A Non-Invasive Hydration Monitoring Technique Using Microwave Transmission and Data-Driven Approaches.

Dehydration in the human body arises due to inadequate replenishment of fluids. An appropriate level of hydration is essential for optimal functioning of the human body, and complications ranging from mild discomfort to, in severe cases, death, could result from a neglected imbalance in fluid levels. Regular and accurate monitoring of hydration status can provide meaningful information for people operating in stressful environmental conditions, such as athletes, military professionals and the elderly. In this study, we propose a non-invasive hydration monitoring technique employing non-ionizing electromagnetic power in the microwave band to estimate the changes in the water content of the whole body. Specifically, we investigate changes in the attenuation coefficient in the frequency range 2-3.5 GHz between a pair of planar antennas positioned across a participant's arm during various states of hydration. Twenty healthy young adults (10M, 10F) underwent controlled hypohydration and euhydration control bouts. The attenuation coefficient was compared among trials and used to predict changes in body mass. Volunteers lost 1.50±0.44% and 0.49±0.54% body mass during hypohydration and euhydration, respectively. The microwave transmission-based attenuation coefficient (2-3.5 GHz) was accurate in predicting changes in hydration status. The corresponding regression analysis demonstrates that building separate estimation models for dehydration and rehydration phases offer better predictive performance (88%) relative to a common model for both the phases (76%).

Regulatory monitoring systems of fortified salt and wheat flour in selected ASEAN countries.

BACKGROUND: Considerable efforts have been made over the past decade to address vitamin and mineral deficiencies. An increasing number of countries in the Association of Southeast Asian Nations (ASEAN) are adopting mandatory food fortification as one of the primary strategies to overcome these deficiencies. Experience shows that fortified foods can reach large parts of the population, including the poor, if the fortification is done on a mandatory rather than a voluntary basis and if the food vehicle is widely consumed. OBJECTIVE: To review the importance of regulatory monitoring as an essential component of food fortification efforts in selected ASEAN countries, with special focus on the available information on regulatory monitoring systems for iodized salt and fortified wheat flour. METHODS: The role of regulatory monitoring in strengthening food fortification programs was discussed during a joint regional meeting of the World Health Organization, UNICEF, the Flour Fortification Initiative, the Global Alliance for Improved Nutrition, the Micronutrient Initiative, and the World Bank on regulatory monitoring of salt and wheat flour fortification programs in Asia, which took place in Manila, Philippines, on 27-29 September 2011. This paper reviews the regulatory monitoring systems of selected ASEAN countries that participated in this meeting. RESULTS: Problems and challenges in regulatory monitoring systems for iodized salt and fortified wheat flour in selected ASEAN countries are identified, and a description of the role of regulatory monitoring in strengthening food fortification initiatives, particularly of salt and flour, and highlights of areas for improvement are presented. CONCLUSIONS: Regulatory monitoring consists of monitoring activities conducted at the production level, at customs warehouses, and at retail stores by concerned regulatory authorities, and at the production level by producers themselves, as part of quality control and assurance efforts. Unless there are appropriate enforcement and quality assurance mechanisms in place to stimulate compliance by food producers, i.e., regulatory monitoring, having national legislation will not necessarily lead to increased coverage of fortified products and associated outcomes.

Fortification of wheat flour and maize meal with different iron compounds: results of a series of baking trials.

BACKGROUND: Wheat and maize flour fortification is a preventive food-based approach to improve the micronutrient status of populations. In 2009, the World Health Organization (WHO) released recommendations for such fortification, with guidelines on the addition levels for iron, folic acid, vitamin B12, vitamin A, and zinc at various levels of average daily consumption. Iron is the micronutrient of greatest concern to the food industry, as some believe there may be some adverse interaction(s) in some or all of the finished products produced from wheat flour and maize meal. OBJECTIVE: To determine if there were any adverse interactions due to selection of iron compounds and, if differences were noted, to quantify those differences. METHODS: Wheat flour and maize meal were sourced in Kenya, South Africa, and Tanzania, and the iron compound (sodium iron ethylenediaminetetraacetate [NaFeEDTA], ferrous fumarate, or ferrous sulfate) was varied and dosed at rates according to the WHO guidelines for consumption of 75 to 149 g/day of wheat flour and > 300 g/day of maize meal and tested again for 150 to 300 g/day for both. Bread, chapatti, ugali (thick porridge), and uji (thin porridge) were prepared locally and assessed on whether the products were acceptable under industry-approved criteria and whether industry could discern any differences, knowing that differences existed, by academic sensory analysis using a combination of trained and untrained panelists and in direct side-by-side comparison. RESULTS: Industry (the wheat and maize milling sector) scored the samples as well above the minimal standard, and under academic scrutiny no differences were reported. Side-by-side comparison by the milling industry did indicate some slight differences, mainly with respect to color, although these differences did not correlate with any particular iron compound. CONCLUSIONS: The levels of iron compounds used, in accordance with the WHO guidelines, do not lead to changes in the baking and cooking properties of the wheat flour and maize meal. Respondents trained to measure against a set benchmark and/or discern differences could not consistently replicate perceived difference observations.

Vitamin A fortification of wheat flour: considerations and current recommendations.

BACKGROUND: Vitamin A deficiency is a major public health nutrition problem, affecting an estimated 190 million preschool-aged children and 19 million pregnant and lactating women globally, and 83 million adolescents in Southeast Asia alone. Its consequences (disorders) include xerophthalmia (the leading cause of early childhood blindness), increased severity of infection, anemia, and death. Because vitamin A deficiency is largely due to chronic dietary insufficiency of preformed vitamin A and proactive carotenoids, food fortification can offer an effective approach to prevention. OBJECTIVE: To provide guidance on fortifying wheat and maize flour milled in industrial rollers for national fortification programs in countries where vitamin A deficiency is considered a public health problem. METHODS: Critical review of the literature on the dietary gap in vitamin A intake and levels of wheat flour intake among risk groups as a basis for determining vitamin A fortificant levels. Additional review of efficacy evidence, safety and cost considerations, and country experiences related to wheat-flour fortification with vitamin A. RESULTS: Mill-rolled wheat flour is a technically fortifiable, centrally processed food vehicle that, where routinely and adequately consumed by target groups, should be considered a candidate for fortification. Vitamin A can be stable in flour under typical, ambient conditions, with processing losses estimated at approximately 30%, depending on source and premix conditions. CONCLUSIONS: Factors to guide a decision to fortify flour with vitamin A include the extent of deficiency, availability of other food vehicle options, the centrality of milling, market reach and population intake distributions of the flour products, the dietary vitamin A intake required, and associated costs. Large gaps persist in knowledge of these factors, which are needed to enable evidence-based fortification in most countries, leaving most decisions to fortify guided by assumptions. Where flour can and should be fortified, guidelines are given for providing nearly 25% of the Recommended Dietary Allowance for vitamin A to vulnerable groups consuming varying ranges of flour products. The costs will vary according to the level of fortification.