Urgent action needed to tackle malnutrition

Science can help design strategies to tackle malnutrition. The challenge is turning this knowledge into action.

Improving nutrition in the developing world has never been more important.

According to the Food and Agriculture Organization, more than a billion people — one sixth of the global population — have a diet so poor they may be severely underweight, have stunted growth, or lack the vitamins and minerals they need for good health (all are aspects of severe malnutrition, or undernutrition).

And as populations grow and local climates change, this number is sure to rise.

As a result, meeting the Millennium Development Goal of halving the proportion of people who suffer from hunger by 2015 seems increasingly unlikely.

Nutritional problems are not confined to the world’s poorest countries. Rapidly developing countries increasingly face a dual burden of undernutrition and ‘overnutrition’, as people adopt less nutritious (but calorie-rich) diets and less active lifestyles.

Scientists have frequently demonstrated that malnutrition — whether a lack of protein, micronutrient deficiencies or too much intake of fat — increases the risk of disease and death. Now there is growing evidence that poor nutrition in early life can also cause irreversible damage to brain development, adversely affecting an individual’s productivity in later life, translating into significant losses of earnings.

But the news is not all bad. Malnutrition in all its forms is entirely preventable. And our increased understanding of how malnutrition interacts with disease offers a wealth of information on how, and when, to tackle the problem most effectively. The challenge is to put this knowledge into effect.

A background article sizes up the burden of malnutrition, explaining its impacts on child and adult health and highlighting some of the options available to policymakers (see The challenge of improving nutrition: facts and figures).

In an accompanying opinion article, Harvard researchers Andrew Thorne-Lyman and Wafaie Fawzi argue we must concentrate on implementing scientifically proven interventions, like securing access to micronutrients, such as vitamin A or zinc, that play a key role in preventing and treating infectious disease (see Nutrition key to cutting infection rates).

Suresh Babu, from the International Food Policy Research Institute in Washington, reiterates the need for interventions such as food supplements, arguing they must be combined with social protection policies, such as food-for-work programmes, to safeguard the nutrition of vulnerable populations in times of economic crisis (see Nutritional security is in the balance).

Meanwhile, Jørgen Schlundt, director of the Department of Food Safety, Zoonoses and Foodborne Diseases at the WHO, suggests that nutrition could be significantly improved by tackling the problem of food safety in the developing world (see Food safety is critical to nutrition security).

Others make the case for using new scientific discoveries and technologies to inform nutritional interventions.

For example, Jim Kaput, from the US Food and Drug Administration, explains how the emerging field of nutrigenomics — which studies interactions between genes and nutrients — could potentially help to tailor nutritional policies for specific populations, so making them more effective. But he also warns that nutrigenomics is unlikely to deliver practical solutions any time soon (see Using genetics to tackle malnutrition).

Yet we urgently need to find solutions to malnutrition. Lewis Ziska, a plant physiologist at the United States Department of Agriculture, explains the worrying dual implications of climate change. More frequent droughts and floods will reduce food security, while rising atmospheric carbon dioxide will also make many staple crops less nutritious.

Ziska suggests that ‘biofortifying’ crops, i.e. increasing their nutritional value through genetic modification (GM), may be the only viable long-term solution to tackling these problems (see The ‘hidden hunger’ caused by climate change).

Indeed, GM advocates have promised an agricultural revolution, including even a complete meal in a plate of cassava. But, as Carol Campbell reports, it hasn’t yet materialised and, say analysts, the picture is a lot more complicated than flicking a few genetic switches (see Can GM crops feed the hungry?).

But they will have to accept that malnutrition’s effects will not be eliminated overnight. One reason is that its impact may be long-lasting. Some studies, for example, suggest that malnutrition before the age of two can cause adverse health and development effects that last up to three generations.

Another reason, however, is that there are no quick fixes. However effective nutritional interventions such as food aid or vitamin drops may be, they do not address the driving forces behind malnutrition, which often boil down to poverty — and the lack of education, healthcare, hygiene and sanitation that come with it.

Ultimately, the challenge of improving nutrition in the developing world is also one of reducing global poverty.

Sian Lewis,
Commissioning editor, SciDev.Net