What Is Lactoferrin?

Lactoferrin is a protein found naturally in the milk of humans, cows, and other mammals. It is also found in other bodily fluids like saliva, tears, mucus, and bile. Lactoferrin has antiviral and antibacterial properties, and helps the body transport and absorb iron.

In humans, the highest concentrations of lactoferrin can be found in colostrum, which is a very nutrient-dense first form of breastmilk produced soon after a baby is born. Babies can get plenty of lactoferrin from breastmilk, while food sources are available for adults.

Some people take lactoferrin supplements for their purported antioxidant and anti-inflammatory benefits. Though the lactoferrin used in supplements is typically sourced from genetically modified rice, it can also come from cow's milk.

This article will discuss the purported uses and benefits of lactoferrin, side effects, precautions, interactions, dosage, and food sources.

Purported Uses of Lactoferrin

Supplement use should be individualized and vetted by a healthcare professional, such as a registered dietitian, pharmacist, or healthcare provider. No supplement is intended to treat, cure, or prevent a disease.

Lactoferrin has a wide range of purported uses. As a supplement, it is thought to have antioxidant, antiviral, and antibacterial properties. Researchers are also starting to look at lactoferrin’s possible role in immunity with COVID-19 in mind.

Many believe that lactoferrin can support the immune system. However, most of the present research has been conducted in a lab rather than on humans and more evidence is needed in most cases.

The following is a look at available research on the purported uses of lactoferrin.

Infections

Lactoferrin may protect the body from harmful organisms that cause bacterial, viral, and fungal infections.

Bacterial Infections

It has been suggested that the binding action of lactoferrin to iron does not allow bacteria to use iron to transport through the body.

Though results are mixed, lactoferrin has been studied for its use in Helicobacter pylori (H. pylori) infection, a type of bacterial infection known to cause stomach ulcers. In one lab study, lactoferrin from cows was found to inhibit the growth of H. pylori. It also increased the strength of medications commonly used to treat the infection. However, this study was performed in vitro (in a test tube in a lab) and not in humans.

Other lab studies focusing on using lactoferrin for bacterial infections have found similar results, but more human trials should be conducted to confirm.

Viral Infections

Research has investigated lactoferrin's protective effects against viral infections, like the common cold, flu, herpes, and gastroenteritis. It's thought to do this by inhibiting viruses from attaching to cells and replicating. However, the research was based on nonhuman animals.

There's also some evidence that lactoferrin may inhibit hepatitis C infection. Several studies have investigated the relationship.

In one study, researchers discovered that lactoferrin helped increase levels of interleukin-18, a protein found to play a key role in fighting off hepatitis C. The year-long study involved 63 people with the virus, a small sample size. However, it should be noted that results regarding lactoferrin's role in hepatitis C prevention have been mixed.

Of particular interest is the potential ability of lactoferrin to prevent and treat COVID-19. Preliminary research on the subject has led researchers to believe lactoferrin could help manage both asymptomatic and mild-to-moderate COVID-19. However, the sample size in the study was small (92 people). Larger, longer-term studies are needed before recommending lactoferrin's use.

Fungal Infections

Lactoferrin is also thought to have anti-fungal activity.

Various animal studies have looked at whether lactoferrin may help treat fungal infections, including yeast infections, or candida. In one such study, yeast-infected mice treated with lactoferrin had less severe infections than mice not given lactoferrin.

More human trials are needed regarding lactoferrin's potential role in treating bacterial, viral, and fungal infections.

Acne

In one study, participants consumed either fermented milk with 200 milligrams (mg) of lactoferrin or fermented milk alone every day for 12 weeks. At the end of the treatment period, those given the lactoferrin-supplemented milk were found to have fewer acne lesions and less sebum (oil) compared with those who took the placebo.

Another small study found similar results. Adolescent participants with acne vulgaris took chewable lactoferrin supplements for eight weeks. By the end of the study, they had reduced acne lesions and inflammation. The supplements were also well-tolerated. However, the study did not include a control (comparison) group; therefore, the results are not as reliable as those of a control group study.

Osteoporosis

Although research on the bone-building benefits of lactoferrin is limited, preliminary research suggests that lactoferrin may aid in preventing osteoporosis.

In lab and mouse studies, lactoferrin has been found to stimulate osteoblasts, or the cells needed to build bones. It has also been found to alleviate osteoporosis symptoms, possibly through cell signaling. However, researchers aren't exactly sure how lactoferrin works to improve osteoporosis and if these benefits would translate to humans.

In another study, lactoferrin helped strengthen and preserve bones in mice whose ovaries had been removed. Removing the ovaries is said to control hormonal changes. These results led researchers to believe that lactoferrin could be useful in preventing and treating bone loss that occurs due to estrogen loss, a common occurrence in menopausal women. However, studies involving humans are lacking.

As with most purported uses of lactoferrin, more human trials are required regarding osteoporosis. While we can learn from animal and lab studies, results should be duplicated in humans to confirm the proposed benefits.

Other Uses

Other purported, but less-researched uses for lactoferrin include:

• Treating sepsis in preterm infants
• Supporting vaginal births
• Treating urinary tract infections
• Protecting against chlamydia
• Treating taste and smell changes from chemotherapy

More research is needed to support these claims. Be sure to talk with your healthcare provider if you are interested in using lactoferrin for these and other uses.

What Are the Side Effects of Lactoferrin?

Lactoferrin is considered safe in amounts typically found in food. In fact, lactoferrin is generally regarded as safe (GRAS) by the U.S. Food and Drug Administration (FDA).

