Updated November 2025
Malnutrition is a serious global health issue affecting millions of people, especially children. It happens when a person's diet doesn't provide the right balance of nutrients needed for healthy growth and development. Malnutrition can mean not getting enough food, not getting the right types of food, or even consuming too much of certain nutrients—and its effects can be life-threatening if left untreated.
In this guide, we'll explore the different types of malnutrition, common causes, where it's most prevalent, and what can be done to prevent and treat it.
Nurse Fartoun* measures Guled's* arm with a MUAC band to assess his level of malnutrition
What is Malnutrition?
Malnutrition occurs when someone's diet lacks the essential nutrients their body needs to function properly. This includes proteins, carbohydrates, fats, vitamins, and minerals. While many people associate malnutrition with hunger and food shortages, it can also result from eating an unbalanced diet—even when food is available.
Malnutrition encompasses both undernutrition (wasting, stunting, underweight) and overweight, obesity, and diet-related non-communicable diseases. In 2022, an estimated 149 million children under five were stunted, while 45 million suffered from wasting globally.
Types of Malnutrition
Malnutrition takes several forms, each with distinct causes and health impacts.
Undernutrition
Undernutrition happens when the body doesn't receive enough calories or nutrients. It includes:
Wasting: severe weight loss and muscle depletion, often caused by acute food shortages or illness
Stunting: impaired growth and development due to chronic undernutrition, leading to children being shorter than expected for their age
Underweight: low weight relative to age, indicating poor overall nutrition
Undernutrition is most common among young children and can have lasting effects on physical and cognitive development.
Micronutrient Deficiency
Also known as "hidden hunger," micronutrient deficiency occurs when the body lacks essential vitamins and minerals like iron, iodine, vitamin A, and zinc. Even if a child is eating enough calories, they may not be getting the nutrients needed for healthy growth. Globally, one in three children are not receiving the diverse, nutritious diets they need. Micronutrient deficiencies can weaken immune systems, impair vision, and slow brain development.
Overnutrition
Overnutrition results from consuming too many calories or an imbalanced diet high in fats, sugars, and processed foods. This can lead to overweight and obesity, which increase the risk of chronic diseases like diabetes and heart disease later in life.
While overnutrition is often associated with higher-income countries, it's increasingly affecting low- and middle-income countries as diets shift toward processed foods.
Symptoms of Malnutrition
The signs of malnutrition vary depending on its type and severity. Common symptoms include:
- Unexplained weight loss or failure to gain weight
- Fatigue and weakness
- Poor concentration and irritability
- Delayed wound healing
- Frequent infections due to weakened immunity
- In children: stunted growth, developmental delays, and difficulty learning
If you notice these symptoms in yourself or a child, it's important to seek medical advice promptly.
Lina* (9 months) is screened for malnutrition at an SC supported nutrition centre in Idlib
Causes of Malnutrition
Malnutrition doesn't have a single cause—it results from interconnected factors that prevent people from accessing or absorbing adequate nutrition.
Food Insecurity
Food insecurity means not having reliable access to sufficient, safe, and nutritious food. Around 673 million people worldwide faced hunger in 2024. Climate shocks, economic instability, and rising food prices make it harder for families to feed their children.
Poverty
Families living in poverty often struggle to afford nutritious food or pay for healthcare when children become ill. In the UK, 4.3 million children live in poverty. Globally, poverty remains a leading driver of malnutrition.
Conflict and Displacement
War and displacement disrupt food systems, destroy crops, and force families to flee their homes—often with little access to food or clean water. Conflict zones consistently report the highest rates of child malnutrition. In 2025, Save the Children worked in crisis-affected countries including Sudan, Gaza, and Somalia to deliver emergency nutrition support.
Poor Sanitation and Unsafe Drinking Water
Without access to clean water and proper sanitation, children are more vulnerable to diarrhoeal diseases that prevent their bodies from absorbing nutrients. In 2024, 1.7 billion people still lack safely managed sanitation services.
Limited Access to Healthcare
When children can't access healthcare, illnesses that cause malnutrition—like diarrhoea, malaria, and respiratory infections—go untreated. Early detection and treatment are crucial for preventing long-term damage.
Lack of Education
Parents who lack knowledge about nutrition and infant feeding practices may struggle to provide balanced diets for their children. Education programmes that teach caregivers about breastfeeding, meal planning, and hygiene can significantly improve child nutrition outcomes.
Child hunger: the scale of the crisis
37.7 million children were acutely malnourished in 2024, with 10.2 million severely malnourished
At least 18.2 million children were born into hunger in 2024 – about 35 children a minute
1 million child deaths a year are linked to severe malnutrition
45 million children under five are at risk of wasting – that's 7% of all children under 5
Improving breastfeeding rates could save over 820,000 children's lives each year
Where is Malnutrition Most Common?
Malnutrition affects every country, but the burden falls heaviest on sub-Saharan Africa and South Asia. According to UNICEF's 2024 Joint Child Malnutrition Estimates, globally, 42.8 million children under 5 suffered from wasting, with 14% of all stunted children live in South Asia.
Countries experiencing conflict, climate crises, or economic instability see particularly high rates of child malnutrition. In 2024, acute food crises in places like Somalia, South Sudan, and Afghanistan left millions of children at risk.
Effects of Malnutrition
The impact of malnutrition extends far beyond hunger. Malnourished children face:
Weakened immune systems: making them more susceptible to infections and disease
Cognitive impairments: affecting their ability to learn and reach their full potential
Stunted growth: with lasting physical effects into adulthood
Increased mortality risk: malnutrition contributes to nearly half of all deaths in children under five, according to the WHO
For communities, widespread malnutrition limits economic productivity and perpetuates cycles of poverty.
