Mother of four Jennifer Irvine is ‘obsessed with longevity’. Given that she’s only 42 and a picture of blooming, bouncing health, that seems a tad premature. But Jennifer and her friends talk about it a lot, she tells me. ‘Life is a series of chapters. I came through purple hair, a nose ring and friends overdosing in my 20’s to being a wife, mother and businesswoman. Now we all want to reach that certain âge – as the French say – still glowing, feeling great about ourselves and able to enjoy life.’