Malnutrition: How it hurts people, societies and the world

Updated Aug 16, 2021
Malnutrition impacts one in every three people globally. Forty-five per cent of all deaths in young children can be attributed to poor nutrition. Hunger isn’t the only issue. While 462 million of the world’s adults are underweight, nearly two billion are overweight.

Without good nutrition, neither people nor societies can reach their full potential. The cycle of poverty and inequality continues within families, communities and countries. Of those with chronic hunger, 60 per cent are women and girls.

Eliminating malnutrition is the most cost-effective way to address some of the world’s greatest challenges. Yet progress is insufficient to meet 2025 targets. The impact of malnutrition continues to be especially acute in fragile contexts and for those affected by violent conflict. Already, one in five deaths globally is associate with poor diet.
This article gives you the facts about malnutrition, its causes and effects. You’ll learn why COVID-19 has intensified nutrition challenges everywhere. And you’ll discover why 2021 is a critical point in the ongoing journey to nourish the world’s people. 
  1. What is malnutrition?
  2. What are the types of malnutrition?
  3. Who is most vulnerable to malnutrition?
  4. How extensive is malnutrition, globally?
  5. How is malnutrition diagnosed?
  6. What can be done to address malnutrition?
  7. What can be done to prevent malnutrition?
  8. How does malnutrition impact societies? 
  9. How is COVID-19 increasing malnutrition?

1. What is malnutrition?
Malnutrition is a condition that develops when there’s a deficiency, excess, or imbalance in a person’s nutrient intake. You may associate the condition with stories you see on the news during food crises in developing countries.

But the term can also apply to people who are overnourished. Malnutrition can occur when people ingest too much, eat the wrong things, don’t exercise enough or take too many supplements.

This article focuses on situations that occur when a person lacks the right food and essential nutrients. It’s the kind you might see in those news stories – and in the lives of millions of people who never make the news.

Here’s why this kind of malnutrition might occur:
  • a family is unable to grow, raise, or purchase enough diverse healthy food
  • adults aren’t aware of the importance of breastfeeding for babies, the healthiest foods for children, the right time to introduce foods or the healthiest amounts for age                                     
  • a region is impacted by factors such as civil conflict, natural or economic disaster
  • a child has an illness like diarrhea, which prevents their bodies from digesting, retaining and utilizing nutrients
  • a woman or girl suffers because of unequal or discriminatory feeding and care practices e.g. she is expected to eat last, least and poorer-quality food
A woman bends to tend her crops while holding her baby.
In Angola, Maria’s crops are struggling, and her son is severely malnourished. As of December 2020, an estimated 1.6 Angolans were facing food and nutrition insecurity due to climate shocks. Photo: Suzy Sainovsky

2. What are the types of malnutrition?
Malnutrition, or ‘undernutrition’ for our purposes, can manifest in several ways according to the World Health Organization:

I. Wasting or ‘thinness’ – a person’s weight is significantly low for their height
  • usually the result of acute, inadequate nutrition
  • the result of severe illnesses like diarrhea or during food shortage
​II. Stunting or ‘shortness’ – a person’s height or length is significantly low for their age
  • usually the result of long-term insufficient nutrient and energy intake
  • often coupled with frequent infections
  • is often found in situations of acute poverty, where pregnant and lactating women lack healthcare and proper nourishment or children are frequently ill
  • comes with life-long effects like diminished cognitive and physical development, poor health and a risk of degenerative diseases such as Diabetes 4
  • the number one risk factor for stunting in children under five years old is poor growth in the womb
III. Underweight – a person’s weight is severely low for their age
  • may present as stunting, wasting or both
  • usually the result of various conditions combined: extreme poverty combined with illnesses and prolonged lack of access to nutritious food
  • underweight is on the increase, due to impacts of the COVID-19 impact
  • globally, an estimated 39 billion in-school meals were missed in 2020 during school closures
IV. Micronutrient deficiencies – a person is lacking vitamins and/or minerals
  • iron deficiency and anemia in adolescents can causes reduced physical and mental capacity
  • lack of iodine can lead to mental impairment that reduces intellectual capacity
  • more than 2 billion people around the world suffer with micronutrient deficiencies
A five-year-old boy stands beside his father, who is squatting beside him.
In Rwanda, five-year-old Samuel (right, beside his father) was brought to a World Vision health clinic in 2007. Children who experience stunting as young children often experience challenges as adults. Photo: Jon Warren 

