Louise Redknapp discovers first hand the dangers of the current obsession with being stick thin when she undertakes an extreme crash diet and exercise regime in an attempt to drop to a US dress size zero in just 30 days.

In The Truth about Size Zero, Louise undergoes a punishing plan to dramatically lose weight and attempt to drop two dress sizes. The documentary film highlights the risks of subjecting the body to such extreme measures and reveals the real effects extreme dieting and exercise techniques have on the body.

Beginning with a trip to LA to meet “Bootcamp Barry,” a military-style diet and fitness guru to Hollywood celebrities, Louise undertakes a gruelling diet and fitness regime, closely monitored by a nutritionist who highlights the dangers and side effects of crash dieting as Louise’s health begins to deteriorate.

TV presenter Louise, who was voted FHM’s Sexiest Woman of the Decade, meets celebrities who have felt the pressures to be super skinny – including Mel C and Denise Van Outen. And she talks to people from all walks of life who have been touched by the “thinspiration” trend; from magazine editors, agents, models and casting directors, to patients as young as 12 at an eating disorders clinic.

Louise says: I’ve felt that pressure to be stick thin and wanted to highlight the damage young girls can do to their bodies by subjecting themselves to punishing, unhealthy regimes in a desperate bid to lose weight. This experiment is not something I undertook lightly and by doing so I hope it helps people to see the real dangers of the extreme skinny look.

It is not glamorous or sexy in the least. Having done the plan for a month I was really relieved to be able to eat normally and healthily again. Extreme regimes such as this have a negative impact on both the body and mind. It is something I would never do again.