Source: The Conversation – UK
Imagine scrolling through social media and seeing dramatic weight-loss results from people taking Mounjaro, Wegovy or Ozempic. They share photographs, discuss side effects and recommend ways to get the best results.
These personal stories can feel convincing, especially when they come from people with similar experiences. For someone struggling with their weight, advice from a supportive online community may seem more relatable than information from a medical professional.
A 2026 UK study involving 684 adults, including 544 current or former users of weight-loss medications, found that 48% of participants used social media as a source of information about the drugs. Healthcare professionals were consulted less frequently.
Although the survey cannot tell us how widespread this behaviour is across the UK, it raises an interesting question: why might people trust advice from strangers online, even when medical professionals can offer more reliable information?
Psychology offers some clues.
Why personal stories carry so much weight
People are often more receptive to advice from those they see as members of their own group. Psychologists call this social identity: the sense of identity we gain from belonging to groups with shared experiences, interests or goals.
When someone identifies strongly with a group, they may pay particular attention to what other members say and do. Advice from people who share their experiences can feel more relevant and trustworthy, even when those people have no medical expertise.
For someone who has experienced judgement about their weight, finding people who understand their difficulties can be especially valuable.
In research I co-authored, we explored how a shared sense of identity could be encouraged in a group-based exercise rehabilitation programme for people with chronic lung disease. Although we did not test whether this improved outcomes, the work illustrated how a sense of belonging might encourage mutual support.
Similar psychological processes may help explain the appeal of online weight-loss communities.
The difficulty arises when trust in someone with shared experiences extends to their medical advice. A person may genuinely have benefited from a medication without understanding its risks or whether their experience is typical.
How online groups shape what people believe
Online communities can provide encouragement and practical support, but they can also influence which experiences receive attention and which opinions become widely accepted.
A 2021 study involving interviews with 32 people in a professionally supervised online weight-management programme in China found that peer support encouraged motivation and a sense of belonging. However, comparisons with other members could also reinforce unhelpful group expectations.
Similar pressures may arise in online communities discussing weight-loss medication.
For example, someone who repeatedly sees dramatic success stories may begin to expect the same results from their own treatment. If a particular medication is widely praised, questioning its effectiveness or discussing negative experiences might feel uncomfortable.
These influences do not affect everyone in the same way, but they help explain how advice can become accepted within a group, even when there is limited medical evidence to support it.
And the information circulating online is not always reliable.
An October 2026 study examined 194 popular TikTok and YouTube Shorts videos about weight-loss medications, including semaglutide and tirzepatide, the active ingredients in Wegovy and Mounjaro.
Only 24% of all views of the assessed videos were for content researchers judged to be medically accurate. Some videos contained incorrect medical information, while others provided too little clinical information to assess their accuracy.
The researchers examined a selected group of popular videos, so their findings cannot be generalised to everything shared about weight-loss drugs online.
Nevertheless, the findings illustrate how a video can attract considerable attention without providing the information someone needs to make a safe medical decision.
The risks of unregulated weight-loss drugs
The consequences can become more serious when online recommendations move beyond sharing experiences of prescribed medicines to encouraging people to obtain drugs that have not been approved for medical use.
One example is “Reta”, the nickname for retatrutide, an experimental weight-loss medication being developed by pharmaceutical company Eli Lilly.
Retatrutide has produced substantial weight loss in clinical trials, but it has not been authorised for medical use in the UK. Its benefits and risks are still being assessed.
Despite this, products marketed as “Reta” have been supplied through unregulated channels.
In October 2026, the UK medicines regulator seized more than 12,000 counterfeit weight-loss injection pens labelled as retatrutide or tirzepatide from a Birmingham industrial unit.
Products supplied through these channels may contain incorrect ingredients, unreliable doses or harmful contaminants.
There is an important distinction between these products and regulated prescription medicines. Mounjaro and Wegovy are authorised for weight management in the UK when prescribed appropriately. Ozempic contains semaglutide, the same active ingredient as Wegovy, but is licensed for treating type 2 diabetes.
Even approved medicines can cause side effects and require appropriate medical assessment.
A personal recommendation, however convincing, cannot establish whether an unregulated product is genuine or safe.
Making better-informed decisions
Online weight-loss communities can provide valuable emotional support, particularly for people who feel isolated or judged. The challenge is recognising when shared experiences begin to influence decisions that require medical expertise.
Before following advice about weight-loss medication, consider whether the person recommending it is promoting a product or receiving payment. Be particularly wary of dramatic promises, suggestions to change prescribed doses without medical advice or offers to supply medication outside regulated pharmacies.
It is also worth considering whether an online community welcomes discussion of side effects and disappointing experiences, or predominantly celebrates positive results. Groups that allow people to question claims may provide a more balanced picture.
Anyone considering weight-loss medication should seek advice from a qualified healthcare professional. The UK medicines regulator advises obtaining these medicines only with a valid prescription from a registered pharmacy.
Understanding how group identity influences trust can help people recognise the value of online support while being more critical of the medical advice they encounter.
Shared experiences can offer reassurance and encouragement, but decisions about medication should be informed by reliable evidence and individual medical advice.
Andy Levy does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
Original source: https://analysis1.mil-osi.com/2026/11/03/why-people-trust-weight-loss-drug-advice-on-social-media-even-when-it-may-be-misleading/