Zorba Paster: Time-restricted eating can aid your health

Study shows fasting could reduce A1c levels and help with weight loss

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A silhouetted runner enters the Schuylkill Banks Boardwalk on Thursday, Dec. 3, 2015, in Philadelphia. Matt Rourke/AP Photo

You may have heard about fasting for stronger, leaner bodies. It’s been talked about so much in the exercise community. It’s also viewed as a way to decrease your risk of diabetes, put on more muscle, give you more energy — all sorts of things.

Fasting isn’t new. It’s a common religious observance. Many Jewish people fast for Yom Kippur, their holiest day of the year, and Muslims do this for the month of Ramadan — fasting during the daytime while eating at night. It’s what you might call a partial fast.

But the question I have gotten time and time again on my radio show is this: Is fasting good for you?

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Well, a recent study published in the Journal of the American Medical Association shows that, yes, fasting just might be good for you, especially if you’re a Type 2 diabetic.

Researchers enrolled 500 people who were not on any medications for Type 2 diabetes — either had never been on diabetic medications or had not used them for the past three months. All were overweight and had hemoglobin A1c levels, a measurement of diabetic control, that were abnormal.

Under normal conditions, all of them would have been on medications to control their Type 2 diabetes.

The participants were divided into three groups. One group took metformin, the standard first drug we use for diabetes. One group took empagliflozin, sold under the brand name Jardiance — an expensive newer drug called an SGLT2-Inhibitor.  

The third group did a relative fast  using a 5:2 ratio. For five days, they ate normally. For two nonconsecutive days, they  almost totally fasted, eating only 500 calories from a predetermined package meal they were given. On the non-fasting days, they could eat what they wanted and as much as they wanted, but they were encouraged to follow a standard diabetic-type diet — fewer carbohydrates, regular meals, etc.

Everyone in the study met with a dietitian more than once to discuss how best to deal with their Type 2 diabetes.

At 16 weeks, here’s what happened — and it wasn’t exactly what the researchers expected.

First off, the hemoglobin A1c levels dropped in the two drug groups, those taking metformin and empagliflozin. That wasn’t surprising; it’s what these diabetic drugs do.

What was surprising was the A1c levels dropped in the fasting group, even more than in the diabetic med-taking group. That’s right, the group that fasted two days a week were in better control of their diabetes. The fasting group dropped nearly two points on this scale, while the drug groups dropped only 1.5 points — that was a statistically significant difference. 

Not only that, but the fasting group dropped more weight than the drug groups.

So let me put all of this into perspective. It’s a small study, only 500 people, so it’s worth repeating with a larger group. You can’t just take one study and make a conclusive decision. On the other hand, you can look at this study and see a pattern.

Next off, the results were measured at only four months. You could argue this would not hold up over several years, which may be a good point and something to consider further.

My spin: Despite the small study size and remaining questions, this is something we physicians and dietitians should think about when treating a new diabetic.

Some people will say, undoubtedly, “Give me the pill.” They’re not interested in fasting, and it doesn’t fit their lifestyle.

But others, especially diabetics interested in trying new things, just might say, “Hey, doc, I’d like to try this lifestyle change and see if I can control my blood sugar naturally.” Fasting might be for them.

If you’re a diabetic on medications, especially only one medication, and your A1c was just over the upper limit but not super high (the criteria for this study was 7 percent to 9 percent), you might want to try this. If you do decide to try fasting, talk to your health care provider first and get their take.

And let’s not forget that exercise plays a key role in managing diabetes. It’s not just what you put in your mouth but also how you take care of your diabetes overall that matters. Stay well.

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