When considering whether to do something, do you ever consider the risks? If you knew that one activity would certainly bring an immediate end to your life, you probably would not be very inclined to proceed. If, on the other hand, it would only reduce your life expectancy by a day, you might be willing to assume the risk. How much is each day of life worth to you?

While we cannot know with certainty how long any of us have remaining on this earth, there are some ways of calculating what effect an activity will have on your anticipated life expectancy. Welcome to the wonderful — and decidedly morbid — world of micromorts and microlives.

Micromorts — May The Odds Be Ever In Your Favor

A micromort is a unit equal to one-millionth of the probability of death. The more you have, the more likely you will meet your demise.

One way to understand this is to picture playing a game of Russian Roulette. Since we aspire to be family-friendly, here at Commonplace Fun Facts, let us stress that there is nothing fun about this “game.” It is a profoundly stupid, idiotic, and utterly-dumb thing to do, so we definitely do not recommend you try this. The example is offered for illustration’s sake, only.

In the traditional Russian Roulette, a person puts one bullet in a six-chamber revolver and spins the chamber before holding the gun to the head and pulling the trigger. There is one chance out of six that the bullet will be in the firing position. Although it is possible that the first time you pull the trigger it will generate a loud bang, statistically, it isn’t super likely. At one chance out of six, there is a 16% probability of it occurring.

There are two ways to increase the likelihood of being rewarded with a bang that will end your time on this planet. You can add more bullets to the chamber or pull the trigger more than once. With each added bullet and with each pull of the trigger, the odds of hearing “BANG!” increase by another 16%.

We repeat: Russian Roulette is a really dumb thing to do. Would you really want to risk your life, knowing that there is “only” one chance out of six that pulling the trigger will end your life? No reasonable person would be likely to take that risk, no matter what reward is offered as an incentive to do so.

Suppose, however, that your revolver had room in the chamber for 1 million bullets. Each time you pull the trigger, there is one chance out of a million that it will find the bullet. With those kinds of odds, you might entertain taking a risk if the potential reward was worth it.

You can think of micromorts as bullets for that massive chamber. Although there is a chance that any time you pull the trigger the gun will go off, it is highly unlikely. The way you can increase the likelihood is to add more bullets (micromorts) or to pull the trigger more frequently (repeat the activity in question).

How this translates into real-world application begins with figuring out what it means for you. Step one is determining your ordinary life expectancy. When you begin to do this, you quickly realize that some of us have been dealt a better hand based on where we were born and which gender we are. According to this chart, a male born in Hong Kong can expect to live 82.2 years. His female counterpart can plan on 88.1 years. A boy born in the USA can plan on 76.3 years, while a girl can expect 81.4 years. Figure out for yourself which number applies to you. For purposes of illustration, let’s go with a global average of 70.6 years for a man. That equates to 25,769 days. Divide 1 million by 25,769, and you get 38.8. This is the number of micromorts for each day of life or 1.61 micromorts per hour.

In other words, for each hour that you live, you are adding 1.61 bullets to your million-round chambered gun. By doing nothing more than living out your day, you are playing Russian Roulette with nearly 39 bullets — any one of which could go off with the next pull of the trigger.

The good news is that the micromorts reset with every risk period. The risk period is whatever length of time you choose to analyze. If you are wanting to know your risk of death from living a single day, the risk period is 24 hours. That means that when you add the 37th bullet to the chamber at 11 p.m. tonight, you just have to sweat it out for another 60 minutes before adding the 38th bullet at midnight and quickly unloading all of those micromort bullets to start the day over. If, however, you are wondering about your odds of getting through an entire week, you will accumulate 271.6 bullets over those seven days before you get a chance to unload your death probability gun.

Although all of us have 24 hours in a day in common, it is how we spend that time that really makes a difference. Your activities during the risk period also affect the number of micromort bullets in your gun.

Let’s suppose the risk period under consideration is one week. The week will be a fun-filled vacation in which you drive 460 miles to New York City, where you spend two days playing 10 games of (American) football with some buddies. You then fly 3,000 miles to go skiing for one day. The next day you fulfill a lifelong dream of going skydiving. The next three days you relax and do little more than go swimming each day.

As we’ve already explained, you can plan on ending the week with 271.6 micromorts, accumulated from simply maintaining your heartbeat for seven days. Each of your vacation activities also earned you some micromorts:

• Driving 460 miles — 2 micromorts
• Spending 2 days in New York City — 1 micromort
• 10 games of football — 200 micromorts
• Flying 3,000 miles — 3 micromorts
• One day of skiing — 1 micromort
• Skydiving — 10 micromorts
• 3 times of going swimming — 36 micromorts

The 253 micromorts from your activities, added to the 271.6 micromorts earned by living through seven days, means you ended your week with 524.6 micromort bullets in your mortality probability gun. In other words, you have just under 525 chances out of one million that your fun-filled vacation week would be your last.

