(updated from 12/8/2020)

If you are following a strict ketogenic diet, you may find that you read labels incorrectly, especially if you are in the UK (or Europe) and you follow US recommendations.

More and more often, we're contacted by people who have been following a ketogenic diet, sometimes for a few weeks, sometimes for months, but they are not getting the results they want, either losing weight or gaining vitality, even though they have reduced their intake of sugar dramatically.

​More often than not, this happens because they have been working out their carb intake incorrectly. During our consultation or a simple conversation, it appears that they are relying on information they think is true and apply to them, when, in fact, it doesn't.

Let me explain...

I want to start by saying that in ENERGISE: 30 Days to Vitality — Reset Your Body to its Natural Rhythm. Manage Blood Sugar and Energy Levels. Stamp down Inflammation. Gain Clarity. Detox and cellular Cleanse, we expose the great differences between the US and the UK.

Depending on your sources or books, these cannot be used by both nations because most books available in stores on the keto diet are majorly written for the American public (or people living in a country importing US-manufactured food or exporting food to the US).

Why doest it matter, I hear you ask...

You see, in the US, people are asked to count their carb intake, most importantly their 'net carbs', To calculate the net-carbs content of food, keto followers must use the following equation:

CARBOHYDRATE -FIBRE = NET CARBS

This is where it gets confusing.
In the US, a food label displays 'total carbohydrate', of which sugars and finally fibre.
US keto dieters thus must subtract dietary fibre because fibre is included in the total carbohydrate count.

Because the UK is still applying some old rules of the European Commission, labelling rules implemented in the US are irrelevant in Europe and so in the UK (unless clearly stated on the label).

Fibre is listed separately from carbs in Europe.

And so, in the UK (and in Europe) you do not deduct the fibre (or anything for that matter) from the carbohydrate total. This is how it is worked out:

TOTAL CARBOHYDRATE = NET CARBS

Let's make it clear again.

Fibre is included in the 'total carbohydrate' count in the US but you must not deduct the fibre if you are in the UK, because it is not included in the carbohydrate content.

But, it gets even more complicated.

Because, many long-life, processed and refined food products manufactured in the US are also found on supermarket and health store shelves in the UK, you may not know if you should deduct the fibre or not.

NUTRUNITY'S TIPS

If you're unsure and wonder if you should calculate the “net carbs” or rely on the carbohydrate content of food reading a label, look for the following:

1. Place of manufacture. A label must display the country where the product was manufactured, and if the food is imported, it must also provide the address of the reselling company and other contact details.

2. ‘Total Carbohydrates' or 'Carbohydrates', which clearly appears on the nutritional values label. If you read 'total carbohydrate', then it is likely to be an imported product and so you should subtract the fibre to establish the 'net carbs' content.

3. 'Fiber' or 'Fibre". If you read fiber, then it is likely an American product. If you read fibre then it is a British-made product and carbohydrates are interchangeable with net carbs.

4. Disproportional values. For example, Carbohydrate: 2.1 g. Fibre: 54.0g. Then you know that fibre is listed separately from carbs, and so the carbohydrate content is actually 'net carbs' content. And so the 'net carbs' = 2.1 g.

Looking at the above examples, this is a huge difference and quite a problem in itself.

Most ketogenic diets do not tolerate net carbs above 35 grams ('dirty keto' allows up to 50 grams and athletes up to 100 grams per day), and often only allow for around 25 grams of carbs per day. This means that there is an error of 1.2 g using the example above. That equals a discrepancy of 6.25% in your daily allowance. Repeat this a few times and you're likely to exceed your net-carbs limit and potentially failing to enter a state of ketosis.

It may also mean that you're mainly burning glucose rather than ketones for energy, and storing the extra energy as fat, especially if the diet is not accompanied by daily activity to reduce the available stores of glycogen.

IT DOESN'T END THERE!

There are more exceptions to the rule.
Sometimes you can accurately count your net-carbs intake and sometimes it's virtually impossible.
Sugar alcohols (e.g. sorbitol, mannitol, xylitol, erythritol, isomalt, maltitol, etc.) are largely found in all sugar-free/'Diet' products/chewing gums, yoghurts, ice cream, commercial salad dressings, protein bars and shakes, as well as regular fruits juices and many more food products.[1]

Sugar alcohols affect blood sugar levels, and so they must also be taken into account.

Common sugar alcohols found in foodstuff (although they occur naturally in some fruits and vegetables)[1,2,3]

• Erythritol (70% of the sweetness of sugar, but 5% of the calories) — made by fermenting glucose from cornstarch

• Xylitol (as sweet as regular sugar but 40% of the calories)

• Sorbitol (60% as sweet as sugar and about 60% of the calories) — commercially produced from glucose, sorbitol is also found in apples and pears and may be problematic for the many people who lack the enzymes to digest it, leading to bloating and digestive discomfort.

• Isomalt. Isomalt is a very strange one because it is a mixture of two sugar alcohols (mannitol and sorbitol) often extracted from sugar beet, and is usually used in the confection of candles and cake decorations, and in sugar-free chewing gums. Isomalt provides 50% fewer calories than sugar and 50% as sweet.

• Maltitol. Processed from maltose (a type of sugar), it’s 90% as sweet as sugar and almost half the calories. However, its glycaemic index (the response on blood sugar) is similar to table sugar and is best avoided on a keto diet.

