... and it's no accident that berries* are favored by low carb dieters for their low sugar content: blackberries have about 5g of sugar per 100g, rapsberries 4.4g, bananas 12g.
*meaning small, tasty, slightly tart, colorful fruits that grow on bushes and tend to be fairly wild, not the botanical definition
You're looking at cultivated blueberries. Wild blueberries have between 5g and 7g sugar per 100g. They're typically smaller than their cultivated cousin. Their flavor is more intense, but their texture is slightly grittier.
Are those cultivated genetically different than wild varieties? Because as far as I can tell, sugar content is wildly affected by photosynthesis, which varies wildly by farm vs wild conditions. I have even more strong doubts that artificial selection is the cause of this.
*meaning small, tasty, slightly tart, colorful fruits that grow on bushes and tend to be fairly wild, not the botanical definition