Intermittent fasting (IF) might sound like the latest weight-loss trend—and it is. But emerging research reveals that restricting eating can also help treat everything from high blood pressure to aging. Here, Dr. Christine Maren, a Broomfield-based functional medicine physician, helps us translate a few promising IF studies into easily digestible takeaways.
Researchers, including a neuro-scientist from Johns Hopkins University, released a study in 2017 indicating that IF can counteract and improve outcomes for a spectrum of age-related disorders, including diabetes, cardiovascular disease, and cancers, as well as neurological disorders such as Alzheimer’s and Parkinson’s diseases. The theory is that IF essentially mitigates the effects of getting older by bolstering the health of mitochondria (the power plants, or energy sources, of cells), DNA’s ability to repair itself, and autophagy (the process the body uses to flush out damaged cells to make space for new, healthier ones).
Eat Early, Eat Seldom
For about a decade, scientists have known that IF results in better overall health. But they didn’t know if those health benefits were a direct result of fasting or a byproduct of weight loss. So, for a 2018 study published in Cell Metabolism, researchers plied prediabetic men with enough calories to ensure they didn’t lose weight—and found that IF still improved insulin levels, insulin sensitivity, immune response, blood pressure, and oxidative stress. The catch? The results were only present in practitioners of early time-restricted feeding. In this study, that meant patients ate from 8 a.m. to 2 p.m. and fasted for the next 18 hours. Mysteriously, shifting the intake period to after 4 p.m. has either no effect on health or seems to worsen it.
Suzanne Devkota, an assistant professor of gastroenterology who has a lab named after her at Cedars-Sinai Medical Center, is leading ongoing research into the impacts of IF on the gastrointestinal tract and gut microbiome—all of the viruses, bacteria, protazoa, and fungi that take up residence in our bodies. People who regularly partake of a high-fat diet can suffer barrier disruption in the gut (essentially, bacteria can escape from the gastrointestinal tract into other parts of the body), causing inflammation that over the years can result in a prediabetic state. IF suppresses the bloom of harmful bacteria and promotes growth of bacteria that reinforce the barrier, according to Devkota’s research.
Try It At Home
Intermittent fasting, three ways.*
1. Time-restricted feeding
For every 24-hour cycle, eat only during a designated time period.
2. Alternate-day fasting
On Monday, Wednesday, and Friday, consume only one meal that equates to 25 percent of your normal daily caloric intake. Eat normally on the other days.
3. 5:2 fasting
During a week, fast (some people incorporate a 400- to 500-calorie diet on their fast days) on two nonconsecutive days and eat normally on the others.
*A few caution flags from Maren: Most women should stick to time-restricted feeding, as whole-day fasting is tough on their hormones. Maren also doesn’t recommend fasting for pregnant women and those trying to conceive. People with hypoglycemia or people on medication to lower blood sugar should also avoid IF.