A randomized controlled trial recently published in The Journal of Nutrition found that intermittent calorie restriction and continuous calorie restriction were equally effective in promoting weight loss, with no significant differences in outcomes. Forty-six healthy women between the ages of 18 and 55 living in the U.K. who had overweight or obesity (BMI 25 or greater) were randomized to follow either a diet that cut daily energy intake by 25 percent or one that alternated days of regular calorie consumption with “fasting” days on which calories were reduced by 75 percent. Thirty women achieved at least 5 percent weight loss within 12 weeks, regardless of which approach they used to limit caloric intake.
Some studies have suggested that intermittent calorie restriction may be less likely than continuous calorie restriction to lead to hunger and muscle loss, but this study showed that neither approach led to these undesirable outcomes.
Restricting overall calorie intake leads to weight loss no matter how it is done. People looking to lose weight should follow a healthy dietary pattern that deceases total calorie intake in whatever way works best for them.