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Ingredient file // Vitamin or mineral

Vitamin D3

Essential in small doses, risky in excess

Vitamin D3 is the form of vitamin D commonly added to dog food. Dogs need dietary vitamin D to absorb calcium and phosphorus and maintain bone. A complete food needs a controlled amount; extra D3 has no proven benefit for a healthy dog.

Role in the food Supporting nutrient
What it is
A concentrated form of vitamin D added to food because dogs depend on dietary vitamin D.
Made from
Usually a compound derived from sheep wool wax
Main job
Vitamin D for bone metabolism
Typical amount
Complete food target: 500 to 3,000 IU/kg dry matter
Watch for
Excess from faulty food or separate supplements
Not the same as
Vitamin D2

Straight answer

Is Vitamin D3 safe for dogs?

Read the adequacy statement, ignore D3 hype

Vitamin D3 near the end of an ingredient list is normal because food needs little of it. Look for a nutritional adequacy statement matching your dog's life stage. List position cannot tell you the dose. If the food is complete, do not add D3 without a medical reason.

Why it is in the food
Vitamin D for bone metabolism

Our read // In our catalog

In 1 of every 1 foods we track

Share of foods that list it

80%

2,559 of the 3,205 foods with an ingredient list on file, from 91 brands. 1,640 dry dog food, 763 wet dog food, 65 frozen dog food.

Each square is 1% of the catalog

Where it sits on the label

Median position 23. In the top five of 2 foods, so it is usually a minor ingredient.

Top five List position, heaviest first

Above the salt

9%

Usually listed after the salt, which caps it at roughly 1% of the recipe in 91% of foods.

Price per lb

Foods with it $3.12
All foods $3.25

Median of the cheapest bag price across 1,406 priced foods, 4% below the catalog. The price is the food's, not the ingredient's.

Who leans on it

7%

of the foods that list it are from Purina. 91 brands use it in total.

The story

Dogs helped reveal vitamin D, and recalls revealed its limits

Vitamin D was discovered partly through dog experiments. In 1914, Edward Mellanby was asked to find the cause of rickets, a disease of weak, deformed bones. He fed a group of dogs only oats and, without meaning to, kept them indoors away from sunlight. The dogs developed rickets. In 1919 he reported curing them by adding cod liver oil, and concluded the oil carried a dietary factor the oats lacked. Scientists later identified that factor as vitamin D.6,16

Herbivores and omnivores make vitamin D3 in skin exposed to ultraviolet light, and dogs were generally expected to do the same. A 1994 skin study found they cannot do it adequately and concluded that vitamin D3 is an essential vitamin for dogs. That is why the requirement sits in the diet: AAFCO's dog food profile gives vitamin D both a floor and a ceiling, so a complete food carries a measured dose.7,14

The ceiling matters because a food needs so little D3 that a plant error can push it far past the limit. In December 2018, FDA warned that several dry dog foods from a common contract manufacturer held as much as about 70 times the intended vitamin D. On January 31, 2019, Hill's Pet Nutrition began recalling canned dog foods after a dog developed vitamin D toxicity. The recall grew to 86 lots of 33 varieties before FDA closed it in December 2021.8,17

What it is

How it is made

Most commercial vitamin D3 starts as cholesterol from sheep wool wax. It is chemically turned into a precursor that ultraviolet light converts to D3. The vitamin then goes into a protective powder feed plants can blend evenly.9,10,13

  1. 01 // Source Sheep wool wax Lanolin supplies a precursor for the vitamin D3 made by the feed-grade supplier.
  2. 02 // Process Ultraviolet treatment Wool cholesterol is chemically turned into 7-dehydrocholesterol, then ultraviolet irradiation converts it into vitamin D3.
  3. 03 // Process Coated and dried Gelatin and starch protect the vitamin as the mixture becomes a free-flowing powder.
  4. 04 // Output Feed-grade D3 The powder goes into a vitamin premix so a small dose distributes through the food.

What is in it

Composition, as fed

1.3

% vitamin D3

Active vitamin in one tested feed-grade powder, rounded from its measured potency. Most of the powder is material used to carry and protect that small dose.

