Use of GLP-1 medications for weight loss is accelerating rapidly with Mounjaro & Wegovy now household names. Are these drugs a panacea for the obesity epidemic, or do the wide-ranging side effects make them a healthcare time bomb? Let’s take a close look at the ‘GLP-1 receptor agonists’ – how they work, what the side effects are, and how we can help, as well as natural alternatives.
The rise in repurposed GLP-1 medications used for weight loss is creating ripples through the world as pharma companies rake in profits, while processed food companies quake in their boots at potential lost revenue. It’s no exaggeration to say that they could be game-changing in many ways in the next 10 years both in terms of the dramatic effects they have on health, for good or ill, but also the economic and cultural challenges they may pose.
Are these drugs a panacea for the obesity epidemic, or do the wide-ranging side effects make them a healthcare time bomb? One thing’s for sure, they are here to stay, and their use is likely to increase dramatically, so, as practitioners, how do we manage people choosing to lose weight in this way, and could it even be a positive opportunity? Let’s take a close look at the ‘GLP-1 receptor agonists’ – how they work, what the side effects are, and how we can help, as well as natural alternatives.
Why are obesity levels increasing?
First up, what’s the problem these drugs are trying to solve? It’s one that practitioners have been dealing with for decades as metabolic dysfunction, including obesity, increase exponentially worldwide, with a sobering 64% estimated as overweight or obese in the UK.[1] Of course this is not simply a question of ‘calories in, calories out’. It does seem that there are certain people who are more susceptible to weight gain than others. Individual factors in metabolism or appetite regulation therefore play a significant part, and we now have a better understanding that overweight people are not simply ‘lazy’ and ‘greedy’.
However, the major driver has been the mass commoditisation of food in the form of ready-made processed food that has accelerated the problem in the last 50 years. Generally, people are eating more frequently and living on a diet of high fat/carb fast processed food and drink. Also, many use food as a stimulant, and our food preferences can easily form part of our everyday addictive behaviours. In a different world, fewer people would have their genetic susceptibilities exposed, but in this new world, more people find it difficult to control their weight.
How do GLP-1 medications work?
As we digest and metabolise food for energy, GLP-1 (glucagon-like peptide-1) is secreted by gut cells and acts as a regulator for metabolism. Blood glucose levels begin to rise, and GLP-1 signals that we are sated and have sufficient ‘potential energy’ to work on and use up, so it starts to wind down certain key processes. Digestive processes are generally downregulated, essentially to reduce the supply of more ‘digested energy’. Gastric emptying is inhibited, promoting a feeling of fullness, and, mostly as a result, production of HCl, pancreatic enzymes, bile production, and gut motility are all reduced. [2] [3] [4] [5]
At the same time, GLP-1 directly downregulates appetite via the nervous system. It increases activity of POMC neurons (part of the leptin-melanocortin system of appetite suppression in the hypothalamus) and dampens the opposing hunger system involving ghrelin, AgRP and NPY, promoting increased satiety.[6] This mechanism promotes the dramatic reduction in ‘food noise’ people using GLP-1 medications report.
GLP-1 also increases the secretion and action of insulin, enhancing cellular uptake for energy production. Coupled with the delayed digestion and absorption of carbohydrates, this can help improve insulin function and sensitivity.[7] It also promotes lipolysis indirectly, so breaking down stored fats for energy and increases adiponectin.[8] Some research even suggests that GLP-1 suppresses inflammation via reduced inflammasome activity, and reduces oxidative stress.[9] Taken together, these effects are also protective of cardiovascular health in multiple ways.
The relationship between GLP-1 and wider nervous system effects is complex and controversial. GLP-1 seems to directly affect dopamine and serotonin pathways, and mostly people report a reduction in certain addictive behaviours, including alcohol and drug use, and an overall reduction in depression and improved mood.[10]
As a powerful hormone, GLP-1 came under the spotlight some 20 years ago with the introduction of the first GLP-1 mimicking drugs for diabetes. When it became obvious that the patients using them were losing weight, the pharma industry saw an opportunity and quickly began to repurpose them for weight loss. This has led to the modern explosion where we now have millions of people paying privately for ‘GLP-1’ weight loss injections like Ozempic, Wegovy, and Mounjaro.[11] The results are dramatic, with many experiencing fast and significant weight loss. The latest medication, Mounjaro also includes a GIP (glucose-dependent insulinotropic polypeptide) receptor agonist which has some additional effects including promoting glucagon, to speed up fat burning.
