Complete protein
A complete protein or whole protein is a food source of protein that contains an adequate proportion of each of the nine essential amino acids necessary in the human diet.[1][2][3][4][5]
Amino acid profile
People who eat a varied diet generally do not have to consider the completeness of proteins of single foods. Different protein sources that are each incomplete on their own, typically are complete when combined.[6]
The following table lists the optimal profile of the nine essential amino acids in the human diet, which comprises complete protein, as recommended by the US Institute of Medicine's Food and Nutrition Board. The foodstuffs listed for comparison show the essential amino acid content per unit of the total protein of the food, 100g of spinach, for example, only contains 2.9g of protein (6% Daily Value), and of that protein 1.36% is tryptophan.[2][7](note that the examples have not been corrected for digestibility)
| Essential amino acid | mg/g of protein | percentage of total protein | raw, whole chicken egg[8] | quinoa[9] | raw spinach[10] |
|---|---|---|---|---|---|
| Tryptophan | 7 | 0.7% | 1.33% | 1% | 1.36% |
| Threonine | 27 | 2.7% | 4.42% | 3.2% | 4.27% |
| Isoleucine | 25 | 2.5% | 5.34% | 4.2% | 5.14% |
| Leucine | 55 | 5.5% | 8.65% | 7.3% | 7.8% |
| Lysine | 51 | 5.1% | 7.27% | 6.1% | 6.08% |
| Methionine+Cystine | 25 | 2.5% | 5.18% | 2.7%+1.3% | 1.85%+1.22% |
| Phenylalanine+Tyrosine | 47 | 4.7% | 9.39% | 4.3%+3.6% | 4.51%+3.78% |
| Valine | 32 | 3.2% | 6.83% | 5% | 5.63% |
| Histidine | 18 | 1.8% | 2.45% | 3.1% | 2.24% |
| Total | 287 | 28.7% | 50.86% | 41.8% | 43.88% |
Total adult daily intake
The second column in the following table shows the amino acid requirements of adults as recommended by the World Health Organization[11] calculated for a 62 kg (137 lb) adult. Recommended Daily Intake is based on 2,000 kilocalories (8,400 kJ) per day,[12] which could be appropriate for a 70 kg (150 lb) adult.
| Essential amino acid | Required mg/day for a 62 kg (137 lb) adult |
|---|---|
| Tryptophan | 248 |
| Threonine | 930 |
| Isoleucine | 1240 |
| Leucine | 2418 |
| Lysine | 1860 |
| Methionine+Cystine | 930 |
| Phenylalanine+Tyrosine | 1550 |
| Valine | 1612 |
| Histidine | 620 |
| Total | 11,408 milligrams (11.408 g) |
| Total Protein | 46 to 56 grams (46,000 to 56,000 mg) |
Concept
In a plant-based diet there is the perceived issue of amino acid content of various individual foods. A satisfying diet however, will include minimum requirements of all essential amino acids.
In addition to grains, such as corn, rice, or wheat, vegetable protein also occurs in legumes, which include beans and peanuts. Grains tend to be deficient in tryptophan and lysine, whereas legumes lack methionine Thus a meal combining grains and legumes such as the Mexican peasant dish of corn tortillas and refried beans is basically complete in amino acid content.
— Stanley E. Manahan, General Applied Chemistry 1978,82 , page 474
See also
References
- ^ "Protein in diet". Medline Plus Medical Encyclopedia. U.S. National Library of Medicine and National Institute of Health. September 2, 2003. Retrieved 2006-10-28.
- ^ a b Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. Food and Nutrition Board of Institute of Medicine, National Academies Press. 2005. p. 691. doi:10.17226/10490. ISBN 978-0-309-08525-0.
- ^ "All About the Protein Foods Group". US Department of Agriculture. 3 November 2017. Retrieved 20 May 2018.
- ^ Mariotti, François; Gardner, Christopher D. (Nov 2019). "Dietary Protein and Amino Acids in Vegetarian Diets—A Review". Nutrients. 11 (11): 2661. doi:10.3390/nu11112661. PMC 6893534. PMID 31690027.
- ^ Young, VR; Pellett, PL (May 1994). "Plant proteins in relation to human protein and amino acid nutrition". The American Journal of Clinical Nutrition. 59 (5 Suppl): 1203S–1212S. doi:10.1093/ajcn/59.5.1203S. PMID 8172124.
- ^ "What's a Complete Protein and Should You Care?". Cleveland Clinic. Retrieved 2024-04-19.
- ^ "Protein quality". Conde Nast, Nutritiondata.com. 2018. Retrieved 13 April 2020.
- ^ "Egg, whole, raw, fresh, nutrition facts per 100 grams". Conde Nast, Nutritiondata.com. 2018. Retrieved 13 April 2020.
- ^ "Quinoa, cooked, nutrition facts per 100 grams". Conde Nast, Nutritiondata.com. 2018. Retrieved 13 April 2020.
- ^ "Spinach, raw, nutrition facts per 100 grams". Conde Nast, Nutritiondata.com. 2018. Retrieved 13 April 2020.
- ^ "Protein and Amino Acid Requirements in Human Nutrition" (PDF). World Health Organization. 2007. Retrieved January 21, 2021.
- ^ "Guidance for Industry: A Food Labeling Guide". U.S. Food & Drug Administration. US FDA. Archived from the original on 2017-10-31. Retrieved 14 January 2017.