Comparing Donkey Milk and Human Milk: A Nutritional Deep Dive
For thousands of years, donkey milk has been praised for its purported therapeutic and cosmetic benefits, with figures like Hippocrates and Cleopatra famously associated with its use. Its resurgence in modern times is largely due to the discovery of its surprising nutritional similarities to human breast milk, making it a promising alternative for infant feeding, especially for those with cow's milk protein allergy (CMPA). However, while the similarities are significant, crucial differences, particularly in fat content, must be addressed for proper nutritional use.
The Protein Puzzle: Similarities and Key Differences
One of the most striking parallels between human and donkey milk lies in their protein profile. Both are classified as "albumin milk" rather than "casein milk" like cow's milk, meaning they are rich in whey proteins and relatively low in casein. This creates a softer, more digestible curd in the stomach, which is beneficial for infants with sensitive digestive systems.
- Low Casein Content: Casein is the primary allergen in cow's milk. Donkey milk's low casein concentration makes it a hypoallergenic option for a high percentage of infants with CMPA. In fact, clinical studies have shown high tolerability rates (over 80%) in allergic children.
- Abundant Whey Proteins: Both milks have high levels of whey proteins like α-lactalbumin and lysozyme. Donkey milk, in particular, is noted for its exceptionally high lysozyme content, which is significantly more than in cow's milk and even higher than in human milk. Lysozyme is a powerful antimicrobial enzyme that offers protection against bacterial infections in the gut.
- Amino Acid Profile: The overall amino acid composition is quite similar between the two milk types, which is a key nutritional advantage for developing infants.
The Fat and Lactose Balance
While the protein similarities are compelling, a major difference exists in the fat and energy content. Donkey milk has a remarkably low fat percentage, often around 1.2%, which is significantly lower than human milk's 3.5%. Consequently, its caloric density is also about twice as low.
For infants relying exclusively on milk, this low fat content is a critical consideration. To be nutritionally adequate, particularly for pre-weaned infants, donkey milk must be fortified with a source of fat, such as vegetable oils, to provide the necessary energy for growth and development. Despite the low quantity, the quality of the fat is notable, with a favorable unsaturated to saturated fatty acid ratio and a higher proportion of polyunsaturated fatty acids (PUFAs) compared to other animal milks.
Lactose, the primary carbohydrate, is another point of convergence. The concentration of lactose in donkey milk is very similar to that of human milk. This provides a key energy source and contributes to the milk's sweet taste, which is often well-received by children. The high lactose content also facilitates the absorption of calcium, essential for bone development.
Beyond Macronutrients: Bioactive Compounds
Donkey milk contains a host of other beneficial compounds that are shared with human milk and contribute to its health-promoting properties.
- Immune Support: High levels of lysozyme and lactoferrin work together to provide potent antimicrobial and antiviral effects. This protective effect helps establish a healthy gut microbiota in infants and supports the immune system.
- Antioxidant Activity: Donkey milk is rich in vitamins C and E, and contains bioactive peptides with antioxidant properties. These compounds help combat oxidative stress and cellular damage.
- Anti-inflammatory Effects: Research, particularly in animal models, suggests that donkey milk may possess anti-inflammatory properties, which could be beneficial for conditions like inflammatory bowel disease.
Practical Considerations: Availability, Cost, and Safety
Despite its many benefits, several practical factors limit donkey milk's widespread use. The first is supply. Donkeys produce very little milk compared to cows, making it a specialty item that is often difficult and expensive to acquire.
Another safety concern, as with any raw milk product, is the risk of foodborne illness. While donkey milk has natural antimicrobial properties, it is essential that any milk intended for vulnerable populations like infants or the elderly be pasteurized to eliminate harmful pathogens. The transport of raw milk is often restricted by law, so finding pasteurized or powdered options is critical for safe consumption.
Nutritional Comparison: Donkey vs. Human vs. Cow Milk (per 100g)
| Component | Donkey Milk | Human Milk | Cow Milk |
|---|---|---|---|
| Protein | 1.5–1.8 g | 0.9–1.7 g | 2.9–3.7 g |
| Fat | 0.3–1.8 g | 3.5–4.0 g | 3.7–4.3 g |
| Lactose | 5.8–7.4 g | 6.3–7.0 g | 4.6–5.0 g |
| Ash | 0.3–0.5 g | 0.2–0.3 g | 0.70–0.72 g |
| Casein:Whey Ratio | ~40:60 | ~30:70 | ~80:20 |
| Lysozyme Content | High | High | Trace |
The Verdict: So, is donkey milk the closest to human milk?
Based on compositional analysis, donkey milk is indeed the most similar natural mammalian milk to human milk, particularly concerning its protein composition (low casein, high whey) and lactose content. However, calling it a perfect substitute is misleading due to its significant deficit in fat and calories, which must be addressed for infant nutrition. Its low allergenicity makes it a valuable alternative for children with CMPA, and its bioactive components offer distinct health benefits. The high cost, limited availability, and the critical need for pasteurization are important factors to consider before use. Ultimately, donkey milk is a fascinating and potentially beneficial dairy alternative, but it is not a direct replacement for human breast milk, which remains the optimal nutritional source for infants. For those seeking alternative feeding options, a consultation with a pediatrician is always recommended.
Learn more about the specific benefits and challenges of donkey milk from scientific reviews, such as this one covering its nutritional and therapeutic properties. [^1.6.4].
Final Conclusion
Donkey milk's chemical makeup closely mirrors human milk in several key ways, notably its high whey protein and lactose content. This similarity makes it an excellent hypoallergenic alternative, especially for infants with cow's milk protein allergies. However, it is not a perfect replica, as its low fat and calorie count necessitates fortification for infants. While offering unique bioactive compounds, its high cost and scarcity limit its widespread application, requiring careful consideration for those exploring it as a dietary supplement.
[^1.6.4]: Kaskous, S., & Pfaffl, M. W. (2021). Current Knowledge on Functionality and Potential Therapeutic Effects of Donkey Milk. Animals, 11(5), 1382. https://www.mdpi.com/2076-2615/11/5/1382
