What are the risks of cellulose?

November 26, 2025 •

4 min read

The U.S. Food and Drug Administration generally recognizes cellulose as safe for consumption, but potential risks exist depending on its form and application. This article explores what are the risks of cellulose, examining its use in food, insulation, and as a nanomaterial.

Quick Summary

This article examines the risks associated with cellulose, differentiating between dietary fiber and industrial uses like insulation. It details potential health effects from overconsumption or inhalation and explores specific concerns with processed forms.

Key Points

Dietary Overconsumption: Excessive intake of any fiber, including cellulose from supplements, can cause digestive issues like bloating, gas, diarrhea, or constipation.
Gut Microbiome Alteration: Rodent studies suggest certain modified cellulose additives, like cellulose gum (E466), may alter gut flora, potentially promoting chronic intestinal inflammation and metabolic syndrome at high levels of consumption.
Inhalation Hazard: Inhaling fine cellulose dust from insulation can cause respiratory irritation, especially during installation, though it is generally considered less hazardous than fiberglass.
Industrial Chemical Additives: Cellulose insulation is treated with fire-retardant chemicals like ammonium sulfate, which can become corrosive and form sulfuric acid if the insulation gets wet.
Processing Adds Risks: The safety of cellulose varies significantly depending on its form—natural whole food fiber is generally safe, while modified additives and industrial materials carry specific, additional risks.
Potential for Reduced Nutrient Absorption: Very high doses of cellulose gum might interfere with the absorption of certain nutrients and medications.
Nanocellulose Uncertainty: The long-term effects of ingesting nanocellulose materials found in some food contact materials and additives are not yet fully understood and require more study.

Cellulose is an organic compound that forms the primary component of plant cell walls, and as such, it is a key part of the human diet. As an insoluble fiber, it passes through the human digestive system largely undigested, adding bulk to stool and aiding digestive regularity. However, the term "cellulose" also applies to modified forms used in food additives, supplements, and industrial materials like insulation, where potential risks can arise.

Health Risks Associated with Dietary Cellulose

For most people, cellulose obtained from whole plant foods like fruits, vegetables, and grains poses no risk and is beneficial for health. Risks related to consumption typically arise from overconsumption, especially via supplements or highly processed foods with added cellulose.

Overconsumption and Digestive Discomfort

An excessive intake of fiber, including cellulose, can lead to several uncomfortable digestive issues. These are most likely to occur when fiber intake is increased too quickly or without sufficient water intake.

Bloating and Gas: As insoluble fiber passes through the digestive tract, it can cause increased gas production and bloating.
Constipation or Diarrhea: While fiber generally promotes regularity, too much can either cause blockages or have a laxative effect, especially in modified forms like cellulose gum.
Stomach Cramps: High fiber intake can sometimes lead to stomach upset and cramping.

Concerns with Modified Cellulose Additives

Processed and modified forms of cellulose, such as cellulose gum (E466 or carboxymethylcellulose), are used as thickeners, emulsifiers, and stabilizers in thousands of food products, from dressings to ice cream. Emerging research has raised questions about their long-term effects on the gut.

Altered Gut Microbiome: Rodent studies suggest that long-term, high consumption of cellulose gum can alter the gut microbiome, potentially leading to chronic inflammation, metabolic syndrome, and even increasing the risk of colon cancer. While human studies are still limited, a 2021 study on humans showed significant microbiome changes after consuming cellulose gum, warranting further research.
Reduced Nutrient Absorption: Large quantities of cellulose gum might interfere with the absorption of certain nutrients, such as calcium and magnesium, due to its binding properties. Fiber supplements can also reduce the efficacy of some medications.
Cardiovascular Health: A 2023 study suggested a link between higher consumption of cellulose gum and an increased risk of cardiovascular disease.
Allergic Reactions: Although rare, some individuals may have allergic reactions to cellulose or its derivatives, resulting in symptoms like skin irritation, hives, or breathing problems.

Industrial and Inhalation Risks

Cellulose is a primary component in building insulation, where it is made from recycled paper products and treated with fire-retardant chemicals. The risks in this application are distinct from those involving food.

