Onion and green beans in diabetic patients
What it found
In people with diabetes, green beans lowered blood sugar and blood fats, and onion lowered blood sugar, over one-week diet periods.
The authors say the lipid changes were too small to matter in practice.
What they found
Studies in people
Green beans and blood sugar
In 20 poorly controlled diabetic patients, the green bean diet lowered average blood sugar by 33.08 mg%, which was statistically significant. The authors note the pre-study blood sugar levels were high.
Green beans and blood fats
The green bean diet also lowered serum cholesterol by 8.10 mg% and triglyceride by 6.83 mg%, both statistically significant. The authors say these lipid falls were too small to matter clinically.
Onion and blood sugar
In 20 well controlled diabetic patients, the onion diet lowered average blood sugar by 10.72 mg%, a statistically significant drop. The authors suggest the effect might be larger if starting blood sugar levels were high.
Onion and blood fats
No significant changes in cholesterol or triglyceride were found during the onion diet. The authors note the pre-study levels of these fats were already low, especially triglyceride.
B-diet and cholesterol
In 260 well controlled diabetic patients, the B-diet lowered cholesterol by 31.75 mg%, a statistically significant effect. It did not raise fasting triglyceride levels.
B-diet and blood sugar
The B-diet lowered fasting blood sugar by 2.82 mg% and 2-hour post-breakfast blood sugar by 4.01 mg%, both statistically significant. The authors say the fall was too small to be meaningful for patients.
What the authors conclude
- They conclude that green beans showed apparent hypoglycemic and hypolipidemic effects, though the lipid effects were too low to be clinically important.
- They state that onion lowered blood sugar but had no significant effect on blood fats in this study.
- They suggest that further study is needed to investigate the real clinical importance of green beans and onion in diabetes.
How it was done
The standard Western-style diabetic diet was poorly followed by patients in Indonesia, leading to uncontrolled diabetes. Onion and green beans are traditional medicines still widely used in Indonesian rural areas, and earlier work had suggested they affect blood sugar and blood fats.
Three separate randomised crossover studies were done in non-insulin dependent diabetic outpatients. Study I compared two diets in 260 well controlled patients; Study II gave 20 well controlled patients either the B-diet plus 3 x 20 g fresh onion a day or the B-diet alone; Study III gave 20 poorly controlled untreated patients either the B-diet plus 3 x 200 g green beans a day or the B-diet alone. Each diet period lasted one week, and the groups swapped over.
What it can’t tell you
- The diet periods lasted only one week, so the longer-term effects of onion and green beans are not known.
- The number of patients in the onion and green bean studies was small, so the results may not apply to all people with diabetes.
- The authors note that the pre-study blood fat levels were already low, which may have limited how much they could fall.
The paper
- Title
- Metabolic effects of onion and green beans on diabetic patients
- Type
- Randomised controlled trial
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Tjokroprawiro A, Pikir BS, Budhiarta AA, et al (1983). Metabolic effects of onion and green beans on diabetic patients. The Tohoku journal of experimental medicine. doi:10.1620/tjem.141.suppl_671Free full textPubMed 6393443DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error