Evaluation of nutrients in bread: a systematic review

BACKGROUND: A balanced and optimized amount of nutrients in bread, which is the main food in many countries, is necessary to maintain human health. Considering the importance of nutritional values of bread in the food basket of Iranian households, the purpose of this study was to determine the nutrients and their concentrations in breads consumed in Iran.

METHODS: This systematic review study was performed to determine the types of nutrients in breads consumed in Iran by searching reputable international databases including Scopus and Google scholar, PubMed, Science direct, ISI (Web of Science). Data were collected according to inclusion and exclusion criteria and by searching for relevant keywords, emphasizing the types of nutrients in breads consumed in Iran. Qualitative data were collected using the standard PRISMA checklist (preferential reporting items for systematic reviews and meta-analysis). After verifying the quality of the articles, the information was entered into a checklist such as the name of the first author and year of publication of the research, type of study, number of samples, type of nutrition, type of bread and amount of nutrition measured.

RESULTS: After reviewing the information and quality of articles, 10 articles were qualified for systematic review. The review of the articles showed that different breads were experimented, including: Sangak, Barbari, Taftoon, Lavash, French and local bread. The highest number of experimented bread samples was Sangak. Examination of the articles showed that 6 nutrients were experimented in different breads such as Fe, K, Mg, Ca, Cu and Zn. The highest number of experimented in breads was related to the amount of Zn (13 times) and Cu (10 times), respectively. The results of quality assessment of articles showed that most of the studies were of good quality. The results of articles on the amount of nutrients measured in different breads showed that only in two articles the amount of nutrients was reported to be desirable. In most articles, the amount of nutrients in breads was reported to be lower or higher than standard.

CONCLUSION: The results of this study showed that the concentration of nutrients in most articles was undesirable. It is suggested that optimal methods of enrichment of breads and flours be done with interdisciplinary cooperation between food hygiene, environmental health, nutrition, farmers and bakers. It is recommended that food hygiene and environmental health researchers investigate other nutrients (including phosphorus, selenium, manganese, boron and molybdenum) in breads and other staple foods used by people to constructive and practical measures to increase public health.