You’ve probably seen the words LOW GI slapped on the odd cereal box or muesli bar. You may even know that GI stands for glycaemic index, and it has something to do with carbs…
But if that’s as far as your knowledge goes and you’re wondering what GI actually is, or perhaps more importantly, if you should be paying attention to it, you’ve come to the right place. Presenting your GI 101 guide!
Breaking down glycaemia
All the stuff we eat and drink provides energy to the body in different forms: primarily as carbohydrates, fats or proteins. Carbs are the body’s go-to energy source, because they’re the easiest to break down into simple sugars, like glucose. These simple sugars are carried to each cell through the bloodstream, allowing them to go about their business of keeping you alive.
The presence of glucose in your bloodstream is called glycaemia. You’ve probably heard it called by its more common term: blood sugar levels. These levels naturally increase and decrease as you eat and drink different things, and in a healthy body they’re regulated by a hormone called insulin, produced in the pancreas.
The glycaemic index
The glycemic index (GI) is a value out of 100 assigned to carbohydrate-containing foods, based on how quickly or slowly they cause increases in your blood sugar levels.
Foods low on the GI scale (think grainy bread, oats, yogurt and lentils) tend to release glucose slowly and steadily, so they have less effect on blood sugar levels. Foods high on the GI scale (think white bread, white rice, processed cereals and soft drinks) release glucose much faster and can cause spikes in your blood sugar levels.
Should I pay attention to GI?
What does this actually mean for you and your health? First off, there is room for moderate to high GI foods in a healthy diet. But everybody (and every body)’s needs will slightly different based on their individual situation.
Foods lower on the GI scale may help you feel fuller for longer by providing a slower, more gradual supply of energy from one meal to the next. Low-GI foods may also foster weight loss and help to reduce insulin levels and insulin resistance, as well keep blood sugar levels more stable in people living with diabetes (where the body can’t produce enough insulin to effectively regulate blood sugar levels.
Foods higher on the GI scale are a boon for energy recovery after exercise. They can also offset hypoglycaemia – that is, insufficient blood sugar levels and often related to the treatment of diabetes – by proving a quick burst of energy.
So, a marathon runner would probably need to include more high GI foods in his or her diet, while someone with diabetes would need to concentrate their efforts on low GI foods.
One piece of the puzzle
While the GI scale can be a useful guide in planning a diet and controlling blood sugar levels, it should be taken as one part of a larger puzzle. Considering the nutritional quality of your diet (that is, focussing on whole, unprocessed foods with lots of veggies), as well as your portion sizes, are just as important.
But if you’re keen to incorporate more low GI into your diet, watch out for our next post where we reveal some surprising choices (hint, one of them may be monk fruit!).