What you need to know about GL

how blood glucose functions within the body

Have you heard about GL or GI but aren't really sure what it means or whether it's something you should be paying attention to? This article takes a closer look at this useful tool and gives some pointers for using it in your own healthcare.

GL stands for Glycaemic Load. It takes into account how much carbohydrates are in a given food and also what quality those carbohydrates are and combines them into a single figure. GI stands for Glycaemic Index and measures the effect a particular carbohydrate food has on blood sugar levels as compared to the effect of the same amount of pure sugar on blood sugar levels. The main problem with GI is that it does not provide an accurate picture of the entire blood sugar raising potential of particular foods. Instead it only provides an idea of how rapidly a carbohydrate turns into sugar rather than how much of that carbohydrate is in the food serving. For this reason, GL is becoming more often referred to in the food industry as it takes into account the quantity of carbohydrates as well and is a measure of how a specific serving will impact blood sugar levels.

Glycaemic Load and Blood Sugar

Understanding the GL of a food is a key tool for balancing your blood sugar, which in turn is one of the main components of good health. Foods that have a high GL rating will result in the body storing more fat, whereas a lower rating will result more in fat burning.

The science behind this is very simple. Your body is designed to burn glucose to access energy. Carbohydrates, such as grains (bread, pasta, rice) and fruits, break down into glucose within the body. Unfortunately, in many modern diets, we are consuming the wrong kinds of carbs, which result in an excess of blood glucose. Once available glucose has been used up for energy in the body, any excess glucose ultimately gets stored as fat. When glucose levels get too high too quickly, the insulin hormone comes to the rescue to get the glucose out of the blood stream. However, when glucose levels drop too low too quickly, this leaves the body without enough energy to meet its requirements, which then manifests as hunger and cravings as the body’s way of trying to get energy back into the body as quick as possible. Unfortunately when blood sugar levels and thus energy levels are low, the body then craves the very foods that convert to glucose the quickest in order to get energy ASAP. When your body loses control of blood sugar, weight gain is inevitable, but when blood glucose is balanced, you can maintain a steady stream of energy alongside a healthy, moderated appetite. When blood sugar is too high, you put on weight more easily. When it is too low, you will feel exhausted and lethargic.

a diagram showing how blood sugar levels affect weight gain, mood and concentration by london nutritional therapist tracy tredoux

Keeping blood sugar levels stable depends on choosing foods that have a low GL. These are not always the foods that you would expect (for example, cornflakes are very high GL, whereas peanuts are relatively low), so it is advisable to keep a list or an app handy that will help you to find out which foods are better for balancing blood glucose levels.

The Diabetes Connection

Diabetes is a condition in which glucose (sugar) levels in the blood are higher than normal. There are two kinds of diabetes (type 1 and 2). Both types involve insulin, a hormone responsible for controlling the level of glucose in the blood. Type 1 diabetic patients do not produce enough insulin and therefore need to inject it, whereas type 2 diabetic patients, produce insulin, but the cells become insensitive to it and so it is unable to do its job. Type 2 diabetes accounts for over 90% of all diabetics and is often a result of preventable diet and lifestyle factors.

When we eat high GL foods, such as sweets, biscuits, pasta, rice, bread, carbonated drinks and fruit, they break down into glucose. That glucose is then absorbed into the blood. When glucose levels become raised, we produce insulin, which delivers glucose to the body’s cells for energy and then stores any excess as fat. Eating a diet of predominantly high GL foods puts a constant stress on the body to keep on producing insulin. Eventually, the cells develop an immunity to the insulin and stop absorbing glucose efficiently, leaving you with low energy and excess blood glucose. If insulin resistance is not controlled, it can lead to type 2 diabetes and even heart disease.

Should I follow a low GL diet?

A low GL diet can be a good option for anyone with type-2 diabetes, or anyone who is at risk of developing the condition. As a rule of thumb, anyone whose BMI is +30 is eighty times more at risk. Low GL is also a safe and healthy way to lose weight without ever starving yourself or missing out on any nutrition. Please remember to consult with your doctor or qualified nutritional therapist before embarking on any new eating programme to find out if it is suitable for you and your unique disposition.

In general, people who follow a low GL diet report feeling more energised and alert, along with experiencing less hunger and cravings. Instead of counting calories, you count the GL, which is often very different to the calorific content of food. Supporting this is the finding that our calorific intake has not increased in the last 50 years, while our obesity levels have rocketed.