Abstract

The glycemic index and glycemic load of water yam (Dioscora alata Linn) were studied in 75 volunteer subjects using standard methods in order to determine the effects of processing on the glycemic index and glycemic load of water yam. The subjects who were of both sexes and within the age bracket of 20-30 years with BMI ranging from 23.99-24.49 kg/m² were randomly selected from Akanu Ibiam Federal Polytechnic, Unwana, Afikpo, Ebonyi State, Nigeria. The subjects were divided into three groups designated A, B and C. Group A (control group with 15 subjects) were fed with glucose (50 g) dissolved in water while groups B and C (with 30 subjects/group) were fed with roasted and boiled yams that provided 50 g of carbohydrate respectively for 5 days. Blood glucose levels were determined in the subjects prior to eating and at intervals of 0, 60, 120, 180, 240 min, respectively after eating. The results of the proximate analysis revealed the presence of the following; moisture (80.46±42.10 and 77.98±43.85), ash (3.28±0.33 and 3.90±0.78), crude fibre (2.30±0.21 and 2.20±0.14), crude lipid (7.00±0.21 and 0.66±0.18), crude protein(5.41±0.99 and 5.18±0.83) and carbohydrate (59.10±1.48 and 59.10±1.48) for boiled and roasted water yams respectively. The results of the glycemic index and glycemic load analysis showed a statistical significant increase (p<0.05) in the blood glucose level of the subjects fed with roasted water yam than the subjects fed with boiled water yam indicating that boiled water yam has lower glycemic index and glycemic load and hence could be useful in the treatment and management of diabetes mellitus and its complications.

Keywords:

Blood, determined, experimental, glucose, levels, subjects,

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