'Eat carbohydrates last' advice for diabetics
“Eating protein and veg BEFORE carbs…could help diabetics control their blood sugar,” the Mail Online reports. However, the advice is based on a very small study and the influence of food ordering really needs to be checked in much larger studies before it can be made an official guideline.
The study involved just 11 people, most of whom had obesity-related type 2 diabetes, who ate the same meal one week apart.
On the first occasion, they ate the carbohydrates 15 minutes before the protein and veg; on the second occasion, they reversed the order.
Post-meal blood glucose was significantly lower when the carbohydrates went last compared with first.
The study lends support to previous research that carbs have the biggest effect on blood glucose. However, the study has many limitations, which require larger and longer-term studies to resolve.
For example, it is not known what the effects would be of sustaining this eating pattern in the longer term.
Though it is unlikely to cause you any harm to consider altering the order you eat food items to put carbohydrates last, the most important thing for people with and without diabetes is to follow a healthy, balanced diet.
If you do have diabetes, never make any drastic changes to your diet without first consulting with the clinician in charge of your care.
Where did the story come from?
The study was carried out by researchers from Weill Cornell Medical College, New York, and was funded by the Clinical and Translational Science Center at Weill Cornell Medical College, and the Dr. Robert C. and Veronica Atkins Curriculum in Metabolic Disease at Weill Cornell Medical College Grant.
The study was published in the peer-reviewed medical journal Diabetes Care, on an open-access basis, so the research is free to read online or download as a PDF.
The Mail’s coverage has not considered the various important limitations of this small pilot study. For one, its headline “The order you eat your food affects your health” is incorrect. Though it may be inferred that a sustained effect on blood glucose control could help people with type 2 diabetes, this study hasn’t looked at longer-term health effects or measured any health outcomes at all.
What kind of research was this?
This was a small crossover study designed to investigate the effect the order of food consumption has on blood glucose level after eating on people with type 2 diabetes.
The researchers explain how post-meal glucose is a good indicator of blood glucose control and the risk that a person has of diabetes complications. There is said to be existing evidence that carbohydrate is the food type that has the biggest effect on blood glucose. Some studies have shown that eating whey protein before a meal reduces post-meal levels, but there is said to be little information on the effect of food order on people with type 2 diabetes. This is what this pilot study aimed to look at.
What did the research involve?
This study involved 11 adults (six female, five male) with treated type 2 diabetes, who were involved in an existing study of the effects of food order on post-meal glucose when eating a typical Western diet including vegetables, proteins and carbohydrates. The participants had an average age of 54 years and were obese (their average body mass index was 32.9).
Participants attended the study centre for two test occasions, one week apart. On each occasion, they were fasted for 12 hours overnight before eating the same 628-calorie meal made up of 55g protein, 68g carbohydrate and 16g fat.
On the first visit, they ate carbohydrates (ciabatta bread and orange juice), followed 15 minutes later by protein (skinless grilled chicken breast) and vegetables (lettuce and tomato salad, with low-fat Italian vinaigrette and steamed broccoli with butter). On the second visit, the food order was reversed so that the carbohydrates went last. On both occasions, blood glucose was measured before the meal and 30 minutes, one hour and then two hours after.
What were the basic results?
When vegetables and protein went first, average post-meal blood glucose was significantly reduced at all time points compared to when carbohydrate went first. Blood glucose was 28.6% lower at 30 minutes, 36.7% lower at one hour and 16.8% lower at two hours after the meal.
Insulin levels were also lower at one and two hours, suggesting that the body did not need to produce so much insulin to control blood sugar.
How did the researchers interpret the results?
The researchers conclude from their pilot study that “the temporal sequence of carbohydrate ingestion during a meal has a significant impact on [post-meal] glucose and insulin”.
In short, they thought the order you eat carbohydrates during a meal affects your glucose and insulin levels afterwards.
Conclusion
This pilot study seems to support the findings of previous research that eating carbohydrates has a significant effect on post-meal blood glucose. Eating carbohydrates first, before protein and vegetable portions, raised glucose levels more than eating carbs at the end of the meal. This study specifically tested obese people with type 2 diabetes and showed that the effects seem to hold true.
While the research suggests that ordering the meal could control blood sugar levels, particularly in people with type 2 diabetes, there are several important points to bear in mind.
Size of study
This was a very small study involving only 11 people with type 2 diabetes. The results from this small group may not be identical to those that would have been obtained from other or much larger samples of people.
Short-term follow-up
The effects have only been measured in the immediate term, up to two hours after a single meal. It is not known whether there would be a meaningful difference in blood glucose control if this carbs-last pattern of eating were continued in the longer term at each meal.
The study doesn’t show whether altering food order could improve blood glucose control long term in type 2 diabetes, thereby reducing the risk of disease complications.
Neither does the study inform whether altering food order could help people with or without diabetes to lose weight and reduce the risk of being overweight or obese.
Uncertainty on timing
They tested eating only one specific meal first thing in the morning. It is completely unknown from this study how effects may differ, depending on factors such as the time of day food was eaten, if it was of a different composition of foods rather than this specific meal, or if it was of different calorie content.
Practicality
On a practical level, this study involved eating the carbs 15 minutes from the protein and vegetable components. This isn’t always going to be practical in normal daily life, when the different components are often combined and eaten at the same time. It is not known from this whether you need the 15-minute time delay. For example, if you were eating food on a plate that had rice or potatoes, whether you could obtain the same effect on blood glucose if you ate the carbs last, but immediately after eating the other food stuff.
Overall, longer-term studies will be needed to see if reversing food order could have sustained meaningful effects on blood glucose control in type 2 diabetes.
Though it is unlikely to cause you any harm to consider altering the order you eat food items, the most important thing for people with and without diabetes is to follow a healthy, balanced diet.
Read more about healthy living with diabetes.
