Debunking Four Summer Health and Nutrition Myths

Summer is a season full of sunshine, barbecues, and well-intended health tips. Unfortunately, some popular beliefs about summer health and nutrition don’t hold up under scientific scrutiny. These myths often spread through anecdotes or fear-based messaging, leading people to worry or make misguided choices. Let’s shine a light on four common summer health myths – and see what the science actually says about each.

Myth 1: Sugar Makes Kids Hyperactive

Many parents swear that sugary treats send their kids bouncing off the walls. In reality, no solid scientific evidence links sugar intake to hyperactive behavior in most children. A comprehensive meta-analysis of 16 studies concluded that sugar “does not affect the behavior or cognitive performance of children” (Wolraich et al., 1995). In other words, normal doses of sugar don’t make kids act wild – the expectation of a “sugar rush” might be the real culprit. In one clever study, mothers who believed their sons had consumed sugar (when in fact the kids hadn’t) rated them as more hyperactive and even subtly changed their own behavior toward the children (Hoover & Milich, 1994). This placebo effect helps explain why the sugar-hyperactivity myth persists.

Of course, excessive sugary food is still unhealthy for other reasons (like promoting weight gain or displacing nutritious foods), but it isn’t to blame for ADHD or rambunctious behavior in everyday settings (Ansel & Ellis, 2022). The excitement of parties or the context in which sweets are consumed (birthday games, outdoor play) is more likely to trigger energetic behavior than the sugar itself.

Does the grill cause cancer?

Myth 2: Grilling Causes Cancer

Grilling and barbecuing are beloved summer pastimes – but some people worry that charred, smoky meats will automatically give them cancer. The truth is more nuanced.

Cooking meat at very high temperatures (like on a grill) can create some carcinogenic compounds, but moderate barbecuing is not inherently a cancer sentence. Research does show that cooking methods like frying or grilling can form heterocyclic amines (HCAs) in the charred crust of meat and polycyclic aromatic hydrocarbons (PAHs) in smoke, both of which can damage DNA in large enough amounts (National Cancer Institute, 2020). However, the actual cancer risk from occasional grilling is unclear and likely quite low.

According to experts, while heavy consumption of well-done or burnt red meat has been associated with certain cancers, “a definite conclusion on this is still up for debate” regarding typical grilling (Egan, 2025). In other words, barbecue is not automatically toxic – it’s all about how you grill and how much charred meat you eat. You can enjoy summer cookouts more safely by taking a few simple precautions. For safer grilling, experts recommend several steps:

• Keep the grill clean and avoid heavy smoke: Remove old drippings that can cause flare-ups, and consider using foil or an indirect grilling method to reduce smoke contact with food.

• Trim fat and avoid charring: Excess fat dripping on coals creates more smoke and PAHs, so choose leaner cuts and trim visible fat (Moffitt Cancer Center, 2025). Cook meat just until done – not to the point of charred “blackened” ends – and discard any heavily blackened pieces.

• Use marinades and mind the heat: Marinating meat (especially with acidic ingredients like vinegar or lemon) can reduce HCA formation. Cook at a moderate temperature or raise the grill rack to prevent extreme charring. Flip meat frequently to prevent any one side from burning (Dana-Farber Cancer Institute, 2019).

• Grill fruits, veggies, and lean proteins: Remember that cancer concerns largely apply to red and processed meats. Grilling vegetables, fruits, or alternatives like tofu entails no HCA/PAH issue – so mix up your barbecue menu with plant-based foods (Dana-Farber Cancer Institute, 2019).

Bottom line: enjoy your summer barbecues in moderation. There’s no evidence that a few weekend cookouts will cause cancer. Using the tips above will further minimize any potential risks, so you can savour that smoky flavour with peace of mind.

Sunscreen: What does the science say?

Myth 3: Sunscreen Is Toxic

On social media and in the rumor mill, you might hear that sunscreen ingredients are “poisonous,” or even that wearing sunscreen causes cancer. Such claims are not supported by scientific evidence – in fact, they are dangerous myths.

Dermatologists emphasize that modern sunscreens (whether “chemical” formulas with organic filters or “mineral” formulas with zinc oxide) are rigorously tested and not harmful to human health (Zeichner, 2019). A thorough review of studies in 2011, for example, found no evidence of toxicity in humans from any common sunscreen ingredient, including oxybenzone – an ingredient often maligned by rumours (Burnett & Wang, 2011). Meanwhile, we do have abundant evidence that UV radiation from the sun causes skin cancer and premature aging. “There is no evidence that wearing sunscreen causes skin cancer. What we do know is that the sun causes most skin cancers,” stresses Dr. Elizabeth Buzney of Harvard Medical School (Buzney, 2024). In fact, regular sunscreen use has been shown to dramatically cut skin cancer risk – one long-term study in Australia found that daily sunscreen users had 50% fewer melanomas compared to those who did not use sunscreen regularly (Green et al., 2011). Health authorities worldwide, including the American Academy of Pediatrics and the CDC, recommend everyone over 6 months old use sunscreen on exposed skin whenever UV exposure is expected (AAD, 2018).

It’s true that a few sunscreen products were recalled in recent years due to contamination with benzene (a solvent not intended to be in sunscreens), but those recalls were out of an abundance of caution and do not mean sunscreen itself is unsafe (MD Anderson Cancer Center, 2024). If you remain concerned, you can choose mineral-based sunscreens, which sit on the skin’s surface and are not absorbed – but note that even chemical sunscreens, which do get absorbed, have not been shown to cause harm (Gold, 2019). The benefits of sun protection far outweigh any unproven risks from trace ingredient absorption. Wearing sunscreen is a key part of a smart sun-safety routine (along with seeking shade and wearing hats and sunglasses), and it significantly reduces your risk of skin cancer and skin damage(Skin Cancer Foundation, 2022). In short, sunscreen is a life-saver, not a toxin.

