Low-protein diet

Last updated

A low-protein diet is a diet in which people decrease their intake of protein. A low-protein diet is used as a therapy for inherited metabolic disorders, such as phenylketonuria and homocystinuria, and can also be used to treat kidney or liver disease. Low protein consumption appears to reduce the risk of bone breakage, presumably through changes in calcium homeostasis. [1] Consequently, there is no uniform definition of what constitutes low-protein, because the amount and composition of protein for an individual with phenylketonuria would differ substantially from one with homocystinuria or tyrosinemia. [2]

Contents

History

By studying the composition of food in the local population in Germany, Carl von Voit established a standard of 118 grams of protein per day. Russell Henry Chittenden showed that less than half that amount was needed to maintain good health. [3]

Protein requirement

The daily requirement for humans to remain in nitrogen balance is relatively small. The median human adult requirement for good quality protein is approximately 0.65 gram per kilogram body weight per day and the 97.5 percentile is 0.83 grams per kilogram body weight per day. [4] Children require more protein, depending on the growth phase. A 70 kg adult human who was in the middle of the range would require approximately 45 grams of protein per day to be in nitrogen balance. This would represent less than 10% of kilocalories in a notional 2,200 kilocalorie ration. William Cumming Rose and his team studied the essential amino acids, helping to define minimum amounts needed for normal health. For adults, the recommended minimum amounts of each essential amino acid varies from 4 to 39 milligrams per kilogram of body weight per day. To be of good quality, protein only needs to come from a wide variety of foods; there is neither a need to mix animal and plant food together nor a need to complement specific plant foods, such as rice and beans. [5] The notion that such specific combinations of plant protein need to be made to give good quality protein stems from the book Diet for a Small Planet . Plant protein is often described as incomplete, suggesting that they lack one or more of the essential amino acids. Apart from rare examples, such as Taro, [5] [6] each plant provides an amount of all the essential amino acids. However, the relative abundance of the essential amino acids is more variable in plants than that found in animals, which tend to be very similar in essential amino acid abundance, and this has led to the misconception that plant proteins are deficient in some way.

Low-protein vs calorie restriction

Calorie restriction has been demonstrated to increase the life span and decrease the age-associated morbidity of many experimental animals. Increases in longevity or reductions in age-associated morbidity have also been shown for model systems where protein or specific amino acids have been reduced. In particular, experiments in model systems in rats, mice, and Drosophila fruit flies have shown increases in life-span with reduced protein intake comparable to that for calorie restriction. [7] [8] Restriction of the amino acid methionine, which is required to initiate protein synthesis, is sufficient to extend lifespan. [9] [10] [11] Restriction of the branched-chain amino acids is sufficient to extend the lifespan of Drosophila fruit flies and male mice. [12] [8]

Some of the most dramatic effects of calorie restriction are on metabolic health, promoting leanness, decreasing blood sugar and increasing insulin sensitivity. [13] Low-protein diets mimic many of the effects of calorie restriction but may engage different metabolic mechanisms. [14] Low protein diets rapidly reduce fat and restores normal insulin sensitivity to diet-induced obese mice. [15] Specifically restricting consumption of the three branched-chain amino acids leucine, isoleucine and valine is sufficient to promote leanness and improve regulation of blood glucose. [16] A recent randomized-controlled clinical trial showed that protein restriction (PR) improves multiple markers of metabolic health, such as reducing adiposity and improving insulin sensitivity. [17]

The diets of humans living in some of the Blue Zones, regions of enhanced numbers of centenarians and reduced age-associated morbidity, contain less than 10% of energy from protein, [18] although reports on all the Blue Zones are not available. None of the diets in these regions is completely based on plants, but plants form the bulk of the food eaten. [19] Although it has been speculated that some of these populations are under calorie restriction, this is contentious as their smaller size is consistent with the lower food consumption. [20]

Low-protein and osteoporosis

The effect of protein on osteoporosis and risk of bone fracture is complex. Calcium loss from bone occurs at protein intake below requirement when individuals are in negative protein balance, suggesting that too little protein is dangerous for bone health. [21] IGF-1, which contributes to muscle growth, also contributes to bone growth, and IGF-1 is modulated by protein intake. [22]

