Lactoferrin: Chemical Composition, Indications, Mechanism of Action, Side Effects and Interactions

Milk contains several proteins and peptides of interest to human health that have been researched for decades.

Among these proteins, Lactoferrin has attracted considerable attention due to its involvement in immune response, antioxidant, and inflammatory activities and its ability to fight pathogenic microorganisms.

It is a protein part of the transferrin glycoprotein family together with serum transferrin, ovotransferrin, melanotransferrin, and the carbonic anhydrase inhibitor.

Higher levels of Lactoferrin were found in colostrum and mature milk.

Lactoferrin is also found in mammalian secretions and is released from neutrophil granules during inflammation.

Lactoferrin has also been found in most mucosal secretions, such as uterine fluid, vaginal discharge, seminal fluid, saliva, bile, pancreatic juice, small bowel secretions, runny nose, and tears.

The lactoferrin concentration in bovine milk is only 0.5% to 1.0%, while human breast milk can contain up to 15% lactoferrin.


Lactoferrin plays several critical roles in human biology.

First, Lactoferrin is believed to play a role in absorbing iron through the intestinal mucosa. It may be the primary or only source of iron for infants. The main biological function is the binding and transport of iron ions.

Second, Lactoferrin has antibacterial, antiviral, antiallergic, antifungal, anti-inflammatory, antiparasitic, catalytic, anticancer and radioprotective, antioxidant, and immunomodulatory functions and properties.

Chemical composition

Lactoferrin (also called lactotransferrin) was classified as a member of the transferrin family due to its 60% sequence identity with serum transferrin.

Lactoferrin is an 80 kDa glycoprotein composed of approximately 690 amino acid residues at the structural level.

The molecule folds into two lobes (N lobe residues 1-333 and C lobe residues 345-691 in human Lactoferrin) connected by a peptide forming a 3-turn alpha helix.

Each lobe of Lactoferrin divides into two domains and binds to a Fe 3+ ion.

From a chemical point of view, Lactoferrin can reversibly chelate two Fe 3+ ions per molecule. Lactoferrin can also bind to other metal ions (Cu, Zn, Mn) but lower affinities.


  • 250 mg capsules.


The main functions of Lactoferrin in the body include the binding and transport of iron. It also helps fight infections. Some people take lactoferrin supplements for antioxidant and anti-inflammatory benefits.

Lactoferrin is touted as a remedy for a wide range of health conditions, including:

Hepatitis C

There is some evidence that Lactoferrin can inhibit hepatitis C infection.

Lactoferrin can help increase levels of interleukin-18 (an immune system protein that plays a crucial role in fighting the hepatitis C virus).


It causes a decrease in the count of acne lesions, inflammatory lesions, degree of acne, amount of sebum, and a reduction in triacylglycerols (a type of oil) on the skin’s surface.


In one report, laboratory tests determined that Lactoferrin may work with the mineral hydroxyapatite to help stimulate the growth of bone-forming cells known as osteoblasts.

Through the use of a lactoferrin supplement enriched with ribonuclease, a substance that promotes the formation of new blood vessels.


Lactoferrin protects the body from pathogenic microorganisms, such as bacterial, viral, and fungal infections.

It possesses antiviral properties of Lactoferrin and inhibits the binding of viruses to the cells of the body, and the replication of the virus in cells and increases the immune function of the body.


Lactoferrin can help protect against Helicobacter pylori infection.

Other benefits

  • Stimulation of the immune system.
  • Prevention of damage related to aging.
  • Promotion of healthy bacteria in the gut.
  • Regulate iron metabolism.
  • Diarrhea.

Mechanism of action

Lactoferrin receptors are found on monocytes, lymphocytes, neutrophils, intestinal tissue, and certain bacteria.

The ability of lactoferrins to bind to iron may explain part of their antibacterial activity.

Iron is essential to support the growth of pathogenic bacteria. Lactoferrin can also inhibit the binding of bacteria to the intestinal wall.

The possible antiviral activity of supplemental Lactoferrin may be due to its inhibition of virus-cell fusion and viral entry into cells.

Lactoferrin is believed to promote the growth and differentiation of T lymphocytes. Lactoferrin appears to bind only to sites on T4 (helper) and T8 (suppressor) lymphocytes.

Lactoferrin also plays a role in regulating cytokines and lymphokines, such as tumor necrosis (TNF) -alpha and interleukin (IL) -6.

The possible antioxidant activity of Lactoferrin may also contribute to its immunomodulatory activity.

Antioxidants are receiving increasing attention as potential therapeutic agents in infections and other diseases.

Lactoferrin’s ability to bind iron contributes to its antioxidant properties and antibacterial action. Free iron is a contributor to the generation of free radicals.


One to two capsules daily.

Side effects

Lactoferrin is generally considered in typical amounts found in foods (such as cow’s milk).

Lactoferrin can cause several adverse effects, including fatigue and constipation, when taken in excessive doses.

The possible side effects that can occur in medicines that contain Lactoferrin.

  • Diarrhea.
  • Acne.
  • Loss of appetite
  • Fatigue.
  • A cold.
  • Shaking chills.
  • Constipation .

This is not a complete list; on the other hand, these side effects are possible, but they do not always occur.

Some of the side effects can be rare but serious. However, consult your doctor if you notice any following side effects, especially if they do not disappear.

Warnings and Contraindications

Some people may have a hypersensitivity or allergy to Lactoferrin, which is contraindicated. In general, it is recommended that pregnant women and nursing mothers avoid using Lactoferrin because it has not been tested under these conditions.

If you experience drowsiness, dizziness, hypotension, or headaches as side effects when using Lactoferrin, operating heavy machinery may not be safe.

A vehicle should not be driven if the use of the drug causes drowsiness, dizziness, or dramatically lowers blood pressure.

Patients are also advised not to drink alcohol with the drug, as alcohol intensifies the side effects of drowsiness.


Some in vitro studies suggest that Lactoferrin works synergistically with antifungal agents, making them more potent.