Purpose of Review <p>The ketogenic diet (KD) has gained clinical attention for its potential benefits in weight loss and metabolic syndrome. By mimicking fasting through carbohydrate (CHO) restriction, KD shifts energy utilization to ketone bodies (KB) instead of glucose. Despite promising results, the effects on different weight loss indicators remain controversial, with challenges in monitoring adherence standards, optimal macronutrient composition, potential risks, and long-term sustainability. This article aims to review the different weight-loss outcomes of KD interventions for obesity, monitored by KB (adherence indication).</p> Recent Findings <p>Current literature on KD interventions for obesity weight loss monitored by KB show reduction in different outcomes, including body weight, body mass index, waist circumference, visceral adipose tissue, fat mass, and body fat percentage. Minor decreases in lean body mass and skeletal muscle mass were noted without resistance training. Variability existed in adherence (KB markers), CHO intake (7–27% of daily energy), diet duration (28 days to 12 months), and follow-up frequency (weekly to biannual). KD, particularly accompanied by exercise, positively influenced appetite regulation.</p> Summary <p>KD interventions improves weight-related outcomes in participants with obesity but presents challenges in lean body mass reduction without resistance training and adherence variability. Standardizing methodologies, refining interventions and suitability to sub-populations, setting KB markers, and defining clinical relevance are essential for optimizing KD effectiveness.</p> Graphical Abstract <p>The physiological effect of KD</p> <p></p>