However, at high protein levels, a net loss of calcium may occur through the urine in neutralizing the acid formed from the deamination and subsequent metabolism of methionine and cysteine. Large prospective cohort studies have shown a slight increase in risk of bone fracture when the quintile of highest protein consumption is compared to the quintile of lowest protein consumption. [1] In these studies, the trend is also seen for animal protein but not plant protein, but the individuals differ substantially in animal protein intake and very little in plant protein intake. As protein consumption increases, calcium uptake from the gut is enhanced. [1] [21] Normal increases in calcium uptake occur with increased protein in the range 0.8 grams to 1.5 grams of protein per kilogram body weight per day. However, calcium uptake from the gut does not compensate for calcium loss in the urine at protein consumption of 2 grams of protein per kilogram of body weight. Calcium is not the only ion that neutralizes the sulphate from protein metabolism, and overall buffering and renal acid load also includes anions such as bicarbonate, organic ions, phosphorus and chloride as well as cations such as ammonium, titrateable acid, magnesium, potassium and sodium. [23]

The study of potential renal acid load (PRAL) suggests that increased consumption of fruits, vegetables and cooked legumes increases the ability of the body to buffer acid from protein metabolism, because they contribute to a base forming potential in the body due to their relative concentrations of proteins and ions. However, not all plant material is base forming, for example, nuts, grains and grain products add to the acid load. [21] [23] [24]

See also

Related Research Articles

<span class="mw-page-title-main">Fat</span> Esters of fatty acid or triglycerides

In nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such compounds, most commonly those that occur in living beings or in food.

<span class="mw-page-title-main">Isoleucine</span> Chemical compound

Isoleucine (symbol Ile or I) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated −NH+3 form under biological conditions), an α-carboxylic acid group (which is in the deprotonated −COO− form under biological conditions), and a hydrocarbon side chain with a branch (a central carbon atom bound to three other carbon atoms). It is classified as a non-polar, uncharged (at physiological pH), branched-chain, aliphatic amino acid. It is essential in humans, meaning the body cannot synthesize it. Essential amino acids are necessary in the human diet. In plants isoleucine can be synthesized from threonine and methionine. In plants and bacteria, isoleucine is synthesized from pyruvate employing leucine biosynthesis enzymes. It is encoded by the codons AUU, AUC, and AUA.

<span class="mw-page-title-main">Leucine</span> Chemical compound

Leucine (symbol Leu or L) is an essential amino acid that is used in the biosynthesis of proteins. Leucine is an α-amino acid, meaning it contains an α-amino group (which is in the protonated −NH3+ form under biological conditions), an α-carboxylic acid group (which is in the deprotonated −COO− form under biological conditions), and a side chain isobutyl group, making it a non-polar aliphatic amino acid. It is essential in humans, meaning the body cannot synthesize it: it must be obtained from the diet. Human dietary sources are foods that contain protein, such as meats, dairy products, soy products, and beans and other legumes. It is encoded by the codons UUA, UUG, CUU, CUC, CUA, and CUG. Leucine is named after the Greek word for "white": λευκός (leukós, "white"), after its common appearance as a white powder, a property it shares with many other amino acids.

Valine (symbol Val or V) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated −NH3+ form under biological conditions), an α-carboxylic acid group (which is in the deprotonated −COO− form under biological conditions), and a side chain isopropyl group, making it a non-polar aliphatic amino acid. Valine is essential in humans, meaning the body cannot synthesize it; it must be obtained from dietary sources which are foods that contain proteins, such as meats, dairy products, soy products, beans and legumes. It is encoded by all codons starting with GU (GUU, GUC, GUA, and GUG).