Treatment for Malnutrition
Treating malnutrition requires tailored approaches depending on its severity and underlying causes.
For children with moderate malnutrition, treatment often involves:
Therapeutic feeding programmes: providing high-calorie meals and nutritional supplements
Micronutrient supplementation: addressing deficiencies in iron, vitamin A, zinc, and iodine through fortified foods or supplements
Medical care: treating underlying illnesses like diarrhoea, malaria, or respiratory infections that worsen malnutrition
Breastfeeding support: promoting exclusive breastfeeding for the first six months of life, which provides optimal nutrition and protection against infection
For severe acute malnutrition, however, a breakthrough treatment has transformed how we save children's lives—ready-to-use therapeutic food.
Ereng, 18 months, loves eating the fortified peanut paste she has been given by Community Health Promoter Charles as part of her malnutrition treatment. Here she eats the whole packet in one go.
Fadumo, 30, is a S.A.M stopper. S.A.M stands for severe acute malnutrition. It is a deadly disease. Right now, in Somalia where she lives, S.A.M. threatens 386,000 children’s lives.
Ready-to-Use Therapeutic Food (RUTF): A Life-Saving Innovation
One of the most powerful tools in the fight against child malnutrition looks deceptively simple: a foil sachet of peanut paste.
Ready-to-use therapeutic food (RUTF) has revolutionised how we treat severe acute malnutrition. This nutrient-dense paste contains peanuts, milk powder, oil, sugar, and essential vitamins and minerals—everything a severely malnourished child needs to recover, packed into just three daily sachets.
What makes RUTF so effective is its practicality. It doesn't need water, cooking, or refrigeration, making it ideal for emergency settings and remote areas. Parents can give it to their children at home, avoiding the stress and cost of hospital stays. Children typically show visible improvement within days—regaining energy, resuming play, and rebuilding their strength.
Most children recover completely within six to eight weeks of treatment.
Save the Children has been at the forefront of RUTF distribution for over two decades. In 2024 alone, we delivered this life-saving treatment to malnourished children in some of the world's toughest places—from drought-stricken Somalia to conflict-affected Gaza. Our community health workers train caregivers to recognise malnutrition early and administer treatment, putting the power to save lives directly into families' hands.
The impact is extraordinary. Studies show that RUTF can achieve recovery rates of over 90% when combined with proper medical support—proof that even severe malnutrition can be reversed when children get the right help at the right time.
Learn more about the secret power of peanuts in our work.
Malnutrition Prevention
Preventing malnutrition requires long-term solutions that address its root causes:
Improving food security: supporting smallholder farmers, strengthening food systems, and ensuring families can afford nutritious food
Promoting breastfeeding and good nutrition: educating caregivers about infant feeding practices and balanced diets
Providing clean water and sanitation: reducing illness that prevents nutrient absorption
Strengthening healthcare systems: ensuring children receive timely treatment for infections
Empowering women: when mothers have education, resources, and decision-making power, children's nutrition improves
Governments, NGOs, and communities must work together to create environments where every child can access the nutrition they need.
How Save the Children is Fighting Malnutrition
Malnutrition is a preventable crisis, yet millions of children still face hunger every day. Save the Children is on the frontlines, delivering life-saving food, treatment, and long-term solutions to the communities that need them most.
In 2024, our nutrition programmes reached 20 million children worldwide, providing therapeutic feeding, RUTF treatment, and nutrition education to families. We work with local health workers to identify malnourished children early and give them the care they need to recover.
We're also tackling the root causes—improving access to clean water, supporting smallholder farmers, and advocating for policies that protect children's right to food. From emergency responses in crisis zones to community-led nutrition programmes, we're committed to ending child malnutrition for good.
Find out about our work tackling child hunger.
Common questions about malnutrition
What is the main cause of malnutrition?
Malnutrition results from multiple interconnected factors. The primary causes include food insecurity, poverty, conflict and displacement, poor sanitation, limited healthcare access, and lack of nutrition education. Often, several of these factors affect families simultaneously, making it difficult to access or absorb adequate nutrition.
How do you know if a child is malnourished?
Signs of malnutrition in children include unexplained weight loss or failure to gain weight, fatigue, irritability, frequent infections, stunted growth, and developmental delays. A healthcare professional can measure a child's weight, height, and mid-upper arm circumference to diagnose malnutrition and determine its severity.
Can malnutrition be cured?
Yes, malnutrition can be treated and reversed, especially when caught early. Treatment depends on the type and severity but may include therapeutic feeding programmes, ready-to-use therapeutic food (RUTF), micronutrient supplements, and medical care for underlying illnesses. Most children show significant improvement within weeks of proper treatment.
What is RUTF and how does it work?
Ready-to-use therapeutic food (RUTF) is a nutrient-dense peanut paste used to treat severe acute malnutrition. It contains peanuts, milk powder, oil, sugar, and essential vitamins and minerals. Children eat three sachets daily, and most recover within six to eight weeks. RUTF doesn't require water or cooking, making it perfect for emergency and home-based treatment.
Where is child malnutrition most common?
Child malnutrition is most prevalent in sub-Saharan Africa and South Asia. Countries experiencing conflict, climate crises, or economic instability typically have the highest malnutrition rates.
How can I help fight child malnutrition?
You can support organisations like Save the Children that deliver nutrition programmes, emergency food aid, and long-term solutions in affected communities. Advocating for policies that address poverty, food security, and climate change also makes a difference. Learn more about how you can help.
