Medical School, said the group measured the participants’ changes in weight, blood pressure, heart rate, glucose levels, cholesterol, markers of inflammation, and genes involved in protective cell responses over 10 weeks.
“We found that intermittent fasting caused a slight increase to SIRT3, a well-known gene that promotes longevity and is involved in protective cell responses,” Mr. Guo said.
The SIRT3 gene encodes a protein also called SIRT3. The protein SIRT3 belongs to a class of proteins called sirtuins. Sirtuins, if increased in mice, can extend their lifespans, Mr. Guo said. Researchers think proteins such as SIRT3 are activated by oxidative stress, which is triggered when there are more free radicals produced in the body than the body can neutralize with antioxidants. However, small levels of free radicals can be beneficial: When the body undergoes stress — which happens during fasting — small levels of oxidative stress can trigger protective pathways, Mr. Guo said.
“The hypothesis is that if the body is intermittently exposed to low levels of oxidative stress, it can build a better response to it,” Mr. Wegman said.
The researchers found that the intermittent fasting decreased insulin levels in the participants, which means the diet could have an anti-diabetic effect as well.