[Breastfeeding for the prevention of overweight and obesity in children and teenagers; systematic review].

Background: Breastfeeding is a recommended practice from national and international institutions due to the health benefits that it provides, both for the nursling and for the mother. Nowadays, overweight and obesity result in greater morbidity along different life periods.

Objective: The goal of this systematic review is to explore the characteristics of breastfeeding in the prevention of overweight and obesity during childhood.

Method: A systematic search has been carried out and 113 papers have been selected: 20 meta-analysis and reviews, 6 original papers of clinical trials, 42 cohort or longitudinal studies, 19 correlational studies, 24 descriptive studies and 2 books.

Results: According to the analysed papers, there is a causal relationship between breastfeeding and the prevention of childhood obesity.

Discussion/conclusion: In the various studies explored, it has been observed that the maximum benefits of breastfeeding are obtained when its duration is longer than 6 months and when it extends for two years, complemented with other foodstuffs. Other studies show that breastfeeding is effective in obesity prevention, even when its duration is limited. It is also important that complementary foods are introduced after the first six months of age, so as to reduce food allergy risk and to prevent obesity. Similarly, the weight of the mother during pregnancy has been associated with childhood obesity, as well as the weight of the child when he was born and other factors like maternal smoking and socioeconomic status.