Thickeners are one of many ingredients added to processed foods. And they do just that: thicken. They absorb water and form a gel-like consistency. They’re often used to make foods thick and creamy, without having to add a lot of fat.

Thickeners also tend to emulsify and stabilize foods they're added to. Emulsification allows fats and water to mix better and prevents them from separating (i.e., oil/vinegar salad dressing versus a thicker or creamier emulsified dressing). And "stabilizing" helps the product have a longer shelf-life before the "best before" date.

Thickeners are often found in canned dairy-free milk and any milk that comes in a carton, baked goods, soups/sauces/gravies, mac and cheese, puddings/ice cream, etc. Some are even added to dietary supplements!

These thickeners are polysaccharides, which means they're long chains of many (poly) sugars (saccharides). They're typically difficult to digest, which makes them similar to dietary fiber. And this also means they can help you feel fuller longer without providing many calories or any nutrients.

They're naturally-derived but are heavily processed to extract the compound. 

FUN FACT: food additives are considered anti-nutrients because they reduce the absorption of dietary minerals like calcium.

Overall, for the general healthy population, in small doses, these thickeners don't seem to create massive health concerns. But, even though they're extracted from whole foods, they're far from it. 

Let’s briefly dive into five of the common thickeners.

Xanthan Gum

Xanthan gum is made by a bacteria called Xanthomonas campestris. The xanthan gum is created when the bacteria ferment sugar. Xanthan gum is extracted from the liquid, dried, and ground.

Because it's like dietary fiber, xanthan gum has been shown to help reduce blood sugar spikes. Its thickening properties can help slow the absorption of sugar, therefore slowing the speed sugar can get into the bloodstream.

In high doses, xanthan gum can act as a laxative and can cause bloating, gas, and diarrhea. It also may act as a prebiotic (food for our friendly gut microbes), but more research is needed.

Xanthan gum should be avoided by infants and people with severe wheat, corn, soy, or dairy allergies.

Guar Gum

Guar gum is made from legumes called guar beans. These beans are split, and the endosperm is ground to get the guar gum.

Like xanthan gum, guar gum may reduce blood sugar spikes, act as a laxative, and possibly act as a prebiotic.

In rodents, guar gum has been shown to increase intestinal permeability (i.e., leaky gut). 

Cellulose Gum

Cellulose gum is made from wood pulp and cotton. To extract the cellulose gum, the pulp is processed with several chemicals, which are then removed.

Cellulose gum can cause bacterial overgrowth and inflammation in animals who eat large amounts of it. It’s been suspected to be linked with IBD (Inflammatory Bowel Disease).

Carrageenan

Carrageenan is made from red seaweed that's dried, ground, chemically treated, filtered, and dehydrated.

Carrageenan can increase intestinal permeability (i.e., leaky gut). It has been linked to gastrointestinal inflammation, ulcers, and colitis-like conditions in animals. It has also been used in high doses to cause tumors in animals for cancer research.

Unlike other thickeners, some rodent studies have shown that carrageenan can worsen blood sugar control issues.

Lecithin

Lecithin most often comes from soybeans, but can also come from eggs, canola, or sunflower seeds. It's heavily processed with chemicals and then purified.

Lecithin also contains phospholipids, triglycerides, sterols, free fatty acids, and carotenoids.

One of lecithin's metabolites (what your body metabolizes lecithin into once it's absorbed) is linked to heart disease. On the other hand, it does lower serum cholesterol. Overall, the jury seems to be out on its heart health effects.

Thickeners are highly processed food additives derived from nature. They are found in many processed foods because they thicken, reducing the amount of fat needed.

In the body, they can act as a dietary fiber and may have some of the health benefits of that. But, they can also contribute to gastrointestinal issues, especially in higher doses. They can also be allergenic in small doses.