The Key Differences Between SAM and MAM Explained

October 27, 2025 •

3 min read

According to UNICEF, at least 13 million children under the age of five are affected by Severe Acute Malnutrition (SAM) globally. Understanding the distinction between SAM and Moderate Acute Malnutrition (MAM) is critical for effective diagnosis and treatment, as the severity and management protocols differ significantly.

Quick Summary

This guide details the core differences between Severe Acute Malnutrition (SAM) and Moderate Acute Malnutrition (MAM) in public health. It covers the distinct diagnostic criteria, severity levels, associated health risks, and required treatment approaches, clarifying these important classifications of childhood malnutrition.

Key Points

Severity is the Main Difference: SAM is the most severe and life-threatening form of acute malnutrition, while MAM is a moderate, but still serious, form of the condition.
Diagnostic Criteria are Distinct: WHO defines SAM and MAM using different anthropometric cutoffs, primarily based on weight-for-height z-score (WHZ) and mid-upper arm circumference (MUAC).
SAM Requires Intensive Treatment: Children with SAM, especially those with medical complications, need urgent, often inpatient, medical care using specialized therapeutic foods like RUTF.
MAM Can Be Managed in the Community: Treatment for MAM focuses on nutritional rehabilitation through supplementary feeding (like RUSF) and nutritional counseling, typically in an outpatient setting.
Preventing MAM Prevents SAM: Effectively treating MAM is crucial for preventing a child's condition from deteriorating into the more dangerous and intensive-to-treat SAM.
Acronyms Have Other Meanings: Outside of public health, SAM and MAM have different meanings. For example, SAM is a marketing term (Serviceable Addressable Market), and MAM is an IT term (Mobile Application Management).

What is Acute Malnutrition?

Acute malnutrition, often referred to as wasting, is a condition resulting from insufficient energy, protein, or other nutrients. It develops relatively quickly due to factors such as reduced food intake, low-quality diet, or illness. The World Health Organization (WHO) categorizes acute malnutrition into Severe Acute Malnutrition (SAM) and Moderate Acute Malnutrition (MAM). These classifications guide appropriate medical intervention, especially for vulnerable children under five.

Understanding Severe Acute Malnutrition (SAM)

SAM is the most severe and life-threatening form of acute malnutrition, characterized by extremely low weight-for-height and a high risk of death. Children with SAM have compromised immune systems and are highly susceptible to infectious diseases. This condition requires urgent medical attention.

Diagnosing SAM

Diagnosis for SAM uses WHO criteria based on anthropometric and clinical signs:

Extremely Low Weight-for-Height: Weight-for-height z-score (WHZ) less than -3 standard deviations.
Very Low Mid-Upper Arm Circumference (MUAC): MUAC less than 115 millimeters.
Bilateral Pitting Edema: Swelling in both lower limbs, indicating severe malnutrition.

Treatment for SAM

Treatment for SAM is intensive and follows WHO protocols. It can be inpatient or community-based and typically includes:

Stabilization of medical issues.
Specialized therapeutic foods like Ready-to-Use Therapeutic Food (RUTF).
Antibiotics for infection prevention/treatment.
Follow-up care.

Understanding Moderate Acute Malnutrition (MAM)

MAM is a moderate, yet serious, degree of acute malnutrition that can progress to SAM if untreated. It also increases susceptibility to illness. MAM treatment is often simpler and community-managed.

Diagnosing MAM

WHO criteria for MAM indicate less severe wasting:

Low Weight-for-Height: WHZ between -2 and -3 standard deviations.
Low Mid-Upper Arm Circumference (MUAC): MUAC between 115 mm and 125 mm.

Treatment for MAM

MAM management focuses on nutritional rehabilitation and preventing progression to SAM. It generally involves:

Supplementary Feeding: Nutrient-rich foods like Ready-to-Use Supplementary Food (RUSF).
Nutritional Counseling: Education on improved feeding.
Community Support: Integration with local programs.

SAM vs. MAM: A Comparison


Feature	Moderate Acute Malnutrition (MAM)	Severe Acute Malnutrition (SAM)
Severity	Less severe, moderate wasting.	Most severe, life-threatening wasting.
Diagnostic WHZ	Between -2 and -3 z-scores.	Less than -3 z-scores.
Diagnostic MUAC	Between 115mm and <125mm.	Less than 115mm.
Edema	Not typically present, or absent.	Presence of bilateral pitting edema.
Associated Risks	Increased risk of illness, potential progression to SAM.	High risk of death, severe medical complications, and infection.
Treatment Needs	Supplemental feeding, nutritional education.	Intensive, specialized medical care and therapeutic feeding.
Treatment Products	RUSF pastes (e.g., Nutrifeedo Lite).	RUTF pastes (e.g., therapeutic peanut butter).
Treatment Setting	Primarily community-based outpatient care.	Often requires initial inpatient care, followed by outpatient care.

Other Contexts for the Acronyms

SAM and MAM have different meanings outside of public health. In business, SAM stands for Serviceable Addressable Market. In IT, MAM can stand for Mobile Application Management. These uses are distinct from the nutritional definitions.

Conclusion

While both SAM and MAM are forms of acute malnutrition, their severity dictates different diagnosis and treatment. SAM is life-threatening requiring intensive care, while MAM is a moderate form manageable with supplementary feeding and education in the community. Accurate differentiation and appropriate intervention are crucial for improving outcomes for affected children. Addressing MAM is vital to prevent progression to SAM.

Frequently Asked Questions

In health, SAM stands for Severe Acute Malnutrition, a life-threatening form of wasting that is a leading cause of child mortality globally.

MAM stands for Moderate Acute Malnutrition. It represents a less severe, but still serious, form of malnutrition that can progress to SAM if not properly addressed.

Diagnosis is based on World Health Organization criteria using measurements like weight-for-height z-score (WHZ) and mid-upper arm circumference (MUAC). The presence of bilateral edema is also a sign of SAM.

SAM is significantly more dangerous. It is the most lethal form of malnutrition and is associated with a much higher risk of medical complications and death.

SAM requires intensive, often facility-based, therapeutic feeding with RUTF, while MAM can typically be treated with supplementary feeding (RUSF) and nutritional counseling in a community setting.

Yes, if left untreated or improperly managed, Moderate Acute Malnutrition (MAM) can deteriorate and become Severe Acute Malnutrition (SAM).

No, acute malnutrition (SAM and MAM) results from a recent and rapid reduction in nutrition, leading to wasting. Chronic malnutrition, known as stunting, develops over a longer period.

The acronyms have other meanings depending on the field. For example, SAM can mean 'Serviceable Addressable Market' in business, and MAM can mean 'Mobile Application Management' in IT.