Tag Archives: longevity

23 is not enough for me

This article in Wired explains how there is a lot more to sequencing the whole genome than just 23 genes. The cost of full sequencing has dropped to $1000, which is considered an enormous breakthrough, and it is expected to continue to fall. One company is even offering a $200 black Friday special even though they admit it is a loss leader.

Today, slightly more than a million people have had their whole genomes sequenced. Compare that to the 17 million estimated to have had their DNA analyzed with direct-to-consumer tests sold by 23andMe and Ancestry. They use a technology called genotyping, which takes about a million snapshots of a person’s genome. That might sound like a lot, but it’s really less than 1 percent of the full picture. Genotyping targets short strings of DNA that scientists already know have a strong association with a given trait. So say, for example, scientists discover a new gene that increases your risk of developing brain cancer. If that gene is not one that 23andMe looks at (because how would it know to look if the gene hasn’t been discovered yet), then you’d have to get tested all over again to learn more about your brain cancer risk. Whole genome data on the other hand, once you have it, can be queried with computer algorithms whenever a new genetic discovery gets made.

Here’s a good example of just how much more info is in a whole genome: Earlier this year, 23andMe got FDA approval to give consumers information about their BRCA1 and BRCA2 genes. More than 1,000 mutations in these genes are known to increase women’s chances of breast and ovarian cancers by as much as 75 and 50 percent, respectively. 23andMe’s test picks up the three BRCA mutations most commonly found in individuals of Ashkenazi Jewish descent, and geneticists have voiced concern that the results could leave people with a false sense of security. Veritas’ tests, on the other hand, scan for all of them and, according to the company, turn up five to seven variants of varying concern in those two genes for the average customer.

“organic” eating may lower cancer risk after all

I haven’t always been on the “organic” band wagon 100%. For one thing, the name is stupid. Chugging a glass of diesel fuel would be about as organic as you could get, in terms of the definition of the word I learned in high school chemistry. I am strongly in favor of sustainable farming practices that build soil, protect biodiversity, and prevent groundwater and surface water pollution. But in terms of health benefits, I have never felt the benefits were all that proven, and to some extent the industry is just based on scare tactics. I also wonder if the billions of humans on the planet can be fed without resorting to fossil fuel-derived fertilizer, and I still think that is dubious. But here is one large study in JAMA that did find significant evidence of a link between organic food (as labeled at the grocery store) and reduced cancer risk.

Association of Frequency of Organic Food Consumption With Cancer Risk: Findings From the NutriNet-Santé Prospective Cohort Study

Main Outcomes and Measures This study estimated the risk of cancer in association with the organic food score (modeled as quartiles) using Cox proportional hazards regression models adjusted for potential cancer risk factors.

Results Among 68 946 participants (78.0% female; mean [SD] age at baseline, 44.2 [14.5] years), 1340 first incident cancer cases were identified during follow-up, with the most prevalent being 459 breast cancers, 180 prostate cancers, 135 skin cancers, 99 colorectal cancers, 47 non-Hodgkin lymphomas, and 15 other lymphomas. High organic food scores were inversely associated with the overall risk of cancer (hazard ratio for quartile 4 vs quartile 1, 0.75; 95% CI, 0.63-0.88; P for trend = .001; absolute risk reduction, 0.6%; hazard ratio for a 5-point increase, 0.92; 95% CI, 0.88-0.96).

Conclusions and Relevance A higher frequency of organic food consumption was associated with a reduced risk of cancer. Although the study findings need to be confirmed, promoting organic food consumption in the general population could be a promising preventive strategy against cancer.

I researched the risk measures a little. The hazard risk ratio of 0.75 means that people eating mostly organic food (scoring in the top 25% of however they are measuring that) are 25% less likely than people eating the least organic food. That seems significant. From a quick skim, it appears they did try to control for differences in lifestyle (i.e., similar nutrition and exercise levels) and family history of cancer when coming to their conclusions.

September 2018 in Review

Most frightening stories:

Most hopeful stories:

  • The Suzuki and Kodaly methods are two ways of teaching music to young children that may actually help them think later in life. Training in jazz improvisation may also be good for young brains in a slightly different way.
  • There are some bright ideas for trying to improve construction productivity, which has languished for decades. Most involve some form of offsite fabrication.
  • In energy news, there’s a big idea to produce half the world’s electricity from sunlight in the Sahara desert. Another idea for collecting solar energy in otherwise (ecologically) wasted space is solar roadways, and there are a few prototypes around the world but this doesn’t seem to be a magic bullet so far. Another big idea is long-term storage of energy to smooth out fluctuations in supply and demand over months or even years.

Most interesting stories, that were not particularly frightening or hopeful, or perhaps were a mixture of both:

the old sucking the blood of the young?

There is grisly research where a young mouse is sown together with an old mouse and their blood vessels are connected. This seems to benefit the old mouse. And no, I haven’t watched “human centipede” and I have no desire to, although I did find the South Park parody of it moderately funny.

Beyond the stupidity of human centipede, you can imagine a mad dictator or Bond villain somewhere forcing people to be blood donors against their will. A more benign version would have biotech firms trying to synthesize whatever it is that makes young blood good, or possibly using stem cells to make a young version of a person’s blood. What if a version of me could be created that was just a bag of meat with no nervous system, and pumped out blood that kept me alive? That seems creepy but not necessarily unethical. Add a brain and keep that person sedated or otherwise detained against their will, and that would clearly be unethical (not to mention basically the plot of The Island.)