3. Who is most vulnerable to malnutrition?
“As an expert in nutrition, the more I learn about the consequences for vulnerable women, girls, and people of diverse gender identities, the more outraged I become.” 
               --Melani O’Leary, World Vision Canada
Young children, adolescents and women who are pregnant or breastfeeding are the most vulnerable to the malnutrition known as ‘undernutrition’. Here is why:
  • their bodies have a greater need for nutrients, such as vitamins and minerals
  • they are more susceptible to the harmful consequences of deficiencies e.g. adolescent girls are at high risk for iron deficiency anemia due to accelerated growth velocity and menstruation-related iron loss
  • poor nutrition during pregnancy can actually cause changes to the DNA of a mother’s growing children
  • once malnourished, babies and young children are the most vulnerable to contracting illnesses such as pneumonia or tuberculosis
  • children are at the highest risk of dying from starvation

Women and girls
Every day, women and girls experience malnutrition disproportionately. Sixty per cent of the world’s people with chronic hunger are female. Micronutrient deficiencies affect women and girls as a group, more than they do men and boys. Anemia is the leading cause of death for pregnant teenaged girls.

Women and girls often lack control over decisions affecting their health and nutrition. Girls forced into marriage may have little say as to whether they receive nutritious food and when they become pregnant. Whether in or out of marriage, adolescent pregnancy increases the risk for malnutrition and poor health – for both mother and baby.

A five-year-old boy stands beside his father, who is squatting beside him.
In India, this group of teen girls is learning the importance of taking iron supplements. Menstruation can deplete iron stores, leading to anemia. But, around the world, millions of girls and women don’t have enough iron-rich food. Photo: Neola D’Souza

4. How extensive is malnutrition, globally?
Malnutrition is one of the world’s greatest challenges. It affects people on all continents, of all ages. Here are some examples from the Global Nutrition Report:
  • one in every nine people is hungry, while one in every three is overweight or obese
  • an increasing number of countries is battling multiple forms of malnutrition, with high rates of both undernutrition and obesity
  • undernutrition explains about 45 per cent of deaths among children under five
  • overweight and poor diets elevate the risk of non-communicable diseases which in turn contribute to death and disability worldwide
  • health consequences of overweight and obesity contribute to more than seven per cent of all deaths
  • micronutrient deficiencies can negatively impact eyesight, bone growth and immunity
A woman lifts a baby, who is smiling. The woman is wearing a World Vision vest.
A World Vision team member greets a baby before he’s weighed and measured. He and his family are visiting a malnutrition screening centre in the world’s largest refugee camp – in Cox’s Bazar, Bangladesh. Photo: Jon Warren

5. How is malnutrition diagnosed?
This depends on factors such as a person’s age, where they live and the resources available through their country’s health system. Here’s a comparison between children’s screenings in North America and poorer or more fragile countries:

In North America
Babies and children are screened for malnutrition during regular checkups. Doctors regularly check their height (or length) and weight. If a child is significantly small or underweight compared with the average, the doctor might:
  • test for body composition e.g. skinfold thickness
  • perform blood tests
  • conduct a dietary analysis 

In developing countries or fragile regions
Children in developing countries often lack access to even the most basic healthcare. Regular check-ups, including thorough screenings for malnutrition, are out of reach for many.

Organizations like World Vision train community health workers and volunteers to screen people for malnutrition. It’s a way of extending healthcare beyond clinics and hospitals, which might be too far away for families to visit for regular weigh-ins.

