The F-75 diet is a specialized nutritional formula designed for the critical, initial phase of treating severe acute malnutrition (SAM) in hospitalized children. This low-protein, low-fat formula is crucial for safely restoring metabolic functions and correcting electrolyte imbalances before introducing a diet designed for rapid weight gain. Administered strictly under medical supervision, the F-75 diet is a foundational component of the World Health Organization's (WHO) internationally recognized protocol for managing severe malnutrition.
What is the F-75 Diet?
As defined by organizations like UNICEF and the WHO, the F-75 diet is a therapeutic milk formula characterized by its low concentration of energy, containing approximately 75 kcal per 100 ml. It comes in a powdered form that is reconstituted with water or as a ready-to-use liquid. The diet is specifically formulated to meet the physiological needs of a severely malnourished child during the stabilization period, which can last several days. During this fragile stage, a child’s compromised body systems cannot tolerate a high-protein, high-energy diet without risking serious complications, such as refeeding syndrome. The F-75 diet's composition is carefully balanced to provide essential nutrients without overwhelming the body's fragile metabolic state, prioritizing stabilization over immediate growth.
Key Components and Nutritional Profile
To achieve its unique purpose, the F-75 diet is formulated with a precise balance of macro- and micronutrients. The primary ingredients typically include milk powder, vegetable oil, maltodextrin (a carbohydrate source), sugar, and a specialized vitamin and mineral premix. This combination results in a low-protein, low-fat composition that is rich in carbohydrates and corrected for critical electrolyte deficiencies. The specific formulation is guided by research and WHO recommendations.
Essential nutritional characteristics of the F-75 diet include:
- Energy Density: Approximately 75 kcal per 100 ml.
- Protein Content: A low percentage of total energy, designed to avoid stressing a compromised metabolism.
- Fat Content: Also a low percentage, carefully balanced to provide some energy.
- Carbohydrate Content: High in carbohydrates, providing a necessary energy source that is easier for a malnourished body to process.
- Vitamins and Minerals: Fortified with essential vitamins and minerals to correct common deficiencies found in severely malnourished children. This includes vital micronutrients like potassium and magnesium, which are critical for correcting electrolyte imbalances. Iron levels are kept very low during this phase.
- Osmolarity: Controlled to be low, which is important for children with diarrhea.
Specialized versions, such as low-lactose or lactose-free F-75, are also available for cases with persistent diarrhea.
The Purpose and Phases of F-75 Treatment
The F-75 diet serves a very specific purpose within the WHO's three-phase protocol for managing severe acute malnutrition:
- Phase 1: Stabilization. The F-75 diet is used exclusively during this initial, critical phase. The primary goals are to treat any life-threatening complications (e.g., shock, infection), correct severe electrolyte and metabolic disturbances, and provide gradual, small feeds to prevent refeeding syndrome. The low protein and low sodium content of F-75 is key here. This phase typically lasts 2 to 7 days.
- Phase 2: Rehabilitation. Once a child is stabilized and their appetite has returned, they are transitioned from F-75 to a higher-energy formula, such as F-100, or a ready-to-use therapeutic food (RUTF) like Plumpy'Nut®. The goal of this phase is rapid weight gain and catch-up growth.
The controlled transition from F-75 to a more calorie-dense food is essential for ensuring a safe recovery.
How the F-75 Diet Works
For a severely malnourished child, the body’s metabolic functions are severely compromised. Introducing food too quickly can lead to a potentially fatal condition known as refeeding syndrome, which involves severe shifts in fluids and electrolytes that can overwhelm the heart and other organ systems. The F-75 diet is designed to prevent this by providing nutrients in a controlled manner that allows the body's systems to gradually recover. The diet's low osmolality is particularly beneficial for children with diarrhea, helping to prevent worsening of the condition. The specific electrolyte composition is designed to correct mineral deficiencies (such as potassium and magnesium) that are common in SAM patients. This careful, cautious approach is what makes F-75 so effective in the initial stages of treatment.