To be as accurate as possible, you would need to add in the micromorts earned from all of your activities. Some examples would include:

• Climbing Mount Everest — 37,932 micromorts per attempt
• Mountaineering in the Himalayas — 12,000 micromorts
• Being infected by COVID-19 — 10,000
• Being infected by the Spanish flu 3,000
• Getting out of bed (age 90) — 463 micromorts
• BASE jumping — 430 micromorts
• Being born (your first day of life) — 430 micromorts
• Giving birth (Caesarean) — 170 micromorts
• Scuba diving (per year) — 164 micromorts
• Giving birth (vaginal) — 120 micromorts
• Getting out of bed (age 75) — 105 micromorts
• Using heroin — 30 micromorts
• Playing American football — 20 micromorts
• Getting out of bed (under age 1) — 15 micromorts
• Going for a swim — 12 micromorts
• Riding a motorcycle 60 miles — 10 micromorts
• Skydiving — 10 micromorts
• Flight on a hang glider — 8 micromorts
• Running a marathon — 7 micromorts
• Getting out of bed (age 45) — 6 micromorts
• Scuba diving (per dive) — 5 micromorts
• Diving – 4.72 micromorts per dive
• Rock climbing — 3 micromorts
• Horseback riding — 0.5 micromorts
• Kangaroo Encounter — 0.1 micromorts
• Landing on the moon — zero micromorts

As you can see, not all activities are equal. You could spend a nonstop week of skydiving and have to jump out of a plane 3,793 times before accumulating the micromorts you would get from one time of scaling Mount Everest.

Micromorts are calculated by examining the number of deaths experienced by the class of individuals who performed the particular activity. For this reason, running a marathon is considered riskier than landing on the moon. The rationale for this comes from the fact that a lot of people run marathons, and a few happen to die from the experience (26 deaths out of 3,292,268 participants, according to this study). In contrast, twelve men have walked on the moon, and none of them died from the experience.

We should not conclude, therefore, that all activities on the list are necessarily beneficial, based solely on micromorts. Unquestionably, you are better off as a 75-year-old to choose to get out of bed in the morning, rather than to take heroin, even though the first will earn you 105 micromorts, as opposed to heroin’s 30. The reality is that no one takes just one dose of heroin because of its addictive qualities, and since it tends to coincide with any number of additional unhealthy life choices, you will rarely find a 75-year-old heroin addict.

On the other hand, it should be noted that by the time you are 90 years old, you gain 463 micromorts just from the risk of getting out of bed in the morning. With BASE jumping earning you a comparatively-paltry 430 micromorts, why not sleep on the edge of a cliff and take your first step of the day by throwing yourself into the air with a parachute?

With this in mind, you can evaluate certain activities and not only decide which is likely to be safer but you can also better judge whether the reward is worth the risk. Consider the following activities, each of which is statistically an equally risky 1 micromort apiece:

• Eating 40 tablespoons of peanut butter (due to aflatoxin)
• Eating 100 char-broiled steaks (due to benzopyrene)
• Living two days in New York City or Boston (due to pollution)
• Spending 1 hour in a coal mine
• Eating 1,000 bananas (due to radioactive potassium-40)
• Traveling 6,000 miles by train (due to accident)
• Traveling 1,000 miles by jet (due to accident)
• Traveling 230 miles by car (due to accident)
• Walking 20 miles (due to accident)
• Skiing for one day (due to accident)
• Living 2 months with a smoker (due to cancer, heart disease)

Granted, you are unlikely to be affected by chowing down on 40 tablespoons of peanut butter or 1,000 bananas at one time, but this list does point out the comparative risk of travel by car, jet, and train.

Please also keep in mind that micromorts accumulate for the risk period under analysis. True, you probably will not have to worry about eating 1,000 bananas if you are only looking at your risk of death for one day. If, however, you are trying to figure out the odds of your demise over 25 years, and you have eaten 100 bananas a year, then you cannot overlook the 2.5 micromorts your banana obsession has cost you.

Let’s Talk About Microlives

Similar to micromorts is a unit known as the microlife. It is defined as a unit of risk representing a 30-minute change in one’s life expectancy.

Microlife analysis also looks at different activities, but unlike the micromort, microlives are cumulative over a person’s entire lifetime. The only resetting occurs when the doctor pronounces you dead.

The nice thing about talking about the microlife is that it isn’t all about shortening your life expectancy or increasing your chances of death. Many activities add microlives, thus lengthening the amount of time you can expect to spend on this planet.

Like the micromort, you are going to take a hit in the microlife department every day, regardless of what you do. By definition, each 24 hour period costs you 48 microlives. By the same token, some of us get positive microlife benefits without having to lift a finger. Are you female? If so, you gain 4 microlives every day, simply by being unencumbered by that pesky Y chromosome.

To put that in context, if a boy and a girl are born on the same day and live under the same conditions, after one day, it will be as if the boy aged 24 hours, but the girl will have only aged 22 hours.

In the realm of microlives, here are a few examples of things that will shorten your life expectancy:

• Smoking 15-24 cigarettes — loss of 10 microlives
• Obesity (per 5 units above BMI of 22.5 each day) — loss of 3 microlives
• Eating 3 ounces (85 grams) of red meat — loss of 1 microlife
• 2 hours of watching television — loss of 1 microlife

On the flip side, you can prolong your life expectancy with some of these activities:

• Eating 5 servings of fruits and vegetables — a gain of 4 microlives
• First 20 minutes of moderate exercise — a gain of 2 microlives
• Each additional 40 minutes of moderate exercise — a gain of 1 microlife
• 2-3 cups of coffee — a gain of 1 microlife

There are some tools to help you evaluate the overall health of your lifestyle and to roughly calculate when to plan your funeral. One tool is the Risk Navigator App.