World Vision supports screening for all forms of undernutrition by supporting:
  • regular growth monitoring
  • referring patients for more specialized care when needed
  • teaching parents and caregivers about nutrition
  • counselling them in ways to adjust children’s diets when needed 
  • screening for oedema (swelling under the skin) as a sign of malnutrition
  • empowering mothers to detect malnutrition in their children (measuring upper arm circumference)
A health worker measures the circumference of a baby’s left arm.
World Vision trains mothers to screen their children for malnutrition. A red measurement of the upper-arm circumference indicates Severe Acute Malnutrition. When this is the case, our health workers arrange for the child to receive treatment immediately. Photo: Stefanie Glinski

6. What can be done to address malnutrition? 
World Vision has made addressing malnutrition a top priority. Our goal is to ensure that mothers and children are well nourished across their global programming reach. We do this in many ways. Here are a few examples:
  • Emergency food – Drought, tsunamis, civil conflict. They’re all scenarios where families’ food sources can be devastated. World Vision is the World Food Programme's largest implementing partner, delivering food to people with the greatest need. We ensure culturally appropriate staples like grains and rice get to the most vulnerable people.
A boy kneels, to feed his sister some porridge with a spoon. They are siting on the ground.
In the Democratic Republic of Congo, World Vision provides nutritional porridge for supplemental feeding in regions where life has been torn apart by conflict. Photo: Jon Warren
  • Teaching and empowering mothers – In every community some families are still raising well-nourished children, despite poverty. World Vision works with the community to discover what these families are doing differently to keep their children healthy. Together, they develop interactive teaching sessions from this information, with the mothers explaining and demonstrating their methods.
A group of mothers feed their young children from bowls, sitting on the ground.
At this nutrition session in Uganda, mothers learn about sourcing, planning and preparing nutritious meals for their children from local ingredients. Photo: Jon Warren
  • Nutrition with many faces – World Vision combines the mother-led teaching sessions with a variety of other programs. These work together to improve children’s nutrition and overall health, either directly or indirectly. They include measures like:
    • increasing food production
    • improving access to education, including nutrition education
    • improving family income generation
    • promoting and supporting gender equity and family planning

When a child is in immediate danger
Even children with severe acute malnutrition can usually be treated in their own homes, with Ready-to-Use Therapeutic Foods. Those with medical complications or lack of appetite are referred to in-patient centres for more intensive treatment. These children might receive:
  • fluid management care
  • therapeutic feeding
  • antibiotics
  • Vitamin A supplementation
  • treatment for hypothermia or hypoglycemia
A mother holds a baby boy, who is smiling.
In Angola, baby Beto recovered from severe malnutrition after being treated at home with a ready-to-use therapeutic food. Read his story. Photo: Suzy Sainovsky

7. What can be done to prevent malnutrition?
“If breastfeeding did not already exist, someone who invented it today would deserve a dual Nobel Prize in medicine and economics.” – Keith Hansen, World Bank

In North America
Medical sites like The Cleveland Clinic highlight the critical importance of breastfeeding for mothers and babies alike. The Mayo Clinic offers information on good nutrition for children, pregnant women and senior citizens.

Given that North Americans are more likely to be overweight or obese than those in developing countries, Canada’s Food Guide offers suggestions like:
  • eating plenty of vegetables, fruits, proteins and whole grain foods
  • limiting highly processed foods
  • reducing sugar and sodium
  • cooking more often, avoiding takeout
  • reading food labels
A mother sits with a small girl on her lap. They are both smiling and eating from the same plate.
In India, parents learn the importance of combining different local ingredients together, to enhance the absorption of micronutrients like iron. Photo: Lipy Mary Rodrigues

In developing countries and fragile regions
According to UNICEF, here are top 10 ways to help prevent malnutrition in children:
  1. Breastfeeding within the first hour of life
  2. Breastfeeding exclusively for the first six months
  3. Solid food and mother’s milk after six months of age
  4. The right foods – in quality and quantity – fed frequently from six to 24 months
  5. Good hygiene and clean hands (to prevent illness like diarrhea)
  6. Iron, Vitamin A and deworming (to protect from diseases and anemia)
  7. Nutritious foods given frequently during and after illness
  8. Life-saving care and nutrition at the right time for severely undernourished children
  9. Improving the nutrition of adolescent girls
  10. Better nutrition, particularly during pregnancy and lactation

Fighting global malnutrition in 2021
In December 2020, the United Nations issued a year-long Nutrition for Growth (N4G) initiative, to support nutrition for the world’s children. It came as global concerns mounted about the impact of malnutrition as a result of the COVID-19 pandemic.  

