In a relatively small randomized, crossover, controlled trial, time-restricted eating (also known as intermittent fasting) did not lead to improvements in weight or other selected health parameters compared to participants’ regular eating patterns. For four weeks, the 12 women and five men (average age of 26 years) with overweight or obesity ate whatever they wanted from 7:00 am to 3:00 pm and fasted the rest of the day. For another four weeks, they ate as they wanted.
The researchers measured body weight, waist and hip circumference, body composition, and blood pressure, and did blood tests to measure fasting blood glucose, cholesterol, triglyceride, and insulin concentrations. They also asked the participants to rate their hunger.
Overall, the researchers found no significant changes in body weight or other parameters, however, when analyzed separately, the women did lose some weight (about two pounds) during the intervention.
Some studies have reported benefits of time-restricted eating on weight, blood sugar control, blood triglyceride levels, and appetite, but others (like this study) have not. There are a lot of variables to consider when conducting research like this (including age, weight, and health of participants, the length of the study, and the length and timing of the fasting period). Currently, it appears that time-restricted eating patterns are pretty much equivalent to traditional caloric restriction for weight and health. Some people may find the approach helpful, while others may not. As with most approaches to achieve your health goals, find something that’s right for you.