<span class="mw-page-title-main">Dietary fiber</span> Portion of plant-derived food that cannot be completely digested

Dietary fiber or roughage is the portion of plant-derived food that cannot be completely broken down by human digestive enzymes. Dietary fibers are diverse in chemical composition and can be grouped generally by their solubility, viscosity and fermentability which affect how fibers are processed in the body. Dietary fiber has two main subtypes: soluble fiber and insoluble fiber which are components of plant-based foods such as legumes, whole grains, cereals, vegetables, fruits, and nuts or seeds. A diet high in regular fiber consumption is generally associated with supporting health and lowering the risk of several diseases. Dietary fiber consists of non-starch polysaccharides and other plant components such as cellulose, resistant starch, resistant dextrins, inulin, lignins, chitins, pectins, beta-glucans, and oligosaccharides.

A nutrient is a substance used by an organism to survive, grow and reproduce. The requirement for dietary nutrient intake applies to animals, plants, fungi and protists. Nutrients can be incorporated into cells for metabolic purposes or excreted by cells to create non-cellular structures such as hair, scales, feathers, or exoskeletons. Some nutrients can be metabolically converted into smaller molecules in the process of releasing energy such as for carbohydrates, lipids, proteins and fermentation products leading to end-products of water and carbon dioxide. All organisms require water. Essential nutrients for animals are the energy sources, some of the amino acids that are combined to create proteins, a subset of fatty acids, vitamins and certain minerals. Plants require more diverse minerals absorbed through roots, plus carbon dioxide and oxygen absorbed through leaves. Fungi live on dead or living organic matter and meet nutrient needs from their host.

<span class="mw-page-title-main">Human nutrition</span> Nutrients supporting human health

Human nutrition deals with the provision of essential nutrients in food that are necessary to support human life and good health. Poor nutrition is a chronic problem often linked to poverty, food security, or a poor understanding of nutritional requirements. Malnutrition and its consequences are large contributors to deaths, physical deformities, and disabilities worldwide. Good nutrition is necessary for children to grow physically and mentally, and for normal human biological development.

An essential amino acid, or indispensable amino acid, is an amino acid that cannot be synthesized from scratch by the organism fast enough to supply its demand, and must therefore come from the diet. Of the 21 amino acids common to all life forms, the nine amino acids humans cannot synthesize are valine, isoleucine, leucine, methionine, phenylalanine, tryptophan, threonine, histidine, and lysine.

<span class="mw-page-title-main">Dietary supplement</span> Product providing additional nutrients

A dietary supplement is a manufactured product intended to supplement a person's diet by taking a pill, capsule, tablet, powder, or liquid. A supplement can provide nutrients either extracted from food sources, or that are synthetic. The classes of nutrient compounds in supplements include vitamins, minerals, fiber, fatty acids, and amino acids. Dietary supplements can also contain substances that have not been confirmed as being essential to life, and so are not nutrients per se, but are marketed as having a beneficial biological effect, such as plant pigments or polyphenols. Animals can also be a source of supplement ingredients, such as collagen from chickens or fish for example. These are also sold individually and in combination, and may be combined with nutrient ingredients. The European Commission has also established harmonized rules to help insure that food supplements are safe and appropriately labeled.

<span class="mw-page-title-main">Low-carbohydrate diet</span> Diets restricting carbohydrate consumption

Low-carbohydrate diets restrict carbohydrate consumption relative to the average diet. Foods high in carbohydrates are limited, and replaced with foods containing a higher percentage of fat and protein, as well as low carbohydrate foods.

<span class="mw-page-title-main">Vegetarian nutrition</span> Nutritional and human health aspects of vegetarian diets

Vegetarian nutrition is the set of health-related challenges and advantages of vegetarian diets.

<span class="mw-page-title-main">Cat food</span> Food for consumption by cats

Cat food is food specifically formulated and designed for consumption by cats. As obligate carnivores, cats have specific requirements for their dietary nutrients, namely nutrients found only in meat or synthesized, such as taurine and Vitamin A. Certain nutrients, including many vitamins and amino acids, are degraded by the temperatures, pressures and chemical treatments used during manufacture, and hence must be added after manufacture to avoid nutritional deficiency. Cat food is typically sold as dry kibble, or as wet food in cans and pouches.

Calorie restriction is a dietary regimen that reduces the energy intake from foods and beverages without incurring malnutrition. The possible effect of calorie restriction on body weight management, longevity, and aging-associated diseases has been an active area of research.

