The top 10 most-searched health myths in the UK, according to TikTok and Google

Reviewed by our clinical team

Turning to Google and social media platforms like TikTok for medical advice has become commonplace, and in extreme cases can even develop into Cyberchondria - a compulsive form of problematic use of the internet in relation to health queries.  

In 2023, #HealthTok and #HealthTips hashtags amassed over 2.6 billion and 11.2 billion views respectively on the app, but as many as 98% of videos contain misleading information or advice which can spread like wildfire with the click of a share button. 

To uncover how trusting Brits are when it comes to their face value belief in online health information, we surveyed 1,000 adults to get their views. While three quarters (77%) of Brits would still trust their GPs or pharmacists the most when it comes to accurate health information, more than a quarter (27%) would rely on Google, and nearly one in ten (8%) trust TikTok the most. 

Despite this, 53% would go to Google first when they have health-related questions, and 15% would go to social media platforms (TikTok, Instagram or YouTube) before speaking to their GP. Nearly two-fifths (39%) professed to changing their health behaviour based on something they saw on social media, but only 35% say they always fact-check health claims before believing or even sharing them. 

More than half of Brits (59%) admit to believing a health myth that they later found out was false, a number that rises to 67% amongst women (compared with 51% of men). 

In a bid to combat health misinformation online, we’ve combined Google search trends with TikTok video data to reveal the country’s most searched for health myths, and LloydsPharmacy Online Doctor’s experts break down which ones are true - and, more importantly, which ones are false and need to be ignored.

We used monthly search data for terms relating to each health myth across Google and TikTok, analysing average monthly search for related keywords, three month search volume change and year-on-year search volume change, as well as average monthly search data for related keywords on TikTok. These metrics were then used to create a weighted rank score, rating which health claims are the most widely searched for across the internet.

The top 10 health myths

1. Washing your hair daily causes baldness

Verdict: False

With 14,800 monthly searches on Google and 9,520 on TikTok, queries around washing your hair daily causing baldness are the most searched for false health claim in the UK - but it’s actually only believed by 6% of women and 13% of men. 

This claim is a myth. In fact, the opposite can often be true, as washing your hair helps prevent buildup that can interfere with growth. 

Dr Bhavini Shah, GP at LloydsPharmacy Online Doctor, says: “While frequent hair washing can temporarily make hair feel drier, it does not cause the type of follicle damage that leads to baldness, and there is no scientific evidence to support the claim that washing your hair every day can lead to hair loss. Male- and female-pattern hair loss are driven by genetic and hormonal factors. The NHS confirms that normal hair shedding is around 50–100 strands per day, and this hair was due to fall out naturally, whether in the shower or on your pillow.”

2. 'Starve a fever, feed a cold'

Verdict: False

A third of Brits (34%) believe the old wives’ tale that you should ‘starve a fever, feed a cold’, but a common theory is this is a mistranslation as the original was: ‘feed a cold, stave off a fever’. This would make sense, as Dr Shah explains: “illness increases your body’s metabolic demands, regardless of whether you have a fever or a cold, and so it’s important to prioritise rest, hydration, and maintaining a balanced diet during any infection. 

“The ‘starve a fever’ saying is a historical phrase, not a medical recommendation.”

Queries around the false adage ‘starve a fever, feed a cold’ amass 12,170 monthly searches on Google, and 6,370 searches on TikTok in the UK.

3. You should poo once a day or you're unhealthy

Verdict: False

This digestive myth is believed by 23% of women and 28% of men in the UK. While regular bowel movements are a sign of healthy digestion, ‘regular’ doesn’t mean the same for everyone.

The reality is, normal bowel frequency can range from three times a day to three times a week. What matters most is consistency for your body and the absence of pain or straining.

Dr Shah says: “Some people have a bowel movement every day, others every other day — and both can be perfectly healthy. A ‘normal’ bowel habit is defined by what’s right for the individual, as long as stools are soft and passed without discomfort. Constipation isn’t just about missing a day; it’s where you have changes to how you poo, which includes not pooing as often or finding it hard to poo.”

Queries around pooing once a day to stay healthy garner 6,760 monthly searches on Google and 5,340 searches on TikTok every month on average in the UK.

4. The flu shot gives you the flu

Verdict: False

Despite clear NHS guidance, a quarter of Brits (26%) believe the flu vaccine can give you the flu, which is incorrect. Searches around the flu vaccine causing flu are also up 215% YoY, demonstrating the current prevalence of the myth amongst the public. It’s important to know that the injected flu vaccine contains inactivated virus, and as such cannot cause flu. 

Dr Shah says: “You cannot catch the flu from the flu jab - the virus is inactivated, so it’s not possible. What you might get is a short-lived sore arm, a slight temperature, or achiness, which are signs the vaccine is teaching your body’s immune system how to protect itself from the disease.”

