In partnership with the all party Parliamentary and Scientific Committee, the Nutrition Society were delighted to host a discussion meeting at the Houses of Parliament on 26 October 2020, titled “Sources, health benefits and global challenges of protein”.

Chaired by Stephen Metcalfe MP, the invited panel were Professor Ailsa Welch, University of East AngliaAssistant Professor Jorn Trommelen, Maastricht University, and Professor Andy Salter, University of Nottingham.


Animal products are major dietary sources of protein, an essential nutrient for growth and repair of the body, and maintenance of good health. With the global population placing a significant increase in demand for animal-based protein sources, it is expected to have a negative environmental impact. Action is therefore required to switch to alternative sources of protein that meet dietary requirements and move towards a more sustainable society.

The panel discussion 

Dr Jorn Trommelen began proceedings by explaining the importance of adequate protein intake to ensure muscle mass and function is maintained. Whilst children and young adults typically consume enough protein to meet requirements, older adults (>65 years) are at risk of inadequacy and accelerated age-related muscle loss due to having higher requirements than the current Reference Nutrient Intake suggests. As dietary protein requirements are also dependent on the quality of protein ingested, Dr Trommelen highlighted that when considering plant-based sources of protein as a sustainable alternative to animal-based sources, we should be cautious when recommending such diets (typically of lower protein content and quality) to older adults who are already at risk of protein inadequacy.   

Professor Ailsa Welch then focused on the impact of poor diet quality on health and ageing, showing that whilst some loss of muscle mass over time is to be expected, accelerated decline in muscle power is associated with frailty, osteoporosis and sarcopenia which impact on quality-of-life and increase the risk of morbidity. Professor Welch explained that both diet and exercise are important modifiable factors that can slow this progressive decline provided evidence that a balanced diet rich in micronutrients, coupled with regular physical activity is an effective way to prevent the risk of age-related chronic disease.

Professor Salter finished the panel discussion by highlighting the need to consider the environmental impacts of our diet when meeting protein requirements, as the global population continues to grow. Professor Salter discussed the role of novel protein sources in sustainably meeting future protein requirements; referring to The Future Proteins Platform, to highlight current protein sources being explored and the advantages and disadvantages of switching to these novel food sources including cultured meat and fungus. There is also an increased interest in the production of bacterial species as protein rich ingredients with a good animal acid profile for both food and animal feed.

The panel agreed that whilst adequate protein intake is important to minimise age-related decline in muscle mass, physical activity is crucial in ensuring effective protein uptake and both lifestyle and diet can significantly contribute to healthy ageing. 

In order to meet the protein demands for the growing world population, fundamental changes in current food systems are required, and novel sources of protein offer the potential to make a vital contribution to future human food and animal feed. However, important considerations to protein content and quality are needed when switching to more sustainable sources to ensure requirements in those at risk of inadequacy are still met. 

The Society would like to thank the Parliamentary and Science Committee and the panel speakers for their help supporting the meeting and look forward to hosting further nutrition related discussions in the future.