Opinion: When it comes to health and social media, just because someone looks fit doesn't mean they're fit to give advice

In recent years, social media has become a powerful platform for influencers, who share everything from fitness tips to life hacks. Some influencers are fitness coaches, some are nutrition enthusiasts, and some... well, some are just fond of showing off their abs. While it's tempting to take advice from someone who looks fit and healthy, taking their word as gospel can have potential dangers for your health.

As comedian Dara Ó Briain once so eloquently pointed out, just as everyone who has teeth isn’t a dentist, everyone who eats food isn’t a nutrition expert. With this in mind, it’s wise to look carefully at the advice of self-proclaimed fitness gurus who often place appearance above science.

The rise of the "toothiologists"

Ó Briain famously coined the term "toothiologist" to describe people who present themselves as experts without any real qualifications. While it was originally meant as a joke about dietitians and dentists, it perfectly applies to today’s social media influencers who have adopted the title of "wellness expert" without actually having any formal education in nutrition or exercise science.

From BBC Global, The dangerous downsides of a fitness obsession

These "toothiologists" often look the part, showcasing toned bodies and aesthetic poses in carefully curated photos. Appearance can be persuasive; it's no surprise they have a big following. After all, in a world where visuals dominate, a six-pack can sometimes seem more convincing than a dietitian’s degree hanging on a wall.

When aesthetics overpower health

Social media has resulted in a shift in focus from health to aesthetics. Many influencers emphasise looking good rather than feeling good, sometimes promoting extreme diets, restrictive eating, or endless exercise as the path to a "perfect" body. However, the body you see on Instagram isn’t necessarily a healthy one. In fact, influencers often rely on unrealistic standards, and sometimes even unhealthy practices, to achieve those picture-perfect results.

Take, for example, the "detox tea" and "fat-burning" supplements so often seen on influencer profiles. These products promise quick weight loss, but they rarely deliver long-term results and may come with unpleasant side effects. Worse still, some of these products are not regulated, meaning you have no way of knowing what ingredients they really contain.

It’s easy to see how these trends are driven more by aesthetics than by a genuine interest in health. While influencers may look great in photos, they often sacrifice sustainable, long-term health for short-lived aesthetics. By focusing on appearance alone, they can lead followers to take up habits that do more harm than good, all in the name of looking Insta-worthy.

The risks of unqualified advice

But, what’s the harm in following a little friendly advice from your favourite influencer? Judging by the images, they must know what they are talking about. Here’s the problem: fitness and nutrition are fields of science, not just personal preference. Professionals who give nutritional advice have often spent years studying the intricacies of metabolism, the effects of various nutrients on the body, and how different exercise regimens affect muscle growth and overall health. Nutrition has advanced from general population-based guidance to personalised, prescriptive, periodised approaches, especially among elite performers.

Professor Louise Burke is the preeminent voice of performance nutrition globally and she has a great saying that the plural of anecdote is not evidence. I think this fits well in this discussion where influencers with their fit physiques espouse the virtues of practices that worked for them. Evidenced-based practice is the gold standard for good reason – there is science behind the approach. In contrast, influencers without these qualifications often base their advice solely on their personal experiences or current trends. They may not fully understand—or even care—about the scientific backing of the information they’re sharing. In some cases, they might genuinely believe in the advice they give, but a lack of knowledge can lead to recommendations that are outright dangerous.

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Professor Ron Maughan is another performance nutrition stalworth and his mantra is that if supplements sound too good to be true, then they probably are. For example, influencers might promote high-protein diets, low-carb regimens, or fasting routines that can be risky for individuals with certain medical conditions. And while it’s easy to assume these influencers are doing their research, it’s also easy for them to overlook the possible downsides of extreme diets, experimental supplement protocols or excessive workouts.

Why you should look for credentials

It’s understandable to feel inspired by an influencer who appears to be in great shape. But if you’re serious about improving your health, it’s essential to look for experts who know what they’re talking about. Registered dietitians, nutritionists with recognised certifications, and sport and exercise professionals with accredited qualifications are trained to give personalised, evidence-based advice.

These experts know that there’s no one-size-fits-all approach to fitness or nutrition. They understand that each body is unique and that there are no magic tricks or shortcuts for reaching your health goals. Instead of offering quick fixes, they’re more likely to guide you through sustainable, scientifically sound strategies tailored to your specific needs.

Read more: Should you trust health advice you receive on social media?

And when you consider the influence that social media has, the difference between real expertise and trendy advice becomes even more important. When an influencer gives advice, they’re often telling it to thousands—even millions—of followers. Misinformation can spread fast, and when it comes to something as important as your health, taking shortcuts can be dangerous.

How to spot reliable advice

Check their credentials: Look for registered dietitians, certifications like a degree in dietetics, a personal trainer certification from a reputable organisation, or similar qualifications in their field.

Watch for buzzwords: If you see phrases like "quick fix," "miracle cure," or "detox," it’s a red flag. Qualified professionals know there are no instant solutions.

Look at their content focus: Are they more interested in helping you feel better, or in helping you look better? While there’s nothing wrong with wanting to look good, focusing solely on appearance without considering the science behind it can be risky.

Research their recommendations: If they’re promoting a diet, exercise, or supplement, try to find out if there’s scientific evidence to back it up. Reputable professionals will usually share links to studies or explain the science behind their advice.

Consider your own needs: Health is personal. Just because something worked for one influencer doesn’t mean it will work for you. If you have specific health conditions, dietary needs, or fitness goals, seek advice from a qualified professional.

Trusting the experts — not just the influencers

Social media can be an amazing source of inspiration, but when it comes to your health, it’s important to get your facts from trained professionals. Following the advice of unqualified influencers could have real consequences, from nutrient deficiencies to injury, or even long-term harm. Next time you’re tempted to try the latest fad from a topless influencer, remember that just because someone looks fit doesn’t mean they’re fit to give advice.

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