The Truth About Sugar Alcohols

Are sugar alcohols a good choice for Atkins?
What are the advantages and disadvantages?

Sugar alcohols are quite popular within the low-carb community. These sugar alternatives taste like sugar, add bulk like sugar, and even caramelize when heated. Yet, they contain fewer calories than traditional sweeteners.

Even better, according to the Atkins rules since 2002, you don't have to count them when doing Atkins because sugar alcohols do not significantly impact your blood glucose levels.

Sound too good to be true?

Yep. It is.

Atkins.com has clarified their stance to:

"fibre and sugar alcohols minimally impact blood sugar levels at the doses present in the products."

However, the rules of using sugar alcohols during Atkins Induction and Phase 2 of the Atkins Diet still haven't changed.

If you're on Phase 1 of Atkins 20, you're instructed to subtract all fiber and sugar alcohols from the total carbohydrates listed on the package, even though they do impact blood sugar.

Over the years this practice has been known as finding the "net" carbs for the ketogenic food you want to eat.

Net carbs are based on the theory that fiber and sugar alcohols are not metabolized by the body in the same way that sugar and starches are, so you don't have to consider them when counting out your 20 net carbs for Induction.

Unlike other carbohydrates, sugar alcohols were thought to not raise blood sugar, and therefore, not raise insulin.

In 2002, when Dr. Atkins first suggested this idea to his readers, glycemic index studies were still in their infancy. What research scientists overlooked at that time was the fact that these studies were:

1. Performed on folks with a healthy blood glucose response to carby foods; and
2. Insulin secretion, due to eating, doesn't always correlate with blood glucose elevation.

To try and correct these oversights, those conducting the glycemic index studies started looking into the glycemic load of foods, which takes the carbohydrate content of each food into the formula, instead of just using the glycemic index.

Later on, it was discovered that insulin secretion didn't run parallel to glucose elevation, so studies started looking at which foods secrete insulin even when your blood glucose didn't rise.

And guess what?

Yep.

Sugar alcohols cause insulin secretion because insulin is necessary to process them.

This isn't bad. But it is something that you need to know.

The glycemic index appears to be a useful tool for those who don't have metabolic syndrome or diabetes, but it isn't an accurate tool for those who do.

So with that in mind, this post is going to take a closer look at sugar alcohols and how to use them responsibly on a low-carb diet.

What are Sugar Alcohols?

Sugar alcohols are a polyol found in various natural foods, such as produce, sweet potatoes, and some grains. These alcohol structures can be artificially formed by manufacturers through the use of extractions, enzymes, and fermentation.

Unlike how the name sounds, this sugar alternative doesn't have any ethanol, so you can't get drunk eating sugar alcohols, but they do contain similar structures as those found in sugar and alcohol.

Compared to sugar, they contain fewer calories and carbohydrates, and since they convert to glucose more slowly than other carbs, they are thought to be a good choice for weight loss, insulin resistance, pre-diabetes, and diabetes management.

But these assumptions can be misleading.

Is Sugar Alcohol Bad for You?

Different types of carbohydrates affect blood sugar levels differently, depending on how quickly the body breaks them down into glucose after you eat.

Carbs that produce a lot of glucose take a lot of insulin to process, especially if you happen to be insulin resistant or a Type 2 diabetic.

The most familiar carbs that digest quickly are sugars and refined starches, which elevate blood sugars in those with pre-diabetes or diabetes. Basic insulin levels, the insulin your body secretes every few minutes whether you eat or not, will also rise if you consistently eat too many carbs.

But there are some foods and ingredients that can trigger insulin secretion even if your blood glucose doesn't rise.

These foods are said to be insulinogenic.

If you're insulin sensitive and you eat something that is insulinogenic, your blood sugar will go down, due to the temporary insulin elevation.

The extra insulin tells the liver that there is extra glucose available, even when it's not.

As a result, the blood glucose falls too low, triggering stress hormones, which then tell the liver to convert glycogen into glucose and dump it into the bloodstream. Fat mobilization is temporarily put on hold because more insulin is secreted to handle the glucose dump.

For those who are insulin resistant, the body won't respond well to the insulin secreted, but whether that's a problem depends on how much insulin you have running around already and how insulin resistant you are.

High insulin itself will make your cells even more insulin resistant, so theoretically, you could make the insulin resistance worse.

In addition, sugar alcohols in general have a laxative effect.

The delay in digesting them often causes serious gastric symptoms, such as bloating and/or diarrhea. In fact, if you don't have such reactions to eating them, it's likely due to the fact that your body is digesting them as if they were sugar.