July 2018 in Review

Most frightening stories:

  • The UN is warning as many as 10 million people in Yemen could face starvation by the end of 2018 due to the military action by Saudi Arabia and the U.S. The U.S. military is involved in combat in at least 8 African countries. And Trump apparently wants to invade Venezuela.
  • The Trump administration is attacking regulations that protect Americans from air pollution and that help ensure our fisheries are sustainable. Earth Overshoot Day is on August 1 this year, two days earlier than last year.
  • The U.S. has not managed a full year of 3% GDP growth since 2005, due to slowing growth and the working age population and slowing productivity growth, and these trends seem likely to continue even if the current dumb policies that make them worse were to be reversed. Some economists think a U.S. withdrawal from the World Trade Organization could trigger a recession (others do not).

Most hopeful stories:

  • Looking at basic economic and health data over about a 50-200 time frame reminds us that enormous progress has been made, even though the last 20 years or so seems like a reversal.
  • Simultaneous Policy is an idea where multiple legislatures around the world agree to a single policy on a fairly narrow issue (like climate change or arms reductions).
  • I was heartened by the compassion Americans showed for children trapped in a cave 10,000 miles away. The news coverage did a lot to humanize these children, and it would be nice to see more of that closer to home.

Most interesting stories, that were not particularly frightening or hopeful, or perhaps were a mixture of both:

June 2018 in Review

Most frightening stories:

Most hopeful stories:

Most interesting stories, that were not particularly frightening or hopeful, or perhaps were a mixture of both:

  • Explicit taxes to fund wars were the norm in the U.S. right up to the Vietnam war.
  • In technology news, Google and Airbus are considering teaming to build a space catapult. The Hyperloop might be a real thing between Chicago’s downtown and airport.
  • Just under 0.1% of migrants crossing the U.S. border are members of criminal gang such as MS-13. About half of border crossers are from Mexico while the other half are mostly from Honduras, Guatemala, and El Salvador. Some are fleeing violence or repression, while others are simply looking for economic opportunity.

life expectancy in ancient societies

This article says life expectancy in ancient societies may not be as low as people tend to think. Many people are probably aware that child mortality brings down the average, but something I never thought about is how hard it is to measure the upper limit for populations that existed before any type of written records. There are people who specialize in digging up graves and doing exactly this, which seems a bit macabre.

We are all able to instinctively label people as ‘young’, ‘middle-aged’ or ‘old’ based on appearance and the situations in which we encounter them. Similarly, biological anthropologists use the skeleton rather than, say, hair and wrinkles. We term this ‘biological age’ as our judgment is based on the physical (and mental) conditions that we see before us, which relate to the biological realities of that person. These will not always correlate with an accurate calendar age, as people are all, well, different. Their appearance and abilities will be related to their genetics, lifestyle, health, attitudes, activity, diet, wealth and a multitude of other factors. These differences will accumulate as the years increase, meaning that once a person reaches the age of about 40 or 50, the differences are too great to allow any one-size-fits-all accuracy in the determination of the calendar age, whether it is done by eye on a living person or by the peer-preferred method of skeletal ageing. The result of this is that those older than middle age are frequently given an open-ended age estimation, like 40+ or 50+ years, meaning that they could be anywhere between forty and a hundred and four, or thereabouts.

The very term ‘average age at death’ also contributes to the myth. High infant mortality brings down the average at one end of the age spectrum, and open-ended categories such as ‘40+’ or ‘50+ years’ keep it low at the other. We know that in 2015 the average life expectancy at birth ranged from 50 years in Sierra Leone to 84 years in Japan, and these differences are related to early deaths rather than differences in total lifespan. A better method of estimating lifespan is to look at life expectancy only at adulthood, which takes infant mortality out of the equation; however, the inability to estimate age beyond about 50 years still keeps the average lower than it should be.

Archaeologists’ age estimates, therefore, have been squeezed at both ends of the age spectrum, with the result that individuals who have lived their full lifespan are rendered ‘invisible’. This means that we have been unable to fully understand societies in the distant past. In the literate past, functioning older individuals were mostly not treated much differently from the general adult population, but without archaeological identification of the invisible elderly, we cannot say whether this was the case in non-literate societies.

China passes U.S. in healthy life expectancy

  1. U.S. citizens still live a bit longer than Chinese citizens on average, but Chinese citizens have drawn even and slightly surpassed us in health.

https://www.axios.com/chinese-people-now-healthy-longer-than-americans-6dc7235f-e057-45ee-a975-c433611edabf.html

This would be perfectly fine if it just represented China catching up, but I suspect it represents the U.S. stalling as both our peers and developing countries continue to progress.

brain uploading

Good news – instead of killing you, slicing up your brain, freezing it and keeping it on ice so they can revive your consciousness centuries in the future, scientists might now be able to scan your brain and just store the pattern for later use. The bad news – they still have to kill you, slice up your brain, and freeze it first before they do the scanning. And of course there is still the old Star Trek transporter problem – when they save your pattern, disintegrate your matter, and recreate the pattern somewhere else using new matter, is it really still the same you, or is it a different you with the same memories as the original you? The new you won’t know the difference, and you won’t know the difference either because you won’t exist, so does it matter? Well, the technology still has a ways to go before we really have to worry about any of this. If they can ever find a way to save a detailed copy of your brain without killing you first, there would be very little downside to trying it. And before you ask, yes, I have read the book Altered Carbon, and no, I have not seen the new show Altered Carbon.