Akerhaug has authored the investigative journalism books "Norsk jihad" (Norwegian jihad; 2013) about Norwegian Islamists, and "En norsk terrorist" (A Norwegian terrorist; 2015) about Hassan Abdi Dhuhulow, the Norwegian perpetrator of the 2013 Westgate shopping mall attack in Kenya. Both books received good reviews in "Dagbladet". He was granted 100.000 from Fritt Ord for development of the book "Siste jul i Kairo" (Last Christmas in Cairo; 2016), about the persecution of Christians in the Middle East. Akerhaug is considered one of Norway's foremost experts on Islamic extremism, and is often referred to for commentary in Norwegian media.