https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(13)60937-X.pdf

Maternal and child undernutrition and overweight in low-income and middle-income countries

Food and Agricultural Organization of the United Nations PA N I S F I A T G u id e in e s o n fo o d fo r tific atio n w th m ic r o n u tr ie n ts Interest in micronutrient malnutrition has increased greatly over the last few years. One of the main reasons is the realization that micronutrient malnutrition contributes substantially to the global burden of disease. Furthermore, although micronutrient malnutrition is more frequent and severe in the developing world and among disadvantaged populations, it also represents a public health problem in some industrialized countries. Measures to correct micronutrient deficiencies aim at ensuring consumption of a balanced diet that is adequate in every nutrient. Unfortunately, this is far from being achieved everywhere since it requires universal access to adequate food and appropriate dietary habits. Food fortification has the dual advantage of being able to deliver nutrients to large segments of the population without requiring radical changes in food consumption patterns.

Guidelines on food fortification with micronutrients

Subclinical thyroid disease (SCTD) is defined as serum free T4 and free T3 levels within their respective reference ranges in the presence of abnormal serum TSH levels. SCTD is being diagnosed more frequently in clinical practice in young and middle-aged people as well as in the elderly. However, the clinical significance of subclinical thyroid dysfunction is much debated. Subclinical hyper- and hypothyroidism can have repercussions on the cardiovascular system and bone, as well as on other organs and systems. However, the treatment and management of SCTD and population screening are controversial despite the potential risk of progression to overt disease, and there is no consensus on the thyroid hormone and thyrotropin cutoff values at which treatment should be contemplated. Opinions differ regarding tissue effects, symptoms, signs, and cardiovascular risk. Here, we critically review the data on the prevalence and progression of SCTD, its tissue effects, and its prognostic implications. We also examine t...

The clinical significance of subclinical thyroid dysfunction.

The United Nations Children's Fund, or UNICEF, was originally created to provide relief for children in countries devastated by the destruction of World War II. After 1950, UNICEF turned to focus on general programs for the improvement of children's welfare worldwide, and in 1965, it was awarded the Nobel Prize for Peace for its humanitarian efforts. The organization concentrates on areas in which relatively small expenditures can have a significant impact on the lives of the most disadvantaged children in developing countries, such as the prevention and treatment of disease, child healthcare, malnutrition, illiteracy, and other welfare services.

The United Nations Children's Fund

Vitamin B12 deficiency causes reversible megaloblastic anemia, demyelinating disease, or both. Current assays have insufficient sensitivity and specificity; methylmalonic acid levels are useful to confirm diagnosis. Parenteral or high-dose oral vitamin B12 is effective therapy.

https://www.nejm.org/doi/pdf/10.1056/NEJMcp1113996

Vitamin B12 Deficiency

Objective To provide current global and regional estimates of anaemia prevalence and number of persons affected in the total population and by population subgroup. Setting and design We used anaemia prevalence data from the WHO Vitamin and Mineral Nutrition Information System for 1993-2005 to generate anaemia prevalence estimates for countries with data representative at the national level or at the first administrative level that is below the national level. For countries without eligible data, we employed regression-based estimates, which used the UN Human Development Index (HDI) and other health indicators. We combined country estimates, weighted by their population, to estimate anaemia prevalence at the global level, by UN Regions and by category of human development. Results Survey data covered 48.8 % of the global population, 76.1 % of preschool-aged children, 69.0 % of pregnant women and 73.5 % of non-pregnant women. The estimated global anaemia prevalence is 24.8 % (95 % CI 22.9, 26.7 %), affecting 1.62 billion people (95 % CI 1.50, 1.74 billion). Estimated anaemia prevalence is 47.4 % (95 % CI 45.7, 49.1 %) in preschool-aged children, 41.8 % (95 % CI 39.9, 43.8 %) in pregnant women and 30.2 % (95 % CI 28.7, 31.6 %) in non-pregnant women. In numbers, 293 million (95 % CI 282, 303 million) preschool-aged children, 56 million (95 % CI 54, 59 million) pregnant women and 468 million (95 % CI 446, 491 million) non-pregnant women are affected. Conclusion Anaemia affects one-quarter of the world's population and is concentrated in preschool-aged children and women, making it a global public health problem. Data on relative contributions of causal factors are lacking, however, which makes it difficult to effectively address the problem.

/pdf/worldwide-prevalence-of-anaemia-who-vitamin-and-mineral-4zrxzom2vw.pdf

Worldwide prevalence of anaemia, WHO Vitamin and Mineral Nutrition Information System, 1993-2005

Conclusions of a WHO Technical Consultation on folate and vitamin B12 deficiencies.

