Publication:

不同升糖指數的飲食與運動對脂肪代謝的影響

以升糖指數(glycemic index, GI) 來分類食物中碳水化合物的來源已被廣泛的運用。再過去十年來的流行病學的研究顯示，攝取高GI 碳水化合物的飲食，與心血管疾病，糖尿病，肥胖症，以及一些癌症有密切的關係。上述的這些慢性疾病，與脂肪代謝異常有高度的相關。這有可能是因為攝取高GI 的碳水化合物，導致分泌大量的胰島素，進而促進脂肪的貯存，然而這些流行病學的研究缺乏臨床的實驗來證實。另外，在一些研究指出，低脂高碳水化合物的飲食配合步行運動(brisk walking)，能有較佳的脂肪耐性測驗表現，但是這些飲食的設計，並未考慮其碳水化合物來源的生理效應。本研究探討不同GI 碳水化合物的飲食與運動對於脂肪代謝的影響。六名受測者接受兩次連續三天分別隨機的給予高或低GI 的飲食，飲食控制期結束後第四天實施口服脂肪耐性測驗 (oral fat tolerance test)。另外兩次給予受測者相同的飲食控制，並且在飲食控制期，以50%VO2max 走路運動一小時。結果顯示運動能夠有效的降低餐後血液中的三酸甘油脂濃度，但是在低GI或者高GI之間並沒有顯著差異。而低GI的飲食加上運動能有較佳的胰島素敏感度。

The effect of different glycemic index diet and exercise on fat metabolism Glycemic index (GI) as a classification of carbohydrate has been wildly received notice. In the past ten years, many epidemiological studies have been shown strong connection between high GI carbohydrate diet and cardiovascular diseases, diabetes, obesity, and cancers. The above chronic diseases and symptoms are highly related to abnormal fat metabolism, especially on obesity objects. This may be due to high GI carbohydrate induces massive insulin secretion to facilitate fat storage. However, these epidemiological studies are in short of clinical or experimental trials on the effect of GI diet on the fat metabolism. In addition, several studies have been shown the positive effects of low fat diet and exercise on fat tolerance performance. However, these studies did not consider the nature of carbohydrate source. Six healthy male subjects with normal weight was recruited in each study. Subjects consumed either high or low GI diet without exercise (HGI, LGI) or with exercise (HGI+EX, LGI+EX) at 50%VO2max for three days in a randomized order before undertaking the fat tolerance test (OFTT). The results showed that exercise trials were effectively attenuated postprandial lipemia. Glycemic index carbohydrate effect were no observed. However, LGI+EX may improve insulin sensitivity.