5. Eating at night makes you gain more weight

Verdict: Neither true nor false

Searches around eating at night causing weight gain were up 105% between April and July 2025, and it is a claim that’s been perpetuated by dieticians for decades, but in truth this isn’t a straightforward true or false answer as there are a few different factors influencing the outcome. 

Vinny Kodamala, Nutritionist at LloydsPharmacy Online Doctor, explains: “It’s true that Harvard researchers did a study in 2022 to determine if the time of day in which you ate was important, and they did find that eating later in the day increased participants’ hunger, decreased the number of calories they burned, and promoted fat storage - which, over time, could lead to weight gain. 

“However, this was a very small study of just 16 people, and it does not definitively show that eating late at night “causes” weight gain. Instead, it tells us that when we’re out of sync with our circadian rhythm, which prepares our body for periods of fasting, feeding and sleeping, it can affect our weight, but for the majority of people it’s more about what and why we’re eating at those times, rather than the time itself.

“Leaving long gaps between eating and finding yourself extremely hungry can lead to poor or less healthy food choices and overeating, which can increase your calorie intake for the day. So can habits such as snacking while watching TV in the evening, which has been proven to reduce lipid oxidation - meaning you burn less fat - compared with eating the same foods in the morning. 

“Again though, a lot of this is down to what you’re eating. Evening snacks tend to be high in sugar and fat, and late night eaters tend to have shorter overnight fasting periods which means there is less time for the body to reset its metabolism. As such, avoiding late-evening snacks may support weight loss, but the relationship is not necessarily definitive.”

Two fifths (40%) of Brits believe that eating at night makes you gain more weight, and women are more likely to believe this than men (42% vs 37%). If you’re concerned about how your meal timings might be impacting your nutrition or weight, your GP can offer personalised guidance and safe, effective weight loss and weight management advice.

6. Sweating more = burning more fat

Verdict: False

There are 570 searches on TikTok around the ‘sweating more = burning more fat’ claim each month, and 730 on Google - up 47% over the last three months. Over a quarter of Brits (27%) also admit to believing this claim, despite it being a myth. 

Vinny Kodamala says: “Sweating isn’t a sign that you’re burning more fat or calories - it’s simply your body’s cooling system, helping to regulate temperature rather than measure fat loss. Yes, you are likely to sweat more after an intense workout than a gentle one, but it’s the intensity of the exercise, not the amount of sweat, that matters.

“Sweat is mostly water and electrolytes, not melted fat. While you might lose water weight temporarily when sweating a lot, this comes back once you rehydrate. Fat loss comes from burning more calories than you consume over time, through a combination of diet and exercise - not from how much you sweat.”

7. You need to drink eight glasses of water every day

Verdict: Neither true nor false

Half of Brits (47%) admit to believing this claim, and it’s the fifth most searched for myth on TikTok in the UK, with 1,950 searches a month. However, the reality is not as clear cut as that, and the ‘eight glasses a day’ myth comes from a 1945 US Food and Nutrition Board which recommended 2.5 litres of water a day, but this was not based on any research and also stated that most of the water intake should come from food sources. 

Vinny Kodamala explains: “If your body is dehydrated, you’ll get thirsty, it’s that simple. If you’re not getting as thirsty as you believe you should be, because you don’t feel you need the 6-8 glasses of water, it’s likely you’re getting a lot of hydration from your diet. 

“We always recommend drinking two litres, or eight glasses, of water as this is a good gauge for staying hydrated that everyone understands, but we also understand that it can be hard to remember - especially if you have a busy schedule. 

“That’s why it’s important to remember that hydration isn’t just about water - a variety of everyday foods like cucumbers, tomatoes, and strawberries contain a high water content and essential nutrients that support hydration and overall health. 

Getting additional hydration this way can also be a great way of introducing important electrolytes into your diet, such as sodium and potassium. Electrolytes play an important role in helping generate electricity for nerve impulses, contract muscles, and move fluids through your body.  

“Keeping these fruits and vegetables as a consistent fixture in your everyday diet will contribute to better hydration, and one way to make this more enjoyable is to find those water-rich foods that you enjoy.”

8. You can't get pregnant on your period

Verdict: False

Interestingly a fifth (20%) of British men believe this myth, compared with 16% of women, which is risky to anyone using this method as a form of contraception. Searches for this claim on Google were also up 43% over the past three months.

The reality is that while the chance is lower, it is still possible to get pregnant during your period. 

Emma Ostridge, Sexual Health Nurse at LloydsPharmacy Online Doctor explains: “A person who ovulates is most fertile during the ovulation period (around the middle of your cycle), but sperm can survive for several days, and if ovulation occurs shortly after your period - which it might if you have a shorter cycle or ovulate early -  it’s possible to conceive. 