<span class="mw-page-title-main">Branched-chain amino acid</span> Amino acid with a branched carbon chain

A branched-chain amino acid (BCAA) is an amino acid having an aliphatic side-chain with a branch. Among the proteinogenic amino acids, there are three BCAAs: leucine, isoleucine, and valine. Non-proteinogenic BCAAs include 2-aminoisobutyric acid and alloisoleucine.

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.

<span class="mw-page-title-main">Protein (nutrient)</span> Nutrient for the human body

Proteins are essential nutrients for the human body. They are one of the building blocks of body tissue and can also serve as a fuel source. As a fuel, proteins provide as much energy density as carbohydrates: 4 kcal per gram; in contrast, lipids provide 9 kcal per gram. The most important aspect and defining characteristic of protein from a nutritional standpoint is its amino acid composition.

<span class="mw-page-title-main">Vegan nutrition</span> Nutritional and human health aspects of vegan diets

Vegan nutrition refers to the nutritional and human health aspects of vegan diets. A well-planned vegan diet is suitable to meet all recommendations for nutrients in every stage of human life. Vegan diets tend to be higher in dietary fiber, magnesium, folic acid, vitamin C, vitamin E, and phytochemicals; and lower in calories, saturated fat, iron, cholesterol, long-chain omega-3 fatty acids, vitamin D, calcium, zinc, and vitamin B12.

The human skeletal system is a complex organ in constant equilibrium with the rest of the body. In addition to supporting and giving structure to the body, a bone is the major reservoir for many minerals and compounds essential for maintaining a healthy pH balance. The deterioration of the body with age renders the elderly particularly susceptible to and affected by poor bone health. Illnesses like osteoporosis, characterized by weakening of the bone's structural matrix, increases the risk of hip-fractures and other life-changing secondary symptoms. In 2010, over 258,000 people aged 65 and older were admitted to the hospital for hip fractures. Incidence of hip fractures is expected to rise by 12% in America, with a projected 289,000 admissions in the year 2030. Other sources estimate up to 1.5 million Americans will have an osteoporotic-related fracture each year. The cost of treating these people is also enormous, in 1991 Medicare spent an estimated $2.9 billion for treatment and out-patient care of hip fractures, this number can only be expected to rise.

<span class="mw-page-title-main">Vegetarian and vegan dog diet</span> Adequate meat-free or animal-free nutrition

As in the human practice of veganism, vegan dog foods are those formulated with the exclusion of ingredients that contain or were processed with any part of an animal, or any animal byproduct. Vegan dog food may incorporate the use of fruits, vegetables, cereals, legumes including soya, nuts, vegetable oils, as well as any other non-animal based foods.

