Tuesday, Aug 22, 2017
Abu Dhabi: How do the most popular and staple food items in the Emirati cuisine impact on blood sugar levels? This was the question to which a team of researchers from UAE University sought answers and their research has led to significant body of information.
The in-depth research project looked into 18 commonly consumed Emirati dishes, analysing their effects on a person’s blood sugar levels. The outcome is a much-needed dietary data which had previously not been available.
Led by UAE University (UAEU), the study assessed both the glycaemic index (GI) and glycaemic load (GL) of 18 foods such as biryani, harees (beef), and machbous (fish). As part of their research, 15 participants were brought in to consume the tested foods, with the participants’ sugar blood levels monitored afterwards. Other separate laboratory tests were also carried out on the foods to determine their GI.
A food with a high GI raises blood sugar more than a food with a medium to low GI. But the glycemic index does not take into account the amount of carbohydrate in a food. So glycemic load is a better indicator of how a carbohydrate food will affect blood sugar.
“This project began in 2010 because there was very limited information on Emirati cuisines. In western countries such as the United Kingdom and the United States, they have databases for all types of food they consume with important nutritional information, and so we wanted to have a similar type of electronic database for Emirati foods,” said Dr Ayesha Al Daheri, chairperson of the nutrition and health department at UAEU, who led the project.
The study had strict parameters for the participants.
“Conducting this research and gathering the data with the human participants was not easy, because they basically had to fast and consume no other foods before they came in. After that we gave them a portion of the foods we were studying, and then analysed their blood levels a few hours later,” said Dr Al Daheri.
The protein, fat, carbohydrate content of each food and its calorific value was evaluated at the university’s laboratory, she added.
“We purchased the foods from reliable restaurants who were known to cook traditional Emirati dishes. Purchases were made three times during one month - the beginning, the middle, and the end. This was done to make sure that the recipe did not change. The testing was done repeatedly,” she said.
The research revealed that the GI levels varied between the different foods, and that higher GI levels were down to factors such as how the food cooked, and what other ingredients were added to the dish.
In the low GI category were seven foods. “Chebab bread, khameer bread, harees, biryani, luqaimat, khanfaroosh, and habba hamra.”
“Six foods were classified as medium GI, these included Arabic bread, chami, machbous, khabisa, batheetha, and balalet,” said Al Daheri. And five foods had high GI values — regag bread, muhalla bread, fendal, thareed [beef], and arseyah.
Talking about how the GI value can be affected, she said, “Several factors can affect the GI value of the food and increase it, one of them is the type of oven used for baking the bread, or the temperature of the oven and the amount of yeast used. Other factors for increasing the GI could be the amount of sugar added and the high amount of white flour for foods like khabisa and balalet, while batheetha GI is mainly related to its content of date paste, ghee and sugar,” she explained.
“The thin surface of the bread for regag and muhalla with no addition of yeast makes the carbohydrate or starch availability high for digestion which can explain their high GI content. For fendal, it’s all about the type of potato used plus the added amount of sugar from date paste. For arseyah, it’s due to long hours of cooking that increase the digestibility of the rice. The high GI level for thareed is due to the use of regag bread which is also high a GI food,” she added.
Al Daheri also emphasised that while a food could have a low GI, that it’s overall GL could be high when portion sizes were taken into account. For example, khameer bread is classified as having a low GI value, but depending on the portion size a person consumes, that value can significantly increase.
“The GL considers the portion size of the food as well as the GI value of each food, which is considered in the calculation of the GL value of each food. In this regard, it is always recommended to take into consideration the portion size when calculating this,” she said.
Another factor to also take in is the fat content according to Al Daheri, as some foods are low in GI value, but not necessarily a healthy option due to their fat content.
“A specific food can be of a low GI value but at the same time it can contain high amount of fat. In this regard we should not only depend on the GI value as the sole indicator for a food but we should look into the whole nutrient value of the food,” she said.
Going forward, Al Daheri said that the plan was to share the project’s results with nutritionists and dieticians, and to produce educational materials for the general public.
“We are in the process of developing an Emirati exchange list for professionals like nutritionists and dietitians to utilise when they council their patients.
“We are also planning to produce flyers with information for the general population that contain information about Emirati foods and suggestions on how to consume them in a healthier way,” she added.
“Our findings can also be beneficial for policy makers, they can plan appropriate healthy diet programmes for the population and raise awareness,” she said.
GI vs GL: What’s the difference?
The glycemic index (GI) is a measure of how quickly a food can raise the level of blood sugar upon consumption. Carbohydrate-containing foods can be classified as high- (≥70), moderate- (56-69), or low-GI (≤55) relative to pure glucose (GI=100).
Glycemic Load (GL) accounts for both the quality and quantity of carbohydrates in a food, by including the serving size in its formula, as well as the food’s glycemic index.
Consumption of high-GI foods causes a sharp increase in blood glucose concentration that declines rapidly, whereas consumption of low-GI foods results in a lower blood glucose concentration that declines gradually.
GI values for foods (low to high)
Food itemGI value
By Sami Zaatari Staff Reporter
Gulf News 2017. All rights reserved.