How many teaspoons of sugar in bran flakes?

Bran flakes are wheat flakes with added wheat bran, sold under several brand and supermarket names. They appear in three of Dr Unwin’s published sources, more than most foods in this dataset, and the sources do not describe them the same way.

The breakfast cereals chart gives a 30g bowl a glycaemic index of 74. Table 1 of the 2016 paper lists the same 30g portion with a GI of 50, 20g of available carbohydrate and a glycaemic load of 10. Both print the same teaspoon figure, 3.7. The third source, the chart titled “A healthy breakfast: cereals, toast, fruit juice?”, also uses 3.7, as the first item in a breakfast it totals with milk, toast and apple juice.

Table 1’s numbers are consistent with each other: 20g at GI 50, divided by 100, is a load of 10. The cereals chart prints no carbohydrate figure. With its higher GI, the same teaspoon figure would require a smaller amount of carbohydrate in the bowl, and the published material does not explain the difference. The teaspoon figure is used as printed, and the load on this page was back-calculated from it rather than from either GI.

The disagreement is listed with the others on the sources page.

Bran is the outer layer of the grain, and most of its fibre is insoluble. In a flaked cereal it is combined with wheat flour, sugar and malt, and the proportion of bran differs between brands, so the name on the box does not fix the recipe.