He says most fail to deliver the results they promise, and is pursuing them through a Government agency that has the power to make them cut the big claims.

Already one high-profile product is under investigation.

From tablets to powders and even sprays, the world of ‘complimentary medicine’ has it all – quick-fix solutions, preying on the vulnerable.

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In many cases though, what they promise is actually far from possible.

Do you like eating fast food but can't afford the calories? Apparently there's a pill for that. It's called Undoit - but does it do anything?

Or how about busting that hunger or giving your metabolism a kick? The sprays and tablets for that claim to be 100 per cent natural, yet scientifically formulated - is that even possible?

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Medical scientist Dr Ken Harvey from Latrobe University doesn't believe a word of these claims, and he's lodged several complaints against a number of companies.

“Pills don’t work and you are wasting your money,” Dr Harvey said.

A complaint from Dr Harvey resulted in Chika Health Products’ Suprexxa Hunger Buster, Metabolism Kick and Fat Burner Maxx - all owned by former New South Wales's Liberal Leader Kerry Chikarovski - being investigated by the Therapeutic Goods administration.

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If Chika Health can't prove that their products "support metabolism and muscular performance" as claimed, they'll be banned.

Chikarovski wouldn't speak on camera while awaiting the TGA hearing, but says she stands by her products.

Michael Romm from Undoit was happy to spruik his pills’ magical calorie-cancelling powers, saying “we also have thousands of our customers calling us and writing us to say that it really works, and they wouldn’t keep buying it unless it actually worked.”

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Diet cures are big business. The companies behind these ‘miracles’ share a $1 billion pie, and often get away with their outrageous claims because the complementary medicine industry is virtually self-regulated.

To sell a product you have to be listed on the Australian Register for Therapeutic Goods. That's as easy as going to a website, entering your ingredients, and what your product delivers.

“We're very confident that we have enough evidence to satisfy the TGA that our product Undoit works very safely, and is very effective,” Romm said.

According to The Australian Medical Association's Dr Steve Hambleton “the market is being flooded with lots of shonky products.”

Only if there is a complaint are the claims ever investigated. “The TGA simply makes sure that the manufacturing process is appropriate, they make sure that there are no ingredients that are dangerous, but that's the only threshold - they're not tested,” he added.

So there's no guarantee they work.

Dietician Mark Surdut says the only way to lose weight is tried and true – eat less calories and exercise more. “It’s just not possible to take a tablet, or two tablets, or five tablets, to neutralise that sheer quantity of calories in food,” he said.

“These products are certainly not the answer. Discuss it with your health professional before popping a pill," he concluded.

• The Nutritionist - www.thenutritionist.com.au