This is the type of dietary pattern featured in healthy eating guidelines around the world, where predominantly plant-based diets are complemented by animal derived ingredients. More recently, it has also been recognized that a dietary pattern such as this has a lower environmental impact, particularly in relation to its carbon footprint.
For most of us, achieving dietary recommendations means eating more of some types of food, particularly fibre-containing vegetables, wholegrains, pulses and fruit. It also means diversifying the sources of protein we choose, to incorporate more plant sources, such as pulses and nuts. But it doesn’t mean eating more protein overall. The vast majority of us in the UK already exceed recommended amounts, which are 45g/day and 55g/day respectively for females and males aged 15-64 years. Children need less owing to their smaller body size. The Department of Health advises against consuming more than twice the recommended daily amount of protein.
Current protein intakes
Daily protein intakes in women and men aged 19-64 year are estimated to be 64g and 88g respectively. On average, 37% of UK adults’ protein intakes comes from meat/meat products, 23% from cereals/cereal products, 14% from milk/milk products, 10% in total from vegetables, fruit, nuts and seeds (including pulses), 7% from fish and 3% from eggs.
Protein as a marketing strategy
Investment in alternative protein sources seems to be on the increase and, despite average protein intakes exceeding recommendations, protein content is often highlighted on food packaging. Yet, ingredient decisions shouldn’t just be about protein. In formulating foods based on alternate protein sources, is consumer desire for clean labels routinely considered? Also, is inclusion of the variety of essential nutrients needed for health, which are provided generously by animal-derived foods such milk, eggs, fish and meat, being overlooked when substitute plant-derived foods are developed?
The latter is a concern from a nutritional standpoint as it is already evident that not only are the intakes of some essential nutrients relatively low among UK teenagers and young adults (particularly females), but intakes have fallen over the past decade. For example, 54% of teenage girls have iron intakes below the Lower Reference Nutrient Intake (LRNI) – by definition, we would expect just 2.5% to be below this level – compared with 43% a decade ago. About a quarter also have intakes below the LRNI for calcium, zinc, iodine and riboflavin, essential nutrients available in a readily absorbed form alongside animal derived proteins, such as in milk.
With the current emphasis on diversification of protein choices and increasing the frequency with which plant-derived sources of protein are eaten, it is more important than ever that product development considers the overall nutrient profile of foods to ensure that in changing the type of protein, the overall nutrient contribution the food makes is not compromised.
Bioavailability of nutrients
Another important consideration is the so-called bioavailability of vitamins and minerals. This is the ease with which nutrients can be absorbed and utilized by our bodies. For example, the calcium provided by milk and dairy products is absorbed relatively well compared to the calcium in some vegetables, where it is bound within the plant structure to substances such as oxalate, making the calcium less accessible.
Judy Buttriss is director general of the British Nutrition Foundation. She is part of a panel exploring nutrition issues in relation to plant-based diets for Food Manufacture's virtual conference The Future of Plant-based Proteins: Roots of Further Growth. For more details and to book tickets, see below.