Escaping the cult of sunscreen

Intelligent choices come from comparing the costs vs. benefits of all known alternatives, and choosing the one alternative with the best cost/benefit ratio.

Unfortunately, Americans often try instead to avoid any risk, no matter how small, at any cost, no matter how high.  This is why our healthcare is so expensive.  It’s also why we receive nutty proposals like the one I got today from the local high school.

Today, our child’s high school sent a bulletin recommending all parents force their children to wear sunscreen at all times during school hours, to prevent skin cancer.  Is that smart?  Let’s examine the costs and benefits, and compare them to alternatives.

  • For practical purposes, melanoma is the skin cancer that kills you, and hence the one worth focusing on.
  • Over 95% of melanomas occur in people with blue or green eyes.  Our high school is majority Asian;  less than 5% of students, or fewer than 175 people, have blue/green eyes.
  • Annual incidence of melanoma among non-Caucasians is less than 1 in 25,000.
  • Incidents usually occur after decades of exposure, but let’s say 10 years.
  • Skin cancer is proportional to sun exposure, occurring mostly in people who spend hours a day outdoors with no protection.
  • Our students spend between 0.5 and 1.5 school hours outdoors, depending on whether they have physical education class.  Students take an average of 2 years of PE, so over their four years, average daily exposure per student, per school day is about 1 hour.
  • Skin cancer is far more associated with episodes of sunburn than with long-term, low-level exposure.  Almost no one, other than blue-eyed people, can become sunburned by 1 hour of incidental sun exposure.
  • Sunscreen costs $15 a bottle.  Bottles last no more than two weeks if you use them every day, reapplying as directed.  Suppose all 3500 students followed the school’s advice.  They would use 91,000 bottles of sunscreen a year, costing almost $1.4 million.
  • Nearly all store-bought sunscreens rely on oxybenzone, homosalate, and similar chemicals, which are suspected hormone disruptors, and which have not been reviewed by FDA since the 1970s.
  • The developed world suffers from an epidemic of Vitamin D deficiency, primary caused by a lack of sun exposure.

Conclusion:  by following the school’s advice, at a cost of $1.4 million a year, we might save at most one hundredth (1/100) of a student life per year, and probably far less — while causing unknown harm due to vitamin deficiency and hormone disruption.  Minimum cost per life saved:  $140 million.

Those who don’t think rationally about cost/benefit will protest here.  Life is precious!  If we could save just one life, maybe it’s worth $140 million.  Well, maybe.  But let’s first compare alternative ways of saving lives at the same venue, and choose the cheapest.

For example, for $50k a year, the school could hire a full-time suicide counselor.  The school has a suicide every few years.  If a counselor saved just one fourth of them, say one student every 10 years, the cost would be $500k per life saved — about 250 times more effective than ubiquitous sunscreen.

That’s cost benefit analysis.  It’s not an exact science.  It doesn’t need to be exact, when the difference in effectiveness is so stark.


The Web promotes pithiness

Ever noticed that Malcolm Gladwell books read like magazine articles stretched out to book length?  Gladwell is naturally pithy, spent a lot of time writing for periodicals, and so his natural rhythm seems to be 7,000 words — but he writes for an inflexible genre that requires 70,000.

Similarly, ever noticed that pop song lyrics often peter out?  The first verse is clever, the second trite, the third nonsensical.  This pattern has been true for decades, even in famous anthems like Strawberry Fields Forever.  (If you haven’t noticed this before, listen to a few songs, and be amazed.)  The problem is that the pop format is standardized, running about 2.5 minutes, structured something like verse 1, verse 2, chorus, verse 3, bridge, chorus.  If the songwriter’s idea doesn’t fit, then, for commercial reasons, he needs to add filler.

A great thing about the Web, still in flux even now, is to shake up these standard formats.  Things can run as short or long as needed.  Especially shorter.

This is counterintuitive.  The Web made it free to publish an infinite number of words, so one would think we’d get longer books, articles and other media.  Instead, the opposite happened.

There are three reasons it turned out this way.

  • Web search, e.g. Google, reduced the need for well-defined content categories.  This created an opening for new ways of communicating.  The question a book agent used to ask — “what shelf would this book idea go on?” — became less relevant.
  • In a world flooded with content, the value of pithiness went up.  You now have instant access to thousands of times more content than you can ever consume.  The scarce resource is not money or content, but time.
  • Fulfillment costs went to zero, so the barrier to pithiness went down.  When selling a traditional book, most of the cost went into printing, binding and shipping.  To have a meaningful amount left over for the author and publisher, you needed to charge $20 for the end product, which required delivering something big enough that readers would feel they received good value.  That whole paradigm is going away.  If the author can communicate the same idea in 20 pages, and sell online for $3, everyone is happier.  The reader saved 90% of his money and 90% of his time.  The author collects $1 or more per copy, about what he would have received for a paper book.  Everyone wins except the traditional intermediaries, the publisher and bookstore.

