Biotin

Feed biotin is manufactured rather than recovered from a food leftover. Producers synthesize and purify the vitamin, then dilute it with carriers so a small addition distributes evenly through a batch.³

1. 01 // Source Chemical precursor Manufacturers start with dibenzylbiotin, a compound used to synthesize the active form of the vitamin.
2. 02 // Process Synthesized and purified Chemical processing produces purified D-biotin as a nearly dry crystalline powder.
3. 03 // Process Blended with carriers Suppliers mix the concentrated vitamin with carriers to make feed preparations containing 2% or 10% biotin.
4. 04 // Output Feed vitamin powder The preparation enters a vitamin premix that the food maker distributes through the recipe.

1. 01

   Normal use of fats and sugars

   Biotin is the cofactor for 4 carboxylase enzymes that handle fats, glucose and some amino acids. The support is its essential role; no dog trial shows extra intake adds anything.⁵

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

   Skin and coat without deficiency lesions

   Kittens kept short of biotin on raw egg white diets lost hair and developed scaly skin until biotin was given. The dog evidence is an uncontrolled series, so this rests mainly on cat data.^2,5,7

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

   Higher blood biotin from the diet

   In 64 healthy dogs, blood biotin rose as dietary vitamin levels went up over 122 days. Biotin in food reaches the dog, though coat condition did not change.¹

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

1. 01

   Supplies measured biotin

   Biotin works with enzymes that process fats, sugars and some amino acids. Adding a measured source lets the formulator account for it even when ingredient sources vary.⁵

2. 02

   Distributes a small addition

   Suppliers dilute purified biotin with carriers before it reaches the food mixer. A premix makes the small addition easier to spread through a batch.³

3. 03

   Uses routine feed supply

   Multiple suppliers sell purified biotin and diluted feed preparations. Food makers buy it through the same premix supply route used for other added vitamins.³

How much A usual inclusion rate in dog food was not published; a skin treatment series gave about 5 mg per 10 kg of body weight daily.²

1. Brands say

   Biotin supports normal nutrient metabolism

   Evidence

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

   Biotin is a cofactor in 4 mammalian enzyme reactions. That supports its nutritional role, but the mechanism does not show that adding more improves a dog already eating a complete diet.⁵

2. Brands say

   Biotin treats dull coats and itchy skin

   Outruns the evidence

   Evidence

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

   In a Roche-authored series, clinicians recorded improvement in 108 of 119 dogs with skin or coat problems after biotin treatment. There was no untreated group, so the series cannot separate biotin's effect from other changes.²

3. Brands say

   Extra biotin makes healthy coats shinier

   Outruns the evidence

   Evidence

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

   A study assigned 64 healthy dogs to graded vitamin intakes and checked them through day 122. Blood biotin rose, but coat condition did not improve. Several vitamins changed together, so the study cannot isolate biotin.¹

4. Owners say

   Biotin in dog food is dangerous

   Outruns the evidence

   Evidence

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

   A feed safety assessment found biotin safe for animals under its authorized conditions of use. That addresses normal feed additions, not whether a dog should receive a large supplement without a reason.³

1. 2007 // Feeding trial, 4 vitamin levels

   More dietary vitamins raised blood biotin but not coat quality¹

   64 healthy privately owned dogs aged 1 to 8 years

   Found. Dogs were split into 4 groups with graded vitamin intakes and followed for 122 days. Blood biotin climbed with higher intake, yet coat and hair condition stayed the same. Several vitamins rose together, so biotin's share is unclear.

   What it means. Biotin in food does reach a dog's blood, but a healthy dog's coat should not look different on a higher dose.

2. 1989 // Treatment series, no comparison group

   Most dogs with coat problems improved on daily biotin²

   119 dogs with skin or coat problems such as dull coat, hair loss or itching

   Found. Dogs received about 5 mg biotin per 10 kg of body weight daily for 3 to 5 weeks. All signs were reported cured in 60% of cases and improved in a further 31%. Results differed by breed.

   What it means. This was a treatment dose without an untreated group, so it cannot show what the biotin listed on a bag does for a coat.

3. 1977 // Deficiency diet, then treatment

   Raw egg white diets stripped kittens' coats until biotin was given⁷

   Growing kittens (cat study; no comparable dog deficiency trial found)

   Found. Kittens fed 18.5% raw egg white for 25 weeks or 32% for 12 weeks developed hair loss and scaly skin and lost weight. A biotin dependent liver enzyme ran at 4% and 24% of its treated level. Biotin injections reversed the signs.

   What it means. Biotin deficiency is real and shows in the coat, but it took months of heavy raw egg white feeding to cause it.