What vitamin deficiency causes itchy skin in dogs?

Itchy skin in dogs often gets brushed off as a minor annoyance, but it can signal underlying vitamin gaps. One common culprit is vitamin A deficiency—this nutrient keeps skin cells healthy and helps maintain the outer protective layer. Without enough, you might notice your dog scratching their belly or paws more, plus dry, flaky patches that worsen over time. Many commercial dog foods include vitamin A, but if you feed a homemade diet, double-check it meets AAFCO nutrient standards—local regulators often reference these guidelines for pet food safety.

Vitamin E is another key player for skin health; it acts as an antioxidant to fight inflammation that triggers itching. Dogs low in vitamin E might develop red, irritated skin, especially around the ears or armpits. If you’re considering supplements, always consult a vet first—overdosing on vitamin E can cause bleeding issues, and some regions require vets to approve certain pet supplements to comply with animal welfare laws. A quick check with your local animal control office can clarify any rules for your area.

B vitamins, especially biotin (vitamin B7) and niacin (vitamin B3), also keep skin and coat in top shape. A biotin deficiency might lead to scaly skin and dull fur, while low niacin can cause redness and constant scratching. Dogs on strict diets (like grain-free or limited-ingredient formulas) are more at risk, so make sure their food lists B vitamins on the label. Some cities have laws mandating pet food labels to list all nutrients clearly—if yours doesn’t, that’s a red flag to switch brands.

Omega-3 fatty acids aren’t vitamins, but they work closely with vitamins A and E to soothe itchy skin. A diet lacking omega-3s (found in fish oil or flaxseed) can make existing vitamin deficiencies worse, leading to more intense scratching. If you add fish oil to your dog’s food, start with small doses—too much can cause diarrhea. Also, remember to clean your dog’s bedding regularly; even with balanced nutrients, dirty bedding can irritate skin and mask deficiency symptoms.

If your dog’s itching persists after adjusting their diet, schedule a vet visit—other issues like allergies or parasites could be to blame. Always follow local laws when seeking pet care, such as ensuring your vet is licensed in your state or country. Keeping your dog’s diet balanced with essential vitamins isn’t just about stopping itching—it’s about supporting their overall health, so they stay active and happy for years to come.