GLP-1 analogs
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GLP-1 analogues are medications that mimic the action of glucagon-like peptide-1, an intestinal hormone involved in the regulation of glycemia, appetite, and gastric emptying. They include, among others, liraglutide, semaglutide, and dulaglutide. The same broadly defined group of incretin therapies also includes multi-receptor agonists, such as tirzepatide, which acts on GIP and GLP-1 receptors. These preparations are primarily used in the treatment of type 2 diabetes, and selected ones also in the pharmacotherapy of obesity and overweight with coexisting complications. They are neither supplements nor a method for cosmetic weight loss. They are prescription medications requiring medical qualification, gradual dose escalation, and monitoring of efficacy, tolerability, and the patient's nutritional status.
GLP-1 analogs - what are they
GLP-1, or glucagon-like peptide-1, is an incretin hormone secreted mainly by the L cells of the small and large intestine after food ingestion. It is formed from proglucagon and acts through a specific GLP-1R receptor belonging to the G-protein-coupled receptor family. These receptors are located, among others, in the pancreas, gastrointestinal tract, and central nervous system.
GLP-1 analogues, more precisely defined as GLP-1 receptor agonists, activate the same receptor but have been modified to act significantly longer than the natural hormone. The most important pharmacological effects include:
- increasing insulin secretion in a glucose-dependent manner;
- reducing inappropriate glucagon secretion;
- slowing gastric emptying, especially at the beginning of therapy;
- increasing satiety and reducing energy intake;
- improving glycemic control and body weight reduction;
- for selected drugs, reducing the risk of specific cardiovascular and renal events.
The indication depends on the specific preparation, dose, and registration. Not every drug used in diabetes is registered for the treatment of obesity. The most common adverse effects are nausea, vomiting, diarrhea, constipation, and abdominal pain. Complications requiring urgent diagnosis are also possible; therefore, treatment should remain under medical supervision.
GLP-1 analogs - how they affect appetite
The effect of GLP-1 receptor agonists on appetite is the result of the interaction between the gastrointestinal tract and the brain. Signals generated after GLP-1R activation reach, among others, the hypothalamus, the brainstem, and reward system structures. They reduce the motivation to seek food, weaken the response to food cues, and accelerate the onset of satiety during a meal. In some patients, they also reduce the intensity of cravings and interest in high-energy foods.
Key mechanisms include:
- greater postprandial satiety, allowing a meal to end earlier;
- reduced perception of hunger between meals;
- delayed gastric emptying, the significance of which may diminish during long-term treatment;
- altered neural valuation of reward, making certain foods less appealing;
- reduced daily energy intake, leading to a negative energy balance.
However, the medications do not selectively "burn" fat tissue. Weight reduction may involve both fat and a portion of lean body mass. For this reason, adequate protein intake, resistance training, hydration, and the assessment of nutritional deficiencies are important. Losing weight too rapidly may contribute to muscle loss, decreased exercise tolerance, gallstones, and greater skin laxity.
GLP-1 analogs - how they differ from the natural GLP-1 hormone
Natural GLP-1 is secreted after a meal in a pulsatile and local manner. Its half-life is approximately 1–2 minutes because it is rapidly broken down by the enzyme dipeptidyl peptidase 4, or DPP-4, and cleared from circulation. Only a small fraction of the secreted hormone reaches the systemic circulation in an active form.
Drugs acting on the GLP-1 receptor have been designed to resist enzymatic degradation and remain in the body from many hours to about a week, depending on the molecule. Therefore, they achieve more sustained receptor activation than physiological, short-term bursts of the hormone.
Feature | Natural GLP-1 | GLP-1 receptor agonists |
Source | intestinal cells | pharmaceutical preparation |
Secretion or administration | after food intake | regular subcutaneous administration or, in the case of a specific formulation, oral |
Duration of action | a few minutes | from hours to about a week |
Degradation by DPP-4 | very rapid | limited due to molecular modification |
Signal strength and continuity | physiological, meal-dependent | pharmacological, long-lasting |
Use | natural metabolic homeostasis | treatment of specific diseases |
Tirzepatide is not a simple GLP-1 analogue. It is a dual GIP and GLP-1 receptor agonist; therefore, its mechanism should not be equated with the action of a single natural hormone.
GLP-1 analogs - how they affect the skin and face
The terms „Ozempic face” or „post-Ozempic face” are not medical diagnoses. They describe the loss of volume in the cheeks and temples, deepening of the tear troughs, prominence of folds, skin laxity, and changes in the facial contour following significant body weight reduction. This phenomenon can occur after any rapid weight loss and does not indicate a toxic effect of a specific drug on the skin.
The primary mechanism is the reduction of superficial and deep facial fat compartments, which provide structural support for the skin. Age, photoaging, menopause, tobacco smoking, the extent and rate of weight reduction, baseline facial anatomy, as well as insufficient intake of protein and micronutrients also play a significant role. It has not been determined whether GLP-1 agonists directly accelerate skin aging. Experimental data also indicate potential anti-inflammatory and glycation-limiting effects, but their clinical significance remains uncertain.
Once body weight has stabilized, procedures available at Ambasada Urody tailored to the primary concern may be considered:
- volume restoration: volumetric lifting, contouring of the cheeks, temples, chin, and jawline with cross-linked hyaluronic acid, and autologous fat grafting;
- biostimulation and structural support improvement: Sculptra, Radiesse, Lenisna, and Juvelook;
- regeneration of thin or dehydrated skin: Profhilo, Sunekos, Karisma, polynucleotides, Xela Rederm, and mesotherapy with non-cross-linked hyaluronic acid;
- reduction of laxity: microneedle radiofrequency, HIFU, and laser treatments;
- complementary therapies: manual facial therapies, lymphatic drainage, and procedures supporting microcirculation.
These are not methods for treating the metabolic effects of the drug. Fillers restore volume, biostimulators and energy-based technologies support tissue remodeling, while mesotherapy primarily improves skin hydration and quality. The plan should take into account anatomy, weight stability, nutritional status, and the risks inherent to each procedure.
GLP-1 analogs - why GLP-1 supplements from the internet are not the same
Products advertised as „natural GLP-1”, „GLP-1 booster”, or „semaglutide substitute” usually do not contain the active hormone or an approved receptor agonist. They are typically mixtures of fiber, plant extracts, polyphenols, chromium, berberine, or other ingredients potentially intended to influence satiety, glycemia, or physiological incretin secretion.
Food, fermentable fiber, and certain gut metabolites can transiently increase endogenous GLP-1 secretion. However, this does not mean achieving pharmacological exposure comparable to the effects of semaglutide, liraglutide, or tirzepatide. The natural hormone is degraded within a few minutes, whereas the medications are resistant to degradation and have been evaluated in controlled clinical trials.
The key differences are:
- lack of evidence of equivalent efficacy in the treatment of obesity or diabetes;
- variability in the dosage, composition, bioavailability, and purity of supplements;
- the potential for interactions with antidiabetic drugs, anticoagulants, and other medications;
- the risk of delaying diagnosis or effective treatment;
- no grounds for independently substituting prescribed pharmacotherapy with them.
Particular caution should be exercised regarding injectable peptides sold on the internet and products claiming to contain semaglutide outside of legal pharmacy distribution. A dietary supplement, a compounded medication, and an approved medicinal product are distinct categories. They should not be treated as interchangeable.
