It have heard several times that, every seven to ten years, all the cells that our body are made of have all been replaced. Example in this NY Times Article
This heartening truth, which arises from the fact that most of the body's tissues are under constant renewal, has been underlined by a novel method of estimating the age of human cells. Its inventor, Jonas Frisen, believes the average age of all the cells in an adult's body may turn out to be as young as 7 to 10 years.
Is this claim accurate?