[Health Byte] Your AirPods Aren't the Problem. You Are.

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Here's something that's been circulating on Chinese social media lately: active noise-cancelling headphones are destroying people's hearing. Young users on Xiaohongshu and Douyin have been posting about tinnitus, gradual hearing loss, and pointing the finger squarely at their ANC gear. It's a relatable panic. Most of us living in Shanghai are wearing some form of noise-cancelling headphones every day, just to survive the Metro.

Turns out, the panic is misplaced. And the actual culprit is a lot less dramatic.

Dr Han Zhao, director of the ENT department at Huadong Hospital, is pretty direct about it: hearing damage comes from volume and duration, not from the technology inside your headphones. ANC, bone conduction, regular buds, it doesn't matter. The thing that's quietly wrecking your hearing is cranking it past a comfortable level for three hours straight while playing Black Myth: Wukong.

The part that is genuinely interesting

Here's the biology, and it's actually worth knowing. Your ear canal runs about 2.5 centimeters from the outer ear to the eardrum. Behind the eardrum, tiny muscles exist specifically to dampen loud sounds before they do damage. The catch: those muscles take a beat to respond. They need a neural signal from the brain first.

In-ear buds, the kind most of us default to, place sound right up against the eardrum. There's almost no reaction window. The protective muscles essentially never get the chance to kick in. That's why Dr Han ranks in-ear buds as the highest-risk option across all headphone types, and over-ear headsets as the safest. The cushioned ear cups isolate ambient noise without pressing sound directly against the eardrum. Ear-hook styles land somewhere in the middle.

So if you've been wearing in-ears daily for years, that's the thing worth thinking about.
The ANC issue is real, just not in the way people think

ANC headphones do carry a specific risk, but it has nothing to do with the technology damaging your ears directly. The issue is silence. ANC creates a near-quiet environment by generating reverse sound waves to cancel out ambient noise, and clinical data suggests that roughly 90 percent of people develop noticeable tinnitus after extended time in very quiet spaces. Human hearing has evolved to expect a constant low level of ambient sound. Remove it completely, and the brain starts generating its own noise to compensate.

Dr Han notes this is mostly a concern for middle-aged and older users with pre-existing mild hearing loss, who can develop persistent tinnitus from wearing ANC headphones in full-noise-cancelling mode without actually playing audio. For the rest of us, using ANC with moderate-volume music at reasonable durations carries minimal risk. That's not a dismissal, just context.

The rule nobody follows

The WHO's 60/60 guideline has been around for years: cap playback volume at 60 percent of your device's maximum output, and take a break after 60 continuous minutes of listening. It applies to every headphone type, full stop.

The problem, as Dr Han frames it, is that high-frequency hearing damage is invisible until it isn't. It starts at frequencies beyond the range of normal conversation (250-500Hz), so you won't notice anything wrong during your daily interactions. The first sign is usually recurring tinnitus. By the time speech comprehension starts to deteriorate, the damage is permanent.

That's not meant to be alarming. It's meant to be the reason to actually use the volume limiter on your phone.

The short version

Over-ear headphones for long daily use. Go easy on full ANC-only mode if you're on the older side or already have some hearing sensitivity. Keep volume under 60 percent. Pause after an hour. The technology in your headphones isn't what's going to get you. Your habits are.

If you want a proper hearing check or have ENT concerns, Huadong Hospital's international medical center is worth checking out:

You can visit Huadong Hospital's international medical center.

Tel: 6248-2423 (8am-4:30pm on workdays)

E-mail: huadongimc@163.com

Address: Bldg 1, 221 Yan'an Rd W., Jing'an District (延安西路221号1号楼)

Health Byte Tips

Lychees are everywhere right now, piled high at every wet market and fruit stand, and they smell incredible. Eat some. Just go in informed.

The sugar content is higher than most people expect: 15.2 grams per 100 grams, nearly three times that of watermelon. A medium lychee has about 18 grams of edible flesh, and that flesh is loaded with fructose specifically, which is harder on the liver than regular sugar and a problem for anyone managing gout. The dry mouth, sore throat, and gum irritation that hit after a lychee binge aren't just thirst. Residual sugar dehydrates oral tissue and feeds the bacteria that inflame your gums.

A few ground rules: 5 to 6 pieces at a sitting, no more than 10 to 15 a day for healthy adults. Elderly people, kids, and anyone with elevated blood sugar should keep it to 3 to 5. Rinse your mouth after, or brush later. And don't eat unripe lychees. Acute hypoglycemia from unripe fruit is a real clinical phenomenon with a name (lychee sickness) and it is not a fun afternoon. Diabetics, anyone with oral health issues, or anyone with digestive sensitivity should treat lychees as an occasional thing rather than a daily habit.

That's it. Go enjoy summer.

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About the Author

Cai Wenjun is a seasoned health reporter with Shanghai Daily. With extensive experience covering the local medical system, hospitals, health officials and leading medical experts, Cai has reported on major pandemics including SARS, swine flu and COVID-19, as well as developments in the local health industry.