Prevalence of vitamin A deficiency in women of childbearing age in Brazil: a systematic review and meta-analysis.

Vitamin A is an essential micronutrient, especially during pregnancy. We aimed to assess the prevalence of vitamin A deficiency in Brazilian women of childbearing age. We conducted a systematic review with meta-analysis of studies that assessed vitamin A deficiency in women of childbearing age following the registered protocol (CRD42020171856). Independent peer researchers selected the studies retrieved from MEDLINE, Embase, Scopus and other sources. Data from the eligible studies were extracted in pairs and assessed for methodological quality. The prevalence of vitamin A deficiency (< 0·70 µmol/l or <0·20 µg/dl) and 95 % CI was combined by meta-analysis, and heterogeneity was estimated by I2. Out of 3610 screened records, thirty-two studies were included, which assessed 12 577 women from 1965 to 2017, mostly in maternity hospitals. Main limitations of the studies were in sample frame (30/32) and sampling method (29/32). Deficiency occurred in 13 % (95 % CI 9·4, 17·2 %; I² = 97 %) of all women and was higher in pregnant women (16·1 %; 95 % CI 5·6, 30·6 %; I² = 98 %) than non-pregnant women (12·3 %; 95 % CI 8·4, 16·8 %; I² = 96 %). The prevalence increased according to the decade, from 9·5 % (95 % CI 1·9­21·6 %; I² = 98 %) up to 1990, 10·8 % (95 % CI 7·9, 14·2 %; I² = 86 %) in the 2000s and 17·8 % (95 % CI 8·7, 29·0 %; I² = 98 %) in the 2010s. Over 10 % of Brazilian women in childbearing age were deficient in vitamin A. Higher prevalence was observed in pregnant women, and deficiency seemed to be increasing over the decades. Low representativeness of the studies, mainly based on convenience sampling that included pregnant, postpartum, lactating and non-pregnant women, as well as high heterogeneity, limits the findings.

The mandatory labeling of genetically modified foods in Brazil: Consumer's knowledge, trust, and risk perception.

Since 2003, Brazilian-specific legislation has stipulated that foods containing more than 1% of genetically modified (GM) ingredients must provide information regarding their origin with an identification symbol on its label. The purpose of this study was to verify the knowledge of consumers concerning the mandatory labeling of foods containing genetically modified ingredients and analyze the possible motivations behind the willingness of the consumer to buy these foods in Brazil. Research was conducted on 224 consumers of different socioeconomic levels from Limeira, São Paulo (SP), Brazil. Consumers were asked about socio-demographic variables and were assessed for their knowledge of the symbol for genetically modified ingredients on food labels. Depending on the consumers' answer about the symbol, they would be directed to a specific set of assertions. In the end, seventeen assertions were scored using a 5-point Likert scale to determine their profile. These assertions were categorized into five constructs: social trust, reduced price, perceived risk, perceived quality, and willingness to buy. This data was analyzed using Structural Equation Modelling. Most consumers (74.6%) did not recognize the symbol used in the mandatory labeling, although a younger age, a concern regarding GM foods, and a high level of education increased the chances of recognizing the symbol. Many of the consumers who were able to identify the symbol have found the GM labeling difficult to interpret. With regard to their willingness to buy GM foods, positive effects were observed for reduced price and perceived quality, while a negative effect was observed for risk perception. The effect of risk perception was moderated by social trust and perceived quality. These results indicate that although the Brazilian GM food label policy is aligned with similar policies in developed countries, it has been implemented without an adequate disclosure. The consumers had a high confidence with regards to the science and the government, reducing their risk perception. Our findings indicate that in order to improve the effectiveness of this food policy, the Brazilian Ministry of Health should invest in advertising the labels, targeting the elderly and individuals with lower levels of education.