New research on prediabetics reveals that periodic fasting can guard against cardiovascular diseases, eliminate “bad cholesterol” and reduce weight.
The study, whose results were presented at the 2014 American Diabetes Association Scientific Sessions in San Francisco, earlier in June, comes as the Muslim world is preparing to mark Ramadan, a holy month of ritual and fasting, where observant Muslims abstain from eating and drinking from dawn to dusk.
According to the research, after 10 to 12 hours of fasting time, the body enters into a self-protection mode and starts scavenging for other sources of energy throughout the body to sustain itself—something that on the long haul can help it combat diabetes, among other things.
After multiple episodes of fasting, going into this mode pulls LDL, otherwise known as “bad cholesterol,” from the cells of the body—it’s not clear however how it is used up, but its levels are certainly reduced.
“Though we’ve studied fasting and its health benefits for years, we didn’t know why fasting could provide the health benefits we observed.” says Benjamin Horne, director of cardio vascular and genetic epidemiology at the Intermountain Medical Center, and author of the study. “It is likely that Ramadan fasting would provide a similar level of risk reduction,” he adds.
Prior research done by Horne and his team in 2011 monitored healthy people during one day of fasting and showed that routine, water-only fasting was associated with lower glucose levels and weight loss. Other research by the team has shown that glucose and triglycerides are reduced over the long-term in association with fasting.
“When we studied the effects of fasting in apparently healthy people, cholesterol levels increased during the one-time 24-hour fast,” said Horne. “The changes that were most interesting or unexpected were all related to metabolic health and diabetes risk. Together with our prior studies, this showed that decades of routine fasting was associated with a lower risk of diabetes and coronary artery disease, this led us to think that fasting is most impactful for reducing the risk of diabetes and related metabolic problems.”
Horne launched this new study to look at the effects of fasting in prediabetics over an extended period of time. The study participants included men and women between the ages of 30 and 69 with a least three metabolic risk factors, like large waistlines (the “apple shape” where fat is concentrated in the abdomen), high triglyceride levels, low HDL cholesterol level, high blood pressure or high fasting sugar.
Prior studies have examined obese participants, and focused on weight loss that resulted from fasting, however Horne’s team’s main focus was diabetes intervention—although participants, naturally, also lost weight during this one, precisely three pounds over six weeks.
“During actual fasting days, cholesterol went up slightly in this study, as it did in our prior study of healthy people, but we did notice that over a six-week period cholesterol levels decreased by about 12 percent in addition to the weight loss,” says Horne. “It is unclear how the cholesterol is used during the fasting episodes, but this adds to the list of potential biological mechanisms that fasting affects. What it does suggest is that the health benefits of fasting can be obtained with a less intense regimen than some that are becoming popular today.”
The researches speculate that fasting uses the body’s fat cells for energy, which should help negate insulin resistance. “The fat cells themselves are a major contributor to insulin resistance, which can lead to diabetes,” Horne says. “Because fasting may help to eliminate and break down fat cells, insulin resistance may be frustrated by fasting.”
Horne explains to Nature Middle East that he doesn’t think that abstaining from water, as Muslims do during their fast, will eliminate any benefits of fasting.
“With the duration of fasting being around 16 hours during a Ramadan fast, it is plausible that the lower risk of diabetes is obtained by those engaging in Ramadan fasting,” he says.
Horne adds that they have also studied fasting effects on individuals with a higher risk of chronic diseases. However, in these studies, they have taken the approach of less frequent fasting compared to other groups being studied, but the fasting extends for a longer continuous duration, with one day per week of 24-hour water-only fasting. “With the dawn to dusk fasting of Ramadan, the total duration of the fast is around 16 hours,” he remarks, even less than what these participants endured.
The health benefits of fasting of course are not instantaneous—the episodes of fasting have to recur over a long period of time for results to show.
It is not clear yet what the optimal duration, frequency, or extended period of practice is that is needed or is optimal for the potential health benefits of fasting to be realized, Horne says.
The scientist says that they’re only just starting to examine these questions, and interventional trials will probably still take years to determine what the appropriate balance is between the safety and efficacy of fasting regimens.
“Our epidemiologic studies do suggest that the standard religious practices of fasting (such as Ramadan fasting) that have been practiced for centuries and millenia are likely sufficient for the general population to obtain beneficial effects on the risk of chronic disease when a fasting regimen is used as a lifestyle over decades (rather than as a short-term weight-loss fad),” Horn says.
“For those who still develop risk factors for chronic disease, though, it may be that a more intense regimen of fasting is needed.”
Other contributors to this study are Jeffrey L. Anderson, J. Brent Muhlestein, and Amy Butler.