Critical reception was largely favorable. It was named a best book of the year by more than 60 media outlets, including New York Times, Oprah, NPR, and Entertainment Weekly. Lisa Margonelli reviewing in The New York Times Book Review said:
Skloot narrates the science lucidly, tracks the racial politics of medicine thoughtfully and tells the Lacks family’s often painful history with grace. She also confronts the spookiness of the cells themselves, intrepidly crossing into the spiritual plane on which the family has come to understand their mother’s continued presence in the world. Science writing is often just about “the facts.” Skloot’s book, her first, is far deeper, braver and more wonderful.
Dwight Garner of The New York Times wrote:
I put down Rebecca Skloot’s first book, “The Immortal Life of Henrietta Lacks,” more than once. Ten times, probably. Once to poke the fire. Once to silence a pinging BlackBerry. And eight times to chase my wife and assorted visitors around the house, to tell them I was holding one of the most graceful and moving nonfiction books I’ve read in a very long time …It has brains and pacing and nerve and heart.
One reviewer for The New Atlantis, while mostly positive about the book, questioned its ethical arguments about tissue markets and informed consent, and claimed to have found factual errors: one related to the role of HeLa cells in early space missions, and, another related to a statement in the book that says "if all HeLa cells ever grown could have been gathered on a scale, their total weight would have measured more than 50 million metric tons. Skloot addresses this question on her website, where she explains how the 50 million metric tons figure was calculated, saying "That calculation was based on the way HeLa cells are known to divide (specifically how often they double their numbers) and the amount of time they’d been alive at the time the calculation was made." She clarifies that "it was a hypothetical calculation because that many cells couldn’t have been saved and put on a scale." She also says that the figures "were verified before the book went to press by the scientists who did the original calculations, and outside experts." 
The book was awarded the National Academies Best Book of the Year Award, the American Association for the Advancement of Science's Best Young Adult Book Award, The Wellcome Trust Book Prize, awarded annually to an outstanding work of fiction or non-fiction on the theme of health and medicine. It also won the Heartland Prize for non-fiction, among others, including a Salon Book Award, and a 100 New York Times Notable Books of the Year. The paperback edition had spent 75 weeks on the New York Times Best Sellers list.
The book was adopted as a common reading text at more than 125 universities and was widely taught in high school, undergraduate, graduate and doctoral classrooms.