The high prevalence of overweight and obesity is an urgent public healthcare issue. It is primarily due to overweight, obesity, and related conditions that have a negative impact on quality of life, patients’ ability to work, morbidity and mortality, and result in high costs to the healthcare system. The simplest ways to determine the presence and severity of obesity are the patient interview and anthropometric measurements, including body weight, height, body mass index (BMI), waist circumference, hip circumference, and their ratios. However, this approach often does not provide information on the amount of body fat, its distribution patterns, the amount of skeletal muscle, and fat-free body mass, which can be important in determining the management and follow-up tactics. Therefore, various techniques have been proposed for assessing body composition, having their benefits and pitfalls. This review focuses on the bioimpedance analysis of human body composition as the simplest, noninvasive, and accessible method.