What Is Donkey Milk? Does It Have a Role in Cancer Treatment?

Donkey milk has attracted attention in recent years both for its nutritional properties and for claims in alternative medicine . Historically, certain cultures used it for health and beauty; Cleopatra, for example, is said to have bathed in it daily as her beauty secret. Today, donkey milkis gaining popularity in European cosmetics and as a food supplement, particularly in countries such as Italy. Especially in our country, it is sold at high prices with claims that it benefits many diseases, including cancer, and marketed as a miraculous product. But do these claims have a scientific basis? Can donkey milk truly cure cancer, or is it a food with no role in cancer treatment? This article examines its nutritional value, health effects and possible cancer treatment role in light of current scientific data.

Nutritional Value and Properties of Donkey Milk

Donkey milk differs remarkably in composition from cow’s milk and even human breast milk. It is generally known as the milk closest in composition to breast milk . Nutritionally, it is low in protein and fat and high in lactose (milk sugar). The table below compares its main nutrients with human and cow’s milk:

Table 1: Comparison of donkey, human (breast) and cow’s milk composition.

According to these data, donkey milk’s protein content is much lower than cow’s milk (approximately %1.5 versus around %3), making it similar to breast milk. Fat content is also much lower than cow’s milk; donkey milk is almost fat-free (around %0.5–1). Conversely, its lactose content is high and close to breast milk. Low protein and salt (sodium, potassium) content reduces the kidney burden and allergenicity. Its low total protein and predominantly whey fractions (low casein, high whey) indeed make it similar to breast milk.

Beyond nutrition, donkey milk is rich in certain bioactive components , particularly the proteins lysozyme and lactoferrin . Known for antibacterial and immune-supporting properties, these proteins occur at much higher levels than in cow’s milk. Lysozyme, also present in human milk, naturally protects against microbes; donkey milk contains approximately 1 mg/mL (1000 µg/mL), while cow’s milk has trace amounts. Lactoferrin likewise contributes to bodily defenses and has antimicrobial effects, occurring at substantial levels. These components provide natural protection; high lysozyme content may even help donkey milk resist spoilage longer under appropriate conditions. One study reported lysozyme levels three times those in breast milk and almost none in cow’s milk, contributing to greater resistance to bacterial growth.

Donkey milk’s notable advantages include low allergenicity, high digestibility and immune-supporting components. In summary:

• Similarity to Breast Milk: Because of low protein (particularly casein) and a high whey proportion, it is considered the animal milk closest to breast milk . Infants and young children may therefore tolerate it more easily.

• Low Allergenicity: Its low total protein and different protein structure give it less allergy potential than cow’s milk. Children with cow’s milk allergy often tolerate donkey milk better.

• Antimicrobial Components: Its high levels of lysozyme and lactoferrin provide natural antibacterial properties. This may support immunity and make the milk more resistant to spoilage-causing bacteria.

• High Lactose: High lactose may improve nutrient use by increasing calcium and magnesium absorption. It may also support beneficial intestinal bacteria, producing a probiotic effect.

• Vitamin and Mineral Content: Donkey milk is particularly rich in B vitamins and vitamin C; its vitamin C content is close to human milk (approximately 57 mg/L, versus ~60 mg/L in human and ~27 mg/L in cow’s milk). Minerals such as calcium, phosphorus and magnesium may also support bone development.

However, donkey milk also has some disadvantages :

• Low Fat and Calorie Content: Its much lower fat content than cow’s milk means lower energy value. It may not provide sufficient energy alone, particularly for growing children or people with high calorie needs. An infant fed exclusively donkey milk was reported unable to grow normally and developed malnutrition.

• The Disadvantage of High Lactose: Although lactose benefits mineral absorption, lactose intolerance (sensitivity to milk sugar) in adults may cause digestive problems. Because donkey milk is lactose-rich, it may be unsuitable for lactose-intolerant individuals.

• Low Levels of Certain Nutrients: Donkey milk contains less of certain nutrients than cow’s milk. Calcium and some fat-soluble vitamins, for example, are higher in cow’s milk. Exclusively consuming donkey milk long-term may therefore cause inadequate intake.

• Cost and Accessibility: Donkeys yield very little milk (only ~1 liter daily on average). Limited production and rising demand make it very expensive, complicating regular consumption economically.

Does Donkey Milk Benefit Cancer?

