Table 3.

Human studies in support of anti-diabetic properties of noni.

Type of Noni Products, Dosage and Duration	Study Rationale	Subject Demographics	Study Outcomes [ref]
Type of noni product, dosage and duration unknown.	Population based observational study in Papua New Guinea.	365 participants from three provinces of Papua New Guinea Above 16 years of age.	Habitual intake of noni was protective against betel quid-associated T2D [89].
Juice from Morinda lucida leaves mixed with juice from Saccharum officinarum leaves and water administered twice daily for 12–16 weeks. Exact dosage of noni juice unknown.	Ethnobotanical survey to identify medicinal plants used to treat diabetes.	100 participants from five central districts of Lagos State in southwestern Nigeria consisting of traditional medical practitioners, herbalists and herb sellers (76% responders were males).	Morinda lucida was among the principal anti-diabetic plants to be used in traditional therapy to treat diabetes. Anti-diabetic outcomes were not specified [91].
One cup of Morinda citrifolia juice obtained from peeled and crushed fruits, three times a week.	Document ethnopharmacological data regarding the use of natural resources among diabetic population of Mauritius.	320 diabetic patients (42% males and 58% females) 20 traditional medicine practitioners (55% males and 45% females).	Morinda citrifolia was documented to be most widely used by both, diabetic individuals and traditional medicine practitioners to treat diabetes. Perceived to be beneficial in treating diabetic neuropathy, diabetic dyslipidemia, and hypertension [92].
Among 58 users of Morinda citrifolia L., 26 used leaves, 12 used stems, 4 used bark, 4 used roots and only 2 individual used fruits. Preparations consisted of decoction, juices or both. Exact dosage unknown.	Ethnopharmacological survey to identify correlation between use of traditional Palauan medicines and non-communicable diseases such as diabetes	520 individuals undertook the survey among which only 188 responses were conclusive. 61% responders were females and 18% were traditional healers.	Noni had no effect on lowering blood glucose, but effectively reduced weight among all 15 users and lowered high blood pressure among 42% of the users [93].