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Limited evidenceImmunity

Transfer Factor

Colostrum-derived products sold as immune messengers, borrowing the name of a 1950s immunological concept. The original research concerned injected leukocyte extracts in specific immunodeficiencies, not capsules from cow colostrum.

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What the science says

  • The commercial product is not the studied substance Limited evidence

    A review examining the myths and facts around transfer factor concluded that the active molecules were never properly characterised and that modern commercial preparations lack controlled evidence for the general immune benefits claimed on their labels.

  • Historical clinical use was narrow and specialised Limited evidence

    Reviews of dialyzable leukocyte extracts describe use in specific conditions such as chronic mucocutaneous candidiasis and certain immunodeficiencies, given by injection under medical supervision. That literature does not support an oral colostrum supplement for everyday immunity.

  • No trials in healthy adults Limited evidence

    There is no randomized controlled trial showing that oral transfer factor supplements reduce the frequency or duration of common infections in healthy people.

Dosage & safety

Studied doseNo established dose. Labels typically suggest 200–600 mg of colostrum-derived powder daily.
SafetyDairy-derived, so unsuitable for people with milk allergy and possibly for those with severe lactose intolerance depending on processing. Composition varies unpredictably between brands. Avoid in autoimmune disease and during immunosuppressive therapy without medical advice; no data in pregnancy.

How to take it

TimingTiming does not matter.
With food?Either way.
Worth knowingThis is colostrum powder, so it is off the table with a milk allergy and may cause symptoms with severe lactose intolerance depending on processing.

Interactions

With medications

  • immunosuppressants and biologics for autoimmune disease

    Marketed as an immune modulator, so it may work against therapy that deliberately suppresses immunity. do not use it without your specialist's agreement

Well-established interactions only — this is not a complete list. Always tell your doctor and pharmacist what you take.

Frequently asked questions

Does transfer factor boost the immune system?

There is no randomized trial showing oral transfer factor supplements reduce common infections in healthy people, so the evidence is limited. The original research concerned injected leukocyte extracts in specific immunodeficiencies, not capsules made from cow colostrum.

What is transfer factor made from?

Commercial transfer factor supplements are colostrum-derived powders that borrow the name of a 1950s immunological concept. Reviews conclude the active molecules were never properly characterised, and composition varies unpredictably between brands.

Can I take transfer factor with a milk allergy?

No. Transfer factor is a dairy-derived colostrum powder, so it is unsuitable with a milk allergy and may cause symptoms with severe lactose intolerance depending on processing.

How much transfer factor should I take?

No dose of transfer factor has been established; labels typically suggest 200–600 mg of colostrum-derived powder daily. Do not use it with immunosuppressants or biologics for autoimmune disease without your specialist's agreement.

Scientific references

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