Alasdair MacDonald, procurator fiscal for Dornoch, north east Scotland, said the decision had been taken in conjunction with the family of Verity Linn. The 49-year-old was found dead by a fisherman north of Cam Loch, near Elphin, in a remote area of Sutherland, in September.
Her body was near a tent and it is believed she had been fasting before her death.
Ms Linn is thought to have been a follower of Australian new-age guru Ellen Greve, known as Jasmuheen, who advocates "breatharianism" or "living on light".
A diary found among her belongings suggested she had been taking part in a spiritual cleansing programme.
She was also a member of the Findhorn Foundation in Morayshire, but members of the educational and spiritual establishment, founded in 1962, denied any involvement with Jasmuheen.
Mr MacDonald said: "The circumstances of Verity Linn's death were fully discussed with the next of kin and they were kept informed. "Obviously their views were taken into consideration and a decision was taken not to hold a public inquiry."