It is thought that all the Teda are Muslims. Their Islamization dates very probably to early in the Arab conquest, although most education in the Quran and in the intricacies of the legal system was a result of the establishment of Senusi schools in Libya and Chad within the last century. Although there are some traces of pre-Islamic belief, most of these have been incorporated into the Muslim system. The Islamic calendar is followed. Prayer is regularly practiced by both men and women, as is the Ramadan fast and zakat. Inheritance is Islamic. Although the Tibesti does not shelter many men educated in the Quran because few return to live permanently in the mountains, there are families boasting five generations of religiously learned men. In the late twentieth century more and more Teda, both men and women, have been able to perform the hajj.
The health status of the Teda as a group has generally been good. The principal problems are seasonal caloric deficiencies and periodic protein deficiency. In years when nutritional stress has been prolonged, susceptibility to respiratory infections has been a serious health problem. In the late twentieth century rheumatism, dental deterioration, and syphilis have become common.