World Vison has committed US$500 million in private funding to tackle malnutrition over the next five years, with another $700 million in grant-funded programs. This will protect more than 1 million children from malnutrition. Other aid agencies are also taking steps, as are governments and multilateral organizations like the World Bank.

How you can help
It may seem to you that big organizations have the problem well in hand. But each person can do something to help reduce malnutrition. Many initiatives succeed best when Canadians get involved. Here are some options:
  1. Donate gifts of life-saving nutrition 
Through the World Vision Gift Catalogue, you can help feed hungry children and families, restore severely malnourished children, ensure pregnant women receive critical prenatal vitamins or provide an ingenious way to help increase iron intake.
  1. Inform yourself about child malnutrition
The 1000 Day Journey is a World Vision-led initiative to keep children safe from malnutrition, in the womb, in their mothers’ arms and as they grow to be toddlers. Visit the World Vision site to learn more about why that window is so critical.
8. How does malnutrition impact societies?
Unchecked, malnutrition poses a very real threat to human progress. It holds back development: human, societal and global. That’s why we often refer to ‘the global burden of malnutrition’.

A boy sits at the kitchen table drinking from a mug.
In Ecuador, six-year-old Nicolás sits at the table to eat breakfast. World Vision's food distribution helped ward off severe malnutrition for many children in the area, during COVID-19 lockdowns. Photo: Chris Huber

Educational outcomes of malnutrition
Malnutrition limits a country’s intellectual potential. Undernourished children are more likely to suffer from intellectual impairments caused by nutritional deficiencies. They may struggle to learn or even concentrate and are more likely to drop out. This study, conducted in Ethiopia, found a strong link between malnutrition and poor academic performance.

Economic outcomes of malnutrition
Child or infant malnutrition can affect a person’s income for their entire lives. Here are some examples, from the International Journal of Epidemiology:
  • Undernutrition in childhood, primarily as measured by stunting, is consistently linked to worse economic outcomes as an adult
  • It’s not enough to simply increase a country’s GDP, if that increase in national income isn’t directed toward improving diets for children
  • Funds spent on childhood nutrition programs is money well spent, when it comes to improving long-term development within a country
On a national scale, for every dollar invested in nutrition in developing countries, $16 is returned to the local economy. But when malnutrition prevails, economies remain stagnant. Stunting can cost economies the equivalent of 10 per cent of GDP.

Equality outcomes of malnutrition
Malnutrition does not treat everyone equally. Nutrition and gender, for instance, are intimately connected. Globally, women and girls are more likely to eat last, least and food of lesser quality. Girls who are forced into marriage, or who become pregnant as adolescents outside of marriage, are more likely to suffer from malnutrition due to poverty.

While gender inequality can be a cause of malnutrition, it can also be a consequence. Malnourished girls and women can be trapped in a cycle of poverty and unmet potential, which lasts over generations. Because of gender inequality, women continue to lack control over the resources they need to meet their unique nutrition needs.

9. How is COVID-19 increasing malnutrition?
In 2020, the United Nations predicted the pandemic could result in dramatic increases in wasting (very low weight for height). Without swift action, women and girls will suffer some of the worst consequences.

We haven’t yet seen the full extent of pandemic’s impact on the world’s children. But we do have past examples, like the deadly Ebola outbreak in West Africa from 2013 to 2016. World Vision notes that such deadly viruses can:
  • reduce people’s access to nutritious foods, as families quarantine and supply chains break
  • rob families of ways to nourish their children, as they lose jobs or sources of income
  • reduce opportunities to screen for malnutrition, as health workers focus on the virus and nutrition clinics close down
A woman sits outside a house made of mud and sticks. Three children stand near her.
Contagious illnesses can increase malnutrition levels. During the 2014-2016 Ebola outbreak in Sierra Leone, malnutrition increased due to lack of access to food and medical screenings during quarantine. Photo: Sarah Wilson

In its Aftershocks report, World Vision noted that even when malnutrition screenings resumed after Ebola, only one-quarter of children could receive treatment. This led to stunting in thousands of girls and boys, plus a higher risk of contracting infectious disease.

From this example, World Vision calculated that COVID-19 could lead to an additional five million children suffering from malnutrition within 24 of the UN’s highest priority countries.