A frequent question in alternative medicine is “Does donkey milk benefit cancer?”. A clear scientific answer is: No, there is currently no proven evidence that donkey milk treats or prevents cancer. Many consumers believe it will kill cancer cells or stop tumor growth. However, existing scientific literature does not confirm a direct therapeutic effect against cancer.

Faced with a serious disease such as cancer, people sometimes seek a “miracle food” . Donkey milk has recently become popular in this context. News and social media posts sometimes claim it can cure cancer, leading patients to place hope in natural products. However, scientifically evidence-based medicinerequires treatments with proven cancer efficacy (surgery, chemotherapy, radiotherapy, immunotherapy, etc.). Donkey milk studies have not yielded reliable evidence of tumor shrinkage or cure in cancer patients. Therefore, it is not possible to say that donkey milk has any role in cancer treatment.

As a nutritious food, donkey milk may be added to cancer patients’ diets (for example, for protein support or a different taste). However, remember that nutrition and treatment are different things. According to current knowledge, donkey milk is not a medicine destroying cancer cells in our body.

Scientific Studies and Evidence

Studies examining donkey milk and cancer are very limited. The few available studies generally involve laboratory cell cultures or animal experiments. Briefly reviewing their results:

• Laboratory (Cell Culture) Studies: In 2009, a Chinese laboratory study examined active donkey milk components in human lung cancer cells (A549 cell line), reporting inhibited proliferation and some cell killing. However, serious methodological shortcomings meant it was not considered reliable and did not appear in respected journals. Similarly, in 2014, a cell culture experiment at Uludağ University in Türkiye found powdered donkey milk killed approximately %50 of lung cancer cells through apoptosis at doses not harming healthy lung cells. Interesting though this was, researchers emphasized it was only the “initial stage” and specifically warned the public not to misinterpret the news and immediately start drinking donkey milk . This cellular result has no clinical meaning yet. The same team stated animal experiments would follow and a long research process was needed. Another laboratory study in 2020 produced different results: donkey milk and isolated casein and whey proteins were tested on human prostate cancer cells; no anticancer (tumor-killing) effect was found. Interestingly, casein from donkey milk increased cancer cell proliferation by %140. This shows components are not always beneficial and may sometimes cause undesirable effects.

• Animal Experiments: Very few donkey milk studies use animal models. Mouse experiments were planned as continuation of the Uludağ University project. A newer experimental study tested it in immunocompromised mice with aggressive breast cancer (4T1 triple-negative breast cancer). Treated mice showed significantly smaller tumors and less spread to organs such as liver and lungs than untreated mice. No deterioration in general health or weight loss was reported during treatment. These results suggest donkey milk components may slow tumor growth in animals.

• Immunological Effects: Some donkey milk proteins are proposed to have immune-mediated antitumor effects. Laboratory research found increased release of cytokines (such as IL-2, IFN-γ, TNF-α) that could strengthen immune responses around cancer cells. This suggests possible indirect anticancer activity; both direct cell-killing and immune-stimulating potential are considered. These mechanisms are undoubtedly promising but remain theoretical.

All these studies provide only preliminary scientific data. None of their results has been tested in humans or established through clinical trials. So far, no clinical trial (human experiment) of donkey milk exists. Whether laboratory or animal effects apply to humans remains uncertain. Many substances effective in laboratory cancer research were abandoned after failing in humans; donkey milk may be similar. Declaring it an effective cancer treatment based on a few positive results is therefore scientifically incorrect.

Uses of Donkey Milk

Although it has no proven cancer treatment role, donkey milk has potential uses elsewhere. Its main historical and current uses include:

• Nutrition and Allergy: Donkey milk is consumed as food for its nutritional content. In particular, allergy to cow’s milk protein (Cow’s Milk Allergy - İSA) in children has prompted interest in it as an alternative. Goat’s milk is often discouraged because it can cross-react, whereas mare’s and donkey milk have low allergenicity. Clinical observations show many children reacting to other milks tolerate donkey milk. For example, among 46 children with severe cow’s milk allergy, %82 successfully consumed it, with positive growth and development effects. It is therefore considered a valid alternative food for allergic children. However, infants under 1 year (particularly the first 6 months) should receive no animal milk; all milks, including donkey milk, should be tried only on medical advice when needed after age 1.

