Chapter 23: Combating Malnutrition Nuclear Techniques

This chapter was published on “Inuitech – Intuitech Technologies for Sustainability” on March 7, 2012.

 1.         A WORLD VIEW OF SUFFERANCE FROM MALNUTRITION:

Perhaps a simple medical definition for malnutrition is the condition that develops when the body does not get the right amount of the vitamins, minerals, and other nutrients it needs to maintain healthy tissues and organ function.   Unfortunately, malnutrition continues to be a noteworthy global problem, more specifically among children.  The main cause of malnutrition is hunger.  Hunger is most devastating when it attacks children, since it can affect their mental and physical development for the rest of their lives, thus deepening the poverty cycle since they have less access to education and opportunities for work later in life.  However, hunger also seriously affects adults, impeding their productivity and creating a host of associated health problems, making their lives even more difficult.  Furthermore, the terrible effects and legacy of HIV/AIDS are also tightly linked to hunger and malnutrition.

Malnutrition increases the risk of infection and infectious disease; for example, it is a major risk factor in the onset of active tuberculosis.  In communities or areas that lack access to safe drinking water, these additional health risks present a critical problem.  Lower energy and impaired function of the brain also represent the downward spiral of malnutrition, as victims are less able to perform the tasks they need to do in order to acquire food, earn an income, or gain an education.  Starvation is a form of malnutrition.  In some cases, malnutrition is very mild and causes no symptoms.  However, sometimes it can be so severe that the damage done to the body is permanent, even though they survive.

The World Health Organization (WHO) cites malnutrition as the greatest single threat to the world’s public health.  Improving nutrition is widely regarded as the most effective form of aid to humanity.

According to the 6th. Report on World Nutrition Situation, Progress in Nutrition, published by the Standing Committee on Nutrition, although the proportion of undernourished people declined between 1969 and 1971, the trend reversed between 2004 and 2006, and thereafter began to rise.  This trend continued through 2009 and shows that progress towards achieving the World Food Summit hunger reduction target and the first Millennium Development Goal (MDG) faltered prior to the recent food and financial crises.  Food and nutrition insecurity were on the rise before 2008.  Thus the impacts of the global downturn – soaring food prices, reduced remittance streams, contractions in trade, accelerated reductions in foreign direct investment and decreased official development assistance – on developing countries did not create the current situation, but rather significantly worsened an already existing problem.

The first Millennium Development Goal (MDG) calls for the eradication of extreme poverty and hunger by 2015, and its achievement is crucial for national progress and development.  One of the indicators used to assess progress towards MDG 1 is the prevalence of children less than 5 years old who are underweight for their age.  A second indicator is the prevalence of hunger in a population, that is, the proportion of the population whose dietary intake is below the minimum dietary energy requirement.

With an estimated increase of 105 million undernourished people in 2009 alone, the Food and Agriculture Organization (FAO) of the United Nations projects that approximately 925 million individuals were hungry in 2010.   Although this number is down from the 1.02 billion (1.017 millions rounded) estimates made during the aftermath of the food and financial crises, it remains shockingly high.  This means that almost one in six people are still not getting enough to eat on a daily basis.  The following table illustrates the progress around the world in each category: Slide1As shown in figure 22-01, the highest prevalence of undernourishment, one in three persons, is in sub-Saharan Africa. The greatest absolute number of undernourishment is in Asia and the Pacific (578 million), followed by sub-Saharan Africa (239 million), Latin America and the Caribbean (53 million) and the Near East and North Africa (37 million).

28 countries (19 of them in Africa) are moving in the right direction to achieve the hunger indicator for Millennium Development Goal 126, but current rates of progress are insufficient to meet the 2015 target. Eighteen countries, mostly in Africa, have levels of hunger that are worse than they were in 1990.

It is interesting to note that while the number of hungry people is decreasing everywhere in the world except in Latin America & the Caribbean, the number for developed countries has jumped from 15 million to 19 million which represents a 26.7 percent increase.

Here is the result of a comparative analysis of the progress that was made in 2010: Slide2The central role of nutrition to development is emphasized by the growing international awareness that the magnitude of malnutrition as a global health problem will prevent many countries from achieving the Millennium Development Goals.  The urgent need for effective nutritional interventions is clearly indicated by the current global situation where – on the one hand – 170 million children are underweight and undernutrition that is an important factor in more than half of all child deaths worldwide and – on the other hand – more than a billion adults are overweight.  “The double burden of malnutrition”, i.e., overlapping under and over nutrition, results in a very heavy burden on health systems in countries where treatment of diet-related non-communicable diseases will be increasingly needed at the same time as undernutrition is still prevalent.  In particular, infants and young children in resource poor settings are vulnerable to the devastating effects of undernutrition and poor health as demonstrated by the fact that 99 percent of all young children dying in 2001 (10.6 million) lived in low and middle income countries and poor nutrition contributed to 1 out of 2 deaths.

