Why It’s Too Soon to Recommend Intermittent Fasting to Treat Type 2 Diabetes
One of the reasons intermittent fasting is so controversial is that there are limited large-scale human studies that prove it’s safe and effective in humans long term, says Robert Gabbay, MD, PhD, chief medical officer at Joslin Diabetes Center at Harvard Medical School in Boston.
One such study, published in July 2018 in the Journal of the American Medical Association, found that intermittent fasting was no better at improving type 2 diabetes participants’ blood sugar levels than regular caloric restriction after one year. Previous studies on mice suggest intermittent fasting may improve memory, reduce disease risk, and aid with weight loss, according to an article published in June 2013 in the journal CMAJ, but, as Dr. Gabbay points out, “That doesn’t always translate to people.”
Yet Gabbay says preliminary human studies with positive results, like this week’s in BMJ Case Reports, suggest the diet is worthy of further study in a larger population over a longer period of time. For now, he cautions people with diabetes, especially those on insulin and sulfonylureas to lower their blood sugar, against trying intermittent fasting before speaking with their healthcare provider.
Fung agrees, saying medical supervision is key when fasting and managing diabetes. “If you’re on medication, you have to talk to your doctor because they’re the ones who are going to guide you. We were the ones who guided these patients,” Fung says.
A Look Ahead at Possible Intermittent Fasting Research
Because of the small size of the current study and the potential health risks of intermittent fasting (high and low blood sugar, among them), Gabbay says it’s too soon to officially recommend intermittent fasting for diabetes treatment. He is also skeptical about the sustainability of intermittent fasting.