Reducing food caloric density may help with weight loss and maintenance.  

It seems like a no-brainer but energy density may enhance weight loss or gain depending on which side of the spectrum it lies on and the dieter’s own genetics and metabolism.  All diet plans are different I am certain that not all diets that concentrate on low or high energy density are the same.  In fact, I would guess that not only are they not the same, but they also are not even comparable.  It is unclear whether all dietary strategies that reduce ED are comparable, hindering effective ED guidelines for obesity treatment. This study examined how changes in

A 2017 study looked at this very question​[1]​.   The study examined how changes in the number of low-energy-dense and high-energy-dense foods consumed affected dietary weight loss within an 18-month weight-loss trial.  The belief is that if you consume calorically dense foods you will be pro likely to gain weight.  The researchers examined data from 183 participants randomized to an energy-restricted lifestyle intervention or lifestyle intervention plus limited non-nutrient energy-dense food.  The number of daily low-energy-dense and high-energy-dense foods consumed was calculated from three, 24-hr dietary recalls, and anthropometrics were measured at 0, 6, and 18-months.  The anthropometric measurements included ED, BMI, and percent weight loss.  The researchers found an increasing number of LED foods consumed was associated with 6- and 18-month reductions in BMI, but participants consuming ⩽2 high-energy-dense foods/day and ⩾6.6 low-energy-dense foods/day experienced better weight loss outcomes at 6- and 18-month than participants only consuming ⩽2 high-energy-dense foods/day.  Translated, reducing highly dense foods in calories is only effective if you also increase the lower dense foods also.  This makes sense because you still need to induce satiety and if you reduce food intake, you will be hungry unless you replace it with something.  

The bottom line: An increasing number of low-energy-dense foods is associated with weight loss. It is unclear whether all dietary strategies that reduce energy density are effective for obesity treatment. Reducing dietary ED may differentially influence weight-loss trajectories, but further randomized controlled trials are needed.