Check out the new series of the hit Channel 4 show...

On Channel 4, Supersize vs Superskinny is back.

Host Dr Christian Jessen sets out to tackle extreme eating in the new series. With the help of two participants in each episode, he’ll highlight the consequences of over and under-eating.

Anna Richardson is also returning. She’ll examine unusual methods of losing weight by trying diets she finds on the internet – some of which go drastically wrong.

The pictures in our gallery show a sneak peek of upcoming episodes.

In the stills, Dr Christian stands alongside five pairs of overweight and underweight people. While the majority are opposite sexes, there’s one coupling which features two women.

For every photo, the participants strip down to their underwear to highlight the effects their diets have had on their bodies.

Dr Christian – who’s presented the programme since it started in 2008 – shows his authority by standing between them with his arms crossed.

In each case, the candidates know that their eating habits and lifestyle could be potentially problematic and vow to change their lives for the better.

With the help of Dr Christian, they learn the importance of a healthy and balanced diet. Firstly, they look at what their current food intake is like.

As viewers have seen previously on Channel 4, Supersize vs Superskinny takes participants to a feeding clinic.

They’re shown a large glass tube containing the average amount they consume. Some find it difficult to be faced with the truth of their unhealthy lifestyles.

The pair then move in together and swap diets in order to see how well they can survive on more or less food. Some will find it very tough to adapt to an extremely different way of living.

Throughout a 12-week process, they both work on getting healthy, fit and happy before reporting back to Dr Christian with their progress.

On Channel 4, Supersize vs Superskinny is broadcast every Tuesday at 8pm.