Comparison: F-75 vs. F-100 Therapeutic Milk
To understand the F-75 diet fully, it is helpful to compare it with its successor in the malnutrition treatment protocol, the F-100 diet.
| Feature | F-75 Therapeutic Milk | F-100 Therapeutic Milk |
|---|---|---|
| Primary Purpose | Stabilization during initial phase (Phase 1) | Rehabilitation and catch-up growth (Phase 2) |
| Energy Density | Approx. 75 kcal/100ml | Approx. 100 kcal/100ml |
| Protein Content | Low (approx. 0.9 g/100ml) | Higher (approx. 2.9 g/100ml) |
| Fat Content | Low | Higher |
| Carbohydrate Content | High | Adjusted for rehabilitation |
| Iron Content | Very low | Iron is added in this phase |
| Sodium Content | Low | Standard for rehabilitation |
| Treatment Phase | Initial stabilization (2-7 days) | Second phase (appetite has returned) |
Medical Supervision and Risks
The F-75 diet is not a casual nutritional supplement but a critical medical treatment that requires trained health personnel and medical supervision. It must be used in a therapeutic feeding center or hospital setting and should never be distributed for unsupervised use by families. Medical professionals monitor the child closely for any signs of complications, including potential refeeding syndrome. The low iron content in F-75 is a deliberate safety measure during the stabilization phase, as iron can be toxic in severely malnourished patients with infections. As noted in recent studies, critically ill patients on the F-75 diet may also require additional thiamine supplementation due to high needs and low standard formula levels.
Proper Preparation and Administration
Proper and hygienic preparation of the F-75 formula is essential to avoid bacterial contamination and ensure the correct nutritional profile is delivered. Key steps involve using boiled and cooled water, measuring ingredients precisely, and mixing thoroughly. For very weak children, nasogastric feeding may be used, and the feed is often given in small, frequent amounts (e.g., every 2-3 hours). The importance of hygiene, especially in resource-limited settings, cannot be overstated. Detailed instructions are provided by humanitarian organizations like UNICEF and the WHO for safe preparation and administration.
Conclusion
The F-75 diet is a life-saving nutritional tool, meticulously designed for the initial stabilization of children suffering from severe acute malnutrition. It represents a careful, medically controlled approach that prioritizes metabolic recovery and safety over rapid weight gain. By correcting life-threatening metabolic and electrolyte abnormalities, the F-75 diet provides a critical first step, paving the way for a more aggressive rehabilitation phase with the F-100 diet or RUTF and ultimately, a full recovery. Its development and widespread use, guided by WHO protocols, underscore the importance of specialized nutritional science in global public health initiatives. For more information, please consult the guidelines from the World Health Organization on severe malnutrition management.
How It Differs from Normal Feeding Practices
It is vital to reiterate that the F-75 diet is not a standard infant formula or a general nutritional supplement. It is a medical intervention for a specific, severe condition. Its low energy and protein content are not suitable for healthy, well-nourished children. Its use is temporary, lasting only until the child is stable enough to move to the next stage of recovery. The cautious, low-volume feeding schedule and specific electrolyte composition are tailored to the unique physiological state of a severely malnourished patient, making it fundamentally different from normal feeding practices. Any use outside of a supervised, clinical setting for SAM is inappropriate and potentially dangerous.
Long-Term Impact and Legacy
The development and implementation of therapeutic formulas like F-75 and F-100, guided by rigorous research and collaboration between health organizations, have had a profound impact on combating child mortality from severe malnutrition. By standardizing treatment protocols, these formulas have enabled humanitarian and health organizations to effectively manage SAM in challenging environments worldwide. They have shifted treatment from being primarily hospital-based to a more community-based approach for less-complicated cases using RUTF, while reserving inpatient care for the most critical patients. This strategic use of different therapeutic foods has dramatically improved survival rates and continues to be a cornerstone of modern pediatric malnutrition therapy.
