Introducing New Foods as Part of an Elimination Diet Protocol

Reintroducing Foods & Building a Long-Term Balanced Diet

Following a successful elimination diet, the next phase is systematic food reintroduction. This process identifies which ingredients can be safely included in the dog’s long-term diet and which are likely to trigger adverse food reactions (AFRs), such as skin irritation, gastrointestinal issues, or ear infections.

When to Begin Reintroduction

Reintroduction should only begin when:

  • Clinical signs have improved or resolved during the elimination phase (typically after 8–12 weeks).

  • No other external factors (e.g., seasonal pollen, parasites, infection) are influencing the dog’s symptoms.

How to Reintroduce Foods

Introduce one new food at a time and monitor for signs of relapse. Each new ingredient should be fed for 7 to 14 daysbefore introducing the next.

Steps:

  1. Select a single ingredient not used in the elimination diet (e.g., beef muscle meat).

  2. Add the ingredient in isolation—ideally, without mixing it into the main diet—to assess tolerance.

  3. Monitor for reactions, including:

    • Increased itchiness or redness

    • Ear inflammation or discharge

    • Soft stools, gas, vomiting, or diarrhoea

    • Behavioural changes (restlessness, lethargy)

  4. Stop the new food if symptoms return. Wait for the dog to return to baseline on the elimination diet before trialing the next item.

  5. If no signs appear after 10–14 days, the food is likely tolerated and can be included in the long-term rotation.

Reintroduction Priority List

It’s advisable to first test nutrient-dense whole foods required for a balanced diet. Order will vary depending on the original elimination formula, but might include:

  1. Muscle meat from common proteins (e.g., beef, lamb, turkey, chicken)

  2. Organ meats (e.g., liver, kidney)

  3. Bone or calcium source (if not yet included)

  4. Whole fish or shellfish (e.g., sardines, mussels)

  5. Eggs

  6. Low-reactivity plant materials (e.g., pumpkin, zucchini, berries, leafy greens)

Avoid testing highly processed or multi-ingredient items (treats, biscuits, flavoured supplements) during this phase.

Tracking Responses

Keep a daily record of:

  • Skin and coat condition

  • Stool consistency and frequency

  • Any signs of pruritus, redness, or ear changes

  • Appetite and energy levels

Clear documentation is critical, especially when symptoms fluctuate or delayed reactions occur.


Building a Balanced Maintenance Diet

Once several ingredients have been reintroduced and tolerated, the diet must be expanded to ensure nutritional completeness. This includes:

  1. Rotate tolerated proteins to minimise sensitisation and provide a full amino acid profile.

  2. Include liver (as a source of vitamins A and B12, copper, and folate), and ideally kidney or spleen (source of selenium, zinc, and iron).

  3. Use appropriate raw meaty bones, eggshell powder, or calcium carbonate to achieve a balanced calcium-to-phosphorus ratio.

  4. If oily fish is tolerated, include sardines or mackerel. Otherwise, use an omega-3 supplement (e.g., marine algae oil) tailored to the individual’s tolerance.

  5. Consider seafood, kelp (if tolerated and appropriate), or a custom supplement to provide zinc, iodine, and selenium.

  6. Some dogs may tolerate certain vegetables or fruits (e.g., pumpkin, broccoli, blueberries) to support digestion, microbiome health, and antioxidant intake.

When to Use Supplements

If key ingredients remain excluded due to food reactions, a custom supplement plan may be needed to avoid nutrient deficiencies. This is especially critical for:

  • Calcium, if bones are not included

  • Vitamin D, if oily fish is excluded

  • Zinc and iodine, if seafood is not tolerated

  • Manganese, often low in animal-only diets

Support and Guidance

Reintroduction and maintenance planning should be done under the guidance of a veterinarian or certified nutritionist, particularly when:

  • The dog is a puppy, senior, or lactating female

  • The elimination diet was highly restrictive

  • The dog requires therapeutic support for a concurrent condition

Summary

Reintroduction is a critical phase in determining which foods trigger adverse responses and which can be included in a balanced maintenance diet. This phase must be approached systematically, with thorough documentation and professional oversight to ensure long-term health.

Jackie Gowland