Table 1. A list of studies selected and included in this systematic review.

A table indicating the list of studies included in this systematic review, showing the authors' names, study titles, study objectives, study design, sample size, and study findings.

Author	Study	Study Objectives	Design	Sample Size	Main findings
Hannon et al. [50]	Lower energy-dense ready meal consumption affects self-reported appetite ratings with no effect on subsequent food intake in women.	To compare commercially available equicaloric ready meals differing in energy density on satiety and food intake.	Randomized Control crossover study	Twenty-six female participants aged 18-65 years; body mass index of 28.8 ± 3.0 kg/m2	The participants felt more satiated after consuming ready meals of the same energy content but larger portion size. Despite no significant difference in short-term EI between the ready meals, the results indicated that the LEDRM produced beneficial subjective satiety responses and, therefore, can help to improve the nutritional content of meals i.e., reduce saturated fat consumption.
Bottone et al. [52]	Obese older adults report high satisfaction and positive experiences with care.	To examine the independent impact of obesity on patient satisfaction and experiences with care in adults 65 years of age and older with Medigap insurance.	Mixed method research	Fifty-three thousand two hundred and eighty six randomly chosen adults with an AARP Medicare Supplement Insurance Plan	Relative to normal weight, obesity was significantly associated with higher patient satisfaction and better experiences with care in seven of the eight ratings measured.
Champagne et al. [56]	Fiber intake, dietary energy density, and diet-type predict 6-month weight-loss in free-living adults who adhered to prescribed macronutrient and energy composition of varying diets.	To identify predictors of weight loss after six months in participants who adhered to energy and macronutrient assignments.	Mixed methods research	Three hundred and forty-five participants	The decrease in energy density was positively associated with weight change for each diet-type; however, this effect was most profound in the high-fat, average-protein diet, suggesting that dietary factors may positively influence weight loss in addition to energy intake and macronutrient composition.
Fung et al. [57]	Low-carbohydrate diets and all-cause and cause-specific mortality: two cohort studies.	To provide a mechanistic paradigm for future research in the area of ACM.	Prospective cohort study	Eighty-five thousand three hundred and sixty-eight women (aged 34-59 years at baseline) and 44,548 men (aged 40-75 years at baseline) without heart disease, cancer, or diabetes.	To examine the association of low-carbohydrate diets with mortality during 26 years of follow-up in women and 20 years in men.
Lowe et al. [62]	Meal replacements, reduced energy density eating, and weight loss maintenance in primary care patients: a randomized controlled trial.	To compare the absence of presence of meal replacements (MRs) alongside energy density (ED) intervention in facilitating maintenance of weight loss.	Mixed method research	Two hundred and thirty-eight overweight patients with mean BMI = 39.5 kg/m2	Each group with the exception of ED+/MR- regained substantial weight during the follow-up, while the ED+/MR- group was observed to have regained significantly less weight compared to the control group during follow-up assessments.
Flood et al. [64]	The effects of beverage type and portion size on beverage consumption and lunch intake.	To examine the impact of increasing beverage portion size on beverage and food intake.	Crossover design	Thirty-three subjects	Increasing beverage portion size significantly increased the weight of beverage consumed, regardless of the type of beverage served (P < 0.05). As a consequence, for the caloric beverage, energy intake from the beverage increased by 10% for women and 26% for men when there was a 50% increase in the portion served (P < 0.01).
Sacks et al. [67]	Comparison of weight-loss diets with different compositions of fat, protein, and carbohydrates.	To assess the possible advantage for weight loss of a diet that emphasizes protein, fat, or carbohydrates	Randomized control trial	Eight hundred and eleven overweight adults.	Reduced-calorie diets result in clinically meaningful weight loss regardless of which macronutrients they emphasize.
Shai et al. [68]	Weight loss with a low-carbohydrate, Mediterranean, or low-fat diet	To compare the effectiveness and safety of three nutritional protocols: a low-fat, restricted-calorie diet; a Mediterranean, restricted-calorie diet; and a low-carbohydrate, non–restricted-calorie diet.	Dietary Intervention Randomized Controlled Trial (DIRECT)	Three hundred and twenty-two moderately obese participants	Mediterranean and low-carbohydrate diets may be effective alternatives to low-fat diets. The more favorable effects on lipids (with the low-carbohydrate diet) and on glycemic control (with the Mediterranean diet) suggest that personal preferences and metabolic considerations might inform individualized tailoring of dietary interventions.
Gardner et al. [69]	Effect of Low-Fat vs Low-Carbohydrate Diet on 12-Month Weight Loss in Overweight Adults and the Association With Genotype Pattern or Insulin Secretion: The DIETFITS Randomized Clinical Trial.	To determine the effect of a healthy low-fat (HLF) diet vs a healthy low-carbohydrate (HLC) diet on weight change and if genotype pattern or insulin secretion are related to the dietary effects on weight loss.	Diet Intervention Examining The Factors Interacting with Treatment Success (DIETFITS) randomized clinical trial	Six hundred and nine adult participants aged 18 to 50 years with a BMI of between 28 and 40.	There was no significant difference in weight change between a healthy low-fat diet vs a healthy low-carbohydrate diet, and neither genotype pattern nor baseline insulin secretion was associated with the dietary effects on weight loss.
Jenkins et al. [70]	The effect of a plant-based low-carbohydrate (“Eco-Atkins”) diet on body weight and blood lipid concentrations in hyperlipidemic subjects	To examine the effect of a plant-based low-carbohydrate ("Eco-Atkins") diet on body weight and blood lipid concentrations in hyperlipidemic subjects.	Randomized controlled trial	Hyperlipidemic subjects	The plant-based low-carbohydrate ("Eco-Atkins") diet resulted in significant reductions in body weight and improvements in blood lipid concentrations, particularly a decrease in LDL cholesterol and triglycerides. HDL cholesterol levels remained stable or slightly increased.
Esposito et al. [72]	Mediterranean diet and weight loss: Meta-analysis of randomized controlled trials.	To assess the effects of Mediterranean diets on weight loss and obesity management	Meta-analysis of randomized controlled trials.	Three thousand four hundred and thirty-six participants (1,848 assigned to a Mediterranean diet and 1,588 assigned to a control diet)	The effect of Mediterranean diet on body weight was greater in association with energy restriction (mean difference, -3.88 kg, -6.54 to -1.21 kg), increased physical activity (-4.01 kg, -5.79 to -2.23 kg), and follow up longer than six months (-2.69 kg, -3.99 to -1.38 kg).
Willett and Leibel [80]	Dietary fat is not a major determinant of body fat.	To evaluate the effect of dietary fat on adiposity	Randomized controlled trials	Two hundred and four participants	In the short-term, modest reductions in body weight are typically seen in individuals randomized to diets with a lower percentage of calories from fat.