But there is big difference between the generally positive effects of natural GLP-1 hormone produced by our bodies in sync with our daily activity, and a weekly high dose injection of a synthetic version, essentially tricking the body, into an artificial ‘GLP-high’. We couldn’t possibly expect to do that and gain benefits without significant risks, could we..?
What are the side effects of GLP-1 medications?
While GLP-1 medications seem highly effective at reducing hunger and weight, they do not come without significant costs.
Inadequate nutrition
By artificially reducing food intake, there is a risk of insufficient nutrition of certain macronutrients (low protein and potential muscle loss) or micronutrients. Reduced stomach function increases risk of vitamin B12/mineral deficiency, inadequate protein digestion, and gastro-oesophageal reflux. Reduced digestive enzymes and bile may increase maldigestion, impacting levels of essential fats and fat-soluble nutrients (e.g. vitamin D).[12] There may then be further increased risk of developing osteoporosis, reduced methylation, fatigue, muscle loss and sarcopenia.[13]
Liver/gall bladder and pancreatic dysfunction
Reduced bile flow may increase blood fats, cholesterol, and risk of fatty liver/gallstones. Bile duct blockage may also result in acute pancreatitis.[14]
Other gut issues
Reduced gut motility also increases risk of an imbalanced microbiome, bloating and constipation. Increased length and villus height of the intestine may result in increased risk of intestinal obstruction.[15]
Mental health
While the evidence for many seems to be that mental health can be improved, the impact of GLP-1 medications on the nervous system are complex. Perhaps because of our individual pattern of response to changes in serotonin/dopamine systems, some experience increased anhedonia, depression, and even suicidal thoughts.[16]
Acclimatisation/rebound weight gain
GLP-1 receptor desensitisation means larger doses may be needed to maintain appetite suppression. Stopping GLP-1 medication is associated with a significant risk of rebound weight gain.[17] Using GLP-1 for weight loss could be a lifetime commitment with significant long-term side effects.
How can we naturally promote GLP-1 hormone?
As practitioners, it’s inevitable we are going to encounter clients using GLP-1 receptor agonist medications. We can and should explore alternative strategies of course, but we may also need to support our clients to use them as safely as possible. Consider investigating and supporting the following key areas:
Encourage dose reduction and microdosing
As with all medications, taking the bare minimum needed to support is preferable (‘micro-dosing’), along with diet and lifestyle approaches. There are multiple YouTube videos with users experimenting with personalised dosing, and the ‘private prescription’ mechanic lends itself to this. Ideally this is done with professional support.
Diet
Ensure eating less does not mean eating poorly. Eat nutrient dense foods, with adequate protein and fats, to help maintain energy and preserve muscle mass. Soluble fibre (‘prebiotics’) in a high vegetable diet naturally promotes GLP-1.[18] Consider adding in a good multivitamin, potentially with additional vitamin B12 and vitamin D.
Vitamin B12 Spray
Vitamin D3 & K2 Spray
Meal timing/sequencing
Don’t skip meals, and eat most food earlier in the day. Fast overnight from 8pm max or even earlier, prolong mealtimes with good chewing and consider eating protein and vegetables first in a meal to promote natural GLP-1 levels.
Regulate blood glucose levels/insulin
The right dietary balance as above will help this significantly, and consider blood glucose supporting supplements including chromium, cinnamon and magnesium. [19] [20] [21]
Exercise
Especially weight bearing to maintain muscle mass. Use the ‘opportunity’ to develop positive lifestyle habits. Consider additional energy support during exercise to maintain energy and increase muscle mass, including creatine and electrolytes.
Electrolyte & Creatine Complex
Support digestion/gut balance
Relaxed mealtimes, chewing food well and considering HCl, digestive enzymes and probiotics to support digestion and motility.
Liver support
To encourage detoxification and bile flow/gall bladder function including artichoke and choline.
Liver Health
Choline Bitartrate
An opportunity for change
The ‘miracle jabs’ are here to stay, creating a new audience who are potentially concerned about metabolic health, and now have a new entry point to dramatically change their diets and lifestyles. As practitioners we need to be equipped to support clients using them and guide them on their journey. This is an opportunity to seize, and in doing so, we can potentially support people to make huge changes that could really improve their metabolic health and reduce chronic disease risk.