Vitamin D3 1.3%10
Carrier and other solids 94.3%10
Loss on drying 4.4%10

These are one supplier's as-sold batch results, not a universal recipe. Vitamin D3 and other solids are rounded calculations from the measured potency and loss on drying; carrier formulas vary.9,10,11

Benefits

What it does for your dog

Each benefit carries the same evidence grade as the claims below.

  1. 01

    Calcium and phosphorus absorbed from food

    The body turns vitamin D into calcitriol, the hormone that drives calcium and phosphate uptake in the gut. Dog skin makes too little vitamin D, so the diet is the real supply.6,14

    1. Strong
    2. Some
    3. Thin
    4. None
  2. 02

    No rickets in growing dogs

    Rickets is a failure of growing cartilage to mineralize. Mellanby produced it in dogs on a vitamin D poor diet and reversed it with cod liver oil. Nutritional rickets in young dogs is now considered rare.6,16

    1. Strong
    2. Some
    3. Thin
    4. None
  3. 03

    Normal growth plates at the right dose

    The benefit stops at adequacy. In a Great Dane puppy trial, very high dietary D3 disturbed growth plate development with no signs of poisoning, so more D3 does not mean stronger bones.7,15

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

Why it is in the bag

A required vitamin, added in a tiny dose

  1. Main nutrition
  2. Supporting nutrient
  3. Does a job
  4. Mostly filler

Dog skin makes too little vitamin D, so a complete food has to supply it, and AAFCO sets both a minimum and a maximum. Makers add D3 to land in that window, often through a vitamin premix. It sits near the end of the list because ingredients are ordered by weight and the dose is tiny. That small amount is meant to cover the dog's whole need for calcium and phosphorus control.6,7,9,14,18

  1. 01

    Supplies required vitamin D

    Dogs do not make enough vitamin D through sun exposure. Fortification gives a complete food a dependable source for calcium and phosphorus regulation.6,7

  2. 02

    Spreads a small dose

    A protective carrier turns concentrated D3 into a powder suited to premixing. That makes the small amount required easier to weigh and distribute through food.9,10

  3. 03

    Fortifies at low cost

    Cholecalciferol is inexpensive and widely available, and a formulated food needs little of it. The premix does the practical work of handling that small dose.2,7,9

How much AAFCO's dog food profile sets 500 to 3,000 IU of total vitamin D per kilogram of food on a dry matter basis.7

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.

  1. Brands say

    Vitamin D3 supports healthy bones

    Evidence

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

    Dogs depend on dietary vitamin D to manage calcium and phosphorus. AAFCO sets both a minimum and a maximum for complete dog food. This supports adequate D3, not an advantage from adding more.6,7

  2. Owners say

    Extra D3 eases itchy skin

    Outruns the evidence

    Evidence

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

    An 8-week crossover trial in 23 dogs with atopic dermatitis found lower itch and lesion scores with therapeutic cholecalciferol than with placebo. It did not test ordinary food fortification or healthy dogs.1

  3. Owners say

    Extra D3 fixes low blood vitamin D

    Outruns the evidence

    Evidence

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

    In a 28-dog gut disease trial, treatment raised blood vitamin D without improving clinical signs. In a separate 18-dog feeding trial, the D3 group's blood level did not rise. Response depends on the situation.2,5

  4. Brands say

    More D3 protects dogs from infection

    Outruns the evidence

    Evidence

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

    An industry-funded, 26-week study of 40 dogs raised circulating vitamin D with higher dietary doses. It did not measure infection or protection from disease, so its blood results do not support this claim.4

  5. Owners say

    D3 is the only useful vitamin D for dogs

    Outruns the evidence

    Evidence

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

    In a 3-month dietary trial of 61 adult dogs, a diet supplying D2 maintained total vitamin D measures and bone mineral content. The diets differed beyond vitamin D source, but D2 was not useless.3

The research

Studies worth knowing

Published research we read for this page, dog studies first.

  1. 1994 // Lab analysis of skin

    UV light raised vitamin D in rat skin, not dog skin14

    Skin samples from 5 dogs, compared with cat and rat skin

    Found. After ultraviolet B exposure, dog skin showed no significant change in vitamin D3, while rat skin rose 40-fold. Dog skin held about 1,858 ng/cm² of the vitamin D precursor, against 17,620 in rats.