As an example, I built a business selling 8-page research papers into a market that was accustomed to 40 pages.  Rivals had no more content than I did, but were stretching what they had into the longer format for essentially historical reasons.  Readers aren’t dumb.  They read mine, found it had higher information density, and was thus more useful.

Similarly, Amazon is a great place to publish novelettes and shorter nonfiction, resulting in a better product than stretching to fit the traditional book format:  more succinct, faster to read, less dreck.  This means happier readers, which in the long run means sales, and thus happy authors.


Loyalty vs Objectivity

A fundamental cultural value is the relative importance of loyalty and objectivity.

To illustrate by obvious extreme, suppose your friend does something illegal.  The police stop by to ask you about it.  Do you tell all, or cover for a pal?  Your answer mostly depends upon whether you value loyalty or objectivity more highly.

Does this seem distant from your daily experience?  It’s not.  You may have no sketchy friends, but stepping away such extremes, this dichotomy is as ubiquitous as air, and as invisible.

When you argue politics, do seek to defend a party (loyalty), or explore an answer (objectivity)?

If a married friend divorces, do you side with the friend (loyalty), or with the injured party, whoever it may be (objectivity)?

This is one of those distinctions that is true at nation scale.

  • Corruption:  loyalty > objectivity.
  • Resigning due to scandal: objectivity > loyalty.
  • Property rights: objectivity > loyalty.
  • Amnesty for undocumented immigrants:  loyalty > objectivity.
  • Loosening immigration law to reflect reality:  objectivity > loyalty.

As you might expect, objectivity-based cultures appear to be more fair, egalitarian and prosperous.  Getting the right answer is really important, it seems.

“They” are “we”

In my twenties, I bicycle-camped across the United States.  People would stop me to talk.  The most common chat-starter was the excruciatingly dull, “how many flats have you had?”  More than once, a family man in his late forties opened by looking wistfully at the bike and saying, “I wish I had done that when I was 25.”

This was awkward.  These guys seemed like they were from another planet, and almost inauthentic:  obviously (to me), they could bike across America right now, if they chose.  The ride takes two months at an easy pace, and you can train as you go.  People in their sixties do it all the time.  So were these guys condescending to me?  Envious?  Or something else?

Now it’s twenty years later, and I’m one of those guys, from that other planet.  This makes it easier for me to see that they and I were never so different in the first place.  I think maybe they were just bad at small talk, or trapped by habit.  Just like me, both then and now.

I would have appreciated those chats more then if I had appreciated our similarities as much as our differences.  More generally, I think most interactions are improved and simplified when we presume they occur among a group of “us,” not “us and them.”

When you talk with a person who has no formal education, remember there is no they.  They are we.  We both love our kids, get old, fear death, enjoy sweets.  Our goals and dreams are more similar than may at first appear.  If we can’t converse easily, it might not be because we are different, but because we’re hampered by the false presumption that we are different.

When you feel weird talking to a billionaire, again remember.  Same goals and dreams, same struggles with motivation, same fears of isolation.  It is cynical to presume that the billionaire’s problems have disappeared because they are wealthy.  In fact, if you truly believe the most important things in life cannot be bought, then it would be hypocritical for you to not to empathize with someone who is rich and unhappy.  Our differences are more superficial than our similarities.

When you talk with someone much older or younger than yourself, remember that they are we.  That 80-year-old still fears isolation or not making a difference, still can’t help noticing attractive women or men, still fears making a bad impression, is still uncomfortable with small talk.  The mix changes, but the ingredients stay the same.

When the 40-year-old talks with the 20-year-old intern at the office, it can be awkward.  The awkwardness might come from both parties forgetting that they are we.  Is the 40-year old condescending, or just bad at small talk?  It could be either one.  Does he really envy the 20-year old’s youth and freedom, or is he just afraid to risk a bad impression by saying something truly revealing and non-obvious?  If he is just a fearful conversationalist, then he is just a regular person, no different from many 20-year-olds.  He is just forgetting that “they” are “we.”  And if the 20-year-old doesn’t see that, then maybe both are forgetting.

Self-discipline as a substitute for cash

Self-discipline can often substitute for cash.

  • Go to bed early => buy less coffee the next day.
  • Watch what I eat => cook at home instead of eating out.
  • Get rid of things I rarely use => eliminate need for storage unit or bigger house.

There are few situations in which more self-discipline results in more expense.

Do what’s possible, not what isn’t

As digital storage capacity grows huge, governments find they cannot maintain secrecy.

