With an ageing population, dietary approaches to promote health and independence later in life are needed. In part, this can be achieved by maintaining muscle mass and strength as people age. New evidence suggests that current dietary recommendations for protein intake may be insufficient to achieve this goal and that individuals might benefit by increasing their intake and frequency of consumption of high-quality protein. However, the environmental effects of increasing animal-protein production are a concern, and alternative, more sustainable protein sources should be considered. Protein is known to be more satiating than other macronutrients, and it is unclear whether diets high in plant proteins affect the appetite of older adults as they should be recommended for individuals at risk of malnutrition. The review considers the protein needs of an ageing population (>40 years old), sustainable protein sources, appetite-related implications of diets high in plant proteins, and related areas for future research.

Human dietary patterns are a major cause of environmental transformation, with agriculture occupying ~ 50% of global land space, while food production itself is responsible for ~ 30% of all greenhouse gas emissions and 70% of freshwater use. Furthermore, the global population is also growing, such that by 2050, it is estimated to exceed ~ 9 billion. While most of this expansion in population is expected to occur in developing countries, in high-income countries there are also predicted changes in demographics, with major increases in the number of older people. There is a growing consensus that older people have a greater requirement for protein. With a larger and older population, global needs for protein are set to increase. This paper summarises the conclusions from a Rank Prize funded colloquium evaluating novel strategies to meet this increasing global protein need.

Sustainable diets are proposed as a means to improve public health and food security and to reduce the impact of the food system on the environment. Guidance around sustainable diets includes a reduction of animal products in order to move towards a more plant‐based diet, meaning that plant‐originated foods are a predominant, but not the sole component of a diet. The main principles of a sustainable diet (as provided by the Food and Agriculture Organization of the United Nations/World Health Organization) are to consume a variety of unprocessed or minimally processed foods, mainly as wholegrains, pulses, fruits and vegetables, with moderate amounts of eggs, dairy, poultry and fish and modest amounts of ruminant meat, which are consistent with the current UK healthy eating recommendations (e.g. Eatwell Guide). The aim of this review was twofold: (i) to discuss public health challenges associated with consumers’ knowledge regarding protein sustainability, healthier protein sources and protein requirements, and (ii) to review potential approaches to facilitate the shift towards a more sustainable diet. Consumers would benefit from receiving clear guidance around how much protein is needed to meet their daily requirements. The public health message directed to a consumer could highlight that desired health outcomes, such as muscle protein synthesis and weight control, can be achieved with both sources of protein (i.e. animal and plant‐based), and that what is more important is the nature of the ‘protein package’. Health promotion and education around the benefits of plant‐based protein could be one of the strategies encouraging the wider population to consider a shift towards a predominantly plant‐based diet.

Lower income households are at greater risk of food insecurity and poor diet quality than higher income households. In high-income countries, food insecurity is associated with high levels of obesity, and in the UK specifically, the cost of living crisis (i.e., where the cost of everyday essentials has increased quicker than wages) is likely to have exacerbated existing dietary inequalities. There is currently a lack of understanding of the impact of the current UK cost of living crisis on food purchasing and food preparation practices of people living with obesity (PLWO) and food insecurity, however this knowledge is critical in order to develop effective prevention and treatment approaches to reducing dietary inequalities. Using an online survey (N = 583) of adults residing in England or Scotland with a body mass index (BMI) of ≥30 kg/m², participants self-reported on food insecurity, diet quality, perceived impact of the cost of living crisis, and their responses to this in terms of food purchasing behaviours and food preparation practices. Regression analyses found that participants adversely impacted by the cost of living crisis reported experiencing food insecurity. Additionally, food insecurity was associated with use of specific purchasing behaviours (i.e., use of budgeting, use of supermarket offers) and food preparation practices (i.e., use of energy-saving appliances, use of resourcefulness). Exploratory analyses indicated that participants adversely impacted by the cost of living crisis and who used budgeting had low diet quality, whereas use of meal planning was associated with high diet quality. These findings highlight the fragility of food budgets and the coping strategies used by PLWO and food insecurity during the cost of living crisis. Policy measures and interventions are urgently needed that address the underlying economic factors contributing to food insecurity, to improve access to and affordability of healthier foods for all.

