What are these sugar alcohol ingredients in protein bars?

Posted by Dayne Hudson in Weight Loss

Estimated reading time: 4mins

What is in Protein Bars?

Are low carb protein bars efficient?

First things first, a little window dressing for context.

Carbohydrates for years were tagged as the macronutrient responsible for fat loss. There were bogus theories that because carbohydrates spike insulin (which inhibits fat accumulation) eating them must be bad.

But it's not that simple. And when we put it to the test, we saw that just because fat burning can be turned off during carbohydrate consumption, it doesn't mean that we still can't eat even 100% of our diet from them -- whilst in a calorie deficit -- and lose weight.

Fat loss ultimately comes down to one thing: a deficit of calories.

This is otherwise referred to as the "carbohydrate-insulin hypothesis of obesity." And despite being proven wrong many times, it still persists. One of the many reviews to disprove this bogus theory included 32 studies that found low carbohydrate or high carbohydrates diets make no difference to fat loss.

Insulin isn't a factor, and if it were, we'd be putting on weight from whey protein -- which is actually more insulinogenic than white bread!

Ok, so that's that.

And so many brands took to "low carb" options at the height of this.

But now I will say, low carb foods are still helpful, as we can get our carbohydrates from other sources and/or later on.

Maltitol, glycerol and sorbitol

These are the common sugar alcohols in protein bars, and are present for three reasons:

  • They add sweetness
  • Have fewer calories than sugar
  • Help to improve the texture of bars and help to retain moisture.

But what about their caloric value?

Maltitol = 2.1 calories

Glycerol = somewhere between 1.98 to 2.26 calories

Sorbitol = 2.7 calories

Now, remember carbohydrates (and thus sugar) have a value of 4 calories per gram. So 50 per cent of the calorie value of sugar ain't bad.

So when you're tracking your macronutrients, just make sure for every 2 grams of any sugar alcohol, you count it as a gram of carbohydrates.

White sugar on a spoon
When you're tracking your macronutrients, make sure for every 2 grams of any sugar alcohol, you count it as one gram of carbohydrates.

So for example:

Maltitol = 3 grams

Glycerol = 5 grams

Sorbitol = 7 grams

Total = 15 grams (so 7 grams of carbs).

Now it's not going to break your diet. But if you're having a few of them, and having other snacks where these sugar alcohols exist, then you just need to be aware of it.

But as I've said in a previous blog -- don't consume these bars thinking they are any "healthier".

Seriously, just eat a chocolate bar (most have fewer calories than protein bars anyway) and consume your protein shake with it, to get the best of both worlds: the protein, plus the snack.

Where you can, forget sugar alcohols, and just have real sugar if you want it.

But, these sugar alcohols are all converted into glucose anyway.

When you're getting enough fibre daily, and vitamins and minerals, a chocolate bar in concert with your active lifestyle isn't going to destroy you or your progress.

It's all about balance.

Here's a look at the other sugar alcohols and their caloric value (note the "Caloric value (kcal/g)" to the right of the table).

Are sugar alcohols safe?

Like most things, unless they are consumed in a large dose, they appear to be perfectly fine.

One study concluded:

"The available clinical data generally suggest that moderate consumption of the above polyols (sugar alcohol) is not harmful to human metabolism."

Research suggests it could create some IBS issues, so if you notice this, then like anything, stop eating it.

At this stage there’s no major concerns over the safety of sugar alcohols.
At this stage there’s no major concerns over the safety of sugar alcohols.

The bottom line on sugar alcohols

Is those sugar alcohols like sorbitol, maltitol and glycerol are about half the caloric value of sugar, but not as sweet. They are also present to help improve the texture of bars and help to retain moisture. They're safe to eat in the doses they are found, but if they give you too many bathroom visits, stop consuming them. Just be aware of their macronutrient/calorie value if you're consuming a lot of them. If you're consuming them over a chocolate bar, just eat the chocolate bar, and have a protein shake with it. The calories will more or less be the same.


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group of product images for proteins
group of product images for proteins