    What it means. Sunshine will not cover your dog's vitamin D needs. The amount in the food is what your dog actually gets.

  2. 2003 // Feeding trial, 2 diets

    Very high D3 disturbed bone growth in Great Dane puppies15

    Growing Great Dane puppies, fed from 6 to 21 weeks of age

    Found. Puppies fed 1,350 µg of D3 per kg of diet, against 11.4 µg in controls, showed no signs of intoxication. Their main blood vitamin D marker rose 30 to 75 times, bone remodeling decreased and growth plates showed focal enlargement.

    What it means. Excess D3 harmed growing bone before any puppy looked sick. Do not add D3 to a complete puppy food.

Straight answers

What owners ask

  1. Q01

    Is it just filler?

    No

    Vitamin D is an essential nutrient, added in a small amount. The carrier in feed-grade powder helps manufacturers mix that dose evenly; it does not make D3 a bulk ingredient.6,9

  2. Q02

    Will sunshine replace it?

    No

    Dogs make too little vitamin D through their skin to meet their needs. A complete diet must supply it whether a dog spends most of its time indoors or outside.6

  3. Q03

    Should I add a supplement?

    Usually no

    A complete food already supplies vitamin D. The ingredient list does not reveal its total amount, so adding a separate product makes dosing uncertain. Use a supplement only for a specific medical reason.7,8,12

Who uses it

Brands, best sellers and the company it keeps

Top brands, by foods that list it

  1. Purina 179 / 186
  2. Blue 162 / 186
  3. Royal Canin 153 / 161
  4. Hill's 111 / 117
  5. Wellness 101 / 118
  6. Merrick 89 / 107
  7. Nulo 87 / 117
  8. NutriSource 85 / 91
  9. Instinct 76 / 98
  10. Nutro 68 / 71

Foods that list it / all the brand's recipes we track.

Plus 81 more brands.

Amazon best sellers that list it

  1. #1 Blue Life Protection Formula Adult Chicken and Brown Rice Recipe Dry Dog Food
  2. #2 Purina One SmartBlend Adult Dog Lamb & Rice Formula Dry Dog Food
  3. #3 Purina Pro Plan Adult Complete Essentials Shredded Blend Chicken & Rice Formula Dry Dog Food
  4. #4 Hill’s Science Diet Light Small & Mini Chicken Recipe Dry Dog Food
  5. #5 Blue Life Protection Formula Adult Small Breed Chicken and Brown Rice Recipe Dry Dog Food
  6. #6 Hill’s Science Diet Adult Sensitive Stomach & Skin Chicken Recipe Dry Dog Food
  7. #7 Stella & Chewy’s Marie’s Magical Dinner Dust Cage-Free Chicken Recipe Freeze-Dried Raw Dog Food Topper
  8. #8 Diamond Naturals Skin & Coat Formula All Life Stages Salmon & Potato Formula Dry Dog Food

Rank on Amazon's dog food best seller list, checked October 2026.

Usually listed with, share of the foods that list it

  1. Chicken 43%
  2. Mixed Tocopherols 38%
  3. Chicken Fat 35%
  4. Natural Flavor 34%
  5. Peas 29%
  6. Flaxseed 27%
  7. Chicken Meal 27%
  8. Brown Rice 23%
  9. Carrots 18%
  10. Dried Plain Beet Pulp 16%
  11. Sweet Potatoes 16%
  12. Beef 16%

On the shelf

Foods that list Vitamin D3

2,559 foods in our catalog list it. These 60 list it highest on the label.

