Hello and welcome to the History Hour Podcast from the BBC World Service with me Max Pearson,

the past brought to life by those who were there.

This week how the World Health Organization finally came to realize that obesity was and is a global problem.

It was recognized that there were some fat ladies who found difficulty in slimming.

All the doctors thought this was a ridiculous problem. Was it really important for health?

Plus we'll get an insight into life in the White House in the 1930s.

We'll look at the birth of an African film industry and the immortal cells of Henrietta Lax,

a truly remarkable story of one woman's impact on medical research.

I said, you're working on her cells? And he said, said yeah he says her cells are still alive and I just I was just truly amazed and he said he'd been working on her for years

That's all to come but we begin with one of the most well-known figures of the 20th century,

while history is littered with political and military leaders who stand out as remarkable

for how they stamp their mark on the world around them, far too often through violence and intimidation,

there are far fewer who are emblematic of a charitable approach to their fellow human beings.

Mostly the quiet and the giving just don't make it into the history books, with

one or two exceptions. And Mother Teresa is certainly one of those exceptions. It's 20 years

since the pioneering Roman Catholic nun retired from her work with the poor of Calcutta,

shortly before she died at the age of 87.

Last year Pope Francis declared her Saint Teresa of Calcato.

She may have been saintly, but not all those who came into contact with her agreed with her methods.

Rebecca Kessby has been speaking to a woman who used to volunteer at the Mother Teresa orphanage.

It was here in the streets of Calcutta that Mother Teresa started her work.

Now her sisters, with their simple blue and white saris, their hallmark, have taken it to nearly every corner of the world.

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