Despite its prime 7.30pm slot, it failed to crack the top 30, and was beaten by Great Continental Railway Journeys on SBS and ABC's The Indian Dream Hotel on Tour.

Ten has already bumped the show from Sundays, replacing it with Modern Family and Bull.

Loser now airs Mondays to Thursdays.

The network had high hopes for the revamped series, which promises holistic mind-body transformations to its contestants.

But some viewers are sceptical, questioning why contestants as small as 78-kilogram Nikki need to lose weight.

In an interview with Fairfax Media, trainer Shannan Ponton accused these critics of "reverse fat-shaming".

Ponton said: "From what I can ascertain on social media, most of the backlash is coming from overweight people ... the judged are now becoming the judges ... overweight people are looking in and judging other people."

The show got off to a bad start, averaging 450,000 city viewers on its March 14 debut. And it has struggled to keep those viewers.

Previous seasons - which depicted contestants crawling through mud, tempted with junk food, and being screamed at by trainers - drew bigger audiences.

In the five major cities alone, including time-shifted audiences, those seasons averaged:

2006: 1.33 million

2007: 1.17 million

2008: 1.13 million

2009: 1.08 million

2010: 837,000

2011: 1.05 million

2012: 887,000

2013: 774,000

2014: 460,000 (program was shifted around to accommodate Sochi Olympics.)

2015: 643,000

2016: Program was "rested".

Of course, many factors are at play here. Networks are fracturing their audiences across an expanding array of multi-channels, while new competitors such as Netflix and Stan* steal some away. And overnight ratings are only part of the story.

This season's debut grew from 450,000 to 573,000, after a week's worth of time-shifted and online viewing were added. Regional figures will boost this number again, as will any further viewing that occurs within 28 days of the initial broadcast.

Still, Loser is struggling against the might of Seven's My Kitchen Rules, which won Tuesday night with 1.24 million viewers. Nine's Married at First Sight, enjoying its best season yet, ranked fifth (1.03 million).

The results are a blow for Ten, which is encumbered by costly output deals with CBS and Fox. Yet many viewers tend to record and watch American programs at their convenience - or simply pirate them - reducing their value to the network.

In its favour, Ten has the youngest audience.

According to OzTam data its executives presented at Screen Forever, the average age of its viewers is 44. This compares to 66 for ABC; 61 for SBS; and 52 for Seven and Nine.

Right now, Ten just needs more of these younger viewers.

The network has been approached for comment.

*Stan is part-owned by Fairfax Media, owner of this masthead.