Date: 16 Jul 94 10:41:49 GMT From: taltar@beaufort.sfu.ca (Ted Altar) Subject: Vegans and Protein Newsgroups: rec.food.veg Organization: Simon Fraser University Lines: 131 VEGANS AND PROTEIN The following selection comes from what is still the single best survey of the relevant research regarding nutrition for vegans, VEGAN NUTRITION (1987) by Gill Langley (PhD). STUDIES OF VEGANS Of course, a vegan diet does not comprise a single plant source of protein, but rather a well-balanced mixture of foods, so that vegans need not force themselves to consume 450g rice each day! What levels of protein intake have been measured in studies of vegans, and how do these compare with those found in vegetarians and omnivores? There have now been several such surveys, extending back to 1954. In 1967 Ellis and Mumford (13) reviewed several early studies and found that vegans took 10-11% of their daily energy intake in the form of protein, compared with 11-12% in the case of vegetarians. In 1966 Hardinge et al. (4) calculated that vegan men and women achieved their recommended daily allowances of all essential amino acids and that the pattern of their amino acid intake quite closely resembled that of the protein in human milk, while that of vegetarians and omnivores (with generous intakes of animal proteins) was more similar to the amino acid pattern of cow's milk. In 1981, Abdulla and co-workers (15) used the duplicate portion sampling technique to measure, among other nutrients, protein intakes in six healthy Swedish middle-aged vegans whose diet was deliberately somewhat restricted. Protein intake was 10% of total energy, compared with 12% for Swedish omnivores of similar age. ALTHOUGH ENERGY CONSUMPTION IN THIS VEGAN COMMUNITY WAS LOW, THEIR INTAKE OF ALL ESSENTIAL AMINO ACIDS WAS, AT THE MINIMUM, ALMOST *DOUBLE* THE RECOMMENDATIONS OF THE US NATIONAL ACADEMY OF SCIENCES, AND MORE THAN DOUBLE THE WHO RECOMMENDATIONS. THIS WAS DESPITE THE FACT THAT THESE SUBJECTS DELIBERATELY SUPPRESSED THEIR PROTEIN INTAKE IN THE BELIEF THAT TOO MUCH PROTEIN IS DELETERIOUS TO HEALTH. The protein intake of 22 British vegans was compared with age- and sex-matched omnivores and the mean values found to be slightly lower (16). Lockie and colleagues (17) found from their study of male and female vegans, vegetarians and omnivores that the mean protein intake of the 10 vegans was somewhat lower than that of omnivores and vegetarians, and the same was true of a survey published in 1987 (18) comparing 11 vegans with 11 omnivores. A dietary analysis reported in 1986 (19) similarly showed that a sample of 18 vegans had protein intakes lower than those of omnivores. Interestingly, THIS STUDY ALSO SUGGESTED THAT ADULTS ARE ABLE TO SYNTHESIZE THE AMINO ACID TAURINE FROM OTHER AMINO ACIDS IN THE DIET, SINCE THE LEVEL OF TAURINE IN THE PLASMA AND BREAST MILK OF VEGAN SUBJECTS WAS ADEQUATE - - EVEN THOUGH TAURINE IS NOT PRESENT IN PLANT FOODS. A high-protein diet can adversely affect calcium balance in the body, so that the less excessive intake in a vegan diet facilitates the absorption of calcium - - a significant factor in preventing osteoporosis, which may be less prevalent in vegans and vegetarians. This is discussed in some detail in section 5 (Minerals). STUDIES SHOW THAT THE PROTEIN INTAKE OF VEGANS, EXPRESSED AS A PERCENTAGE OF ENERGY CONSUMED EACH DAY, IS CLOSE TO LEVELS SUGGESTED BY WHO AND NACNE AND ALTHOUGH IT IS SIMILAR TO THAT OF VEGETARIANS AND OMNIVORES, THE LATTER TWO GROUPS EAT MORE PROTEIN THAN GUIDELINES RECOMMEND. (13) PROC. NUTR. SOC., 1967, 26:205. (4) AM. J. CLIN. NUTR., 1974, 27:1231. (14) J. AM. DIET. ASS., 1966, 48:25. (15) AM. J. CLIN. NUTR., 1981, 34:2464. (16) HUM. NUTR.: APPL. NUTR., 1984, 38A:345 (17) J. ROY. COLL. GEN. PRACT., 1985, 35:333. (18) HUM. NUTR.: APPL. NUTR., 1987, 41A:204. (19) BR. J. NUTR., 1986, 56:17. Gill Langley's book is also very useful for lacto- vegetarians as well, since many of the same issues and nutritional needs of vegans apply to all vegetarians. Also, the comparison between vegans and lacto-vegetarians is useful information for all vegetarians. Really, this book is a must for every vegetarian who wishes to get informed about vegetarian nutrition and have plenty of references to primary sources to further research or peruse on one's own. You can buy copies from: The Vegan Society Ltd 7 Battle Road St Leonards-on-Sea East Sussex TN37 7AA A more comprehensive vegetarian mail-order house has recently been established by PAWS (The Progressive Animal Welfare Society). They actually have a store in Seattle: The PAWS Store 8503 Greenwood Ave. N. Seattle, WA 98103 U.S.A. Phone/Fax (206) 782-1700 Write and ask for their extensive catalogue of vegetarian books and pro-animal book, vegetarian vitamins, vegetarian sandals, etc. Alternatively, you can also mail-order for a copy of Gill :Langley's book from the following pro-vegetarian organization that is also worth supporting: THE AMERICAN VEGAN SOCIETY 501 OLD HARDING HIGHWAY MALAGA, NJ 08328 U.S.A. Phone: (609) 694-2887 Hope this helps, Ted Altar