What are the side effects of bulking agent INS 460?

December 27, 2025 •

3 min read

The FDA considers INS 460, or microcrystalline cellulose, generally recognized as safe (GRAS), but like many dietary fibers, consuming it in large quantities can sometimes lead to minor side effects in some individuals.

Quick Summary

Bulking agent INS 460 (microcrystalline cellulose) is generally safe, but excessive intake may cause mild gastrointestinal issues like bloating, gas, or diarrhea in some individuals.

Key Points

Gastrointestinal Distress: High consumption of INS 460 can cause mild digestive issues such as bloating, gas, and abdominal cramps.
Bowel Changes: Due to its high fiber content, excessive amounts can lead to a laxative effect or, conversely, constipation if hydration is insufficient.
Nutrient Absorption: Very large, long-term intake might interfere with the absorption of certain nutrients, including fat-soluble vitamins and minerals.
Allergic Reactions: Though rare, some individuals may experience allergic symptoms such as skin rashes, itching, or swelling from microcrystalline cellulose.
Safety for Most People: When consumed at normal dietary levels, regulatory bodies consider INS 460 safe for most individuals, with side effects primarily linked to overconsumption.
Special Populations: Infants, children, and people with conditions like IBS should be cautious and may need professional medical advice regarding intake.

What is Bulking Agent INS 460?

Bulking agent INS 460 is the international designation for microcrystalline cellulose (MCC), a purified and refined form of cellulose derived from wood pulp or fibrous plant material. It is a naturally occurring, non-toxic, and indigestible dietary fiber. In food and pharmaceutical manufacturing, it serves multiple functions:

Bulking agent: It increases the volume and weight of products without adding calories, making it a popular ingredient in reduced-calorie foods and dietary supplements.
Binder: It helps bind ingredients together in tablet formulations, ensuring pills have a consistent shape and size.
Anti-caking agent: It absorbs moisture, which prevents powdered products like cheese and spices from clumping.
Emulsifier and Stabilizer: It helps maintain the texture and consistency of sauces, dairy products, and other processed foods.

Gastrointestinal Side Effects

Since INS 460 is an insoluble fiber, the most common side effects are related to the digestive system, particularly when consumed in large quantities. The severity of these effects varies from person to person.

Bloating and Gas

One of the most frequently reported side effects is gastrointestinal discomfort, including bloating and gas. This occurs because the indigestible fiber ferments in the large intestine, a process that produces gas. For individuals with sensitive digestive systems, this fermentation can be particularly noticeable.

Diarrhea or Constipation

As a fiber, INS 460 adds bulk to stool and can either lead to a laxative effect or, in some cases, constipation. The specific effect depends on the individual's hydration levels and other dietary factors. Sufficient water intake is crucial when consuming high-fiber products to help it pass smoothly through the digestive tract.

Potential for Nutrient Absorption Interference

While INS 460 is not absorbed by the body, an extremely high intake could theoretically interfere with the absorption of certain nutrients. Studies on various cellulose derivatives, though not always specific to INS 460, suggest that large amounts could impact the absorption efficiency of minerals and fat-soluble vitamins. This is more of a concern with long-term, high-dose consumption rather than typical dietary levels.

Rare Allergic Reactions

Although INS 460 is generally considered non-allergenic, a small number of sensitive individuals may experience an allergic reaction. These reactions are rare and could present with symptoms such as:

Skin irritation or rash
Itching or hives
Swelling of the throat or mouth
In severe cases, respiratory issues like difficulty breathing If any of these symptoms occur after consuming a product containing INS 460, it is advisable to discontinue use and seek medical advice.

Insights from Scientific Reviews

Regulatory bodies like the European Food Safety Authority (EFSA) have reviewed the safety of celluloses, including INS 460. Their conclusions support its safety at normal usage levels and do not set an Acceptable Daily Intake (ADI) limit. However, some studies, particularly those focusing on other cellulose additives like E466, have raised concerns about the potential for gut microbiome disruption and inflammation, and these findings are sometimes extrapolated to related celluloses due to similar properties. More specific research is needed to fully understand the long-term impacts on the gut for all cellulose additives.

Comparison of INS 460 with other Cellulose Additives


Feature	INS 460 (Microcrystalline Cellulose)	INS 466 (Sodium Carboxymethyl Cellulose)
Function	Bulking agent, binder, anti-caking agent	Thickener, stabilizer, emulsifier
Solubility	Insoluble fiber	Water-soluble
Main Risks (High Intake)	GI issues (bloating, gas), potential nutrient malabsorption	Gut microbiota disruption, inflammation, GI discomfort
Uses	Tablets, supplements, low-fat foods, grated cheese	Soups, dressings, processed cheese, processed meats
Regulatory Status	GRAS (FDA), No ADI (EFSA)	Approved food additive (EFSA)

Conclusion: Safe in Moderation

Bulking agent INS 460 is a widely used and generally safe food additive that serves several useful functions in food and pharmaceuticals. For the vast majority of people, its consumption at normal levels poses no significant health risks. However, as with any fiber, excessive intake can cause mild gastrointestinal issues like bloating, gas, or a laxative effect. People with pre-existing digestive conditions, pregnant individuals, or those with rare allergies should exercise caution and consult a healthcare professional. Overall, awareness and moderation are key to avoiding the minor, dose-related side effects of INS 460.

Re‐evaluation of celluloses E 460(i), E 460(ii), E 461, E 462, E 463, E 464, E 465, E 466, E 468 and E 469 as food additives

Frequently Asked Questions

Yes, INS 460, or microcrystalline cellulose, is generally recognized as safe (GRAS) by the FDA and approved by EFSA for use at typical dietary levels. Side effects are almost always associated with excessive intake.

INS 460 is the international food additive number for microcrystalline cellulose (INS 460(i)) and powdered cellulose (INS 460(ii)), which are both refined forms of natural plant cellulose.

Yes, in high doses, INS 460 can cause gastrointestinal discomfort, including bloating and gas. This is a normal reaction to consuming high levels of indigestible dietary fiber.

Allergic reactions to INS 460 are very rare. However, sensitive individuals may experience symptoms like rash or swelling. If you suspect an allergy, stop consumption and consult a doctor.

In extremely high doses, as with any fiber, INS 460 might reduce the absorption of some nutrients, particularly minerals and fat-soluble vitamins. This is not a concern at normal consumption levels.

While generally considered safe, pregnant women, as with all special populations, should consult a doctor before consuming products with high levels of INS 460.

INS 460 is microcrystalline or powdered cellulose, an insoluble fiber used as a bulking agent. INS 466 is sodium carboxymethyl cellulose, a water-soluble derivative used as a thickener and emulsifier, with different potential side effects related to gut health.