Ingredient file // Fruit or vegetable
Watercress
A small green with unproven benefits
Watercress is a peppery leafy vegetable that some kibble recipes use in dried form. Its leaves contain nutrients, but no study shows that the undisclosed amount in dog food improves a dog's health. The plant itself can irritate a dog's stomach.
- What it is
- The edible leaves and tender shoots of watercress, dried and ground for use as a vegetable ingredient.
- Made from
- Watercress leaves and tender shoots
- Main job
- Minor vegetable addition
- Typical amount
- Not published
- Watch for
- Plant exposure can upset a dog's stomach
- Not the same as
- Garden cress
Our read // In our catalog
In 1 of every 865 foods we track
Share of foods that list it
0%
3 of the 2,595 foods with an ingredient list on file, from 3 brands. 2 dry dog food, 1 freeze-dried dog food.
Each square is 1% of the catalog
Where it sits on the label
Median position 16. In the top five of 0 foods, so it is usually a minor ingredient.
Above the salt
Almost always listed before the salt, so there is more of it than a pinch.
Price per lb
Median of the cheapest bag price across 2 priced foods, about level with the catalog. The price is the food's, not the ingredient's.
Who leans on it
33%
of the foods that list it are from Evanger's. 3 brands use it in total.
What it is
How it is made
Growers harvest watercress for fresh greens. A published food-processing study used leaves that missed fresh-market standards, washing and drying them into powder. That is a documented route, not a specification for every dog food supplier.3,7
- 01 // Source Harvested greens Growers cut tender watercress leaves and shoots for the fresh vegetable market.
- 02 // Process Washed In one published process, off-grade greens were washed and disinfected before drying.
- 03 // Process Dried and milled Researchers dried the greens with hot air, then milled the dry material into powder.
- 04 // Output Watercress powder The dry powder is suitable for storage; a commercial dog's food may use another supplier's process.
What is in it
Composition, dry matter
24-27
% protein
Measured in leaves at different growth stages. The figure describes the dry leaf, not watercress's contribution to a finished dog food.
Why it is in the bag
What the manufacturer gets
-
01
Adds a named green
A brand describes dried watercress as a nutrient source. Its name gives the recipe a recognizable vegetable, while the ingredient list does not reveal a useful nutrient contribution.1,9
-
02
Uses off-grade leaves
Researchers turned watercress rejected from the fresh market into a storable powder. This creates an outlet for a perishable crop; a dog food cost advantage has not been published.3
-
03
Offers peppery flavor
Watercress tastes peppery to people, and a brand describes it as a flavor enhancer. No dog test isolates its effect on how readily dogs eat the food.1,7,9
How much A study fed 16 dogs a commercial kibble listing dried watercress, but did not report how much the recipe contained.1
Our read // The claims
What the evidence supports
Strong: controlled studies in dogs agree. Some: small or mixed dog data. Thin: mechanism or lab work only. None: nothing, or the evidence points the other way.
-
Brands say
Watercress adds useful vitamins to kibble
Outruns the evidence
Evidence
- Strong
- Some
- Thin
- None
Raw watercress contains vitamin C and vitamin K. A 16-dog study listed dried watercress but gave no dose or measurement of its vitamin contribution. The ingredient's benefit in the finished food remains untested.1,8,9
-
Brands say
Watercress gives dogs antioxidant protection
Outruns the evidence
Evidence
- Strong
- Some
- Thin
- None
A review covered 7 human trials involving 302 people and measured antioxidant markers, while laboratory work tested watercress extracts. Neither measured protection in dogs eating kibble with an undisclosed amount of watercress.1,2,4,9
-
Brands say
Dried watercress makes kibble tastier
Outruns the evidence
Evidence
- Strong
- Some
- Thin
- None
A brand calls dried watercress a flavor enhancer because the leaf tastes peppery. It appeared in a complete food fed to 16 dogs, but that study did not test preference for watercress itself.1,7,9
Straight answers
What owners ask
-
Q01
Is it just filler?
Mostly garnishDry watercress leaves contain measurable protein and fiber, so they are real food. The studied kibble did not disclose its watercress amount. A small listing gives you no reason to expect a meaningful nutritional effect.1,2
-
Q02
Why is it low on the list?
Small additionIngredients are listed by weight. In the studied food, dried watercress appeared after the vitamin and mineral additions. Its low position supports reading it as a minor ingredient, though the exact amount was not published.1,5
-
Q03
Is watercress toxic to dogs?
Plant irritantASPCA lists the watercress plant as a gastrointestinal irritant associated with mild vomiting and diarrhea. That plant warning does not measure the risk from dried watercress in a complete kibble recipe.1,6
-
Q04
Should I add fresh watercress?
No needThe bag gains no proven benefit from a watercress topping. ASPCA warns that exposure to the plant can cause mild vomiting and diarrhea, so leave fresh watercress out if your goal is to improve this food.1,6
Who uses it
Brands, best sellers and the company it keeps
Top brands, by foods that list it
Usually listed with, share of the foods that list it
- Chicken 67%
- Chicken Meal 33%
- Brown Rice 33%
- Chicken Fat 33%
- Oatmeal 33%
- Dried Egg 33%
- Carrots 33%
- Celery 33%
- Parsley 33%
- Beef 33%
- Beef Organs 33%
- Beef Bone 33%
Our read // On the bag
Read past watercress to the main recipe
If watercress sits near the vitamin and mineral additions, treat it as a small vegetable addition. Judge the bag by its main ingredients and nutritional adequacy statement. The published dog study gives no evidence that its watercress supplies a useful vitamin dose, antioxidant protection or better flavor.
Sources
What we read
Checked October 1, 2026.
- 1 Commercial Extruded Plant-Based Diet Lowers Circulating Levels of Trimethylamine N-Oxide (TMAO) Precursors in Healthy Dogs: A Pilot Study
- 2 Physicochemical and antioxidant evaluation of watercress (Rorippa nasturtium aquaticum L.) leaf extracts
- 3 Impact of Processing Approach and Storage Time on Bioactive and Biological Properties of Rocket, Spinach and Watercress Byproducts
- 4 Evaluating the Anti-Oxidant and Anti-Inflammatory Properties of Watercress Supplementation at Short-Term Follow-Up: A Systematic Review of Randomized Controlled Trials
- 5 Animal Food Labeling and Pet Food Claims
- 6 Toxic and Non-toxic Plants: Nasturtium (Watercress)
- 7 How to Grow Watercress in Your Garden
- 8 Watercress
- 9 Dried Watercress in Dog Food