Protein intakes of vegetarians are generally lower than those of non-vegetarians but still meet UK dietary recommendations. Jackson (1993) calculated the average intake of protein by vegetarians in the UK to be 57g/day, compared with 75g/day for non-vegetarians. Draper (1993) found protein intake in vegetarians to be 66g/day for men and 56g/day for women. UK recommendations are 55g/day for men and 45g/day for women.
Vegetarians eating a balanced diet obtain protein from a variety of food sources. This means essential amino acid requirements can be met by plant foods. The idea of combining proteins from different plant sources to provide all of the necessary essential amino acids is known as protein complementing. Previous emphasis on protein complementing has been overstated and it is now widely accepted that it is not something vegetarians eating a balanced diet need consider.
In fact, the lower protein intake of vegetarians may be beneficial as there is concern that high protein intake may be associated with health risks. Poor or failing kidney function may be aggravated and the loss of calcium from bones increased by excessive dietary protein. In both instances, animal protein appears to be more harmful than plant protein. A high intake of animal protein may also play a contributory role in raised blood pressure (Bursztyn, 1985).