Phytotherapy Research | 2019
Herbal medicinal products and obesity: A PTR virtual issue
Abstract
According to the World Health Organization, overweight and obesity are defined as abnormal or excessive fat accumulation that presents a risk to health. Obesity represents a major health problem because it is associated with increased risk of diseases such as type 2 diabetes mellitus, cardiovascular diseases, and cancer (Blüher, 2019; Schetz et al., 2019). The prevalence of obesity has increased worldwide in the past years, with a prevalence from less than 1% in 1975 to 6– 8% in 2016, among girls and boys, and from 3% to 11% among men and from 6% to 15% among women (Jaacks et al., 2019). Data extracted from the National Health and Nutrition Examination Survey (2003–2004 to 2013–2014; n = 32,188) indicate that the estimated frequency of obesity increased by 20.4 million in the U.S. adults (Palmer & Toth, 2019). The treatment of overweight and obesity chiefly involves lifestyle changes and pharmacotherapy. Lifestyle and behavioral changes have limited effectiveness because complex hormonal and metabolic adaptive changes preserve weight loss and promote weight regain (Blüher, 2019). Furthermore, most medications cause limited weight loss and severe adverse effects that have caused a number of drugs to be withdrawn from the market in several countries (Rosa‐ Gonçalves & Majerowicz, 2019). Currently, six major FDA‐approved anti‐obesity drugs are available, that is, phentermine (a central stimulant), orlistat (a lipase inhibitor), phentermine/topiramate extended release, lorcaserin (a 5‐HT2c agonist), naltrexone sustained release (SR)/bupropion SR, and liraglutide (a glucagon‐like peptide‐1 receptor agonist, the only injectable formulation; Srivastava & Apovian, 2018). The rising rates of obesity in the world, the limited success of lifestyle changes, and pharmacotherapy—associated to the lack of compliance of the pharmacological treatment—drive many people towards the use of products invariably defined as nutraceuticals, dietary supplements, or herbal medicinal products (Andrew & Izzo, 2017; Farrington, Musgrave, & Byard, 2019; Ríos‐Hoyo & Gutiérrez‐ Salmeán, 2016). The popularity of such treatments for weight management has increased in the last years, and a wide variety of these products are available over the counter (Ríos‐Hoyo & Gutiérrez‐Salmeán, 2016). There is no clear clinical evidence that herbal products mostly promoted for weight loss, including Citrus aurantium, Garcinia cambogia, Camellia sinensis, Hoodia gordonii, and Coleus forskohlii preparations, can cause sustained long‐term weight loss (Farrington et al., 2019). Furthermore, serious adverse events and even death have been associated to their use (Farrington et al., 2019).