Deficiencies of vitamin A, zinc and iron are major public health concerns as they contribute to impaired growth and cognitive development during early life and to poor health in children.  These nutritional deficiencies are affecting the lives of billions of people in the developing countries.   Here is a brief description of each deficiency:

  1. Vitamin A Deficiency:  Vitamin A deficiency occurs when too little vitamin A is taken in and absorbed from food.  Vitamin A also comes from beta-carotene, a precursor found in fruits and vegetables, however, investigations have shown that beta-carotene is not as bioavailable as once thought, meaning that more must be eaten to get an adequate amount of vitamin A.  An estimated 250 million pre-school children in developing countries are effected by vitamin A deficiency, although sever deficiency that causes blindness is declining.

Vitamin A deficiency is an essential nutrient in the human diet, contributing to the functioning of the retina, the growth of bone, and the immune response.   Apart from preventable, irreversible blindness, vitamin A deficiency also causes reduced immune function, leading to an increased risk of sever infectious disease and anaemia.  It also increases the risk of death during pregnancy for the mother and foetus and after birth for the newborn.

It is worth mentioning that bioavailability refers to how much of a given substance is in a form that can be readily used by the body.  In nutrition, it is not only important to have enough of a particular nutrient but it must also be “available” to be used by the body.

2.      Zinc Deficiency:  Zinc deficiency is caused by low intake and/or low absorption of bioavailable zinc.  Diets low in meat and fish increase the risk of zinc deficiency, because zinc is poorly bioavailable in cereals.

Zinc is an essential nutrient.  It is an essential part of many enzymes (Protein molecule that catalyzes chemical reaction in the body) and plays an important role in protein synthesis and cell division.  The health consequences of zinc deficiency includes: Poor Immune System Function; Growth Retardation; and Delayed Sexual Maturity in Children.

3.      Iron Deficiency:  The most common reason for iron deficiency anaemia, especially among infants and children, is due to inadequate iron from food.  Parasites, infections, stomach and digestive diseases, and blood loss during menstruation may also worsen anaemia.  Iron deficiency is the most prevalent nutritional deficiency worldwide.  It is a major public health problem with adverse consequences particularly for women of reproductive age and for young children.

When there is not enough iron in the body, fewer red blood cells are produced.  This reduces the capacity of the blood to transport oxygen.  As a result, symptoms, ranging from fatigue and inability to concentrate, to impaired physical and cognitive development of children, can occur.  Iron deficiency anaemia may also cause problems during pregnancy particularly in developing countries, where it can increase the risk of premature delivery, as well as the risk of maternal and foetal complications, and death.

2.         NUCLEAR ISOTOPES:

The International Atomic Energy Agency (IAEA) recognized the fact that good nutrition is essential to health and quality of life.  IAEA is dedicated to helping Member States achieve their social and economic goals and working to address the problems underlying poor nutrition.  In fact, many Agency activities serve basic human needs, by applying nuclear science to increase food production, improve health care, improve management of water resources, and assess success of environmental pollution.

Nuclear science provides valuable tools for monitoring factors that influence nutrition, such as micronutrients, body composition, and breast milk uptake.  Through its sub-programs on nutrition, IAEA is helping countries apply these tools to their nutritional problems and is supporting leading-edge research on the interaction between nutrition and environmental pollution and infection with the ultimate goal of improving human nutrition.

There are two forms of isotopes tracers: Stable isotopes and radioactive isotopes.

Radioactive isotopic tracers can be measured by the radiation they emit.  While these types of tracers are often used in environmental studies or medical diagnosis, stable isotopes are usually used in nutritional studies, especially those involving infants and young children.

Stable isotopes do not emit radiation.  In nature, most elements occur as a mixture of two or more isotopes, which differ only in the number of neutrons present in their nuclei.

Stable isotopes can be given orally in water, food, or a capsule.  Depending on the rate of absorption, these stable isotopes will be incorporated into metallic products, such as body water, urea, or carbon dioxide that the body produces.  By measuring these metabolic products in saliva, breast milk, urine, breath, or stool, the ratio of minor to major isotopes can be determined.