But sugar alcohols can also function as a prebiotic. Since they take so long to break down in most folks, if at all, digestion often doesn't occur until they reach the colon.

Erythritol, on the other hand, is fully absorbed by the small intestine, but not metabolized because the body has no clue what to do with it. Since it's a foreign substance made from cornstarch, it is generally sent to the kidneys for excretion.

Do You Need to Count Sugar Substitutes in Your Net Carbs?

When folks talk about available carbohydrate, they are generally referring to all carbs except fiber, since most people don't digest fiber and cellulose. However, that isn't true for everyone.

Some people do break down fiber during digestion. If you happen to be one of them, you'll have to count total carbs instead of net in your daily totals.

The U.S. determines carbohydrates "by difference."

Manufacturers measure protein, fat, water, and ash in 100 grams of food, subtract that amount from 100, then assign the label of carbohydrate to everything else.

This method of determining carbohydrate content of foods can make it difficult to analyze just how much available carbohydrate any particular food and product actually has.

Today, Atkins Nutritionals, Inc., as well as other low-carb product manufacturing companies, continue to insist that it's the net impact carbs that count, rather than all carbs. Impact carbs means that in addition to the actual fiber content of food, they also want you to subtract:

• glycerin
• sugar alcohols
• and polydextrose

The claim is that these chemicals have a negligible effect on your blood sugar level, and therefore, they don't belong in your carb calculations.

But is that really true?

Diabetes expert, Madelyn L. Wheeler doesn't think it is. In her professional opinion:

". . . some of the sugar alcohols and fiber are absorbed by the body. In fact, about half of the grams of sugar alcohols are metabolized to glucose."

Did you catch the part about some of the fiber you eat being absorbed by the body? And that half of the grams of sugar alcohols can be metabolized to glucose? I don't know if this is peculiar to those with diabetes or not, but it's definitely something you need to be aware of.

The fiber in foods isn't just found in produce. Manufacturers often add fiber to their products in the form of:

• cellulose
• xanthan gum
• flaxmeal
• pysillium husks

And other fibers. This is becoming extremely common among gluten-free food manufacturers, which is also spilling over into the low-carb market.

Deducting all of that can be misleading, especially for those who have to inject insulin.

I found it hard to believe that the ability to break down fiber was peculiar to just diabetics, so I read what she wrote about how to correct the insulin dosage for fiber and sugar alcohols because I thought it would give you a clearer perspective on net carbs.

Her recommendation was to separate insoluble fiber from soluble fiber, which is exactly how Dr. Atkins originally said to do this in 1999! She then had you deduct all of the insoluble fiber in a product from the total carb count, same as Atkins.

Here's where they part ways:

If there was more than 5 grams of soluble fiber still left, you deducted half of that fiber count to arrive at the correct net carb figure. This means that glucose is produced when you eat soluble fiber, which takes insulin to process, so diabetics have to inject additional insulin to make up for those carbs.

For insulin purposes regarding sugar alcohols, you keep the first 5 grams of sugar alcohol in your net gram calculation. You can't deduct those. Then, for amounts over 5 grams of sugar alcohols, you can deduct half of those carbs.

The only exception to this:

If there is just erythritol in the product you're considering and no other sugar alcohol, can you subtract all of the carbs to arrive at your net carb figure.

This means that the body absorbs and breaks down sugar alcohols to some extent, except for erythritol, which isn't digested by anyone. The only sugar alcohol that you can confidently deduct all of the carbs for is erythritol.

This explains why erythritol is the most popular sugar alcohol among dieters.

Now, this doesn't mean you can't have an adverse reaction to the erythritol. It's a foreign substance, which is absorbed into the bloodstream, so it might be problematic for those with autoimmune issues or those who don't absorb well.

At one time, I was severely reacting to erythritol, but today, I am able to use small amounts of it without it bothering me.

In fact, in my latest tests on CarbSmart ice cream, 1 cup of CarbSmart ice cream raises my blood glucose by 6 mg/dl. That's far less than digesting 50 percent of the carbs, but it's not a no-impact food for me, either.

Glycemic Index and Sugar Alcohols

In 1999, sugar alcohols of any type were not allowed on Atkins, but with the 2002 version of the diet, things changed.

The new recommendation was that all carbs that didn't impact blood sugar didn't have to be counted when doing Atkins. At that time, this meant all fiber and all sugar alcohols.

Today, this has been reinterpreted as meaning:

• all fiber
• all sugar alcohols
• glycerin
• and polydextrose

However, if this is true, that sugar alcohols, glycerin and polydextrose are non-blood sugar impacting carbs, then wouldn't the glycemic index value be flat-out zero?

