Can you imagine sitting down to a breakfast of raw beef liver? Or existing on fruit and nothing else for dinner?
It is not a form of rapid weight-loss or extreme detox, it is actually the way some people choose to live every day of their lives.
We met two extreme eaters who both believe in tucking into food in its uncooked state.
More info: The SOS desperation diet
While Anne Osbourne eats nothing but fruit, Scott Wheeler's diet consists predominantly of raw meat.
"I'm the odd one out - socially it can be a difficult diet to maintain," Scott said.
For almost five years, Scott has been eating around 1kg of raw meat every day.
He believes that is the best way to get the maximum enzyme content of the food, which helps metabolic function.
Not a morsel of food passes his lips just because it tastes good.
"I can enjoy a piece of raw beef liver, not for the taste but for the nutritional qualities and the nutritional benefits," he said.
Related story: Low GI kick-start diet
Anne Osbourne does not eat meat, dairy or grains.
"It's not just for the health, it's not just for the environment it's for the wellbeing of creatures and plants," she said.
"It's all of them combined."
Read more: Here are some low GI recipes
Dietician Susie Burrell is sceptical about both of these lifestyles.
"Fruit has literally no protein in it, no essential fatty acids, no iron, no zinc, no calcium, all those essential nutrients we need," she said.
"There's no science behind eating raw meat and showing that's in fact better, there's no science to show that unpasteurised dairy products are better."
Today Tonight developed the Kick-Start diet. Visit our extensive diet resource here.
Concerns over weird diets
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