Here’s what’s on the healthspan menu today:
- Prevent nearsightedness in children with this 1 thing
- Sleep trackers might be less beneficial than you think
- Inspiration for the Week: Xinmin Yang, the 72-year old bodybuilder
Prevent nearsightedness in children with this 1 thing
Peter Attia recently had Dr. Steven Dell an ophthalmologist to discuss everything eye health related. If you are curious about nearsightedness, cataracts, lens implants, sunglasses, laser surgery, etc… it’s well worth a listen.
The part I found most interesting was the discussion around nearsightedness (a subject near and dear to my heart as I’ve worn glasses since I was 12 years old).
Q: Why do humans develop nearsightedness?
There are 2 main drivers for developing nearsightedness:
- Deprivation from outdoor light
- Working and focusing on close objects (like looking at screens, reading, etc…)
The eye is extremely adaptable. When we are children and young adults, the shape of the eyeball can change based on the stimulus it receives.
If we spend all day inside watching TV, looking at screens, or reading, then our eyes will physically grow longer to better focus on closer objects. The consequence is our far vision gets worse.
There’s also little genetic influence in passing on nearsightedness. Most cases come from environmental factors.
Unsurprisingly, in educated-focused Asia they have upwards of 90% of the population being nearsighted. While in non-literate societies they had better vision as they did less near work.
Q: How can we prevent nearsightedness or improve our vision?
If you’re an adult and nearsighted then there’s nothing you can do aside from corrective laser surgery.
However, if you have children or plan to have kids there’s one way you can reduce their chances of developing nearsightedness. Simply have them spend 80 minutes a day outside in the sunlight.
In a research study of children 7-11 years old they found when they sent half of them outside for recess and the other half stay inside the group that went outside had 50% less incidences of nearsightedness.
The theory why this is effective is that when children’s eyes are exposed to bright sunlight their retina’s release dopamine. The dopamine release inhibits the growth of the eye, preventing the elongation of the eyeball which causes the nearsightedness.
Q: Are there any negative consequences to being nearsighted?
Any type of exercise where you can ideally go for up to 60 – 90 minutes continuously for. Running on a treadmill (or outside), cycling / biking, rowing, etc…
Q: What’s the Zone 2 prescription? How many times a week for how long?
Initially, I didn’t think being nearsighted had any negative side effects aside from having to wear corrective glasses or contact lenses. However, I was wrong.
If you’re nearsighted, you have a higher chance of developing eye issues like cataracts, myopic macular degeneration, glaucoma, tears and detachments of the retina.
Sleep trackers might be less beneficial than you think
On the Lex Fridman podcast, he interviewed Andrew Huberman. Huberman shared why he doesn’t like sleep trackers. We did a video on this clip.
Why he doesn’t think sleep trackers are beneficial is due to the influence of mindset.
Studies have been done where if they tell people that stress is performance enhancing, they perform better. On the flipside, if they tell people stress will make them perform worse, they perform worse.
To him a sleep tracker is no different. If you see your sleep score is bad you’ll go throughout the day with a negative bias. There’s no tangible benefit.
Just something to consider for all you sleep trackers out there.
Inspiration of the Week: Xinmin Yang, the 72-year old bodybuilder
When looking for impressive older people, I came across the story of Xinming Yang, a 72 year old active bodybuilder.
He’s been lifting weights since 1984, 1 year after China hosted its first-ever national bodybuilding championship. Apparently, China had banned bodybuilding in 1953 (thanks Mao!) which wasn’t lifted until 1983.
If you’re curious to know what he eats. He describes his diet as: “For breakfast, I usually have tomatoes, cucumber, oatmeal, eggs and some chicken breast. I’ve been eating like this for almost 10 years.”