World Obesity day was commemorated on 4 March this year. As more is understood about obesity as a disease, additional factors that affect obesity are coming into the spotlight.
Obesity is classified as a medical condition whereby a person carries excess weight or body fat that might negatively affect their health, and can be affected by a variety of factors including an abundance of food, a lack of physical activity and genetic susceptibility, according to the World Obesity Federation. Obesity is not solely affected by diet and a sedentary lifestyle as it is a complex medical condition impacted by a multitude of factors, including hormones. Different hormones play different roles One area of research into treating obesity focuses on hormones and the role it plays in appetite, hunger, weight loss and weight regain. Several hormones are responsible for appetite and satiety and could have an impact on weight and weight loss. When it comes to eating, ghrelin is the ‘hunger hormone’ and is called such because it sends signals to the brain that you are hungry when your stomach is empty. Ghrelin increases before eating and is often at the lowest an hour after eating, however studies have shown that ghrelin levels in people with obesity do not lower enough after eating, meaning the brain does not get a strong enough signal to stop eating and can lead to overeating. Leptin is a hormone that controls satiety or fullness levels by signalling to the brain that there is enough fat in storage and no more food is needed, which helps prevents overeating. When leptin signalling is impaired, the brain does not get the message to stop eating so it does not realise enough fat is stored and continues to push the drive to eat. Also, when you lose weight, leptin levels decrease making your brain think you are starving and pushing you to eat more. Glucagon-like peptide-1 (GLP-1) is another important satiety hormone produced in the gut when nutrients enter the intestines. GLP-1 plays an important role in regulating appetite by making you feel full during and between meals, as well as by slowly emptying your stomach, which may help you feel full for longer. This appetite regulation and stomach emptying slowing functions are thought to be responsible for the weight lowering effect of GLP-1. These hormones all occur naturally and are often imbalanced for people living with obesity and could require medical intervention. Tackling hormones to treat obesity Understanding how hormones impact weight by affecting hunger and satiety, and subsequently targeting the functions of these hormones, is one avenue of research into treating obesity. GLP-1 is one hormone that has been the focus of studies on how it affects weight and weight loss.
Studies have found that the weight loss effects of natural GLP-1 are not significant enough to have a clinical impact on weight loss.Despite remaining in circulation for several hours after eating, GLP-1 has a short half-life, meaning it is only effective for a few minutes. There is medication that is a derivative of GLP-1 that is 97% similar to the hormone, and has been created to overcome the short half-life and limited pharmacokinetic effects of naturally occurring GLP-1. Five large-scale randomised trials have been conducted to evaluate the efficacy of this medication as a weight loss intervention, and found that when used in conjunction with an exercise and eating plan, the medication is effective in assisting with weight loss and maintenance. One study found that over 80% of the participants on the medication maintained their weight loss in comparison to the participants on the placebo. This shows that the medication could be useful in maintaining weight loss in patients who are able to lose significant weight when making lifestyle changes. It is important to understand how hormones impact weight and why the fight against obesity might need more research, different approaches and medical intervention. Truth About Weight website
Novo Nordisk has launched the Truth About Weight website to assist people living with obesity. The website has detailed information on the many factors that can impact obesity, from hormones and genetics to stress and psychology, as well as detailing how to start a discussion about obesity and weight. For more information on obesity management, speak to your doctor or pharmacist today or visit Truth About Weight for more information on starting your weight loss journey.
Author: Tranica Gurcharan
References:
Yvette Brazier/Medical News Today: What is obesity and what causes it? Medical News Today; 18 November 2018. [Online]. Available from: https://www.medicalnewstoday.com/articles/323551 [Accessed 15 December 2020].
World Obesity Federation: Obesity is a disease: Our statement. [Online]. World Obesity Federation; May 2019. Available from: http://s3-eu-west-1.amazonaws.com/wof-files/NCD18_Useful_Information_.pdf. [Accessed 14 December 2020].
Healthline/Frankie Sprizler. 9 Proven Ways to Fix The Hormones That Control Your Weight. [Online]. Healthline; 7 March 2016. Available from: https://www.healthline.com/nutrition/9-fixes-for-weight-hormones#TOC_TITLE_HDR_4 [Accessed 15 December 2020]
Mehta, A., Marso, S. P., & Neeland, I. J. (2017). Liraglutide for weight management: a critical review of the evidence. [Online] Obesity science & practice, 3(1), 3–14. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5358074/ [Accessed 14 December 2020]