Diet and environmental impact : climate, water footprints, and biodiversity
Discover five recent scientific articles from our food, health and sustainability watch.
In order to examine whether recent obesity prevalence trends are in line with the diffusion of innovations theory, a team of researchers in the Netherlands studied long-term trends (from 1978 to 2019) by socioeconomic group (SEG) in England, France, Finland, Italy, Norway, and the USA. In all countries, except among American men, lower educated groups had higher obesity prevalence than higher educated ones over the entire examined period. Increases across educational groups were comparable until about 2000. A stagnation was then observed in obesity prevalence, first among higher educated in Finland, France, Italy, and Norway, followed then by lower and middle educated Italian women and Finnish men, and lower educated groups in USA and England. This stagnation observed in most countries is consistent with the diffusion of innovations theory and might be explained by early implementation of health prevention behaviours (increasing physical activity and reducing ultra-processed food and calorie intake). However, the fact that recent stagnation is mainly observed by higher SEG in most countries implies that lower SEG are likely to face the future burden of obesity and that, as a result, inequalities may widen further
In many Western countries most children do not eat enough vegetables. Innovative and pragmatic ways are then needed to increase their daily intake. According to a team of English researchers, increasing children’s exposure to vegetables at breakfast from an early age would allow for the development of a positive association between eating vegetables and breakfast, thus providing another opportunity in the day where vegetables might be regularly consumed by children. While the habit of serving vegetables for breakfast is unusual, yet there is no nutritional, physiological or medical reason why they should not be eaten then. This paper highlights the reasons why, conversely, vegetables should be routinely offered to young children at breakfast time in countries where this may not be the norm. However, the feasibility and acceptability of such intervention should be assessed.
Jennie Macdiarmid from University of Aberdeen gave a plenary lecture on this topic during The Nutrition Society Summer Conference 2021. She highlighted the challenges of the trend towards a plant-based diet, a foundation for healthy sustainable diets. As consumers perceive plant-based diets as inconvenient, the emerging ‘modern’ plant-based diet is very different from a more traditional diet of pulses, vegetables, and whole grains. Many produced plant-based foods are in fact ultra-processed, high in energy, fats, sugar, and salt and thus, present a concern as regard to both public health and environmental impact. Indeed studies show that younger people who have been vegetarians for a short duration consume much more ultra-processed plant-based foods. While convenient, desirable and affordable plant-based foods have their place in encouraging dietary change towards a more sustainable diet, there is a need to ensure that they do not unconsciously lead to a shift that is ultimately neither healthy nor sustainable.
A recent narrative review including 18 studies presents the association between dietary patterns or food groups and sarcopenia. Mediterranean and Japanese dietary patterns were associated with lower sarcopenia prevalence while Western diet was significantly associated with a higher risk. Beyond the well-documented significant association between protein intake and sarcopenia, an increased intake of fruit, vegetables, and both fruit and vegetables, was significantly associated with a lower risk of sarcopenia. These findings highlight the key role of diet for the prevention and treatment of sarcopenia among older adults.
A recent study estimates the effect of carbon footprint labels on individual food choices and quantifies potential carbon emission reductions. This work is based on data from a large-scale field experiment at five university cafeterias with over 80,000 individual meal choices. Findings show that this type of label has statistically significant impacts on meal choices, with a consumer shift from high-carbon to mid-carbon impact meals by 2.7 percentage points. However, no effect was observed on low carbon meal choices. Carbon footprint labels has also led a transition from meat and fish-based dishes towards vegan/vegetarian dishes by 1.7 percentage points. Likewise, results showed that carbon footprint labels caused a reduction of 27 g CO2 in the average footprint consumed per 100 g servings.