And while it doesn't quite match the dollar value gains of television, the amount spent on radio and digital advertising has quadrupled.
Those figures may be evidence of a healthy and growing industry, but they also raise concerns about sometimes questionable therapeutic claims being distributed through New Zealand media every day.
Complaints cocktail
Advertising Standards Authority chief executive Hilary Souter says public complaints about purported therapeutic benefits make up the single biggest category of complaints the ASA deals with each year.
"Last year it was 25 per cent of the complaints we dealt with," Souter told the Herald.
She says complaints are "almost always" about truthful representation, with complainants criticising advertisements for making misleading or unsubstantiated claims.
A homeopath offering "scientifically proven" treatments, a skincare company claiming to treat eczema and psoriasis, and a wellness clinic trumpeting "bio-energetic screening" to identify ailments were among the latest additions to the ASA's growing catalogue of therapeutic complaints.
Those complaints were all settled and the advertisements withdrawn.
Souter says the advertisers are usually ignorant of the rules and generally remove an ad once they are made aware of a contravention.
"It's more of an education process for them," she says.
Asked about the growth in digital advertising, and the possibility that advertisers might be running non-compliant ads in online enclaves for months, Souter concedes that this is a concern. But she says that needs to be put into the context of how many people those ads are likely to reach.
"If you think about the numbers that might look at the New Zealand Herald or TV One at 6pm versus the person who searches for and then clicks on a medical service, therapy or dietary supplement ... [the latter] will in many cases be quite small."
Under the influence
One way companies make themselves visible in the vastness of the internet is by attaching their brands to celebrity influencers.
This is hardly unique to digital advertising — the late Sir Colin Meads, for example, was a long-time celebrity frontman for the deer velvet supplement Silberhorn.
The difference with modern influencers is that they don't often feature on mainstream media, instead dwelling in social media bubbles and spreading their (sometimes paid for) views among social media users who have chosen to follow them.
Charcoal-based tooth whitening polish and Tru Niagen, a dietary supplement that promises to reduce the effects of ageing, might not appear on your favourite TV or radio show, but these products have recently been flooding New Zealand Instagram feeds, thanks to influencers.
Tru Niagen, which a spokeswoman says has received Federal Drug Administration approval three times, has not been subject to any ASA complaints.
When celebrity influence is limited to such niches, it becomes more difficult to lodge a complaint — largely because the people most likely to complain aren't aware the influencer exists.
However, Souter warns against advertisers and influencers playing fast and loose with the rules surrounding therapeutic claims. "The law would apply to them [influencers] as much as to any advertiser," she says.
"The requirements don't change just because they use a social media platform as opposed to a more established channel."
As is the case in other therapeutic complaints, the advertiser will generally respond by removing the post, but by this stage, the damage is done, with the ad having already reached the target market.
Souter says that doesn't mean complaints are for naught, explaining that all ASA decisions are released to the media and advertisers are putting their reputations at stake by breaking the codes.
"The media often is more interested in a well-known influencer or a large brand than a small advertiser in a local market," she says.
Feeding on gullibility
Dr Stephen Chadwick, an ethics expert in the philosophy department at Massey University, worries that social media influencers are creating a false equivalence online in which the advice of Goop founder Gwenyth Paltrow, for instance, might be given the same — if not more — weight as that offered by a medical professional.
He says social media users aren't drawn to those who will provide the most accurate information, but rather to those who they find most interesting.
The problems start when those "interesting" celebrities leap from entertainment into giving dietary or medical advice.
While there might be strict rules about the therapeutic claims that can and cannot be made in advertising, Chadwick says the words themselves aren't the sole source of influence over the audience.
"If you have beautiful celebrity posting a picture and simply telling their audience that they used a homeopathic remedy in the morning, the inference is that the remedy played a role in making them look the way they do," he says.
Chadwick says those most susceptible to buying into this kind of influence are often vulnerable people, suffering from health issues or low self-esteem, which in turn creates a risk that someone who needs genuine medical help might choose a treatment that is scientifically unsubstantiated.
"From an ethical perspective, you have to ask how we can even allow companies to profit on these products when there is no scientific evidence that they work," Chadwick says.
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