When working with Alchemist Eating clients (or planning my own meals), I start with some basic primal parameters:
1. Eat real, whole food: I’m talking high-quality meat, fish and eggs; healthy fats and oils; lots of veggies; and moderate amounts of fruit, nuts and seeds. (For some people, high-quality, full-fat dairy is okay too, as are “occasional, sensible indulgences,” such as dark chocolate.)
2. Avoid: grains, legumes, processed food, added and artificial sweeteners, and chemically altered fats and oils.
From there, I add, subtract and tweak based on individual needs and Chinese Medicine food therapy.
But the question often arises: “What about (insert your questionable food, beverage or supplement here) ???”
Sometimes the answer is straightforward. Sometimes it falls in a grey zone.
So…last week I introduced a “What about” series, where I’ll take on those “What about” questions one-by-one. First up was stevia, which led one reader to ask…
What about xylitol?
Ahh…another darling of the low-carb, sugar-substituting crowd. You’ve maybe spotted it in sugar-free chocolate bars…or chewing gum or toothpaste.
What is this strange-sounding sweetener of which you speak?
Xylitol is a “sugar alcohol,” a type of low-digestible carbohydrate. The “low-digestible” bit refers to the fact that sugar alcohols aren’t broken down so well in our small intestine.
Upon reaching the large intestine, colonic bacteria ferment them. In this way, sugar alcohols are similar to another low-digestible carb: fiber.
Sugar alcohols, also known as polyols, are found naturally in many fruits, vegetables and hardwoods. Along with xylitol, other popular ones include erythritol and sorbital (see Mark Sisson’s great post here). Most commercial xylitol comes from hardwood and genetically modified corn.
Xylitol tastes similar to sucrose (table sugar) yet is 1.6 times as sweet with half the calories. It causes negligible changes in blood glucose and no changes in insulin levels.
What’s more, xylitol has been shown to support dental health, helping prevent tooth decay and plaque formation. This action, combined with its cooling mouth feel, makes it the sugar-sub of choice for “naturally sugar-free” gum and toothpaste. Xylitol also seems to support bone re-mineralization, both in teeth and generally.
Sounds great, right? A low-calorie, cool-sounding sweeter that battles cavities and boosts bone health.
Yeah, but…how do they make the stuff in my chewing gum?
As often the case with sugar-fix “quick fixes,” that’s a key question. And xylitol is no different.
The stuff you’re consuming in packaged goods is not the stuff found in an apple.
Extracting the sugar crystal xylitol requires a chemical process. Most commonly, this involves taking xylan—the source material—from genetically modified corn and breaking it down through acid-hydrolization using nickel-aluminium as a catalyst. This leaves us with xylose and acetic acid.
To remove the (very hazardous) acetic acid, as well as residual hydrolyzing acid and nickel-aluminium, the mixture goes through another heating and evaporation process. Ethanol is then added so the xylitol takes a stable, crystallized form. Then, to separate the crystallized xylitol from the ethanol, the combination is spun in a centrifuge.
Um. Okay. If you caught even part of that, our darling xylitol is probably looking a little less au naturale. But still not all bad, right?
And, anyway, how the heck does crystalline xylitol affect the gut?
Yeah. Another good question. Because although sugar alcohols seem safe and may offer health benefits, they are often cause for digestive duress.
Remember how I said sugar alcohols—including xylitol—are also called “polyols”? That makes them a FODMAP (fermentable, oligosaccharides, disaccharides, monosaccharides and polyols).
If you’ve been diagnosed with “SIBO” (small intestine bacterial overgrowth), you likely know about these FODMAP characters and do your best to avoid them.
In brief, they are carbs that some people can’t fully digest in the small intestine (and, when it comes to low-digestible sugar alcohols, this is the case generally).
So…poorly digested sugar alcohols find their way to the colon, where they become food for colonic bacteria. As these bacteria break down and ferment them, a lot of gas is produced.
Aside from gas, this can also cause bloating, discomfort and decreased fat absorption from other foods. Plus, because sugar alcohols are largely undigestible, they can cause diarrhea by pulling water into the colon.
If you can hold out, these side effects may subside. Studies suggest that people adapt to regular sugar alcohol consumption over time (which makes sense, given our gut flora’s knack for gradual adaptation in response to the foods we eat).
The amount of xylitol you consume is another crucial factor. A stick of xylitol-laced gum? Probably not a problem. Five xylitol-sweetened chocolate bars? Probably not the best plan.
Of course, if you do have SIBO, IBS or other gut problems, proceed very, very cautiously.
Consuming xylitol—even in small amounts—may make digestive distress and other symptoms worse.
Great. So I guess I’ll just feed the rest of that yummy-tasting, gas-inducing, diarrhea-causing xylitol bar to my cat, right?
WRONG!!! Xylitol is deadly toxic to many animals, so keep it away from your cats, dogs and other furry friends.
And, as with stevia, we must end with that dreaded question…
Are you feeding a sugar habit? Or using the “xylitol’s okay excuse” to consume processed “low-carb, low-sugar” treats?
For those trying to break a sugar cycle, adding another sweet substitute will just make things worse. Sure, it may not induce a blood glucose or insulin spike (unless, uh, you’re eating it inside a decidedly off-limits, non-paleo, grain-based processed treat).
But it also won’t help re-sensitize your taste buds to the natural, less extreme sweetness of real foods (and by “real,” I mean whole veggies, whole fruits and even meat—not isolated, chemically processed “natural” food-like substances).
A little xylitol may be okay and may even have health benefits (depending on what else is along for the ride in that sugar-free candy bar).
But, as with any sweetener, more than a little feeds the sugar demon and hinders efforts to change unhealthy eating patterns.
Plus, in the case of xylitol, more than a little may cause bloating, gas, diarrhea and cramping (better to just indulge in a spoonful of raw honey, if you ask me).
So…what about xylitol? Here’s my take, in short form:
1. Best to steer clear of sugar substitutes, particularly ones that are highly processed (or are contained in processed foods). This is doubly true if you’re trying to break a sugar habit, restore sensitivity to the natural sweetness of real foods, and transform eating patterns.
2. That said, a little xylitol is not the worst choice and may offer benefits, particularly for dental health. It’s a far better choice than artificial sweeteners like Splenda and Sweet’N Low. Just don’t use the “xylitol’s okay excuse” to consume processed “low-carb, low-sugar” treats—that stuff is not real food, not paleo-primal, and not good for you.
3. If you do use xylitol, start slow and be on the watch for any gastro-intestinal side effects, such as bloating, gas, cramping or diarrhea. If you have SIBO, IBS or other gut issues, proceed super-duper carefully—xylitol will likely make symptoms worse.
4. Xylitol is deadly toxic to many animals, so keep it away from cats, dogs and other furry friends.
Got your own “What about” questions? Ask away!