Regardless, side effects are possible when using lactoferrin supplements.

Common Side Effects

Mild, common side effects can occur when taking lactoferrin. However, these are more likely when lactoferrin is taken in excessive doses.

Many studies on lactoferrin have reported no apparent side effects from taking it.

In one small, 30-day human trial, a few participants taking lactoferrin reported:

• Stomach pain
• Vomiting
• Constipation

In children, taking lactoferrin has been linked to reduced appetite.  

Severe Side Effects

Severe side effects have not been reported when taking lactoferrin.

However, it may be possible to be allergic to lactoferrin.

A study performed on mice found that administering lactoferrin into the blood or mucosal tissues could produce allergens. In the study, an allergic reaction causing airways to become inflamed was observed in the mice.

However, the same results have not been seen in humans. Stop using lactoferrin and seek immediate medical attention if you have an allergic reaction.

Precautions

There are few documented precautions when it comes to lactoferrin. Lactoferrin is generally recognized as safe, especially when consumed in recommended amounts.

It appears to be a safe supplement for many sensitive groups, like children and people who are pregnant.

Still, it's important to follow directions when using lactoferrin and not take more than directed. Taking more lactoferrin than recommended could result in side effects.

Dosage: How Much Lactoferrin Should I Take?

There is no standard dose for lactoferrin. This means dosage may depend on age, health conditions, and gender.

According to one review, in various clinical trials, lactoferrin has been used in doses of 100 mg (milligrams) to 4,500 mg per day. These doses did not result in any known toxicities.

Talk with your healthcare provider about finding the proper lactoferrin dose for your specific needs.

What Happens If I Take Too Much Lactoferrin?

Lactoferrin does not appear to have toxicities or the potential for overdose. Also, because lactoferrin is not a required nutrient for human life, there is no upper limit (UL).

If you take more lactoferrin than recommended, you may be more likely to experience side effects, like an upset stomach. Because of this, it's important only to take lactoferrin and other supplements as directed.

Interactions

Sometimes, supplements can interact with other supplements, medications, or nutrients. There are no known or well-documented interactions with lactoferrin.

However, even though there are no known interactions at this time, it is still important to talk with your healthcare provider before starting lactoferrin if you are taking any medications.

It is essential to carefully read any supplement's ingredient list and nutrition label to know which ingredients and how much of each ingredient is included. Please review this supplement label with your healthcare provider to discuss potential interactions with foods, other supplements, and medications.

How to Store Lactoferrin

You should take special care to store your lactoferrin supplements properly.

Lactoferrin supplements should be kept in a cool, dry place. Make sure your supplements are in an area not exposed to direct sunlight. Also, keep lactoferrin and other supplements out of reach of small children and pets.

Discard lactoferrin supplements once they reach the expiration date listed on the packaging.

Similar Supplements

Supplements that have similar purported benefits as lactoferrin include:

• Garlic: Various studies have found that garlic extract contains antibiotic properties.
• Vitamin D: The sunshine vitamin has more recently been found to potentially contain antiviral properties.
• Oregano oil: In lab studies, oregano oil has shown antifungal activity and potential usefulness in treating yeast infections.
• Vitamin A: Topical vitamin A (retinol) has long been touted as a useful supplement for acne.
• Boron: A trace element, some evidence suggests that boron can play a role in improving bone health, an important part of osteoporosis prevention.

Your healthcare provider can help you navigate various supplements, as it's sometimes recommended to take just one at a time for a health issue.

Sources of Lactoferrin & What to Look For

You can find lactoferrin in both food and supplement forms. As with any nutrient, a food-first approach is always best.

Lactoferrin supplements may only be necessary if recommended by your healthcare provider. Otherwise, you should be able to get all the lactoferrin your body needs from various foods.

Food Sources of Lactoferrin

Lactoferrin is present in the milk of mammals including humans, cows, and goats, among others. This means you'll find lactoferrin in various dairy products.

Foods made from the milk of cows or goats will contain lactoferrin. Lactoferrin-containing foods include dairy products like milk, cheese, yogurt, buttermilk, ice cream, butter, and cream cheese. Lactoferrin will still be present in lactose-free dairy products.

Breastfeeding infants and toddlers can obtain lactoferrin from breast milk.

Lactoferrin Supplements

Widely available for purchase online, lactoferrin supplements are primarily sold in capsule form. You can also buy lactoferrin in some natural foods stores, drugstores, and stores specializing in dietary supplements.

People following a vegan diet should check the supplement packaging to ensure the product will fit their diet. Capsule coatings are not always vegan.

It's important to mention that dietary supplements, including lactoferrin, are not as strictly regulated as medications are by the FDA. When choosing a supplement, it's best to look for products certified by ConsumerLabs, U.S. Pharmacopeia (USP), or NSF International. These organizations don't guarantee that a product is safe or effective. Still, they do test for quality as well as assurance that what is listed on the label is what is actually in the product itself.

Remember that no supplement will cure or prevent diseases, and nothing can replace a well-balanced and healthy diet.

Summary

Lactoferrin is a protein found in the milk of mammals like humans and cows. It has been studied for its potential antibacterial, antiviral, and anti-fungal properties. Some research shows that lactoferrin may also be used for acne, osteoporosis, and other health concerns. Lactoferrin is generally safe, but it is important to discuss it with your healthcare provider before using it.

Due to the limited research, it's too soon to recommend lactoferrin supplements as a treatment for any condition. If you're considering using it, talk to your healthcare provider first to weigh the potential risks and benefits and to discuss whether it's appropriate for you.