“The only way to prevent pregnancy is to practice safe sex every time you have sex, whether that is using a combined hormonal contraceptive method (which works to prevent ovulation) or a condom. Speak to a local pharmacist or GP if you are unsure, who can explain the different contraception methods such as the birth control pill or the contraceptive injection.”

9. Brown sugar or honey is healthier than white sugar

Verdict: Neither true nor false

This particular claim garners 1,740 searches on Google a month - up 21% YoY [July 2025] - and 1340 searches on TikTok every month in the UK, despite it being misleading. 

Brown sugar is simply made by mixing white sugar with molasses, giving it that slightly caramel flavour that distinguishes it from white sugar, but it is still a high-calorie and low-nutrient sweetener. 

Honey is often considered a “healthier” option because it’s a natural sweetener made by bees from flower nectar and contains antimicrobial, anti-inflammatory, and antioxidant properties. It has long been used as a home remedy for sore throats, coughs, and allergies, and its lower glycaemic index means it’s less likely to cause a rapid rise in blood sugar.

However, honey is still an added sugar, and should be consumed in moderation as part of a balanced diet.

Vinny Kodamala says: “We advise adults in the UK to consume no more than 90 grams of total sugars per day - which does include 30 grams of what we refer to as ‘free sugars’ such as those added to food and drinks, and sugars naturally present in things like honey. 

“While honey does have nutritional properties, it still contains 15g of sugar per 20g serving, meaning it provides mostly empty calories and just like other sugars, excessive consumption can lead to weight gain, high blood sugar, and other health problems. There is no significant health benefit to choosing one over the other.”

10. Muscle turns into fat if you stop working out

Verdict: False

A quarter of Brits (24%) believe that muscle turns into fat if you stop working out, which is false. It’s a common misconception, but muscle and fat are distinct types of tissue and one cannot ‘turn into’ another one. 

Vinny Kodamala explains: “When you stop exercising, your muscles will likely shrink or atrophy due to inactivity and your body fat percentage may increase, which gives the appearance of muscle turning into fat, but it’s actually just a change in your body’s composition. 

“When you lose muscle mass as well, your resting metabolic rate may decrease, which makes it easier to gain weight if you don’t adjust your calorie intake. Keeping active helps preserve muscle and maintain your weight.”

How to spot a health myth - tips from the experts

1. Check the source: if a claim comes from a social media influencer, an anonymous forum, or a brand selling a related product, treat it with caution.

2. Look for scientific evidence, not anecdotes: personal stories are compelling, but studies published in reputable medical journals, statements from the NHS, or guidelines from the World Health Organisation are more trustworthy. 

3. Watch out for ‘miracle’ or ‘quick-fix’ language: If something claims to cure, detox, or completely prevent a condition with minimal effort, it’s probably too good to be true.

4. Be wary of fear-based messaging: Headlines or videos that rely on shock value or scare tactics are often more about clicks than clinical truth.

5. Cross-check before you share: Even if something sounds plausible, search for the claim alongside trusted sources like the NHS. If you can’t find confirmation from multiple credible outlets, hold off on passing it along.

6. Ask a professional: When in doubt, speak to your GP or pharmacist. They can help you separate evidence-based advice from common misconceptions.

From daily hair washing to late-night snacking, our analysis shows that health myths - no matter how persistent - can easily mislead even the most well-intentioned among us. In a world where TikTok trends and Google searches can outpace verified medical guidance, misinformation spreads faster than the truth. 

While some myths are harmless, others can lead to risky health behaviours or prevent people from seeking the care they need. 

The key takeaway is clear: pause before you believe, verify before you share, and turn to trusted medical professionals and reputable sources for your health advice. In an age of viral content, critical thinking isn’t just smart - it’s essential for protecting your health and wellbeing.

Methodology

We compiled a list of keywords related to various health myths, ensuring a diverse representation across topics such as nutrition, pregnancy, fitness, and misinformation.

For each keyword, we gathered data from two primary sources: Google Keyword Planner for search metrics on Google, and KeywordTool.io for average search volume on TikTok [pulled July 2025, UK searches]. 

We then grouped the keywords by the underlying health myth they stem from, allowing us to analyze them in context. To prioritize and rank the myths, we created a weighted score using four key metrics - Google average monthly searches, three-month change, year-over-year change, and TikTok search volume - each weighted equally. 

These scores were normalised and scaled to a 1-100 score to generate a weighted rank range to provide a relative measure of visibility and interest across platforms. All missing data was filled with zeros to maintain consistency during analysis.

LloydsPharmacy Online Doctor surveyed 1,000 people 04/08/2025. 

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