References

  1. 1 2 3 Feskanich, Diane; Willett, Walter C.; Stampfer, Meir J.; Colditz, Graham A. (1996). "Protein Consumption and Bone Fractures in Women". American Journal of Epidemiology. 143 (5): 472–9. doi: 10.1093/oxfordjournals.aje.a008767 . PMID   8610662.
  2. ↑ Zea-Rey, Alexandra V.; Cruz-Camino, Héctor; Vazquez-Cantu, Diana L.; Gutiérrez-García, Valeria M.; Santos-Guzmán, Jesús; Cantú-Reyna, Consuelo (27 November 2017). "The Incidence of Transient Neonatal Tyrosinemia Within a Mexican Population" (PDF). Journal of Inborn Errors of Metabolism and Screening. 5: 232640981774423. doi:10.1177/2326409817744230.
  3. ↑ Lewis, Howard B. (1944). "Russell Henry Chittenden (1856–1943)". Journal of Biological Chemistry. 153 (2): 339–42. doi: 10.1016/S0021-9258(18)71975-3 .
  4. ↑ Rand, William M; Pellett, Peter L; Young, Vernon R (2003). "Meta-analysis of nitrogen balance studies for estimating protein requirements in healthy adults". The American Journal of Clinical Nutrition. 77 (1): 109–27. doi: 10.1093/ajcn/77.1.109 . PMID   12499330.
  5. 1 2 McDougall, J. (2002). "Plant Foods Have a Complete Amino Acid Composition". Circulation. 105 (25): e197, author reply e197. doi: 10.1161/01.CIR.0000018905.97677.1F . PMID   12082008.
  6. ↑ "SELF Nutrition Data | Food Facts, Information & Calorie Calculator".
  7. ↑ Solon-Biet, Samantha M.; McMahon, Aisling C.; Ballard, J. William O.; Ruohonen, Kari; Wu, Lindsay E.; Cogger, Victoria C.; Warren, Alessandra; Huang, Xin; Pichaud, Nicolas; Melvin, Richard G.; Gokarn, Rahul (2014-03-04). "The ratio of macronutrients, not caloric intake, dictates cardiometabolic health, aging, and longevity in ad libitum-fed mice". Cell Metabolism. 19 (3): 418–430. doi:10.1016/j.cmet.2014.02.009. ISSN   1932-7420. PMC   5087279 . PMID   24606899.
  8. 1 2 Richardson, Nicole E.; Konon, Elizabeth N.; Schuster, Haley S.; Mitchell, Alexis T.; Boyle, Colin; Rodgers, Allison C.; Finke, Megan; Haider, Lexington R.; Yu, Deyang; Flores, Victoria; Pak, Heidi H. (January 2021). "Lifelong restriction of dietary branched-chain amino acids has sex-specific benefits for frailty and life span in mice". Nature Aging. 1 (1): 73–86. doi:10.1038/s43587-020-00006-2. ISSN   2662-8465. PMC   8009080 . PMID   33796866.
  9. ↑ Orentreich, Norman; Matias, Jonathan R.; DeFelice, Anthony; Zimmerman, Jay A. (1993). "Low Methionine Ingestion by Rats Extends Life Span". The Journal of Nutrition. 123 (2): 269–74. doi:10.1093/jn/123.2.269 (inactive 1 November 2024). PMID   8429371.{{cite journal}}: CS1 maint: DOI inactive as of November 2024 (link)
  10. ↑ Grandison, Richard C.; Piper, Matthew D. W.; Partridge, Linda (2009). "Amino-acid imbalance explains extension of lifespan by dietary restriction in Drosophila". Nature. 462 (7276): 1061–4. Bibcode:2009Natur.462.1061G. doi:10.1038/nature08619. PMC   2798000 . PMID   19956092.
  11. ↑ Brind, Joel; Malloy, Virginia; Augie, Ines; Caliendo, Nicholas; Vogelman, Joseph H; Zimmerman, Jay A.; Orentreich, Norman (2011). "Dietary glycine supplementation mimics lifespan extension by dietary methionine restriction in Fisher 344 rats". The FASEB Journal. 25 (Meeting Abstract Supplement): 528.2. doi: 10.1096/fasebj.25.1_supplement.528.2 . S2CID   83535621.
  12. ↑ Juricic, Paula; Grönke, Sebastian; Partridge, Linda (1 January 2020). "Branched-Chain Amino Acids Have Equivalent Effects to Other Essential Amino Acids on Lifespan and Aging-Related Traits in Drosophila". The Journals of Gerontology. Series A, Biological Sciences and Medical Sciences. 75 (1): 24–31. doi:10.1093/gerona/glz080. ISSN   1758-535X. PMC   6909895 . PMID   30891588.
