Overweight and obesity are the epidemics of the 21st century in developed countries. Obesity is associated with several metabolic disorders and various diseases such as type 2 diabetes, cardiovascular disease, high blood pressure, dyslipidemia (high levels of circulating triacylglycerols and low-density lipoprotein cholesterol, and low levels of high-density lipoprotein cholesterol), commonly referred to as Metabolic Syndrome (MS). Although there is a therapeutic arsenal to combat some of these diseases, especially type 2 diabetes and cardiovascular disease, both the intake of proper diets and maintaining healthy lifestyles are considered the best preventive measures. The general population has access to a variety of dietary foods for weight loss, and to nutritional supplements. It is important to identify those foods and supplements that are effective and safe. The purpose of this review is to examine, from a critical point of view, food components currently used by health professionals and by the general population as coadjuvants in the prevention of obesity.