3.         NUCLEAR TECHNIQUES FOR COMBATING MALNUTRITION:

Here are three major nuclear techniques:

3.1        Micronutrients: 

Micronutrients play an essential role in the metabolic processes of the human body, but are only required in small quantities.  Because of their essential role, when micronutrients are not sufficient from food in the diet, significant health problems can result.  Around the world, approaches to improve the intake of staple foods, modification of traditional diets, and control of parasites and infections.

Information about the nutritional status of individuals and populations is essential in order to initiate any intervention.  The information comes from evaluating measurements of nutrient requirements and studies of the uptake and bioavailability of vitamins and minerals.  Over the last 20 years, development in nuclear science has provided new techniques and methods that are today being used to gather such information.

The uptake and metabolism of micronutrients labelled with stable isotopes can be traced in vivo (A Latin term measuring “In Life” and used to describe a test in a living being rather than a test tube).  Because stable isotopes have virtually no health risk in their use, they can be used in measured amounts to trace how the body metabolizes the micronutrients.  The technique is considered to be the “Gold Standard” for iron and other nutrient bioavailability studies in humans.  It is being widely used to measure the effectiveness of fortification and supplementation programmes in several developing countries.Slide3The IAEA is funding projects worldwide aimed at developing effective strategies to combat micronutrient malnutrition in developing countries using isotopic and nuclear techniques.  These techniques are effective in both evaluating the source of deficiency and the effectiveness of the intervention as illustrated in the methodology presented under figure 22-03.  Here is a perspective about maintaining the nutritional balance:

  • Human bodies use food energy (Calories) to fuel muscle movements and metabolic processes.  Too few calories sap the body of needed strength for day-to-day activities and, over time, can be a serious threat to health.  Too many calories can cause weight gain and related health complications, such as diabetes and heart disease.  Rates of overweight and obesity have been rising steadily over the past century.  According to the WHO, more than 1 billion adults worldwide are overweight and at least 30 million are clinically obese.

3.2       Body Composition:

Doubly labelled water (2H2 18O) – So called because both the hydrogen and oxygen components of water are labelled with stable isotopes – is the only technique available to accurately measure how much food energy people use.  Here is an example:Slide4

Determining lean body mass and flat mass can help identify risks for over-nutrition.  While it is a well-recognized problem in developing countries, obesity is an increasing problem in countries considered to be in “Nutrition Transition”.

 

A dose of labelled water (2H or 18O) is given and allowed to equilibrate for a few hours.  The extent of dilution of the tracer in body water is measured sampling saliva, urine or plasma.  Total body water (TBW) is then calculated using a specific equation.  TBW is used to quantify lean body mass.  Fat mass is the difference between body weight and free fat mass.

 

Duel Energy X Ray Absorptiometry (DEXA) uses low energy X rays to measure body composition, especially home mineral density.  By determining how much of the X rays are absorbed by the hone, DEXA can precisely determine the bone mineral content.  Data can be standardized for age, weight, height, and ethnicity, making it the technique of choice for assessing bone mineral density.

3.3       Breast Milk Intake:

Breastfeeding is the simplest, healthiest, and least expensive way to feed infants.  However, a nursing infant’s nutrition depends on both the quantity and quality of the mother’s milk.

The IAEA is providing technical support to use stable isotopes as a part of the research to study how supplementation programmes for nursing mothers are affecting their breast milk.  The World Bank and World Food programmes also support this research.

The results showed that breast milk output was not influenced by supplementation 60 days before delivery, however the quality of the milk, particularly the lactose, total protein, and zinc contents increased significantly in supplemented mothers.  Here is an example to illustrate the process:Slide54.         CONCLUSION:

Good nutrition is vital to good health and a sustainable future.  To achieve the goal set by the World Food Summit to halve hunger and malnutrition by 2015, effective programmes and a sustainable commitment by governments, non-government organizations, international organizations, and the private sector will be required.

Nuclear science is being used by more and more countries around the world to evaluate the effectiveness of nutritional interventions and can help guide the development of sound nutrition policies.

The IAEA is offering technical solutions to improve nutrition monitoring techniques and effective strategies for nutrition intervention schemes, through the use of nuclear and isotopic techniques.  These techniques, now considered among the best methods for studying the uptake and bioavailability of important nutrients, are being used in developing countries as tools to measure the success of their programmes against malnutrition.

Resources:

  1. The Free Dictionary – Malnutrition;
  2. The Free Dictionary – Vitamins;
  3. Malnutrition Matters;
  4. Wikipedia – Causes;
  5. Wikipedia – Tuberculosis;
  6. Wikipedia – World Health Organization;
  7. The 6th Report on World Nutrition Situation;
  8. Stable isotope techniques to develop and monitor nutrition programmes; and
  9. Improving Nutrition through Nuclear Science.

 

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