Powdered Cellulose

Pulping separates cellulose from fibrous plants such as wood for paper and other products. Further processing turns purified pulp into a fine powder that pet food makers use as concentrated insoluble fiber.^1,6,7

1. 01 // Source Fibrous plants Wood is a common source, though suppliers also use other fibrous plant materials.
2. 02 // Process Made into pulp Pulping removes much of the lignin and other material surrounding the cellulose fibers.
3. 03 // Process Purified and broken down The cellulose is purified and mechanically broken into smaller fibers.
4. 04 // Output Powdered cellulose The dry fiber powder arrives at the pet food plant for mixing into a recipe.

1. 01

   Lowers available calories

   Cellulose replaces digestible material with fiber that dogs use poorly for energy. In a controlled wet food trial, the cellulose diet delivered less digestible energy than the control.²

2. 02

   Adds stool bulk

   Most of the insoluble fiber passes through the gut. Dogs fed cellulose produced more stool than dogs fed beet pulp in a kibble comparison.^1,5

3. 03

   Provides concentrated fiber

   The powder raises fiber without adding much protein. A dog food study describes cellulose as more expensive than several agricultural byproduct fibers, so low cost is not its advantage.^1,5

4. 04

   Supports weight control recipes

   Manufacturers use it to dilute calorie density. That changes how much energy a serving delivers, but the feeding plan still determines whether a dog loses weight.^1,2

How much A controlled kibble trial included cellulose at 10%; the wet food trial dosed powdered cellulose by body weight.^1,2

1. Brands say

   Cuts the calories available from a serving

   Evidence

   1. Strong
   2. Some
   3. Thin
   4. None

   Controlled dog trials agree on calorie dilution. In an 8-dog wet food trial, gross energy digestibility was 76.7% with powdered cellulose versus 84.4% without added fiber. That does not guarantee weight loss.^1,2

2. Brands say

   Firms loose stools

   Outruns the evidence

   Evidence

   1. Strong
   2. Some
   3. Thin
   4. None

   In a 12-dog kibble trial, cellulose produced firmer stools than beet pulp. A randomized trial in 19 dogs with acute diarrhea found no significant difference in recovery time. Cellulose is not a proven diarrhea treatment.^1,3

3. Brands say

   Keeps dogs full so they lose weight

   Outruns the evidence

   Evidence

   1. Strong
   2. Some
   3. Thin
   4. None

   A 16-dog study compared a diet with 8.5% cellulose against more fermentable fibers. The fermentable fiber dogs only tended to eat less by the end, a nonsignificant result. Nothing showed cellulose causing fullness or weight loss.⁴

4. Brands say

   Feeds beneficial gut bacteria like a prebiotic

   Outruns the evidence

   Evidence

   1. Strong
   2. Some
   3. Thin
   4. None

   One tested sample was 92.9% insoluble fiber. In the 19-dog diarrhea trial, added cellulose did not significantly change the measured intestinal microbiota. Calling it a prebiotic promises a benefit the dog data do not show.^3,5

5. Critics say

   It is just filler

   Outruns the evidence

   Evidence

   1. Strong
   2. Some
   3. Thin
   4. None

   The 8-dog trial measured lower energy digestibility with powdered cellulose, and the kibble trial measured a change in stool output. Those are functional effects. Cellulose supplies little protein, but it has a clear fiber job.^1,2,5