  13. ↑ Fontana, Luigi; Partridge, Linda (2015-03-26). "Promoting health and longevity through diet: from model organisms to humans". Cell. 161 (1): 106–118. doi:10.1016/j.cell.2015.02.020. ISSN   1097-4172. PMC   4547605 . PMID   25815989.
  14. ↑ Solon-Biet, Samantha M.; Mitchell, Sarah J.; Coogan, Sean C. P.; Cogger, Victoria C.; Gokarn, Rahul; McMahon, Aisling C.; Raubenheimer, David; de Cabo, Rafael; Simpson, Stephen J. (2015-06-16). "Dietary Protein to Carbohydrate Ratio and Caloric Restriction: Comparing Metabolic Outcomes in Mice". Cell Reports. 11 (10): 1529–1534. doi:10.1016/j.celrep.2015.05.007. ISSN   2211-1247. PMC   4472496 . PMID   26027933.
  15. ↑ Cummings, Nicole E.; Williams, Elizabeth M.; Kasza, Ildiko; Konon, Elizabeth N.; Schaid, Michael D.; Schmidt, Brian A.; Poudel, Chetan; Sherman, Dawn S.; Yu, Deyang (2017-12-19). "Restoration of metabolic health by decreased consumption of branched-chain amino acids". The Journal of Physiology. 596 (4): 623–645. doi:10.1113/JP275075. ISSN   1469-7793. PMC   5813603 . PMID   29266268.
  16. ↑ Fontana, Luigi; Cummings, Nicole E.; Arriola Apelo, Sebastian I.; Neuman, Joshua C.; Kasza, Ildiko; Schmidt, Brian A.; Cava, Edda; Spelta, Francesco; Tosti, Valeria (2016-06-21). "Decreased Consumption of Branched-Chain Amino Acids Improves Metabolic Health". Cell Reports. 16 (2): 520–30. doi:10.1016/j.celrep.2016.05.092. ISSN   2211-1247. PMC   4947548 . PMID   27346343.
  17. ↑ Ferraz-Bannitz, Rafael (2022-06-28). "Dietary Protein Restriction Improves Metabolic Dysfunction in Patients with Metabolic Syndrome in a Randomized, Controlled Trial". Nutrients. 14 (13): 2670. doi: 10.3390/nu14132670 . PMC   9268415 . PMID   35807851.
  18. ↑ Willcox, B. J.; Willcox, D. C.; Todoriki, H.; Fujiyoshi, A.; Yano, K.; He, Q.; Curb, J. D.; Suzuki, M. (2007). "Caloric Restriction, the Traditional Okinawan Diet, and Healthy Aging: The Diet of the World's Longest-Lived People and Its Potential Impact on Morbidity and Life Span". Annals of the New York Academy of Sciences. 1114 (1): 434–55. Bibcode:2007NYASA1114..434W. doi:10.1196/annals.1396.037. PMID   17986602. S2CID   8145691.
  19. ↑ Pes, G.M.; Tolu, F.; Poulain, M.; Errigo, A.; Masala, S.; Pietrobelli, A.; Battistini, N.C.; Maioli, M. (2013). "Lifestyle and nutrition related to male longevity in Sardinia: An ecological study". Nutrition, Metabolism and Cardiovascular Diseases. 23 (3): 212–9. doi:10.1016/j.numecd.2011.05.004. PMID   21958760.
  20. ↑ Keys, Ancel; Kimura, Noboru (1970). "Diets of Middle-Aged Farmers in Japan". The American Journal of Clinical Nutrition. 23 (2): 212–23. doi: 10.1093/ajcn/23.2.212 . PMID   5415568.
  21. 1 2 3 Heaney, Robert P; Layman, Donald K (2008). "Amount and type of protein influences bone health". The American Journal of Clinical Nutrition. 87 (5): 1567S–1570S. doi: 10.1093/ajcn/87.5.1567S . PMID   18469289.
  22. ↑ Thissen, Jean-Paul; Ketelslegers, Jean-Marie; Underwood, Louis E. (1994). "Nutritional Regulation of the Insulin-Like Growth Factors". Endocrine Reviews. 15 (1): 80–101. doi:10.1210/edrv-15-1-80. PMID   8156941.
  23. 1 2 Remer, Thomas; Manz, Friedrich (1995). "Potential Renal Acid Load of Foods and its Influence on Urine pH". Journal of the American Dietetic Association. 95 (7): 791–7. doi:10.1016/S0002-8223(95)00219-7. PMID   7797810.
  24. ↑ Barzel, Uriel S.; Massey, Linda K. (1998). "Excess Dietary Protein Can Adversely Affect Bone". The Journal of Nutrition. 128 (6): 1051–3. doi: 10.1093/jn/128.6.1051 . PMID   9614169.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.