Reading labels when you are watching blood sugar

Sugar appears in three separate places on a packet, and each one answers a different question. Reading the wrong one is the most common reason a label feels misleading when it is being perfectly honest.

The three places

Total sugars, on the nutrition panel. Every sugar in the product, whether it arrived in the fruit or was tipped in from a sack. This is the number most people read and it is the least specific of the three.

Added sugars, directly underneath. The US rule is precise about how this appears: the amount must be indented under total sugars and “prefaced with the word ‘Includes’ followed by the amount (in grams) ‘Added Sugars’”. So a yoghurt reading 12 g total and Includes 8 g Added Sugars is telling you 4 g came with the milk and 8 g came from a decision.

The ingredient list, where the sugars are named. This is where sugar becomes hard to find, because a great many of its names do not contain the word.

Why added sugars is the more useful line

Because the two numbers answer different questions and only one of them is about the manufacturer.

Total sugars in a plain milk, an unsweetened yoghurt or a piece of fruit is largely lactose or fructose that was always there. Total sugars in a flavoured version is that plus whatever was added. Comparing two products on total sugars alone will sometimes rank the plainer one worse.

For blood glucose, of course, your body does not care which line a gram came from. What the added sugars line gives you is a way to compare products and see what a recipe chose to do, which is a different and still useful thing.

The line that may not be there at all

Sugar alcohols. Sorbitol, maltitol, erythritol, xylitol, the ones ending in -ol that appear in almost everything sold as sugar-free.

The US rule makes this declaration voluntary. A manufacturer may state grams of sugar alcohol and may equally leave it out, so a product can be built on Sorbitol and the panel need not quantify it.

They also behave differently from each other. Some are absorbed slowly and raise glucose modestly, some barely at all, and several cause digestive trouble at ordinary portions. That variation, and a panel that may be silent on the amount, is why the ingredient list matters more here than anywhere else on the label.

The names that do not say sugar

This is the part the panel cannot help with, because the panel gives totals and the list gives identities.

High fructose corn syrup is the famous one, but it is famous partly because it is easy to spot. The harder ones are the plain-sounding entries.

Maltodextrin is not sweet and is not called a sugar. It is starch broken into short chains and it is digested quickly, with a glycaemic index that can run higher than table sugar. A product can be low in sugars, high in maltodextrin, and behave in a way the panel did not prepare you for.

Barley malt extract is a sweetener made from sprouted grain, and it reads like a flavouring.

Honey is sugar made by bees. It carries trace nutrients and a better reputation than it earns on this particular question, and it counts as an added sugar when a manufacturer puts it in.

Then the long tail: dextrose, maltose, fruit juice concentrate, agave syrup, rice syrup, molasses, treacle, invert sugar, and the various syrups. All of them are sugars and none of them says so. The index of names on this site exists for exactly this, and it is worth one look rather than memorising a list.

Sweeteners that are not sugars

Aspartame and Sucralose contribute effectively no carbohydrate, which is why they appear in products aimed at this reader.

They come with their own long arguments, and the honest position is that the evidence on ordinary consumption is far less alarming than the internet suggests and far less settled than the manufacturers suggest. Each has its own page. What matters here is narrower: for blood glucose specifically, they are not the thing raising it.

The practical order to read in

The added sugars line first, when you are comparing two similar products. It is the one that shows a choice.

The ingredient list second, and specifically its first few entries. Above the 1 percent mark the order is meaningful, so a syrup in the top three tells you more than any front-of-pack claim.

The front of the pack last, or never. “No added sugar” is a claim about one of the three places and says nothing about the other two. “Sugar-free” usually means the work is being done by sweeteners or sugar alcohols, and the sugar alcohols are the ones the panel may not quantify.