blood sugar levels

Carbohydrate based meals can significantly raise blood sugar levels within the first two hours of consuming the meal but researchers have now shown that the order in which you eat the carbohydrate part of the meal can help to reduce the initial rise in sugar levels.

The study was carried out by researchers from the Comprehensive Weight Control Center at Weill Cornell Medical College. 11 participants with metformin-treated type 2 diabetes took part in the study.

The study tested two meals which were exactly the same and eaten 1 week apart. Outside of the two meals being tested, participants were able to eat their normal diet. A 12 hour fast had to be taken before the meals on the test days however. Blood glucose tests were taken before the meal and at 30, 60 and 120 minute intervals after the meal was started.

The meal on the first test day was eaten in the following order:

  • Ciabatta bread and organge juice (carbohydrate foods)
  • Skinless grilled chicken breast, lettuce and tomato salad, and broccoli

When the meal was re-tested a week later, it was eaten in reverse order with first the chicken breast and vegetables followed by the ciabatta and orange juice. To reduce bias, the two parts of the meal (carbohydrate and non-carbohydrate foods) were started 15 minutes apart.

Lower glucose and insulin levels

When the carbohydrates were eaten first, blood glucose reached a peak level an hour after starting the meal. At the 60 minutes mark blood glucose levels reached an average of 199 mg/dl.

When the carbohydrates were second, the rise in blood glucose levels was significantly delayed. The highest of the readings was taken at the 120 minute mark, with an average blood glucose level of 141 mg/dl recorded.

The results also showed that insulin levels were significantly lower when carbohydrates were eaten after the chicken and vegetables. This is notable as having lower circulating insulin should lower the risk of weight gain and lower the further development of insulin resistance.

One problem with the way the study was run is that glucose measurements were only taken for up to 2 hours after the meal. As a result, the study cannot guarantee that blood glucose and insulin levels did not reach a higher level after 2 hours when the carbohydrate was eaten last.

However, the study shows that having the carbohydrate element first helps reduce blood glucose levels in the first 2 hours after the meal and this suggests that it could help people feel fuller for longer as well.

The study is published in the Diabetes Care journal for July.