Purina Beyond Mixers+ Immune Support Chicken Bone Broth Dog Food TopperPurinaPurina Beyond Mixers+ Immune Support Chicken Bone Broth Dog Food TopperTopper // No. 2 on the labelEvanger’s Super Premium Heritage Classic Chicken & Rice Dog Food TopperEvanger'sEvanger’s Super Premium Heritage Classic Chicken & Rice Dog Food TopperTopper // No. 5 on the labelWe Feed Raw Venison Recipe Frozen Dog FoodWe Feed RawWe Feed Raw Venison Recipe Frozen Dog FoodFrozen // No. 6 on the labelDave’s Pet Food Restricted Diet Sodium Wet Dog FoodDave's Pet FoodDave’s Pet Food Restricted Diet Sodium Wet Dog FoodWet // No. 6 on the labelEvanger’s Grain Free Braised Beef Chunks with Gravy - packed by hand! Wet Dog FoodEvanger'sEvanger’s Grain Free Braised Beef Chunks with Gravy - packed by hand! Wet Dog FoodWet // No. 6 on the labelTruDog Elevate Smoky BBQ Stew Grain Free Shredded Chicken Stew w/ Sweet Potat Wet Dog FoodTruDogTruDog Elevate Smoky BBQ Stew Grain Free Shredded Chicken Stew w/ Sweet Potat Wet Dog FoodWet // No. 7 on the labelBixbi Rawbble Grain-Free Freeze-Dried Dog FoodBIXBIBixbi Rawbble Grain-Free Freeze-Dried Dog FoodFreeze-Dried // No. 7 on the labelAgainst the Grain The Good Egg - Steak ‘n Egg Wet Dog FoodAgainst the GrainAgainst the Grain The Good Egg - Steak ‘n Egg Wet Dog FoodWet // No. 7 on the labelAgainst the Grain The Good Egg - Bacon N Eggs Scramble Wet Dog FoodAgainst the GrainAgainst the Grain The Good Egg - Bacon N Eggs Scramble Wet Dog FoodWet // No. 7 on the labelHalo Elevate Smoky BBQ Stew Grain Free Shredded Chicken Stew w/ Sweet Potat Wet Dog FoodHaloHalo Elevate Smoky BBQ Stew Grain Free Shredded Chicken Stew w/ Sweet Potat Wet Dog FoodWet // No. 7 on the labelZignature Inception Chicken Recipe Food Can Wet Dog FoodZignatureZignature Inception Chicken Recipe Food Can Wet Dog FoodWet // No. 7 on the labelZignature Inception Pork Recipe Food Can Wet Dog FoodZignatureZignature Inception Pork Recipe Food Can Wet Dog FoodWet // No. 8 on the label
Show 48 more
Evanger’s Heritage Classic Lamb & Rice Dinner Wet Dog FoodEvanger'sEvanger’s Heritage Classic Lamb & Rice Dinner Wet Dog FoodWet // No. 6 on the labelEvanger’s Roasted Chicken Drummet Dinner - packed by hand! Grain-Free Wet Dog FoodEvanger'sEvanger’s Roasted Chicken Drummet Dinner - packed by hand! Grain-Free Wet Dog FoodWet // No. 6 on the labelEvanger’s EVX Restricted Diet: Weight Management Wet Dog FoodEvanger'sEvanger’s EVX Restricted Diet: Weight Management Wet Dog FoodWet // No. 6 on the labelEvanger’s Heritage Classic Senior & Weight Management Wet Dog FoodEvanger'sEvanger’s Heritage Classic Senior & Weight Management Wet Dog FoodWet // No. 7 on the labelEvanger’s Super Premium EVX Restricted Diet: Skin & Coat Wet Dog FoodEvanger'sEvanger’s Super Premium EVX Restricted Diet: Skin & Coat Wet Dog FoodWet // No. 7 on the labelEvanger’s Chunky Chicken Casserole - packed by hand! Wet Dog FoodEvanger'sEvanger’s Chunky Chicken Casserole - packed by hand! Wet Dog FoodWet // No. 8 on the labelEvanger’s EVX Restricted Diet: Digestion Bland Diet Wet Dog FoodEvanger'sEvanger’s EVX Restricted Diet: Digestion Bland Diet Wet Dog FoodWet // No. 8 on the labelEvanger’s Grain Free; Super Premium Chicken Dinner Wet Dog FoodEvanger'sEvanger’s Grain Free; Super Premium Chicken Dinner Wet Dog FoodWet // No. 8 on the labelPurina Pro Plan