The potential beneficial effects of plant-based diets on human health have been extensively studied. However, the evidence regarding the health effects of extracted plant-based proteins as functional ingredients, other than soya, is scarce. The aim of this review was to compile evidence on the effects of extracted protein from a wide range of traditional and novel plant sources on glycemic responses, appetite, body weight, metabolic, cardiovascular and muscle health. A comprehensive search of PubMed, EMBASE and The Cochrane Central Register of Controlled Trials (CENTRAL) was conducted through 23 and 27 March 2020 for randomized controlled trials that featured any of the following 18 plant protein sources: alfalfa, duckweed, buckwheat, chickpea, fava bean, hemp, lentil, lupin, mushroom, oat, pea, potato, pumpkin, quinoa, rapeseed, rice, sacha inchi, sunflower. Only interventions that investigated concentrated, isolated or hydrolysed forms of dietary protein were included. Searched health outcome measures were: change in blood glucose, insulin, satiety hormones concentration, subjective assessment of appetite/satiety, change in blood lipids concentration, blood pressure, body weight and muscle health parameters. Acute and sub-chronic studies were considered for inclusion. Applying the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) approach we identified 1190 records. Twenty-six studies met the inclusion criteria. Plant protein sources used in interventions were most often pea (n = 16), followed by lupin (n = 4), fava bean (n = 2), rice (n = 2), oat (n = 2), hemp (n = 2) and lentil (n = 1). Satiety and postprandial glycemic response were the most frequently reported health outcomes (n = 18), followed by blood lipids (n = 6), muscle health (n = 5), body weight (n = 5) and blood pressure (n = 4). No studies on the remaining plant proteins in the extracted form were identified through the search. Most studies confirmed the health-promoting effect of identified extracted plant protein sources across glycemic, appetite, cardiovascular and muscular outcomes when compared to baseline or non-protein control. However, the current evidence is still not sufficient to formulate explicit dietary recommendations. In general, the effects of plant protein were comparable (but not superior) to protein originating from animals. This is still a promising finding, suggesting that the desired health effects can be achieved with more sustainable, plant alternatives. More methodologically homogenous research is needed to formulate and validate evidence-based health claims for plant protein ingredients. The relevance of these findings are discussed for the food sector with supporting market trends.

Similar to other countries, trends of decreasing levels of physical activity (PA) and an increasing prevalence of unhealthy dietary patterns are observed among girls in Poland. Better understanding of potentially inter-related behaviours within this population can help to design tailored interventions. The purpose of this study was to determine associations between PA patterns and dietary patterns in a representative sample of Polish girls. Girls aged 13-21 years (n = 1107) were randomly selected for the study. PA was assessed using International Physical Activity Questionnaire – Long (IPAQ-L). Dietary data were collected with food frequency questionnaires. PA patterns and dietary patterns were drawn separately by Principal Component Analysis (PCA). Logistic regression was used to find the associations between PA patterns and dietary patterns. Four major PA patterns (‘School/work activity’, ‘Active recreation’, ‘Yard activity’ and ‘Walking and domestic activity’) and four dietary patterns (‘Traditional Polish’, ‘Fruit & vegetables’, ‘Fast food & sweets’ and ‘Dairy & fats’) were identified. Level of PA was the highest in the upper tertile of ‘School/work activity’ pattern (mean 1372.2 MET-minutes/week, 95 % Confidence Intervals [CI]: 1285.9–1458.5). Girls in upper tertiles of ‘Yard activity’, ‘Active recreation’ and ‘School/work activity’ patterns had significantly higher chances of being in the upper tertile of the ‘Fruit and vegetables’ dietary pattern (odds ratio [OR] 2.17, 95 % CI: 1.50–3.14, p < 0.0001; OR 2.02, 95 % CI: 1.41–2.91; p < 0.001 and OR 1.76, 95 % CI: 1.24–2.51, p < 0.01 respectively; all adjusted for confounders) in comparison to bottom tertiles. Weak, but significant inverse associations were found between upper tertiles of ‘Active recreation’ and ‘Yard activity’ patterns and unhealthy dietary patterns. We found associations between PA patterns and dietary patterns in the population of Polish girls. Girls with the highest adherence to the ‘School/work activity’ pattern had the highest levels of PA and presented pro-healthy dietary behaviours. School should be recognised as potentially efficient and important setting to maximise girls' PA potential. The after-school time is the area that should also be targeted to increase daily PA or to at least sustain the level of PA after completing education.