Ketogenic Diets for Weight Loss Maintenance: Impact on Energy Expenditure and Appetite in Individuals With Obesity

Ketogenic Diets for Weight Loss Maintenance: Impact on Energy Expenditure and Appetite in Individuals With Obesity

The goal of this clinical trial is to investigate whether a Ketogenic Diet (KD) can increase Total Energy Expenditure (TEE), while benefiting appetite, during weight loss maintenance in reduced-obese individuals.

The total duration of the intervention will be 10 weeks. Participants will first undergo 4 weeks of a low-energy diet (LED), aiming to induce a minimum of 5% weight loss (weight loss phase). Those who achieve at least a 5% weight loss will then be randomized (1:1) to a 6-week weight loss maintenance (WLM) diet, either a KD or an isocaloric low-fat diet, with the first 2 weeks being a gradual refeeding.

Inclusion Criteria:

• BMI 30-45 kg/m2
• Both men and women
• Age between 18-65 years
• Sedentary to moderately active (<2 h/wk of moderate, structured, intentional, exercise)

Exclusion Criteria:

• Pregnancy or lactation
• Daily use of tobacco (>1 pk/wk)
• Change in weight greater than 5 lb in the previous 3 months
• Cognitive impairment
• Previous bariatric surgery
• History of eating disorder
• Presence of any condition (e.g. DM2, PCOS, inflammatory disease, untreated thyroid disease, fluid overload states such as chronic kidney disease, congestive heart failure, or cirrhosis)
• Use of any medication (e.g., glucocorticoid, GLP-1 analogues, hormone replacement therapy) deemed to interfere with study outcomes.
• Pre-menopausal women will need to have a regular menstrual cycle (28+/-2 days) or be on hormonal contraceptives
• Fasting glucose plasma concentration >125 mg/dl and/or HbA1c > 6.4%