Breaking a sweat burns more calories, right? Wrong.

Myth 4: Sweating Means More Fat Loss

“Work up a sweat to burn more fat!” – You’ve probably heard this fitness folklore. It’s commonly believed that if you’re drenched in sweat after exercise, you must have burned a ton of calories, and if you barely sweat, you didn’t work hard enough. In reality, sweating is not a reliable indicator of fat loss or calorie burn. Sweat is mostly just water – about 99% water, with some salts – and its main function is to cool you down, not to expel fat from your body (Eagle, 2024). You might notice a lower number on the scale after heavy sweating, but that’s only temporary water weight loss. As soon as you rehydrate, the weight returns, because you haven’t lost a significant amount of fat (Eagle, 2024). In fact, it’s not necessary to sweat at all to burn calories. Your body can burn plenty of calories during activities like swimming or winter jogging where you might not sweat much, and you’ll still be using energy and reducing fat stores. The amount you sweat is influenced by factors like temperature, humidity, genetics, and fitness level – not just exercise intensity. For example, if you exercise on a hot, humid day, you’ll likely sweat much more than if you did the exact same workout in a cool gym, but your calorie expenditure and fat burn could be identical in both cases (Romaine et al., 2020). A study on yoga found that people burned the same number of calories in a session, whether it was performed in a super-heated “hot yoga” studio or at normal room temperature – the hot class made them sweat buckets, but it didn’t translate into extra fat burned (Sanchez et al., 2020).

What actually happens when you “burn” fat? Your body breaks down fat molecules for energy, and the fat’s components are mostly exhaled as carbon dioxide with the remainder excreted as water (through urine, sweat, etc.). Remarkably, over 80% of the fat we lose leaves our body via the lungs when we breathe out – not through perspiration (Meerman & Brown, 2014). Sweat might contain trace amounts of fat, but it’s negligible; sweat is not the mechanism of fat loss, only a side effect of temperature regulation. Thus, wearing sauna suits or sweatring through intense summer heat may make you feel like you’re “burning more fat,” but all you’re losing is water (and electrolytes), not body fat. To effectively lose fat, focus on sustainable exercise and diet (creating a calorie deficit), not on how soaked your shirt gets. And remember to rehydrate after sweating to maintain healthy fluid balance – your body needs that water, even if the scale momentarily tricks you into celebrating a “loss.” In summary, sweat itself is not your fat crying – it’s just your body keeping cool. Fat loss happens from within, regardless of how sweaty you get on the outside.

Conclusion

Misinformation never takes a vacation, even in summertime. Myths about sugar highs, “toxic” sunscreen, killer cookouts, or magic sweat can spread easily because they often tap into our intuitions or fears. But as we’ve seen, the scientific evidence tells a different story. Children don’t turn hyperactive from birthday cake alone. Your Fourth of July burger isn’t basically a cancer pill – moderate grilling is fine with simple precautions. Sunscreen isn’t a poison; in fact, it’s a proven protector against cancer. And drenching sweat isn’t a sign of fat melting away – it’s just your body air-conditioning itself.

By understanding the facts behind these myths, you can make smarter health choices and enjoy your summer with a little less worry. In an age of viral pseudoscience and fear-based messaging, evidence is your best friend. Stay curious, stay critical, and have a happy, healthy summer!

#nutrition #nutritionalscience #factsnotfear #nutritionmythbusting #fitness

References

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2. Bain, J. (2024, July 1). Sunscreen safety – the facts. The Skin Cancer Foundation. Retrieved from https://www.skincancer.org/blog/sunscreen-safety/

3. Burnett, M. E., & Wang, S. Q. (2011). Current sunscreen controversies: a critical review. Photodermatology, Photoimmunology & Photomedicine, 27(2), 58–67. https://doi.org/10.1111/j.1600-0781.2011.00557.x

4. Buzney, E. (2024). Quoted in Bain, J. Sunscreen safety – the facts. The Skin Cancer Foundation.

5. Dana-Farber Cancer Institute. (2019, October 9). Burnt food and carcinogens: What you need to know. Insight Blog. Retrieved from https://blog.dana-farber.org/insight/2019/09/does-burnt-food-cause-cancer/

6. Eagle, R. (2024, October 30). Does sweating help burn calories? Medical News Today. Retrieved from https://www.medicalnewstoday.com/articles/does-sweating-burn-calories

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8. Gold, S. S. (2019, May 20). The science of sunscreen: 3 experts tackle common myths about its safety. Johnson & Johnson. Retrieved from https://www.jnj.com/health-and-wellness/sunscreen-safety-myths-experts-tackle-the-science-of-sun-protection

9. Green, A. C., Williams, G. M., Logan, V., & Strutton, G. M. (2011). Reduced melanoma after regular sunscreen use: Randomized trial follow-up. Journal of Clinical Oncology, 29(3), 257–263. https://doi.org/10.1200/JCO.2010.28.7078

10. Hoover, D. W., & Milich, R. (1994). Effects of sugar ingestion expectancies on mother–child interactions. Journal of Abnormal Child Psychology, 22(4), 501–515. https://doi.org/10.1007/BF02168088

11. Meerman, R., & Brown, A. J. (2014). When somebody loses weight, where does the fat go? BMJ, 349, g7257. https://doi.org/10.1136/bmj.g7257

12. MD Anderson Cancer Center. (2024, May 31). 9 sunscreen myths debunked. Retrieved from https://www.mdanderson.org/cancerwise/sunscreen-myths-debunked.h00-159697545.html

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14. Sanchez, J., et al. (2020). Quoted in Eagle, R. Does sweating help burn calories? Medical News Today.

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