References
[1] https://www.gov.uk/government/statistics/update-to-the-obesity-profile-on-fingertips/obesity-profile-short-statistical-commentary-may-2024
[2] Jalleh, R. J., et al. (2024). Clinical Consequences of Delayed Gastric Emptying With GLP-1 Receptor Agonists and Tirzepatide. The Journal of clinical endocrinology and metabolism, 110(1), 1–15.
[3] Wettergren, A., et al. (1998). Glucagon-like peptide-1 inhibits gastropancreatic function by inhibiting central parasympathetic outflow. The American journal of physiology, 275(5), G984–G992.
[4] Drucker DJ. (2018) Mechanisms of Action and Therapeutic Application of Glucagon-like Peptide-1. Cell Metab. Apr 3;27(4):740-756.
[5] He, L. et al. (2022). Association of Glucagon-Like Peptide-1 Receptor Agonist Use With Risk of Gallbladder and Biliary Diseases: A Systematic Review and Meta-analysis of Randomized Clinical Trials. JAMA internal medicine, 182(5), 513–519.
[6] Bucciarelli, L., et al. (2025). Psychotropic effects of GLP-1R agonists. Pharmacological research, 222, 108036.
[7] Chai, W., et al. (2014). Glucagon-like peptide 1 recruits muscle microvasculature and improves insulin’s metabolic action in the presence of insulin resistance. Diabetes, 63(8), 2788–2799.
[8] Liu Q. K. (2024). Mechanisms of action and therapeutic applications of GLP-1 and dual GIP/GLP-1 receptor agonists. Frontiers in endocrinology, 15, 1431292.
[9] Liu, C., et al. (2024). GLP-1R activation attenuates the progression of pulmonary fibrosis via disrupting NLRP3 inflammasome/PFKFB3-driven glycolysis interaction and histone lactylation. Journal of translational medicine, 22(1), 954
[10] Krupa A. J. (2025). Curbing the appetites and restoring the capacity for satisfaction: The impact of GLP-1 agonists on the reward circuitry. Neuroscience applied, 4, 105512.
[11] https://news.sky.com/story/ozempic-to-mounjaro-what-are-the-weight-loss-injections-and-what-were-they-designed-to-do-12823419#:~:text=An%20estimated%201.5%20million%20people,through%20specialist%20weight%20management%20services.
[12] Christensen, S., et al.(2024). Dietary intake by patients taking GLP-1 and dual GIP/GLP-1 receptor agonists: A narrative review and discussion of research needs. Obesity pillars, 11, 100121.
[13] Memel, Z., et al. (2025). Impact of GLP- 1 Receptor Agonist Therapy in Patients High Risk for Sarcopenia. Current nutrition reports, 14(1), 63.
[14] He L, Wang J, Ping F, et al. (2022) Association of glucagon-like peptide-1 receptor agonist use with risk of gallbladder and biliary diseases: a systematic review and meta-analysis of randomized clinical trials. JAMA Intern Med 2022; 182(5):513–519.inflammasome/PFKFB3-driven glycolysis interaction and histone lactylation. Journal of translational medicine, 22(1), 954.
[15] Lu, J. et al (2023). A potentially serious adverse effect of GLP-1 receptor agonists. Acta pharmaceutica Sinica. B, 13(5), 2291–2293.
[16] Krupa A. J. (2025). Curbing the appetites and restoring the capacity for satisfaction: The impact of GLP-1 agonists on the reward circuitry. Neuroscience applied, 4, 105512.
[17] Wu H, et al. (2025) Trajectory of the body weight after drug discontinuation in the treatment of anti-obesity medications. BMC Med. 22;23(1):398.
[18] Zhao, L., et al (2018). Gut bacteria selectively promoted by dietary fibres alleviate type 2 diabetes. Science (New York, N.Y.), 359(6380), 1151–1156.
[19] Khan A, et al. (2003) Cinnamon improves glucose and lipids of people with type 2 diabetes. Diabetes Care. 26(12):3215-8.
[20] Havel PJ. (2004) A scientific review: the role of chromium in insulin resistance. Diabetes Educ. Suppl:2-14
[21] Akimbekov NS, et al. (2024). The role of magnesium in pancreatic beta-cell function and homeostasis. Front Nutr. 11:1458700.
All of our blogs are written by our team of expert Nutritional Therapists. If you have questions regarding the topics that have been raised, or any other health matters, please do contact them using the details below:
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Last updated on 12th January 2026 by cytoffice
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