Body fat is a source of shame for many people, something to be hidden, fought, and burned away. But fat, says the biochemist Sylvia Tara, isn’t just unsightly blubber, it’s an essential and deeply misunderstood organ that’s vital to our existence. It enables our reproductive organs, strengthens our immune system, protects us from disease, and may even help us live longer. In a new book, Tara explores the science behind our least appreciated organ, and she joins us Wednesday to talk about it.

Sylvia Tara holds a PhD in biochemistry from the University of California, San Diego, and an MBA from the Wharton School of Business. Her new book is called The Secret Life of Fat: The Science Behind the Body's Least Understood Organ and What It Means for You [Amazon|Independent bookstores].