Glycaemic Response to some Commonly Eaten Fruits in Type 2 Diabetes Mellitus

BACKGROUND: It is not known which of the commonly consumed fruits in Nigeria are suitable for persons with diabetes mellitus especially with regards to the attendant plasma glucose response (PGR) to consumption of such fruits. OBJECTIVES: To determine and compare the PGR to commonly eaten fruits in patients with diabetes mellitus. METHODS: Ten persons with type 2 diabetes mellitus were studied. Fifty gram portions of five fruits containing 50g carbohydrate [ banana, Musa paradisiaca; orange, Citrus sinensis; pineapple, Ananus comosus; mango, Magnifera indica; pawpaw, Carica papaya], and glucose were randomly fed to the study subjects at one-week intervals. Blood samples were collected in the fasting state and half hourly over a 2- hour period post-ingestion of the fruits or glucose for plasma glucose determination. Plasma Glucose Responses were assessed by the peak plasma glucose concentration (PPPG), maximum increase in postprandial plasma glucose (MIPG), two-hour postprandial plasma glucose level (2hPG) and incremental area under the glucose curve (IAUGC). RESULTS: The mean ± s.e.m. PPPG in mmol/L were: banana, 9.0± 1.6. orange, 8.1± 0.8; pineapple, 9.2±1.1; mango, 8.0 ± 1.1; and pawpaw, 7.8±0.9. The mean ± sem IAUGC in mmol.min/ L were: banana, 131.7±53.4; orange, 108.7±29.8; pineapple, 115.3±33.2; mango, 101.6 ± 28.7; and pawpaw, 124.1± 46.1. However, mango showed the least MIPG (1.8 ± 0.5 mmol/l) by followed by orange and pawpaw. The IAUGC also followed this pattern. There were no significant differences among the glycaemic indices of the fruits. Glucose load produced a significantly higher IAUGC than the fruits (orange, pineapple, mango, pawpaw, p<0.005; banana, p<0.025). CONCLUSION: The plasma glucose response to consumption of Nigeria fruits are similar. The PGR indices to all fruits were less than the PGR after an equivalent carbohydrate load of glucose. It appears safe to recommend these Nigerian fruits to persons with diabetes within the prescribed daily total calorie intake.