Sport Adult High Protein Beef & Bison Entrée Classic Wet Dog FoodPurinaPurina Pro Plan Sport Adult High Protein Beef & Bison Entrée Classic Wet Dog FoodWet // No. 8 on the labelZignature Inception Pork Formula Dry Dog FoodZignatureZignature Inception Pork Formula Dry Dog FoodDry // No. 8 on the labelWysong Archetype Burgers Freeze-Dried Raw Dog FoodWysongWysong Archetype Burgers Freeze-Dried Raw Dog FoodFreeze-Dried // No. 8 on the labelWe Feed Raw Duck Recipe Frozen Dog FoodWe Feed RawWe Feed Raw Duck Recipe Frozen Dog FoodFrozen // No. 9 on the labelWe Feed Raw Beef Frozen Dog FoodWe Feed RawWe Feed Raw Beef Frozen Dog FoodFrozen // No. 9 on the labelWellness Core 95% Turkey & Spinach Grain-Free Wet Dog FoodWellnessWellness Core 95% Turkey & Spinach Grain-Free Wet Dog FoodWet // No. 9 on the labelWellness Core 95% Chicken & Broccoli Grain-Free Wet Dog FoodWellnessWellness Core 95% Chicken & Broccoli Grain-Free Wet Dog FoodWet // No. 9 on the labelEvanger’s Grain Free LID Venison + Beef Dinner Wet Dog FoodEvanger'sEvanger’s Grain Free LID Venison + Beef Dinner Wet Dog FoodWet // No. 9 on the labelZignature Essence LIR Landfowl Recipe Food Can Grain-Free Wet Dog FoodZignatureZignature Essence LIR Landfowl Recipe Food Can Grain-Free Wet Dog FoodWet // No. 9 on the labelThe Honest Kitchen Tender Turkey One Pot Stew Wet Dog FoodThe Honest KitchenThe Honest Kitchen Tender Turkey One Pot Stew Wet Dog FoodWet // No. 9 on the labelThe Honest Kitchen Slow Cooked Chicken One Pot Stew Wet Dog FoodThe Honest KitchenThe Honest Kitchen Slow Cooked Chicken One Pot Stew Wet Dog FoodWet // No. 9 on the labelInstinct Raw Boost RawBoost+ Mixers Tranquility Recipe Dog Food TopperInstinctInstinct Raw Boost RawBoost+ Mixers Tranquility Recipe Dog Food TopperTopper // No. 9 on the labelPurina Pro Plan Adult 7+ Senior Complete Essentials Chicken & Rice Entrée Classic Wet Dog FoodPurinaPurina Pro Plan Adult 7+ Senior Complete Essentials Chicken & Rice Entrée Classic Wet Dog FoodWet // No. 9 on the labelZignature Select Cuts Turkey Formula with Super Grains Dry Dog FoodZignatureZignature Select Cuts Turkey Formula with Super Grains Dry Dog FoodDry // No. 9 on the labelZignature Inception Fish Formula Dry Dog FoodZignatureZignature Inception Fish Formula Dry Dog FoodDry // No. 9 on the labelGather Free Acres Organic Free-Run Chicken Recipe for Adult Dogs Grain-Free Dry Dog FoodGatherGather Free Acres Organic Free-Run Chicken Recipe for Adult Dogs Grain-Free Dry Dog FoodDry // No. 9 on the labelPurina Beneful Chicken & Carrots Loaf Wet Dog FoodPurinaPurina Beneful Chicken & Carrots Loaf Wet Dog FoodWet // No. 10 on the labelWe Feed Raw Lamb Recipe Frozen Dog FoodWe Feed RawWe Feed Raw Lamb Recipe Frozen Dog FoodFrozen // No. 10 on the labelGrandma Lucy’s Macanna Pre-Mix Grain-Free Dog Food TopperGrandma Lucy'sGrandma Lucy’s Macanna Pre-Mix Grain-Free Dog Food TopperTopper // No. 10 on the labelDave’s Pet Food Bland Diet Pouches Dave’s Bland Duck & Pumpkin Pouch Recipe for Dogs / 10 Pack - Pou Wet Dog FoodDave's Pet FoodDave’s Pet Food Bland Diet Pouches Dave’s Bland Duck & Pumpkin Pouch Recipe for Dogs / 10 Pack - Pou Wet Dog FoodWet // No. 10 on the labelGravy Train Ground Dinner With Chicken Wet Dog FoodGravy TrainGravy Train Ground Dinner With Chicken Wet Dog FoodWet // No. 10 on the labelEvanger’s EVX Restricted