As human beings, we often dwell on "what ifs" in life, like this one: “What if I had done things differently when I was younger?” 

While I don’t encourage this type of thinking — it can create unnecessary anxiety and stress over things we cannot change — it’s still valuable to reflect on past mistakes and lessons. Doing so can help us grow into improved versions of ourselves. But it’s even better if we can learn from others’ mistakes before we make them too.

As a neurologist, I look back on my younger years through the lens of neuroscience and brain health. It gives me a unique perspective on things I wish I had done differently.

Here are three that stand out that I regret doing — and that you might still be able to avoid:

1. Drinking soda daily

When I was a teenager, my parents and I didn’t fully understand the harm excessive sugar intake could have on my health. Every day after school, I drank one or two cans of soda and ate cookies along with it.

While my diet today is by no means perfect, I’ve made significant changes, and I rarely drink soda. Research is clear: Diets high in sugar contribute to insulin resistance, an increased risk of type 2 diabetes and cardiovascular disease, chronic inflammation, and even cognitive decline.

Long-term, excessive sugar intake may elevate the risk of dementia, including Alzheimer’s disease. 

Fortunately, reducing my soda consumption and overall sugar intake can help mitigate some of these harmful effects — though some long-term consequences may not be fully reversible.

2. Listening to really loud music

Like many people, I love music. When I was younger, I had the unhealthy habit of blasting it in my ears. 

Excessive noise exposure can lead to hearing loss, hearing sensitivity, and tinnitus. Damage to the cochlea’s hair cells is irreversible because these cells do not regenerate. Research has shown that hearing impairment is often associated with mood disorders such as depression and anxiety.

Additionally, multiple studies link hearing loss to an increased risk of cognitive decline and dementia. This is likely because when your brain struggles to process sounds due to hearing loss, it diverts cognitive resources away from memory and thinking. 

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As I age, my hearing will likely decline. Although I still use headphones and listen to music, especially when working out, I now limit the volume to 60% or lower and restrict listening time to no more than 60 minutes per day.

If you develop hearing impairment, addressing it as soon as possible can help reduce the cognitive burden. Hearing aids have been found to reduce the risk of dementia in individuals with hearing loss by not only delaying cognitive decline but also improving overall brain health.  

Interestingly, the increased risk of cognitive decline does not apply to people who were born deaf or experienced hearing loss at a very young age, as their brains develop cognitive adaptations to mitigate the negative impact. 

3. Not taking sleep seriously

Although I didn’t grow up with smartphones, I still spent countless nights staying up late watching TV or playing video games. At the time, I didn’t understand the importance of sleep. Sleep duration and quality are critical to brain health — not just for rest but also for brain development during adolescence, memory consolidation, emotional processing, and waste clearance.

Now that I have a better understanding of sleep’s role, I strive to get 7-to-9 hours of sleep per night. My job as a doctor doesn’t always allow that, especially when I’m on call. However, as a strong advocate for brain health, I push for change in our profession — particularly during medical training — to ensure that more doctors get the rest they need.

Long-term structural changes to the brain may have lasting consequences. But some cognitive and behavioral impacts associated with poor sleep can be reversed by improving sleep habits.

Baibing Chen is a double-boarded certified neurologist and epileptologist practicing at the University of Michigan. Find him on Instagram, TikTok, and YouTube.

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