Only TWO of the sugar alcohols have a glycemic index of zero.

Several of the others have a very low GI value, and two have extremely high GI values -- higher than 50 -- which essentially makes them very comparable to regular table sugar. Table sugar has a value of 62.

Here are the GI Values of Sugar Alcohols

Maltitol Syrup = 48 to 53 with regular syrup = 52
Polyglycitol (hydrogenated starch hydrolysate) = 39
Maltitol Syrup (high polymer) = 36
Maltitol = 36
Xylitol = 13
Isomalt = 9
Sorbitol = 9
Lactitol = 6
Erythritol = 0
Mannitol = 0

Notice that Erythritol and Mannitol are the only sugar alcohols that have no impact on blood sugar. Lactitol, Sorbitol, Isomalt, and Xylitol have a very small impact.

Maltitol has a huge impact on blood sugar and is the most common sugar alcohol that you'll find in low-carb products. However, this is beginning to change. More and more manufacturers are switching to a combination of erythritol and other sweeteners.

Maltitol crystals and/or syrup are the most commonly used sugar alcohols -- think Russel Stover chocolates, sugar-free chocolate chips, and other sweetened low-carb foods.

No matter what a low-carb company says, Maltitol does have a significant impact on blood sugars. It's almost as much as regular table sugar, so you'll want to stay away from anything that contains Maltitol.

Erythritol and mannitol supposedly have NO EFFECT, so they are used most often by diabetics.

Also acceptable would be Truvia, which is over 99 percent Erythritol, Swerve, and other products that combine Erythritol with Stevia.

Keep in mind, I'm only talking sugar alcohols here.

If you want a complete list of all sugar substitutes, check out our post on the truth about sugar substitutes. It goes into more detail than I do here about other sweeteners and gives you their GI value, as well.

The other sugar alcohols have a "minimal" effect, so use some common sense when it comes to adding them to your diet. Start very slow and watch for gastrointestinal issues to crop up.

Some people can get away with a teaspoon here or there with no problems, but cannot handle a full-serving of dessert made with them.

Since vegetables come with a GI value of about 15, or less, I'm including Xylitol in the list of acceptable sugar alcohols, but honestly, all of them need to be used sparingly. Even Erythritol will cause your weight loss to stall if you are eating too many low-carb baked goods and desserts.

While I can understand having a sweet treat now and then, don't forget your purpose for going low carb. Trying to recreate the diet that got you fat in the first place is playing with fire.

So What About Glycerin and Polydextrose?

Glycerin is a liquid by-product from making soap. It's used in low-carb cooking to keep ice cream soft and scoopable.

A serving of 75 grams has a negligible effect on blood sugar in normal individuals, but if you have Type 2 diabetes, with an overactive liver, due to insulin resistance, it can most certainly give you problems.

Polydextrose is another sugar alcohol that is used a lot in low-carb cooking and products to keep things soft and provide bulk. It can help give baking results that mimic the characteristics of sugar, like stickiness and browning.

A study reported in the American Journal of Clinical Nutrition in December, 2000, confirmed that it, too, has a negligible impact on blood sugars. It is essentially non-glycemic.

However, scientific research isn't all that reliable. It tests these kinds of things on a certain group of individuals, and your reaction to polydextrose might be completely different than their test group.

Additional Cautions and Tips

Make sure that you are checking the labels of the low-carb products that you buy and use. Don't just grab something because it says, "Low Carb" or "Atkins," without verifying the type of sugar alternative in the product.

Sugar alcohols are being used more than they ever were before.

So much so, that they are even finding their way into mainstream products like:

• toothpaste
• chewing gum
• breath mints
• mouthwash
• and throat lozenges

Anything that says, "sugar free," is suspect, but anything that normally contains sugar is suspect, as well. It doesn't have to be a diet product.

While sugar alcohols are naturally found in common foods, such as pineapple, olives, and asparagus, most manufacturers don't extract it from everyday foods. They will extract it from corn.

That doesn't mean that sugar alcohols are bad. They come with advantages and disadvantages.

But it does mean that you need to be careful.

Make the effort to watch how your body reacts when you use them. Write it down in a journal, if you need to. Sometimes, the effects of stress doesn't show up for a couple of days and writing things down helps you spot patterns.

Go ahead and record any advantages that you see, as well. I'm definitely not a no-treats person.

But above all, be honest and sincere. Lying to yourself about how sugar alcohols really affect you only harms yourself. No one is going to see what you write, so be brutally honest.

The aim isn't to find justifications for kicking sugar alcohols out of your life. The aim is to recognize them for the treat that they are.