Breastfeeding (BF) is an eco-friendly, sustainable, and non-polluting form of feeding compared to formula feeding (FF) (for definitions of infant feeding types, see Annex I). It results in less waste production, minimal greenhouse gas (GHG) emissions, a smaller carbon footprint (see definitions of the environmental impacts referred to in this article in Annex I), and smaller water footprint (WF) [1, 2]. According to the Convention on the Rights of the Child [3], all infants and children have the right to the enjoyment of the highest attainable standard of health. The World Health Organization (WHO) recommends that BF be exclusively used for the first six months of life and that it be continued up to two years of age or for as long as the mother and child wish. BF offers multiple physical and mental health benefits for both mother and child and is environmentally friendly [2,3,4].

Some of the short-term benefits to children’s health include reduction of neonatal mortality, protection against gastrointestinal and respiratory infections, dental malocclusion and atopy [5,6,7]. In the long term, children and teenagers who were breastfed are less likely to be overweight or obese, are more likely to have healthier cognitive development and score better on intelligence tests, are associated with a higher income as adults, and are less likely to suffer diabetes or cardiovascular disease throughout their lives [4, 6]. Longer exclusive breastfeeding (EBF) also contributes to the health and well-being of mothers [4, 5]. It reduces the risk of ovarian and breast cancer, helps space out pregnancies, and decreases the risk of type 2 diabetes [4,5,6]. Improved child development and reduced healthcare costs thanks to BF result in financial savings for families, the nation, and society in general [2].

Under the Paris Agreement, the European Commission has set ambitious goals to reduce the continent’s carbon footprint, including a 55% reduction in GHG emissions by 2030 and climate neutrality by 2050 [8].

The manufacture and distribution of industrial infant formula is harmful to the environment, generates polluting waste, and requires energy use to manufacture the formula and packaging materials, and to transport the products, and water use to prepare bottles on a daily basis. Most infant formulas are based on cow's milk. Dairy farms represent the main source of anthropogenic methane emissions. In Europe, livestock farming represents 12–17% (630–863 Mt CO2-eq) of total GHG emissions [8].

For an accurate calculation of the environmental impact of breastfeeding, the infant feeding accessories (breast milk pump; milk storage containers or bags, bottles, bottle warmer, and bottle sterilizer, for example) and a theoretical increase of 500 kcal in the diet of the mother must be taken into account [1, 9,10,11,12].

There is data on the carbon footprint and water footprint of FF, but there is none on the environmental impact of breastfeeding. The average carbon footprint of FF was estimated to be 9.2, 7, 8.4, and 11 kg CO2-eq per kg of formula in New Zealand, USA, Brazil, and France, respectively. The potential carbon savings of BF compared to FF for the UK, China, Brazil and Vietnam is 40–55% [1].

The additional volume of water that a mother consumes while breastfeeding is minor compared to the significant quantities needed for manufacturing formula milk [12]. Research conducted by Pope et al. in the United States demonstrated that producing 1 kg of commercial formula requires 6.6 kg of raw milk, which entails a water footprint (WF) comprising 626 L of blue water for manufacturing, reconstitution, and sterilization, 6,280 L of green water for cow feed, and 524 L of grey water [13]. In Switzerland, Rollins and colleagues estimated that the average WF for whole cow's milk is around 940 L of water per kg of raw milk. When considering that 1 kg of whole milk produces about 200 g of milk powder, the water consumption (WC) amounts to 4,700 L of water per 1 kg of milk powder [14, 15].

Globally, water scarcity presents a significant challenge in fulfilling the need for freshwater for drinking and agricultural purposes [16]. In Spain, food consumption is associated with a water wastage of 3,302 L per person per day. The most substantial environmental impact from water use is attributed to the production of meat, fish, and animal fats (26%), as well as dairy products (21%) [17]. The water footprint of food waste was estimated to be 2,095 hm3, equivalent to 131 L per person per day [17]. Given the heightened water stress, this study also assesses the water stress implications of the life cycle of formula production, infant feeding accessories, and maternal dietary practices. There is currently no rigorous data on the GHG savings that Europe could achieve by taking into account the dietary habits of postpartum mothers if BF was their top choice rather than FF. To meticulously compare the contribution of EBF and FF to global warming in terms of their carbon footprint, the various dietary patterns of postpartum women and the accessories required for breastfeeding must be considered. Although there is no consensus on the need to supplement the diet of lactating mothers, it is recommended that they increase their daily calorie intake by 500 kcal to cover the nutritional and energy requirements of feeding their baby [18, 19]. Additionally, to promote public health, the Catalan government issued specific nutritional guidelines for pregnant women [20].

Currently, 92% of mothers want to breastfeed their babies but only 17% do EBF for six months [21]. Stopping BF is most often not the mother’s wish and happens earlier than desired. The most frequent causes of stopping breastfeeding are social barriers [22]. Mothers and families need support to ensure that their children receive optimal BF during the first six months of life, as well as the progressive and appropriate introduction of complementary feeding. Healthcare professionals play an essential role in providing this support [23].

The WHO recommends the support of health services in providing advice on infant and child nutrition. It is committed to supporting countries in accordance with the Global Nutrition Targets approved by Member States [24]. One of these targets is to increase the rate of EBF during the first six months of life to at least 50% [24].

In the 2019 document Green Feeding Europe, the Council of the European Union makes a collaborative effort with institutions to inform and involve the Green Parties of Europe, so they include the nutrition of infants and young children in their environmental programmes [12].

In the face of the climate emergency, it is crucial to understand the impact of maternal diet on health and the environment. A change towards a healthier and more environmentally friendly diet should be promoted, while increasing the rates of exclusive breastfeeding can be considered an issue related to public health, social rights, and inequality. Government investment and changes in these areas must be achieved, including longer maternity leave, spaces where women can breastfeed freely and comfortably, the monitoring of surrogate advertising, more promotion of breastfeeding and access to professionals.

To our knowledge, there are no studies on the environmental benefits of breastfeeding, or the quality and type of diet followed by postpartum women in Catalonia, Spain. Therefore, measuring the environmental benefit of breastfeeding may help protect the environment and consequently the health of the population and the planet [25, 26].

This project is split into two independent sequential projects. The results from Phase I will bolster the development of educational materials to be used in Phase II (educational intervention to improve prevalence of breastfeeding and a sustainable diet).

Hypothesis

EBF will have smaller environmental impact than FF or mixed feeding (MF).

General Aim

Calculate and compare the environmental impacts (climate change, water consumption and water scarcity) of three infant feeding types (EBF, FF, and MF).

Objectives of the study

Primary objective

Determine the environmental impacts (climate change, water consumption and water scarcity) of EBF, MF and FF of postpartum mothers in their baby’s first month of life, taking into account the accessories used for infant feeding and mother´s diet and food consumption habits.

Secondary objectives:

To calculate the prevalence of EBF, FF and MF after birth, and at 4–6 weeks postpartum.

To describe the maternal diet in terms of macro, micronutrients and energy consumed.

To compare the calories consumed by according to the type of breastfeeding, lactating mothers (EBF and MF) and non-lactating mothers (FF).

To compare feeding types with socio-demographic and clinical data.

To compare maternal diet and food consumption habits with feeding type and socio-demographic data.