Eating Vegetables First Regardless of Eating Speed Has a Significant Reducing Effect on Postprandial Blood Glucose and Insulin in Young Healthy Women: Randomized Controlled Cross-Over Study.
Level 2 - randomized trial
Randomized crossover trial in humans
PubMed 36904173 · doi:10.3390/nu15051174
What was done
In a randomized within-subject crossover study, 18 young healthy women consumed an identical 671 kcal test meal (tomato, broccoli, fried fish, boiled white rice) under three conditions on separate days: eating vegetables first at a fast pace (10 min), vegetables first at a slow pace (20 min), and carbohydrate first at a slow pace (20 min). Researchers measured postprandial blood glucose, insulin, triglycerides, and free fatty acids, alongside metrics of glycemic variability.
What was found
The abstract reports statistical significance without providing exact numerical values or effect sizes. Both fast and slow eating with vegetables first significantly reduced postprandial blood glucose and insulin concentrations at 30 and 60 minutes, as well as glycemic standard deviation, amplitude of excursion, and incremental area under the curve compared to slow eating with carbohydrates first. There was no significant difference between fast and slow eating when vegetables were consumed first, except that blood glucose at 30 minutes was significantly lower in the slow-eating vegetable-first condition compared to the fast-eating vegetable-first condition.
Why it matters
These findings indicate that consuming vegetables before carbohydrates blunts acute postprandial glycemic and insulinemic surges, suggesting that food sequence may moderate glucose spikes independently of eating speed.
Limits
The sample was very small (n=18) and limited entirely to young, healthy women. The design lacked a fast-eating carbohydrate-first control arm, exact quantitative values and lipid results (triglycerides, free fatty acids) were omitted from the abstract, and long-term metabolic outcomes were not assessed.
Cited by
- supports Eating vegetables at the beginning of a meal creates a fiber mesh in the intestine that slows glucose absorption and reduces postprandial glucose spikes.