ABSTRACT
Los estudios observacionales han demostrado, de manera consistente, una asociación positiva entre el consumo de dietas ricas en frutas y vegetales, y un menor riesgo de enfermedad cardiovascular, cáncer, enfermedad cerebrovascular y otras enfermedades crónicas. El consumo de suplementos de vitaminas antioxidantes ha ido en aumento, bajo la premisa de que estos podrían ayudar a prevenir o curar enfermedades crónicas. Sin embargo, a pesar de la gran cantidad de investigaciones que se han realizado en este campo, no se ha logrado esclarecer realmente el papel que la suplementación con estos micronutrientes pueda estar ejerciendo en la patología de esas enfermedades. El Instituto Nacional de Salud de los Estados Unidos establece, que no existe, suficiente evidencia científica para promover o desestimular, el uso de suplementos multivitamínicos para la prevención de las enfermedades crónicas. Los datos emergentes cuestionan los beneficios reales que los suplementos antioxidantes puedan tener en los sujetos con un adecuado estado nutricional, y sugiere que su consumo podría no ser seguro en comparación con las vitaminas y minerales contenidos naturalmente, en los alimentos. Los meta-análisis realizados, con estudios randomizados no han logrado demostrar efectos benéficos de la suplementación con multivitaminas sobre la mortalidad por enfermedades crónicas, y más bien, algunos análisis han sugerido que los B-catorenos, la vitamina A y la vitamina E podrían aumentar el riesgo de muerte.
Observational studies have consistently demonstrated a positive association between high fruits and vegetables intake and a reduced risk of heart disease, cancer, cerebrovascular disease, and other chronic diseases. Under the premise that vitamin and mineral supplements can have thesame effects of those naturally found in food, many people are using them to prevent or treat chronic diseases. But in spite of intensive research, the benefitial effect of antioxidant supplements is still not clear. The US National Institute of Health states that there is not enough evidence torecommend or discourage the use of multivitamin supplements to prevent chronic diseases. Growing scientific data questions the benefitial value of supplementing with antioxidant vitamins,in well nourished population and raises the possibility that they may not be safe compared with vitamin consumption within a healthy diet. Meta-analyses of randomized trials have failed todemonstrate that supplementations with antioxidant vitamins can have benefitial effects on mortality. Even more, some analyses suggested that β-carotenes, vitamin A or vitamin E can increase the risk of death.
Subject(s)
Humans , Chronic Disease , Dietary Supplements , Micronutrients , Minerals , Micronutrients/standards , VitaminsABSTRACT
Micronutrient malnutrition, particularly vitamin A deficiency (VAD), iron deficiency anaemia (IDA) and iodine deficiency disorders (IDD), poses a serious threat to the health of vulnerable segments of population. Dietary Inadequacy is the primary cause of VAD and IDA, while poor iodine content of soil and water due to environmental iodine deficiency is the main determinant of IDD. Three major intervention strategies are available for the control of micronutrient malnutrition: supplementation of the specific micronutrients; fortification of foods with micronutrients; and horticulture intervention to increase production and nutrition education to ensure regular consumption of micronutrient rich foods. In India currently the national nutrition programmes being implemented for preventing these deficiencies are based on short term supplementation like periodic mega dosing of vitamin A, distribution of iron and folic acid tablets, and salt iodisation. Though these have been in operation for over two decades, there has been no perceptible biological impact on the prevalence of micronutrient malnutrition. Among the constraints, the most important are: lack of coordination, shortage of resources and manpower, inadequate and irregular supplies, lack of proper orientation and training to the functionaries, poor monitoring and supervision and absence of nutrition education. Integrated and multi-sectoral approaches are required to achieve the goals set under the National Nutrition Policy. These should include community-friendly nutrition education to increase awareness and motivation; active people's participation; food fortification; nutrient supplementation; nutrition oriented horticulture programmes; orientation of functionaries, and establishment of integrated micronutrient surveillance. Concerted and focussed efforts are needed to combat micronutrient malnutrition by the 2000 AD.