• Cosmetics and Skin Care: Donkey milk has a historical cosmetic and skin-health role. Cleopatra’s baths are the best-known example, but soaps, creams and lotions are now popular too. Lactic acid and vitamins are claimed to nourish and moisturize skin, while antioxidants reduce aging signs. European cosmetics increasingly use it. However, scientific evidence of concrete benefits is limited, relying more on traditional knowledge and marketing.

• Other Folk Remedies and Traditional Uses: Historically, donkey milk was used against various ailments. Some societies recommended it for respiratory diseases such as bronchitis and asthma or digestive problems such as ulcers and gastritis. Although its scientific basis is unclear, immune-supporting components (immunoglobulins, lactoferrin) were thought protective against infection. Traditional use to accelerate wound healing is also reported. Laboratory studies indeed show donkey milk and whey proteins may support wound healing by increasing cell migration.

• Functional Food and Supplements: Donkey milk is also considered a functional food. Research investigates adding it to probiotic yogurt and kefir to improve nutrition and health benefits. High lactose and growth-supporting factors may favor beneficial bacterial growth. In future, donkey milk powder or added milk may be incorporated into infant formula, elderly nutrition formulas or medical nutrition products. More research is needed before implementation.

Harms and Risks of Donkey Milk

Like every natural product, donkey milk consumption carries risks and points requiring care. “Natural” = “Harmless” is not always correct. Potential harms and risks include:

• Insufficient Scientific Evidence: No comprehensive long-term studies of human health effects exist. We therefore do not fully know possible harms alongside benefits. Lack of sufficient research does not mean a product is completely safe; rather, unknown risks may exist. For example, interactions with other cancer treatments and possible adverse effects during chemotherapy have not been studied.

• Infection Risk: Donkey milk is mostly sold raw (unpasteurized), increasing microbial contamination risk. Research shows potentially dangerous bacteria can grow in it. For example, the bacterium causing meningitis, sepsis and intestinal infection in infants, Cronobacter sakazakii (formerly Enterobacter sakazakii), has been isolated from donkey milk. Such pathogens may be fatal for newborns and immunocompromised people. Zoonotic agents such as brucella can also spread through unpasteurized milk. Pasteurized donkey milk is therefore recommended where possible; it should not be drunk raw.

• Allergy and Intolerance: Although less allergenic than cow’s milk, donkey milk is not completely nonallergenic. Rare allergic reactions to its proteins have been reported. High lactose may also cause bloating, gas and diarrhea in lactose-intolerant people, who should exercise caution.

• Delayed Treatment and Misinformation: A major risk is that products like donkey milk create expectations of miraculous treatment and disrupt actual care. Some people with cancer reject medical treatment for alternatives because of positive stories. This is extremely dangerous because it wastes valuable treatment time. Disease may progress and treatment prospects decline in a patient foregoing actual treatment because of donkey milk. Experts emphasize that such products must not replace treatment without scientific proof. High spending on donkey milk also creates financial losses for patients and families.

• Economic and Environmental Sustainability: Donkey milk production is expensive and limited. Ill people seeking a cure may face a substantial financial burden. High demand may encourage uncontrolled, unhygienic, unregulated production, creating public health risks.

In summary, donkey milk consumption requires the same rational caution as other foods. “It cannot hurt; what could happen?” should not lead to excessive consumption or hoping for treatment from it alone.

Conclusion and Its Role in Cancer Treatment

Donkey milk is an interesting food because of its nutrition and special components. An alternative food for children allergic to cow’s milk, it can also serve as a cosmetic and traditional ingredient and generally healthy drink. However, regarding cancer treatment, donkey milk has no proven effect or role. Scientific data have not shown it can cure cancer. Some promising laboratory findings exist, but whether they apply to humans remains uncertain.

Cancer treatment requires a multidisciplinary, evidence-based approach. Patients wishing to consume donkey milk or similar natural products as supportive food must consult their doctor. Drinking donkey milk must never replace chemotherapy or other cancer treatments. Beware of people and advertisements trading in hope and presenting it as “the only cure for cancer” .

In conclusion, donkey milk is a nutritious food, not a healing elixir. It has no proven benefit in cancer prevention or treatment. Future comprehensive research may identify components inspiring new therapies. Until then, scientifically based medical treatments remain our strongest weapon. Recognizing realistic benefits and limitations rather than viewing it as a miraculous cure is the best approach.

In light of this information, in a life-threatening disease such as cancer, it is essential not to embrace unscientific hopes or abandon current medical practice. Decisions about donkey milk based on scientific evidence and medical advice are the healthiest and safest path.