A spoonful of sugar - Food for the Brain

A spoonful of sugar

To become a master of your blood sugar control and sugar cravings, you must take both quality and quantity of carbs into account when planning your diet. Our advice is to eat fewer carbs overall and the right kinds.

Together this is called the Glycemic Load, GL for short, of a food, as shown in the table below. It takes into account both how many actual grams of carbs you eat, but also how quickly the kind of sugar in the carbs is released. The speed of release of sugar in the food you eat is called Glycemic Index, or GI for short, which is shown in the table below. Pure glucose, which is what ends up in your blood after digesting carbs, has a GI score of 100 by definition.

Dr David Unwin, a GP from the UK, has a terrific way to illustrate GL for his diabetic and overweight patients. Instead of trying to explain the concept, he simply shows them the ‘teaspoons of sugar equivalent’ for each food, as indicated in the table below.

Food GI Serving size GL Teaspoons of sugar
Coco Pops 77 30g 20 7.3
Cornflakes 93 30g 22 8.4
Mini Wheats 59 30g 13 4.4
Shredded Wheat 67 30g 14 4.8
Special K 54 30g 12 4.0
Bran Flakes 74 30g 13 4.8
Porridge 63 150ml 6 2.2
White 71 30g 10 3.7
Brown 74 30g 9 3.3
Rye (69% wholegrain rye flour) 78 30g 11 4.0
Wholegrain barley (50% barley) 85 30g 15 5.5
Wholemeal (stoneground flour) 59 30g 7 2.6
Pitta (wholemeal) 56 30g 8 2.9
Rough oatcake 35 10.4g 2 0.7
Banana 62 120g 16 5.9
Grapes (black) 59 120g 11 4.0
Apple (Golden Delicious) 39 120g 6 2.2

Adapted, with permission, from David Unwin’s charts in the Journal of Insulin Resistance (2016)

The GI column relates to how quickly or slowly each of these foods releases its sugar. For instance, the GI for strawberries is a relatively low 40 per cent (compared to 100 per cent for glucose). In addition, they have an extremely low glycemic load (just 1 GL), which means that a typical (quite large) 120g portion provides the equivalent of only 0.4g of white sugar. By contrast, while an apple’s GI is slightly lower, at 39 per cent, it contains more actual carbs so it has a much higher glycemic load (6 GL) and therefore it raises blood sugar levels six times as much as the same quantity of strawberries.

The last column converts the GL score into the equivalent number of teaspoons of (white) sugar. So, for example, a 120g apple would have the same blood sugar effect as 2.2 teaspoons of sugar. A banana, one of the highest sugar fruits, has the equivalent of 5.9 teaspoons of sugar.

Two oatcakes with a protein-based dip such as hummus or taramasalata (fish roe paste), high in omega 3 DHA, is only 4 GLs, or 1.5 teaspoons of sugar equivalent. Aim for 5 GLs for a snack.