Least you could have done is put a hyperlink to this thread to save me the exhaustive search for it.
https://www.worldometers.info/demographics/life-expectancy/
UK is 37th ranked country, US 48th. There is probably a genetic factor in there as the top three are all Asian, but extracting that from differences in nutrition is probably difficult. There are also probably one or two questionable data sets (e.g. French Polynesia - both a small sample size and in a part of the world with the highest obesity rates, so the official stat doesn't look credible to me).
But if you look at how we compare to much of Europe and Australia, it isn't good at all.
I also wonder about "healthy" life expectancy and whether there are any measures of that. I'd rather live to 82 riding a bike and then drop dead, than have my legs amputated and go blind from diabetes but struggle on until 85. I suspect the UK does horribly on any such measure also, given that 20% of the working age population appears to be too ill to actually do anything.