Diet: Hip & Joint and Senior Support Grain-Free Wet Dog FoodEvanger'sEvanger’s EVX Restricted Diet: Hip & Joint and Senior Support Grain-Free Wet Dog FoodWet // No. 10 on the labelZignature Essence LIR Ranch Recipe Food Can Grain-Free Wet Dog FoodZignatureZignature Essence LIR Ranch Recipe Food Can Grain-Free Wet Dog FoodWet // No. 10 on the labelZignature Original Food Lamb Formula Grain-Free Wet Dog FoodZignatureZignature Original Food Lamb Formula Grain-Free Wet Dog FoodWet // No. 10 on the labelZignature Original Food Turkey Formula Grain-Free Wet Dog FoodZignatureZignature Original Food Turkey Formula Grain-Free Wet Dog FoodWet // No. 10 on the labelThe Honest Kitchen Roasted Beef One Pot Stew Wet Dog FoodThe Honest KitchenThe Honest Kitchen Roasted Beef One Pot Stew Wet Dog FoodWet // No. 10 on the labelPedigree Chopped Ground Dinner Adult Pouch, Chicken Wet Dog FoodPedigreePedigree Chopped Ground Dinner Adult Pouch, Chicken Wet Dog FoodWet // No. 10 on the labelPedigree High Protein Chopped Ground Dinner Can, Chicken & Duck Wet Dog FoodPedigreePedigree High Protein Chopped Ground Dinner Can, Chicken & Duck Wet Dog FoodWet // No. 10 on the labelPurina Beneful Freshly Prepared Stews Turkey Dinner with Spinach and Ditalini Pasta in Gravy Wet Dog FoodPurinaPurina Beneful Freshly Prepared Stews Turkey Dinner with Spinach and Ditalini Pasta in Gravy Wet Dog FoodWet // No. 10 on the labelPurina Beneful Freshly Prepared Stews Chicken Dinner with Carrots and Rice in Gravy Wet Dog FoodPurinaPurina Beneful Freshly Prepared Stews Chicken Dinner with Carrots and Rice in Gravy Wet Dog FoodWet // No. 10 on the labelBlue Wilderness Wild Meals Chicken & Sweet Potato Wet Dog FoodBlueBlue Wilderness Wild Meals Chicken & Sweet Potato Wet Dog FoodWet // No. 10 on the labelFirstMate Pacific Ocean Fish Weight Control Formula Grain-Free Dry Dog FoodFirstMateFirstMate Pacific Ocean Fish Weight Control Formula Grain-Free Dry Dog FoodDry // No. 10 on the labelFirstMate Pacific Ocean Fish Large Breed Formula Grain-Free Dry Dog FoodFirstMateFirstMate Pacific Ocean Fish Large Breed Formula Grain-Free Dry Dog FoodDry // No. 10 on the labelFirstMate Pacific Ocean Fish Meal Original Formula Grain-Free Dry Dog FoodFirstMateFirstMate Pacific Ocean Fish Meal Original Formula Grain-Free Dry Dog FoodDry // No. 10 on the labelZignature Essence LIR Landfowl Recipe Dry Dog FoodZignatureZignature Essence LIR Landfowl Recipe Dry Dog FoodDry // No. 10 on the labelZignature Inception Chicken Formula Dry Dog FoodZignatureZignature Inception Chicken Formula Dry Dog FoodDry // No. 10 on the labelZignature Original Turkey Formula with Probiotics Grain-Free Dry Dog FoodZignatureZignature Original Turkey Formula with Probiotics Grain-Free Dry Dog FoodDry // No. 10 on the labelZignature Original Small Bites Turkey Formula with Probiotics Grain-Free Dry Dog FoodZignatureZignature Original Small Bites Turkey Formula with Probiotics Grain-Free Dry Dog FoodDry // No. 10 on the labelRoyal Canin Veterinary Selected Protein PW Moderate Calorie Grain-Free Dry Dog FoodRoyal CaninRoyal Canin Veterinary Selected Protein PW Moderate Calorie Grain-Free Dry Dog FoodDry // No. 10 on the labelWellness Core Six Free-Range Lamb Grain-Free Dry Dog FoodWellnessWellness Core Six Free-Range Lamb Grain-Free Dry Dog FoodDry // No. 10 on the label