Inhalation of Dust: During the installation or removal of cellulose insulation, fine airborne particles can become present. While not as dangerous as fiberglass, inhaling cellulose dust can cause significant respiratory irritation, particularly for those with existing allergies or sensitivities. Personal protective equipment, like N95 masks, is recommended for installers.
Fire Retardant Chemicals: The fire retardants used in cellulose insulation, such as boric acid, sodium borate, and ammonium sulfate, carry their own set of risks. Ammonium sulfate, if it becomes wet, can decompose and produce corrosive sulfuric acid, which can damage metal components like pipes and trusses.
Occupational Exposure to Nanocellulose: The increasing use of nanocellulose materials in manufacturing raises concerns about occupational inhalation exposure. The potential hazards of this exposure are still being evaluated, and data gaps exist concerning long-term effects and toxicity.

Comparison of Cellulose Forms and Risks

To better understand the risks, it is helpful to compare the different contexts in which cellulose is encountered.


Feature	Whole-Food Cellulose	Modified Additive Cellulose	Industrial Cellulose (Insulation)
Source	Plants, vegetables, grains	Wood pulp, cotton, plant waste	Recycled paper (newsprint)
Form	Naturally occurring fiber	Microcrystalline, cellulose gum	Fluffy, shredded fiber
Primary Function	Digestive health, adds bulk	Thickener, stabilizer, filler	Building insulation
Caloric Value	Zero calories	Zero calories	N/A
Consumption Risks	Very low; tied to overconsumption of dietary fiber.	Digestive upset, potential gut microbiome changes, processed food link.	Inhalation hazard of dust.
Chemicals Involved	None, in pure form.	Acetic acid, salt, other modifiers.	Fire retardants (borates, ammonium sulfate).
Absorption	Passes through digestive system.	Passes through, but may affect nutrient absorption.	Inhalation risk, not digestive.

Conclusion: Context is Key for Cellulose Risks

The risks of cellulose are not uniform and depend heavily on its form and application. Naturally occurring cellulose from whole foods is a healthy and safe part of a balanced diet, with the only real risk stemming from excessive intake causing minor digestive issues. However, the use of modified cellulose as a food additive introduces potential, though not fully understood, long-term risks related to gut health and nutrient absorption, primarily linked to the broader consumption of highly processed foods. Finally, industrial applications, such as insulation, carry separate and specific risks, particularly related to the inhalation of fine dust particles and exposure to chemical fire retardants. For informed decision-making, it is important to consider the context and type of cellulose, and to read ingredient labels, especially when consuming highly processed products. Further long-term research is needed to fully assess all the potential risks associated with modified and nanoscale cellulose materials. You can find more information about food additives from reputable sources such as the Center for Science in the Public Interest: www.cspi.org/chemical-cuisine/cellulose.

Note: The FDA (Food and Drug Administration) classifies cellulose as GRAS (Generally Recognized as Safe), indicating it has been deemed safe for consumption based on available data. However, this does not eliminate all potential risks, particularly for sensitive individuals or with excessive intake.

Frequently Asked Questions

The amount of powdered cellulose used as an anti-caking agent in shredded cheese is generally considered safe and is a negligible source of dietary fiber. The FDA recognizes it as safe for consumption.

While rare, it is possible to have an allergic reaction to cellulose or related compounds. Symptoms can include skin rashes, respiratory issues, or gastrointestinal problems.

The main risks associated with cellulose insulation include respiratory irritation from inhaling fine dust during installation and potential corrosion risks from fire-retardant chemicals, particularly if the material becomes wet.

Some research, primarily in rodents, suggests that high consumption of cellulose gum (E466) may alter the gut microbiome and potentially trigger chronic inflammation. This area is still under investigation, especially for long-term human effects.

In large, supplemental quantities, cellulose gum has been observed to potentially hinder the absorption of certain minerals like calcium and magnesium. This is not a typical concern with naturally occurring cellulose from whole foods.

While not as acutely toxic as some other materials, breathing in fine cellulose dust can cause respiratory irritation, especially in sensitive individuals. It is recommended to use an N95 mask during installation or removal to protect your lungs.

No, avoiding all cellulose is unnecessary and would mean cutting out many healthy plant foods. Concerns are mostly related to high intake of modified forms in highly processed foods. Focus on obtaining fiber from whole foods and read labels on processed items.