[1] Tangstad fought Michael Spinks for the IBF Heavyweight title on 6 September 1986, losing as a result of a fourth-round knockout.

He retired with a career record of 24 wins (14 by knockout), 2 losses and 2 draws.

After retiring from the boxing ring, Tangstad began a career in Norwegian television[3] and was the CEO of the now defunct "Modern Sports & Events" (MSE),[4] which was licensed to broadcast UFC pay-per-view events in Scandinavia.

Tangstad died after a long illness on 26 June 2024, at the age of 65.

[8] He had been struggling with peripheral neuropathy, and had lost the use of his hands, arms and legs.