Effects of community-based health education in food glycemic index on dietary modification of patients with type 2 diabetes mellitus

Abstract

Objective To evaluate the effects of dietary intervention with low glycemic index (LGI) and low glycemic load (LGL) on dietary knowledge and dietary modification of patients with type 2 diabetes mellitus (T2DM). Methods This study was a cluster randomized controlled study. From June to September 2010, 105 T2DM patients were randomly sampled from 3 residential areas (n=35 in each) in Jin Pen Ling community, Changsha, Hunan province and divided into three groups with a random number table: whole-day dietary intervention group (group A, n=35), breakfast dietary intervention group (group B, n=35), and control group (group C, n=35). Interventions included 3-month health education and dietary intervention. Dietary knowledge, dietary oils, glycemic index (GI), and glycemic load (GL) of the three groups were compared before and after intervention. Results Before intervention, all the three groups showed a low level of knowledge about GI (57.7%), and high levels of average GI value of each meal (69.71±8.55), GL value per day (132.45±16.25), and daily cooking oil intake [(39.95±20.64)g]. The average knowledge level about GI increased after intervention in both group A (96.3% vs. 57.1%, P 0.05). The reduction of daily cooking oil intake in group A was larger than those in group B and group C [(7.81±3.91)g vs. (-5.12±1.37)g, (7.81±3.91)g vs. (-3.45±5.95)g, both P<0.05]; so was the average GI value of each meal [group A, (5.95±2.27); group B (-0.85±1.87); group C, (-2.87±1.93); all P<0.05]. The changes of GL values in group A (11.31±4.31) was better than in group B (1.23±27.82) and group C (-0.43±18.40) (both P<0.05). Conclusions The average GI value, GL value, and daily cooking oil intake of T2DM patients were all at a high level before intervention, while the level of knowledge about GI was at a low level. Health education providing GI knowledge may effectively improve the knowledge about GI in T2DM patients, while LGI and LGL dietary intervention may promote diet modification. Whole-day dietary intervention may be more effective than breakfast intervention. Key words: Type 2 diabetes mellitus; Glycemic index; Glycemic load; Dietary modification