Earlier this month, a public memorial service was held for Jessica Ainscough. At the time of her death on 26 February she had cultivated a large online following due to her use of alternative therapies to treat an exceedingly rare form of cancer, epithelioid sarcoma. Driven, personable and telegenic, she was known as ‘The Wellness Warrior’. Regardless of the extent of her illness, which, at times, impelled her to hide her cancerous left arm, in virtually every photograph and video blog she radiated a quintessentially Australian healthfulness – blonde and bronzed and all-natural. She seemed to sing of the sun and the beach, of both hard work and hard play.

Then, of course, there was the fixed smile, lips parted over whiter than white teeth in a sort of permanent invitation, a doorway into an enviable life beyond suffering, beyond the ordinary failings and frailties of the human body. It was a smile that was worn like a mask whose only guarantee against slipping was the implacable belief that it won’t.

Ainscough placed her faith not in, to paraphrase her own words, Baby Jesus, Buddha or Elvis, but a delusion with a patina of medical legitimacy: Gerson Therapy. Developed by German doctor Max Gerson in the 1920s, Gerson Therapy is, in essence, a diet and ‘detoxification’ program that calls for its adherents to consume an implausible amount of fresh fruits and vegetables – potentially more than ten kilograms a day – and numerous supplements, in addition to undertaking regular coffee enemas.

During the two years Ainscough subscribed strictly to Gerson Therapy she was, daily, drinking thirteen fruit juices and giving herself up to five coffee enemas. Other writers, especially surgical oncologist David Gorski, have unpacked the full speciousness of such a regime as a treatment for cancer and other degenerative diseases in a way I won’t attempt to paraphrase here. It’s enough to say that Gerson Therapy has few rivals in the field of long and thoroughly discredited medical quackery.

And yet, like all truly bad ideas, it has proved zombie-like in its ability to rise from the grave again and again. Perusing the official website of the San Diego-based Gerson Institute, I was struck by testimonials of ordinary people. ‘Carla received a death sentence in 1958,’ read one, ‘yet 54 years later she is in vibrant health, thanks to the Gerson diet!’ In the accompanying photograph, a glowing, grinning Carla poses at a farmers’ market with a miraculous tomato. She looks, of course, great for her age.

We will never know what Jessica Ainscough would have looked like in her seventies. She was just 30 when she died. According to Gorski, she may, though it’s not certain due to a paucity of data, have halved her chances of living another ten years by not assenting to surgery. ‘The way I saw it,’ Ainscough explained in 2012, ‘I had two choices. I could let them chase the disease around my body until there was nothing left of me to cut, zap or poison; or I could take responsibility for my illness and bring my body to optimum health so that it can heal itself. For me it was an easy decision.’ The alternative that may have added years to her life, and that Gorski describes as the ‘one good shot’ she didn’t take, was to have her arm amputated. The truth is that, when it comes to cancer, there is no such thing as an easy decision.

There are few aspects of our lives that seem as intensely personal as the choices we make regarding our health and that of our loved ones: what we eat, how often we exercise, where we choose to go to bring our babies into the world or mend our broken bodies and minds. We are often encouraged, and, I think, are becoming increasingly used to thinking of the accumulation of these choices as a ‘journey’, a personal odyssey of self-realisation that has nothing whatever to do with anybody else’s.

‘HER story’. ‘HER journey’. Variations on these words, that shouty personal pronoun often present, have been popping up all over comments sections on online articles about Ainscough’s death. It’s a way, in part, to shut down debate about Ainscough’s advocacy of ‘natural healing’ modalities but it speaks to something else as well: our increasing, almost evangelical privileging of our responsibilities to ourselves over those in our neighborhoods and communities. The irony is that this tearing up of the social contract is, in essence, more neoliberal than hippy: ‘There is no such thing as society’.

Nowhere at present is this individualism more visible than in affluent North America – Marin County (SF) and Orange County (LA) in particular – where more and more parents are electing to under-vaccinate or not to vaccinate their children. The incidence in California of pertussis (whooping cough), a disease that had almost been eliminated since its 1950s peak thanks to successive vaccines, is now approaching the proportions of a full-blown outbreak. Just six Americans died from the disease in 1995; last year, more than a thousand cases were recorded in California alone. Nation-wide, measles rates are at a twenty-year high.

Pertussis is incredibly communicable: one case can lead to a dozen secondary transmissions. It is also, though our success in combating it has largely erased the fact from cultural memory, far more serious than just a distinctive cough. As infectious disease specialist Dr Jeffrey Bender told the Hollywood Reporter last year, patients ‘cough so hard, it turns into vomiting and broken ribs; they end up intubated, to ventilate their lungs’.

These horrific symptoms are what parents who fail to fully vaccinate their children are complicit in passing on, and that’s not all – herd immunity is weakened, and the risk to the very young and immunocompromised is increased. As is often pointed out by critics of anti-vaxers, it is, perversely, thanks to the protection provided by herd immunity – by, in other words, the community – that the luxury of opting children out of vaccination programs is an option. Yes, we are all on our own journeys, but the freedom to determine their courses, while a bedrock of our democracies, must not be exalted at the expense of a simple, essential truth: we do not walk alone.

This brings me back to Jessica Ainscough, a woman whose impressive social and mainstream media profiles, both assiduously cultivated, ensured that her choice and approval of unscientific cancer treatments did not exist in a vacuum. She appeared on breakfast television. She published books and gave speeches. And while she claimed – and segments of her credulous fanbase continue to claim – that she never said that Gerson or any other alternative health protocol succeeded in curing her of cancer, the evidence is far less clear-cut.

It is, unlike the issue of anti-vaccination, impossible to quantify the effect of Ainscough’s highly public advocacy of pseudoscientific remedies. We will simply never know how many of, and in what ways, Ainscough’s tens of thousands of admirers have absorbed her beguiling rejection of conventional medicine in the face of profound illness. She was a victim too – diagnosed with an uncommon and aggressive form of cancer at 22 – and this fact should give Ainscough’s most strident critics cause for reflection. But who, in good faith, would argue that the unknowability of Ainscough’s legacy is a comfort?