There are still people who really don't like SENS rejuvenation research, both within and outside the scientific community. This contingent has faded over time as the funding for SENS-related research programs increased and more teams produced meaningful results in SENS-related areas such as allotopic expression of mitochondrial genes and senescent cell clearance. There are numerous research groups working on aspects of that latter project at the moment, as well as funded startup companies moving towards clinical translation of therapies. These days one has to have a very selective memory and view of the world to mock SENS, since the SENS proposals have included senescent cell clearance as a potential treatment for aging since the beginning, based on the broad range of evidence available in the scientific community even then. SENS advocates have for near fifteen years been calling for greater funding and progress in selective senescent cell destruction as one possible and plausible method of rejuvenation - and with mouse life span studies in hand now, that has been shown to be the case. Nonetheless, there are those who still propagate the irrational view that SENS isn't a legitimate part of the medical science community. One has to wonder what the true motivation is here; perhaps these people are one reason or another are uncomfortable with the idea that aging is a medical condition amenable to treatment. That seems to me a rather sad, resigned, and limited conceptual space to find oneself in, if it is the case.

You probably are not aware that, earlier this month, there was a bit of a Facebook flamewar between a few SENS opposers and some life-extensionists, some (or even all, I don't know) of whom were SENS supporters. This incident got me thinking. Why does SENS face such a fierce opposition? Why all these clearly emotional, gut-driven reactions? A lot of people over the years have raged against SENS and labelled it as quack science, a fraud, nonsense, and what you have, while having no evidence that this was the case. Sure, SENS is not fully established science yet, and who knows, maybe it will never be; we don't know for a fact. But isn't this case with tons of other research projects? Isn't the very purpose of research to establish what works and what doesn't? If SENS critics are so sure that SENS will never work, they really don't need to bother throwing challenges to disprove it and attacking it so ferociously. They could just sit back and watch as the SENS Research Foundation prove themselves wrong through their own research. On top of that, even if SENS were wrong, all the data coming from their work will certainly prove itself invaluable for future research endeavours. Win-win.

Personally, I came to the conclusion that what caused SENS to be so unpopular (at least initially) amongst the experts of the field might be its clearly stated goal of curing ageing. Biogerontologists are not immune to the pro-ageing trance by default; also, as far as I know, at the time when Aubrey de Grey first introduced SENS to the world he was practically unknown and quite new on the scene. To top it all, he was from a different field. I can see how other experts would be rather pissed at an outsider who comes out of nowhere and claims he's got the solution to a problem they mostly weren't even trying to solve. Maybe SENS wouldn't have faced any opposition if it had kept a low profile and disguised itself as mere research-for-the-sake-of-research, as it was customary in the field of gerontology back in the day.

On the other hand, people like David Sinclair and Bill Andrews too are set on bringing ageing under medical control, and to the best of my knowledge, they don't face nearly the same opposition as SENS does. Maybe it's because they followed a more traditional career path than Aubrey de Grey. Maybe their approaches are more orthodox, or maybe SENS has more media exposure and thus is more likely to be criticised. Maybe it's because of Aubrey's bold claim that the first person to reach 1000 years of age has already been born. People generally don't get this one right. He does not say that we will soon develop therapies that will make us live 1000 years. That doesn't even make sense in the context of SENS, which is a panel of therapies that would need to be periodically reapplied. What Aubrey says is that we'll probably get around 30 extra years of healthy life with the first round of SENS; during this time, perfected versions of the same therapies are likely to have been developed, granting even more extra years of healthy living, and so on. This concept is known as longevity escape velocity. I don't know for a fact why SENS faces such fierce criticism. All I know is that, quite likely, if Aubrey de Grey hadn't been shouting from the rooftops for the past 16 years that we can and should cure ageing, this tremendous problem wouldn't be receiving nearly as much attention as it does today.