You can fit years of critical secret information on an SD card the size of a postage stamp.  As a result, leaks are asymmetric.  Attacks are vastly cheaper than defenses, and no defense is perfect.  This is inherent to the technological landscape, and there is no way to alter that landscape.

The obvious response is to have fewer secrets.

This is generalizable.  We build our goals and interests, and we even innovate, around an existing landscape of requirements and constraints.  Those constraints change over time, but are fixed in the short run.  To travel, you paddle downstream, not upstream.

Avoid Sweet Flavors

Simple dietary rule for adults:  avoid sweet flavors.

Much of the low-carb “revolution” boils down to just that.  It’s easy to get caught up in complex rules, tracking, measuring, but not everyone has time and attention for all that.

A very simple rule of thumb is just to avoid sweet flavors.

The hard part is simply noticing what is sweet, especially when your sensitivity is blunted by chronic exposure to extremely sweet flavors. But that’s a homeostatic reaction that reverses easily.  

Start by moving away from the most extreme sweets: liquid sweets like cola and juice. After a few weeks, you’ll find you are more sensitive to sweet flavors. Next, drop ice cream. You get more sensitive again. At each step, simply remove the sweetest thing, and your palate will get more and more sensitive.

Once you are really re-sensitized, certain foods you would never think of as sweet suddenly taste insanely so.  Milk.  Cereal.  Bread.  Fruit.  Even carrots.  It’s no coincidence that these foods all deliver a high glycemic load. You can taste this fact, when you are re-sensitized and paying attention.

“But what about artificial sweeteners?  they’re sweet, but low-carb.”

This misses the point on a number of levels.  First, it turns out that artificial sweeteners may actually make you fat by confusing your insulin response.  Second, and more germane to this post, if you consume something extremely sweet, you blunt your own sensitivity to sweetness, making it harder to trust your own instincts about what is sweet, and so less able to make good choices without resorting to complex rules.

Ultimately the challenge is psychological.  Do you have the wherewithal to say no to experiencing a sweet flavor?  If you do, the payoff, in self-awareness and health, is huge.

Just avoid sweet flavors.


Sleep More

100-hour weeks are the dumbest thing about otherwise-brilliant Silicon Valley culture.  They result in suboptimal quality, but worse, they waste human capital.

A recent true-life post, The Truth About What It’s Like Working For Uber, sounds like every job I had in the Valley — except the company I ran, where I could  encourage rest.

In the San Francisco Bay Area, the engineering culture for at least 40 years has promoted self-flagellating sleep deprivation.  For example, at a VC-funded software company I wrote code for in Menlo Park, our head of engineering held a contest to see which coder could sleep the least during the final weeks to our initial release.  The “winners” were basket cases for years afterward.  I took last place, sleeping an average of 5 hours a night — yet I am the only guy on that team to finish another programming project in the next 5 years.  The rest were wiped out, ruined in their mid-twenties.  This is not unusual.

Later, I ran a software company in Mountain View.  With the previous company’s death marches fresh in my mind, I gently asked everyone to leave the office by 6 or 7pm, to get some sleep.  With no death marches, we still hit deadlines, either by narrowing product scope or through clever workarounds.  We released groundbreaking mobile apps a decade before everyone else, but more importantly, we wasted no human capital:  our engineers generally went on to productive jobs elsewhere.

Programmer David Heinemeier Hansson concurs in his post, Sleep Deprivation is Not a Badge of Honor.  DHH created the Web development framework Ruby on Rails, co-founded cloud-based project management SaaS firm BaseCamp, and won the 2014 Le Mans auto race (how’s that for polymath?).  He does it on a reasonably consistent 9 hours of sleep.

Just sleep more.

Minimalist geopolitics

Global influence is won by a strong financial position. Weapons are merely a cart, pulled by horses that include tax base, borrowing capacity and GDP. These are the things that buy influence, whether through guns, elections or direct investment. (Conversely, empires collapse for lack of money.)

Nations seeking influence focus all their energy on raising their own people’s aggregate income, which increases private-sector financial strength, as well as the tax base.

This means investing mainly in education, infrastructure, public safety and rule of law, while avoiding resource drains like civil strife and, especially, external wars.

Countries that did this single-mindedly in recent decades — China, South Korea, Japan, Singapore — gained significant influence in a short time. Countries distracted by internal strife — Thailand, Malaysia — gained less. Countries that didn’t prioritize at all — the United States — lost relative influence.

Any country that is not primarily focused on increasing sustainable national income is off its game. It will lose relative influence over time. If your country under-educates its people, encourages consumer debt, and prioritizes spending over investment, it will decline. It really is that simple. We just get lost in the details.