Protein and veg before carbs helps keep blood sugar in check, say researchers

The order in which we eat food could play a vital role in how our bodies manage post-meal blood sugar and insulin levels, a small study has reported.

The data, published in Diabetes Care, tested the effect of food order using a typical Western meal - incorporating vegetables, protein, and carbohydrate - on post-meal (postprandial) blood sugar and insulin in overweight and obese people with type 2 diabetes.

The team, led by Dr Louis Aronne from at Weill Cornell Medical College, found that eating protein and vegetables before carbohydrates was linked to lower blood sugar and insulin levels after the meal – adding that the findings might impact the way clinicians advise diabetic patients and other high-risk individuals to eat, focusing not only on how much, but also on when carbohydrates are consumed.

“We’re always looking for ways to help people with diabetes lower their blood sugar,” said Aronne. “We rely on medicine, but diet is an important part of this process, too. Unfortunately, we’ve found that it’s difficult to get people to change their eating habits.”

“Carbohydrates raise blood sugar, but if you tell someone not to eat them – or to drastically cut back – it’s hard for them to comply,” he added. “This study points to an easier way that patients might lower their blood sugar and insulin levels.”

Research details

The team looked to validate and advance previous research that suggested eating vegetables or protein before carbohydrates leads to lower post-meal glucose levels. In the new study, the investigators looked at a whole, typically Western meal, with a good mix of vegetables, protein, carbohydrates and fat.

They worked with 11 patients, all of whom were obese and had type 2 diabetes and take an oral drug called metformin that helps control glucose levels.

To see how food order affected post-meal glucose levels, they had the patients eat a meal, consisting of carbohydrates (ciabatta bread and orange juice), protein, vegetables and fat (chicken breast, lettuce and tomato salad with low-fat dressing and steamed broccoli with butter) twice, on separate days a week apart.

On the day of their first meal, researchers collected a fasting glucose level in the morning, 12 hours after the patients last ate. They were then instructed to eat their carbohydrates first, followed 15 minutes later by the protein, vegetables and fat. After they finished eating, researchers checked their post-meal glucose levels via blood test at 30, 60 and 120-minute intervals.

A week later, researchers again checked patients’ fasting glucose levels, and then had them eat the same meal, but with the food order reversed: protein, vegetables and fat first, followed 15 minutes later by the carbohydrates. Post-meal glucose levels were then collected 

The results showed that glucose levels were much lower at the 30-, 60- and 120-minute checks – by about 29%, 37% and 17%, respectively – when vegetables and protein were eaten before the carbohydrates.

Insulin was also significantly lower when protein and vegetables were eaten first, said Aronne and his team.

“Based on this finding, instead of saying ‘don’t eat that’ to their patients, clinicians might instead say, ‘eat this before that,’” said the lead researcher.

“While we need to do some follow-up work, based on this finding, patients with type 2 might be able to make a simple change to lower their blood sugar throughout the day, decrease how much insulin they need to take, and potentially have a long-lasting, positive impact on their health." 

Source: Diabetes Care

Volume 38, Number 7, e98-e99, doi: 10.2337/dc15-0429

“Food Order Has a Significant Impact on Postprandial Glucose and Insulin Levels”

Authors: Alpana P. Shukla, et al