If you have ever read fitness magazines or explored the web for nutritious recipes or healthy food items, you must have come across the word “Glycemic Index”. They say that you must consume food items having a low glycemic index, especially if you’re diabetic. But what does glycemic index mean? And why should you have a diet having low glycemic index foods?
Well, keep reading because we will be telling you everything you need to know about glycemic index.
So, what is glycemic index in the first place?
Glycemic index (GI) is a metric used to rank foods high in carbohydrates according to how they affect blood sugar levels. It was initially created to assist diabetics in controlling their blood sugar levels, but it has since been adopted by a large number of people as a nutritional tool for choosing foods that could have an impact on their overall health.
A low-glycemic diet may offer several health benefits. Selecting foods with a low glycemic index can help you reduce sharp spikes in your blood sugar. Conversely, consuming a food with a high glycemic index will also likely cause your blood sugar to rise more sharply. Additionally, choosing low glycemic foods may lower liver fat, and promote weight loss in the short term, among other health benefits.
What the scale denotes
Higher numbers on the glycemic index numerical scale, which goes from 0 to 100, indicate a quicker and more significant rise in blood sugar levels. The reference point is 100 for pure glucose’s GI.
How is the glycemic index calculated?
A portion of a particular food containing 50 grams of digestible carbohydrates is given to each subject, and the blood sugar response is monitored over a predetermined amount of time to determine the GI. Next, the response is contrasted with the blood sugar response resulting from 50 grams of pure glucose consumption.
Classification and what the number means
High GI foods (70 and above):
Carbohydrates that are broken down quickly by the body and cause substantial fluctuations in blood sugar have a high GI rating. It is generally recommended to consume high-GI foods in moderation, especially for those with diabetes. Some high GI foods are:
- Sugar and sugary foods
- Sugary soft drinks
- White bread
- Potatoes
- White rice
- Cornflakes
- Instant noodles
- Potatoes
Low (55 or less):and medium GI foods (56-69):
Low or medium GI foods are broken down more slowly and cause a gradual rise in blood sugar levels over time. Some examples are:
- Some fruit and vegetables
- Pulses
- Soy products
- Beans
- Orange juice
- Basmati rice
- Whole-grain foods, such as porridge oats
Factors influencing GI of foods:
Processing:
Generally, foods that have been ground, pounded, ground, mixed, mashed, and refined have higher GI values. Because of this, the GI of most processed foods is higher than that of the corresponding unprocessed food. For example, instant oatmeal may have a higher GI than steel-cut oats.
Fibre and fat content:
Oats and legumes are examples of foods high in soluble fibre that lower the GI because they take longer to empty from the stomach. Conversely, insoluble fibre, like that present in digestive bran, has minimal impact on the food’s ability to be absorbed and digested. Therefore, foods that contain bran do not always have a lower GI than foods that do not.
Sugar:
Foods with a very high GI may have their GI lowered by sugar because it competes with starch for the liquid needed for gelatinisation.
Cooking method:
The way a food is cooked can also influence its GI. For example, overcooking pasta may increase its GI.
Speed of eating:
Various studies have demonstrated that blood glucose levels rise less rapidly when eating more slowly.
Lifestyle factors:
A person’s glycaemic response to food can be influenced by a variety of lifestyle factors, many of which are challenging to control even in laboratory settings (e.g. prior exercise, stress, lack of sleep, composition of previous meal(s), etc.).
Closing thoughts
The glycemic index is a valuable tool for understanding how different carbohydrates affect blood sugar levels. However, it’s important to consider the overall context of a person’s diet and lifestyle, as well as individual variations in response, when making dietary choices based on the GI.