Background. Iodine deficiency is a global public health problem, and estimates of the extent of the problem were last produced in 2003. Objectives. To provide updated global estimates of the magnitude of iodine deficiency in 2007, to assess progress since 2003, and to provide information on gaps in the data available. Methods. Recently published, nationally representative data on urinary iodine (UI) in school-age children collected between 1997 and 2006 were used to update country estimates of iodine nutrition. These estimates, alongside the 2003 estimates for the remaining countries without new data, were used to generate updated global and regional estimates of iodine nutrition. The median UI was used to classify countries according to the public health significance of their iodine nutrition status. Progress was measured by comparing current prevalence figures with those from 2003. The data available for pregnant women by year of survey were also assessed. Results. New UI data in school-age children were available for 41 countries, representing 45.4% of the world’s school-age children. These data, along with previous country estimates for 89 countries, are the basis for the estimates and represent 91.1% of this population group. An estimated 31.5% of school-age children (266 million) have insufficient iodine intake. In the general population, 2 billion people have insufficient iodine intake. The number of countries where iodine deficiency is a public health problem is 47. Progress has been made: 12 countries have progressed to optimal iodine status, and the percentage of school-age children at risk of iodine deficiency has decreased by 5%. However, iodine intake is more than adequate, or even excessive, in 34 countries: an increase from 27 in 2003. There are insufficient data to estimate the global prevalence of iodine deficiency in pregnant women. Conclusions. Global progress in controlling iodine deficiency has been made since 2003, but efforts need to be accelerated in order to eliminate this debilitating health issue that affects almost one in three individuals globally. Surveillance systems need to be strengthened to monitor both low and excessive intakes of iodine.

https://journals.sagepub.com/doi/pdf/10.1177/156482650802900305

Iodine deficiency in 2007: global progress since 2003.

Objective To estimate worldwide iodine nutrition and monitor country progress towards sustained elimination of iodine deficiency disorders. Methods Cross-sectional data on urinary iodine (UI) and total goitre prevalence (TGP) in school-age children from 1993–2003 compiled in the WHO Global Database on Iodine Deficiency were analysed. The median UI was used to classify countries according to the public health significance of their iodine nutrition status. Estimates of the global and regional populations with insufficient iodine intake were based on the proportion of each country’s population with UI below 100 µg/l. TGP was computed for trend analysis over 10 years. Findings UI data were available for 92.1% of the world’s school-age children. Iodine deficiency is still a public health problem in 54 countries. A total of 36.5% (285 million) school-age children were estimated to have an insufficient iodine intake, ranging from 10.1% in the WHO Region of the Americas to 59.9% in the European Region. Extrapolating this prevalence to the general population generated an estimate of nearly two billion individuals with insufficient iodine intake. Iodine intake was more than adequate, or excessive, in 29 countries. Global TGP in the general population was 15.8%. Conclusion Forty-three countries have reached optimal iodine nutrition. Strengthened UI monitoring is required to ensure that salt iodization is having the desired impact, to identify at-risk populations and to ensure sustainable prevention and control of iodine deficiency. Efforts to eliminate iodine deficiency should be maintained and expanded.

/pdf/current-global-iodine-status-and-progress-over-the-last-3yc5ib0ovj.pdf

Current global iodine status and progress over the last decade towards the elimination of iodine deficiency

Zinc deficiency is an important cause of morbidity in developing countries, particularly among young children, yet little information is available on the global prevalence of zinc deficiency. A working group meeting was convened by the World Health Organization (WHO), the United Nations Children's Fund (UNICEF), the International Atomic Energy Agency (IAEA), and the International Zinc Nutrition Consultative Group (IZiNCG) to review methods of assessing population zinc status and provide standard recommendations for the use of specific biochemical, dietary, and functional indicators of zinc status in populations. The recommended biochemical indicator is the prevalence of serum zinc concentration less than the age/sex/time of day-specific cutoffs; when the prevalence is greater than 20%, intervention to improve zinc status is recommended. For dietary indicators, the prevalence (or probability) of zinc intakes below the appropriate estimated average requirement (EAR) should be used, as determined from quantitative dietary intake assessments. Where the prevalence of inadequate intakes of zinc is greater than 25%, the risk of zinc deficiency is considered to be elevated. Previous studies indicate that stunted children respond to zinc supplementation with increased growth. When the prevalence of low height-for-age is 20% or more, the prevalence of zinc deficiency may also be elevated. Ideally, all three types of indicators would be used together to obtain the best estimate of the risk of zinc deficiency in a population and to identify specific subgroups with elevated risk. These recommended indicators should be applied for national assessment of zinc status and to indicate the need for zinc interventions. The prevalence of low serum zinc and inadequate zinc intakes may be used to evaluate their impact on the target population's zinc status.

https://journals.sagepub.com/doi/pdf/10.1177/15648265070283S306

Bruno de Benoist

Papers

Worldwide prevalence of anaemia, WHO Vitamin and Mineral Nutrition Information System, 1993-2005

Conclusions of a WHO Technical Consultation on folate and vitamin B12 deficiencies.

Iodine deficiency in 2007: global progress since 2003.

Current global iodine status and progress over the last decade towards the elimination of iodine deficiency

Conclusions of the Joint WHO/UNICEF/IAEA/IZiNCG Interagency Meeting on Zinc Status Indicators.