Many foodstuff labels do not clearly list sugar alcohols and most often than not there is no indication of how much of it is used in the recipe. You may have to guess, using where it is found in the list of ingredients as a reference.
Ingredients are ALWAYS listed in order — listed in decreasing order, according to how much of it is used in the recipe. Ingredients appearing in the actual name of the product must be given a percentage, which also helps guessing the proportion of the rest of the ingredients.

Equations to use are thus:

NET CARBS (US) =

​TOTAL CARBOHYDRATES – FIBRE + (SUGAR ALCOHOLS ÷ 2) 

or

NET CARBS (UK) =

​CARBOHYDRATES + (SUGAR ALCOHOLS ÷ 2) 

If it wasn't enough, not all sugar alcohols are the same and it is with no surprise that erythritol is the favoured sugar alcohol among keto dieters, because it has a very negligible impact on blood sugar level.
Even though, Maltitol is a sugar alcohol, it has a glycaemic response similar to table sugar, which means it raises blood sugar in the same manner table sugar does — avoid it completely.
​
Glycaemic Index of common sugar alcohols:[4]

• Erythritol: 0

• Isomalt: 2

• Maltitol: 35–52

• Sorbitol: 9

• Xylitol: 7–13

• Table sugar: 60

Xylitol and other sugar alcohols contain fewer calories than table sugar but have an energy of 2.4 calories (2.4 kcal) per gram. Table sugar has 4 kcal per gram.
Divide the total sugar alcohol by two to roughly get your net carbs from the sugar alcohol content. This explains the “÷2” appearing in the above equations.

Make a rough estimate of the sugar alcohol weight to calculate calories if it is not clearly listed.
For example, let's look at the made-up nutrition label below.

Even though 'total carbohydrate' is shown on the label (we used US software to design the label - it should appear as “carbohydrates” on UK/EU labels), you can clearly see that the fibre content is well-above the 'total carbohydrate' and so you should not subtract the fibre content.

The total carbohydrate is, in this case, interchangeable with “net carbs”.
With the increasing popularity of the keto diet, many companies have resorted to incorporating sugar alcohols on the label. This is not mandatory and many companies don't bother...
Xylitol, a sugar alcohol, is clearly visible on the label above.
​
To calculate your net carbs you would use the following equation:

NET CARBS = CARBOHYDRATE + (SUGAR ALCOHOL ÷ 2)

6.0 g + (3.0 g ÷ 2) = 7.5 g net carbs

Unfortunately, labels like this are still very few and between. So let's try to make up an estimation based on the list of ingredients.
​89% of ingredients are already listed. Since the total weight is 360 grams, that's already 320 grams, leaving 40 grams for the remaining ingredients.

10% is 36 grams. So, we know that the pack contains 36 grams almonds and 36 grams Brazil nuts.
So, we also know that the percentage of the remaining ingredients weight just above 11 grams.
From expertise, we can assure you that any nutrients added are usually in milligrams (or even micrograms), which is negligible and should not be included (e.g. CoQ10, vitamins and minerals).
There is also more starch than xylitol, because starch is found before xylitol on the label.
We also know that xylitol is as sweet as sugar and so a little is needed to make the product sweet enough. You may decide on 7 grams of starch and 4 grams xylitol for example. It is not ideal but it can help you estimate your net carbs, so you don't go over the limit.

In this particular example, you have a discrepancy of 0.5 g net carbs. It is quite significant if your limit is 25 grams per day. But, by doing so, you can stay under the 25 grams, even if you are maximising your net carbs for the day. So it is not such a bad thing.

Surely, this is it… Right?

Well, we need to keep in mind recent events and Brexit is a major game changer. The UK is heading towards a wall, and a no-deal Brexit is likely to be the outcome the current government is relentlessly aiming for.
We already know that the US and the UK have had talks about the future of the food market in the UK and we should expect chlorinated chicken and hormone-grown beef (and the rest, including unlabelled GMO foods) to inundate our shops the day after the UK has left Europe.
So, watch out for labels because you may, after all, have to work out the net carbs by subtracting the fibre from the total carbohydrate content.

You may also have to check where the food comes from and what is truly inside, including GMOs and other questionable ingredients.

​References:

1. ​Chattopadhyay, S. Raychaudhuri, U. Chakraborty, R. (2014). Artificial sweeteners - A review. Journal of food science and technology, 51(4), pp. 611–621. https://doi.org/10.1007/s13197-011-0571-1

2. Lenhart, A. Chey, WD. (2017). A Systematic Review of the Effects of Polyols on Gastrointestinal Health and Irritable Bowel Syndrome. Advances in Nutrition (Bethesda, Md.), 8(4), pp. 587–596. https://doi.org/10.3945/an.117.015560

3. Browne, CA. et al. (2016). Detection and identification of sugar alcohol sweeteners by ion mobility spectrometry. Analytical methods: advancing methods and applications, 8(28), pp. 5611–5618. https://doi.org/10.1039/c6ay01554a

4. Chattopadhyay, S., Raychaudhuri, U. Chakraborty, R. (2014). Artificial sweeteners — A review. Journal of food science and technology, 51(4), pp. 611–621. https://doi.org/10.1007/s13197-011-0571-1