This is crap because of how misleading it is. For example yes a correlation exists between metabolic activity and lifespan across a wide range of life forms, but humans just like most birds are at the extreme edge.<p>So, as humans already have rather extreme lifespans relative to most organisms meaning our bodies are likely already using the low hanging fruit in terms of extending lifespans. But, without that context it seems like birds have some advantages we could copy.<p>This then hidden by first referencing a U shaped curve and ‘our place’ on it without clarifying it’s a metabolic curve not a lifespan curve.<p>Finally “In a 2007 analysis it was shown that, when modern statistical methods for correcting for the effects of body size and phylogeny are employed, metabolic rate does not correlate with longevity in mammals or birds.”
Mitochondrial dysfuction comes primarily from manganese being replaced by iron, from the wrong Fe/Mn ratio (which the body has no way of correcting, as both are absorbed by the same mechanism and iron cannot be excreted.) or a deficiency in general, which results in mismetallation.<p>E-coli has a similar problem with iron/manganese/zinc: <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4192467/" rel="nofollow">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4192467/</a><p>The general problem with iron is that while it is faster, it's also reactive in its free form, unlike manganese, which only works in proteins.<p>The majority of the world population is supposedly iron deficient, but the numbers are likely based on populations that already suffered from iron overload; it is possible that animal lifespans were substantially shortened as the result of human activity which disrupted the mineral balance to the degree no animal evloved to deal with.
IMHO longevity is overrated. I would put importance of fighting age-related diseases (including tissue aging, immune and hormonal decline in particular) well above extending longevity in importance. I certainly don't want to live 200 years looking and feeling what is considered adequate to being this old but looking and feeling like a 25-35-years-old until I reach something near the age of 60 (of course longer is kind of better perhaps but if I had to - this is what I'd trade) and die quickly and easily without going through even slightest form of disability (defined by comparison to healthy young adults) and physical struggle seems like something I'd totally buy into.
Lifespans depend on far more than just one thing, but multiple. Telomere shortening is a contributor, mitochondria may be, senescent cells, stem cell death, mechanical issues like joint or tooth wear down (partly coped in humans for now but very much an issue in other animals especially mammals which for some odd reason, in general don't have constantly regrowing teeth), etc etc.
But count we are really mitochondrians- a hundred times as many of them inside us as human cells. So human cells are really just vessels for mitochondria to make nore mitochondria with a bit of embelishment on the side.
>But if the conditions are unfavorable, if we’re starving, there’s a kind of switch from gearing up for sex and protein synthesis and bulking up to gearing up for survival: battening down the hatches and waiting out the bad times. This genetic switch has been the focus of most work on aging over the last decade or so.<p>Pure speculation, but based on its pervasiveness, I've wondered if depression could have been selected for through a mechanism such as this.
><i></i><i>So if I focus all my resources on having sex, then effectively I take resources away from longevity. I take them away from surviving for longer, and so I shorten my lifespan almost deliberately in evolutionary terms.</i><i></i><p>This is a very interesting statement - in some of the Esoteric Teachings I have read throughout my life - they specifically say that masturbation for simple pleasure (ejaculation in males) -- drains you of your life essence and is seen spiritually as a selfish-wasteful use of your life - and this shortens your lifespan and reduces your spiritual power. (additionally, doing very deliberate things with sexual energy is a basis in sex magick)...<p>The idea being that you're pulling life-force from yourself and then 'projecting' intentionally toward what you're doing with that sexual energy -- which would be interesting if you were draining energy from mitochondria in general.