Everything the promoters did on one track. Everything the regulators did on the other. The chart makes a point that four pages of prose cannot: one track runs the whole width, and the other is essentially a single week in November 2012.
promotion and sale
Health Canada
evidence and official statements
What the shape shows. The upper track has entries in 2001, 2002, 2003, 2006, 2009, 2010, 2011, 2012, 2016 and 2026 — a continuous commercial history across a quarter of a century. The lower track has one early statement, then one cluster: a week in November 2012, plus a restatement in 2017 that added no new measure. Between the restatement and today there is nothing.
And note which came first inside that cluster. The evidence review was in March. The department issued nothing for eight months. A television programme aired on 27 November and the advisory followed on the 28th.
The six-year gap at the start
The lower track no longer begins in 2012. It begins in May 2006, and what is on it is not a regulator acting — it is a regulator being described as absent.
On 23 May 2006 CBC News reported that women were paying more than $200 for a temperature-based alternative to mammography. A naturopath from a company arranging thermography clinics across Canada said the scan was 88 per cent effective at finding circulation problems, and that where it showed hot areas she treated them with herbs and botanical medicine so they would not develop into a tumour. Dr. Verna Mai, then head of screening programs at Cancer Care Ontario, replied that there was no good, sound evidence that such remedies prevent breast cancer, and that women choosing thermography over mammography in the belief that the two are equivalent were being terribly misled.
She then explained why nobody was stopping it: Health Canada regulates the promotion of drugs and treatments, but not of screening tests — which made thermography, in her words, a case of buyer beware.
Six years, then nothing changed. That statement came from the official then responsible for cancer screening in the province, on a national broadcaster, and it named the gap precisely. Six more years passed before Health Canada published anything. When it did, it published a communication — which is exactly the instrument Mai had just finished explaining was not available to reach a screening test. The reason the lower track is thin is not that nobody noticed. It is that the person whose job it was to notice announced the problem in 2006 and no instrument existed to act on it.
And the warning has since been retired
Health Canada's most recent statement is the Information Update of 28 September 2017 — thermograms are not a substitute for mammograms; the devices are licensed only to measure skin temperature, similar to a thermometer; the department is not aware of any clinical evidence that they work for early detection.
That page now carries the Government of Canada archive banner. It states that the information is provided for reference, research or recordkeeping, that it is not subject to the Government of Canada Web Standards, and that it has not been altered or updated since it was archived.
What that means for the chart. The last marker on the lower track is not merely old. It has been formally retired by the body that issued it. A woman searching in 2026 finds a federal warning the department itself flags as no longer maintained, and clinic websites updated this month. The 2017 update also announced precisely what the 2012 advisory had announced — follow-up with manufacturers, and work with the Canada Border Services Agency. Five years apart, the same two measures, and no published outcome for either.
What is not on this chart, and why
We would have liked to plot the number of Canadian clinics advertising breast thermography, year by year, against the same axis. That chart is not here because the data to build it honestly does not exist in a form we can verify.
What is known is four rough points across twenty-five years: one company running mobile clinics in 2001; clinics “throughout Canada and the USA” by 2003; “dozens across Canada” in national reporting in 2012; and a single network today listing locations in five provinces and four other countries.
Two of those four are journalists' estimates rather than counts. Plotting them as a curve would give the appearance of measurement where there is none.
The honest way to build it is to enumerate archived captures of the operators' own locations pages, year by year, and count what each capture lists. That is a real method and the data is very likely there. It is a few hours of archive work, and the counting rule has to be identical for every year or the curve means nothing.
An offer. If a reader with time and an archive account wants to do that enumeration, we will publish the result and the method alongside it — including if the count turns out to be flat or falling. A growth curve drawn from the industry's own published location lists would be the single most useful thing anyone could add to this section.
Sources for the two additions
CBC News, “Unproven breast cancer screening test may steer women away from mammograms,” posted 23 May 2006. • Health Canada, Information Update RA-64636, “Health Canada reminds Canadians that thermograms are not a substitute for mammograms for breast cancer screening,” posted 28 September 2017, now held in the Government of Canada web archive. Everything else on this page is cited on the pages linked at the top.