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Fiber comprising a lot of an overall healthy diet may have resulted in weight loss for two groups of people in a recent study- those who ate only during a shortened period while they were awake, so-called time restricted eating or TRE, and those who ate the same types of foods but in a more typical consumption pattern. Nisa Maruthur, the study’s lead investigator and a primary care physician at Johns Hopkins, comments.

Maruthur: One of the things that was interesting and I think this is true for people who end up on more plant based diets. Because it was healthy we're giving them a lot more fiber than they were used to. people who were assigned to TRE and having to eat 80% of their calories before 1:00 PM having like a fibrous meal that you weren't used to it was very difficult. I mean they did it but it was difficult. That was the thing I would hear at the beginning a lot, like there are too many blueberries how are you supposed to eat all those blueberries. For the volumetrics part of this was probably kind of difficult for people. It wasn't so difficult that we didn't end up with really high adherence.   :30

Maruthur says adding much more fiber to a diet helps quality as well as quantity. At Johns Hopkins, I’m Elizabeth Tracey.

Is there any benefit at all to time restricted eating, or TRE, for losing weight when compared to a usual eating pattern? That’s the question addressed in a recent Johns Hopkins study headed by Nisa Maruthur, a primary care expert, and colleagues.

Maruthur: We were looking at a weight change in both arms expecting the TRE arm to look more beneficial if TRE is beneficial for weight loss and basically there was no difference at 12 weeks. Both groups lost some weight which is why you’ve got to have a control group. They probably were eating fewer calories, less sodium, things like that because we were providing a healthy diet. Regardless of what they were eating at baseline we didn't see any effects of the TRE, the time restricted eating compared to the usual eating pattern on glucose measures either which were our secondary outcomes.  :28

Maruthur says the study provided participants with food, support and counseling to enable them to adhere to a healthy diet. Much more fiber comprised the diet in comparison to what participants were accustomed to eating, which may account for why everyone lost weight over the 12 week period. At Johns Hopkins, I’m Elizabeth Tracey.

If you’re thinking of using time restricted eating, where you only consume food for a shortened part of your waking hours, for weight loss, results of a new study from Johns Hopkins may inform. Nisa Maruthur, a primary care physician, and colleagues, rigorously investigated the strategy.

Maruthur: It's a controlled feeding study so we gave them all their food for the 12 weeks they ate on site three times a week we had them fill out a daily diary to kind of figure out what they're eating and there was a lot of coaching and intervention around helping them eat only our food and nothing else the other thing that was crucial for this study is we kept it isocaloric meaning we figured out how many calories you need a baseline and we gave you that number of calories so that was fixed if we figured out you need 2000 calories a day for weight maintenance then we gave you 2000 calories that was a big distinction from other studies we thought was really important for understanding the independent effective timing of feeding.                   :31

Results indicate that time restricted eating did not result in more weight loss or improve other aspects of someone’s overall health compared with a normal eating group. At Johns Hopkins, I’m Elizabeth Tracey.

Time restricted eating, or TRE, seems like it might help people lose weight, many studies in animal models suggested. So Nisa Maruthur, an internal medicine expert at Johns Hopkins, and colleagues designed a study to assess this strategy in people.

Maruthur: They were randomized either to time restricted eating or to a usual eating pattern for 12 weeks and the time restricted eating arm ate all their calories between 8:00 AM and six PM, 80% of them before 1:00 PM. We think the time restricted eating might be good and we think eating earlier in the day that lines up with your circadian rhythm might be good so that's what we were looking at in the TRE group, and in the usual eating pattern group we designed that to model more of what our typical eating patterns are. So more calories at the end of the day, fewer calories at the beginning and they could eat until midnight, but most of their calories were between 8:00 and 8:00.   :30

Maruthur says the disappointing result was that after 12 weeks there was essentially no difference between the TRE group and the usual eating group. Other outcomes in addition to weight also failed to show a benefit of TRE. Maruther says the best weight loss strategy for most will be one tailored to an individual’s needs and preferences. At Johns Hopkins, I’m Elizabeth Tracey.

Will restricting how many hours while you’re awake you allow yourself to eat help you lose weight? So called time restricted eating looked promising based on some studies, so Nisa Maruthur, an internal medicine expert at Johns Hopkins, and colleagues conducted a rigorous study on the strategy.

Maruthur: There was a gap in very few studies had looked at this. Very few in humans, very few had done a controlled feeding study and then very few had lasted for very long like more than a week or had more than like 10 people in it. So we just wanted to do something that would be as informative for evidence in humans as possible. So it still looks like the intervention that's going to be best for you is one you can follow and some people do find that some people eat fewer calories when they're time restricting. That could be beneficial but yeah we didn't find it was magical in itself.   :29

Maruthur notes that animal studies in particular provided dramatic results on the ability of time restricted eating, or TRE, to result in weight loss, but this study doesn’t bear out those results in people, although it may work for some. At Johns Hopkins, I’m Elizabeth Tracey.

Metformin is a older medication used for type 2 diabetes that’s now being evaluated for improving longevity. Another diabetes medicine called a GLP-1 agonist is being used to treat obesity. Diabetes expert Rita Kalyani at Johns Hopkins says possible expanded uses for these drugs extend to other classes as well.

Kalyani: Older classes of medications though too have indications or benefits outside just diabetes.For instance pioglitazone, which we've had for a long time, we know that there have been studies demonstrating benefit in reducing progression to diabetes, cardiovascular disease also on what we used to call non alcoholic liver disease. So I think it's important to recognize that what we're seeing with the newer classes of agents in terms of pleiotropic potential benefits is not singular to the newer classes of agents. I think it's a win win for all of us.      :32

Kalyani cautions that until the data is in, no one should be taking a diabetes drug for another purpose. At Johns Hopkins, I’m Elizabeth Tracey.