Consumption of Nuts and Similar Dried Foods in Portugal and Level of Knowledge about their Chemical Composition and Health Effects

Document Type : Research Article


1 CERNAS Research Centre, Polytechnic Institute of Viseu, 3504-510 Viseu, Portugal

2 Department of Food Industry, Agrarian School of Viseu, 3500-606 Viseu, Portugal

3 Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, 5300-253 Bragança, Portugal



Nuts are consumed worldwide and have valuable nutritional compositions. However, few studies exist about the consumers’ knowledge regarding nuts and similar dried fruits. This study aimed to investigate the knowledge on nuts composition (KNC) and health effects (KNHE) associated with nuts consumption and evaluate eating habits and preferences. A questionnaire survey was applied by direct interview to 300 Portuguese citizens, recruited by convenience. Anthropometric properties, behavioural and health aspects, knowledge about nuts composition and health effects, and consumption habits and preferences were evaluated and statistically analysed. Globally, the participants were not well informed on the chemical composition of nuts and about their effects on human health. Regarding age, the middle-aged adults showed a little higher level of KNC. However, no statistical differences were observed for KNC and KNHE across groups of Body Mass Index, physical exercise practice or balanced diet. Concerning eating habits and preferences, most participants (84%) like nuts, and usually consume them (58%). Among different nuts, the most consumed ones were peanuts and walnuts, followed by almonds and hazelnuts. A vast majority of participants (86%) preferred to eat the nuts in their simple form and consume them between meals. In conclusion, improvement of communication on nuts benefits to human health might be a way to increase their consumption. Our data can also help the nut industries to formulate a better strategy.


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