On labels as

Vitamin d3 supplement: what changes

One page covers every name. Here is what each label word adds, and whether it changes anything for your dog.

Vitamin d3 supplement

Matters for your dog No

Vitamin D3 Supplement

What it means AAFCO's guide to ingredient lists shows vitamin ingredients named either chemically or as the vitamin plus the word supplement, as in Vitamin B12 supplement. Here it marks an added vitamin source. We found no regulatory definition giving the word any extra meaning for dose or quality.

For your dog Nothing changes. It is the same added vitamin D3 under another label name, not an extra dose stacked on the food's vitamin D. A complete food still has to keep its total vitamin D between AAFCO's minimum and maximum.7,18

Sources

What we read

Checked October 1, 2026.

  1. 1 Vitamin D shows in vivo efficacy in a placebo-controlled, double-blinded, randomised clinical trial on canine atopic dermatitis Veterinary Record, 2018 // Journal
  2. 2 Treatment of Hypovitaminosis D With Cholecalciferol in Dogs With Protein-Losing Enteropathies: A Randomized, Double-Blind, Placebo-Controlled, Clinical Trial Journal of Veterinary Internal Medicine, 2025 // Journal
  3. 3 Efficacy of vitamin D2 in maintaining serum total vitamin D concentrations and bone mineralisation in adult dogs fed a plant-based (vegan) diet in a 3-month randomised trial British Journal of Nutrition, 2024 // Journal
  4. 4 Increased dietary vitamin D was associated with increased circulating vitamin D with no observable adverse effects in adult dogs Frontiers in Veterinary Science, 2023 // Journal
  5. 5 Rapid improvement in vitamin D status with dietary 25-hydroxycholecalciferol in vitamin D insufficient dogs Journal of Nutritional Science, 2021 // Journal
  6. 6 The Role of Vitamin D in Small Animal Bone Metabolism Metabolites, 2020 // Journal
  7. 7 AAFCO Dog Food Nutrient Profiles AAFCO, 2013 // Regulator
  8. 8 FDA Alerts Pet Owners about Potentially Toxic Levels of Vitamin D in Several Dry Pet Foods U.S. Food and Drug Administration, 2018 // Government
  9. 9 Vitamin D3 Feed Grade: Animal feed Corvay Specialty Chemicals, n.d. // Industry
  10. 10 Vitamin D3 500,000IU Feed Grade Arshine Group, n.d. // Industry
  11. 11 Vitamin D: Health Professional Fact Sheet National Institutes of Health Office of Dietary Supplements, n.d. // Government
  12. 12 Reading Labels AAFCO, n.d. // Regulator
  13. 13 Process for producing 7-dehydrocholesterol and vitamin D3 (US10329250B2) U.S. Patent and Trademark Office, via Google Patents, 2019 // Government
  14. 14 Dietary vitamin D dependence of cat and dog due to inadequate cutaneous synthesis of vitamin D General and Comparative Endocrinology (record via FAO AGRIS), 1994 // Journal
  15. 15 Dietary 135-fold cholecalciferol supplementation severely disturbs the endochondral ossification in growing dogs Domestic Animal Endocrinology, 2003 // Journal
  16. 16 Sir Edward Mellanby University of Sheffield, n.d. // University
  17. 17 FDA Alerts Pet Owners and Veterinarians About Potentially Toxic Levels of Vitamin D in 33 Varieties of Hill's Canned Dog Food in Expanded Recall U.S. Food and Drug Administration, 2019 // Regulator
  18. 18 What's in the Ingredients List? AAFCO, n.d. // Regulator
An ingredient on its own tells you very little. What matters is how much of it there is and where it sits in the list. That is why we weigh the top five rather than reacting to any single name further down. Back to the wiki

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