Intermittent fasting topped 2019’s most-searched diets online. It’s in apps, books, blogs and articles. The diet confines eating to a shorter time frame during the day, typically followed by fasting for 16 hours.
Variations include eating windows of 6, 8 or 10 hours before fasting. Sometimes, it’s twice-weekly fasting for 24 hours. Popularity aside, scientific data is growing on intermittent fasting for certain health benefits, including for Type 2 diabetes and metabolic syndrome, said a Spokane professor.
“I’m hearing more talk about intermittent fasting at the American Diabetes Association’s scientific sessions,” said John White, a pharmacotherapy chairman at Washington State University’s College of Pharmacy and Pharmaceutical Sciences.
Studying diabetes care more than 30 years, he authored ADA’s “Medications for the Treatment of Diabetes.” Since 2017, he’s noticed more research on intermittent fasting as a medical approach.
One is a small 2018 study led by Dr. Jason Fung, a Canadian kidney specialist, author and researcher on intermittent fasting. It showed that three Type 2 diabetes patients got off insulin under medically supervised intermittent fasting and low-carb meals.
White said diabetes patients should work with a doctor before any diet changes, but evidence is mounting about how intermittent fasting improves insulin resistance. It’s especially beneficial if processed sugar and carbohydrates are restricted.
That doesn’t include healthy vegetables with fiber but rather other carbs and processed foods. “The problem of obesity and Type 2 diabetes – not all cases but generally – is related to diet,” White said.
“To a large degree, the culprit is processed sugar, which incidentally is found in about 70% of processed foods, but sort of hand-in-glove with that is this notion of intermittent fasting, or fasting, as a therapeutic modality.
“Metabolically, it undoubtedly causes a shift in insulin resistance, which is one of the primary defects in Type 2 diabetes. It’s powerful in allowing people sometimes to come off insulin and other meds. There are some other benefits; it might cause the body to sort of cleanse itself.”
How do longer breaks from eating help? White said typically you’re consuming fewer calories overall. Also, fasting gives the pancreas and digestive system a break.
The more processed sugar and carbohydrates consumed, the more insulin the body secretes. Over time, that excess causes the body to respond by reducing its sensitivity to insulin, White said.
Reduced insulin sensitivity causes more insulin to be secreted, he added, resulting in “higher and higher insulin levels and less and less sensitivity.” This duality is “highly related” to poor health conditions from obesity, such as cardiovascular disease and Type 2 diabetes.
Aging doesn’t help, nor does a high-calorie, high-carbohydrate diet, he said. Insulin also is a driver for deposition of fat. “It tends to be when you eat refined sugar, the fructose component goes to the liver, and, under the influence of insulin, it causes fat storage.”
Fasting as lifestyle
Spokane radio Shine 104.9 host Don Godman, 49, consulted with his doctor before starting intermittent fasting in April. With slow changes, he lost 82 pounds and now weighs 268.
At 6-foot-7-inches, he’s never been diabetic, but his doctor tested his blood glucose level beforehand. It was higher than preferred for being healthy.
“It wasn’t terrible, but my blood sugar was high, and I wasn’t feeling great,” Godman said. “I decided I needed to make a significant change that was different.
“I didn’t like how I felt, how I looked. Part of my story is the spiritual aspect, too. For me, it was kind of a conversation with God. I can’t do this; you’re going to have to change me.”
Godman previously tried other diets with a yo-yo effect. His physician does intermittent fasting and explained its science, he said. More determined, Godman decided to try it for a day.
“I thought, ‘I’m going to push breakfast back a little later, hold off on sugary stuff and see how it goes.’ ”
Slowly, he expanded the time frame for fasting, tracking non-eating periods on the Zero app and then daily calories on the Fitness Pal app. Godman also prepped high-protein, low-carb meals to freeze in containers for meals at work.
Before long, Godman said he wasn’t as hungry, and cravings lessened. He drinks a lot of water and restricts sugary treats to avoid large insulin spikes. Godman said the eating style helps burn more fat.
At first, he stopped eating by 7 p.m., then ate about 11 a.m. the next day. He traded encouragement with a co-worker who also did intermittent fasting, and they began regularly walking.
Godman now completes dinner typically by 5 p.m. before fasting. He doesn’t eat pie or other treats regularly but does indulge occasionally.
“I look at something like that and think, ‘No, I’ll pass this time.’ Since that pressure’s off, I’m fine. There will be another time. Now my blood work is the proof in the pudding. I just had blood work done.”
His highest blood glucose measurement was 105 mg/dL. Recently, it was at 85 mg/dL. “The doctor said that’s right where it should be.”
Godman said he’s happier with his health. “I feel better. I can move better. It’s amazing how much 80 pounds really is.”
Intermittent fasting can have benefits but also potential pitfalls, said Amy Yeoman, a Spokane dietician. She runs a company, Fuel to Thrive.
“It can definitely be a tool for weight loss, but I would be hesitant with diabetics just because their blood sugar levels need to be monitored so carefully,” Yeoman said. “It definitely would have to be done under close medical supervision.”
Generally, she said healthy people can see benefits, but it isn’t a cure-all. “I think people who are successful on it are those who feel like they need more control in their eating,” said Yeoman, including boundaries to stop eating.
Yoeman cautions about the possibility of feeling so hungry in a fasted state that you might overeat when fasting ends, “Which takes away the effects of it.” For regular fitness, intermittent fasting can be tricky regarding energy for workouts, she said.
“Most people who are working out and doing this say it’s a lot harder. You can’t get quite the same intensity because you don’t have any carbohydrates to burn off of,” she said. “I’m not a huge fan of supplements, but I’ll encourage a branched-chain amino acid drink right before.
“In fasting terms, that doesn’t break the fast, but it gives your body some protection against using its muscle for energy.”
In a fasted state, the body’s glycogen (carbohydrates) have been used up, Yeoman said. Without carbohydrates or in a fasted state, the body will use gluconeogenesis, protein from muscle broken down, and lipolysis, fat broken down, to get energy.
“During rest, fat tissue is easier to utilize, but, as your heart rate increases, it becomes harder.”
White also acknowledged that each person has a different physiology, so a diet that works for one might not for another. But he sees a trend in medicine of “deprescribing” as health professionals work to reduce medications through lifestyle and diet changes.
Under the Fung study, the patients ate only dinner on fasting days while during nonfasting days, they ate lunch and dinner focused on low-carb foods. All reported feeling good and lost weight. Two patients ended diabetic medications entirely while the third one weaned off three of four medications.
A separate study published in Cell Metabolism found 19 participants with metabolic syndrome lost weight and reduced their waist circumference with intermittent fasting. They also saw lowered cholesterol and blood pressure in a three-month period.
“Fasting has been around for thousands of years,” White said. “There are components of fasting in probably every major religion, which doesn’t make it good or correct, but it’s interesting to consider.
“If you just look at the data, it strongly suggests that some type of fasting, whether 16 hours a day periodically or an occasional 24-hour fast, is probably really good for you.”