Food security

Double burden of malnutrition

Hunger gets a lot of attention internationally, but malnutrition and undernutrition are also serious problems with long-term effects. Susan Walker of the University of the West Indies explained matters to Sheila Mysorekar in an interview.
Girls in Jamaica. Sean Sprague/Lineair Girls in Jamaica.

What are the differences between hunger, undernutrition and malnutrition?

  • The term “hunger” is mostly used to describe short-term lack of food. It is about not being able to access or purchase sufficient food, and having to spend days without enough to eat. Hunger does not only affect developing countries, it can also be found in families living in poverty in high-income countries.
  • “Undernutrition” means that children do not grow as they should because they do not get sufficient food. We speak of “stunting” when children are short for their age, and “wasting” when their weight is too low for their height. Severe wasting can be treated in a hospital or in the community with ready-to-use therapeutic foods (RUTF). This type of undernutrition frequently occurs in famines and other crisis situations.
  • “Malnutrition” means bad nutrition, which does not only mean too little food, but also too much food or poor quality food. Therefore, overweight in children can also be considered to be a consequence of malnutrition.


Stunting is often considered an indicator of poverty.
Yes, and for good reason. It reflects the totality of a child’s physical existence, from pregnancy through early childhood. It is much more common than wasting and affects approximately one in four children under the age of five years in low and middle income countries. It is also a measure of inequality. Societies with greater levels of inequality have much bigger differences in the rates of stunting than societies with less inequality.

What are the common effects of ­undernutrition in children and what are the long-term consequences?
Undernutrition increases child mortality from infections, especially diarrhoea and respiratory infections. Severe acute malnutrition can also be a direct cause of death. Undernutrition does not only affect children’s physical development. Stunted children have lower levels of cognitive ability, and many show apathy and other behavioural impacts. Several long-term studies show that these effects continue through to adulthood with lower IQs, poorer levels of educational attainment and more frequent mental health problems. If women do not get sufficient food before and during pregnancy, their infants are more likely to be born with low weight and at increased risk of stunting, including the mental consequences.

What exactly are “micronutrient deficiencies”, and why are they important?
They are deficiencies of vitamins and minerals. Micronutrient deficiencies reflect the quality of the diet and can occur even where children have enough food, but of poor quality. The most important ones for young child health and development are vitamin A, iron, zinc and iodine. They are important for children’s ability to fight infections, for growth and for their ability to learn.

What are the most common causes of malnutrition and undernutrition?
Globally, the most common cause of undernutrition is inadequate feeding of infants and young children. This can be because of lack of food in the household. It is also caused by mothers not exclusively breastfeeding their infants in the first six months of life and by feeding infants and young children foods which do not provide them with enough energy and nutrients. Another important cause is infections like diarrhoea. In Jamaica, the main causes of undernutrition are poor infant and young child feeding. Infections are no longer as common.

A recent UNICEF report mentions a “1000-days-window” as a key to the problem of malnutrition. Why are those thousand days decisive?
They comprise the nine months of pregnancy and the first two years of life. This is the period when nutrition has the strongest influence on a child’s growth. The brain is also developing very rapidly during this period. We also know that early nutrition and growth can have long-term consequences for health such as higher risks of several chronic diseases in adulthood, for example hypertension and diabetes. These chronic diseases are spreading rapidly in low and middle-income countries. Many of these countries face what we call the “double burden of malnutrition”. They have increasing problems with obesity and related diseases, but at the same time, significant numbers of their children are affected by undernutrition.

What consequences does widespread undernutrition have for society?
Undernutrition in children leads to adults who are less well educated, earn less income and are less able to care for their own children. If a large share of children in a country is undernourished, this will affect national development. Women who were undernourished as children, more­over, are also more likely to have low-birth-weight babies.

What can be done?
Key interventions to promote good nutrition and growth are:

  • Promotion of exclusive breast-feeding in the first six months of life. This includes action to support mothers, including counselling and adequate maternity leave.
  • Promotion of better complementary feeding practices and greater dietary diversity. This can mean nutrition education for parents and, in the case of food-insecure households, the provision of additional food.
  • In Jamaica emphasis is placed on early detection of growth faltering when children attend health centres for routine visits. A child’s growth is monitored using growth charts, and if it is less than it should be, the mother can be counselled and asked to attend a special nutrition clinic where she will get further advice on what to feed her child and where supplementary foods can be provided if needed. This approach can reach children before growth retardation becomes severe, however it will work best in countries where there is good coverage with primary health centres and most children have access.


Is this about giving children simply more and better food, or what else is important?
It is important to see nutrition in context. There are important underlying factors, which influence nutrition. They include:

  • access to and availability of affordable food,
  • family care-giving practices,
  • women’s education and empowerment,
  • water supply and sanitation facilities as well as
  • access to health care and immunisations.

Nutrition is an important part of the early foundation children need, but children also need nurturing environments with opportunities to learn.

Please explain the multi-sectoral approach in the Home Visiting ­Stimulation Programme in Jamaica.
We trained community health workers to help mothers promote their child’s development. The health worker visits the home weekly or at least fortnightly and conducts a play session with the mother and child to demonstrate activities. She encourages the mother to talk more with her children and to continue the activities. We have shown that this programme has long-term benefits through to young adulthood in regard to education, mental health and income. Similar programmes have been implemented in Bangladesh and Colombia, and the government of Peru is currently making a major investment in early learning for young children.

Please comment on two programmes which UNICEF supports and mentions in its most recent report: SUN (Scaling Up Nutrition) and REACH (Renewed Efforts Against Child ­Hunger and Malnutrition).
These are important initiatives to increase not just nutrition programmes and interventions, but to address issues such as in-country capacity building, governance and coordination across sectors, which influence nutrition.


Susan Walker is professor of nutrition at the University of the West Indies’ Tropical Medicine Research Institute in Jamaica.
susan.walker@uwimona.edu.jm