{"url":"https://whatshealthyandwhy.com/protein-intake/how-much-protein-do-you-need","path":"/protein-intake/how-much-protein-do-you-need","alternates":{"json":"https://whatshealthyandwhy.com/api/articles/protein-intake/how-much-protein-do-you-need.json","markdown":"https://whatshealthyandwhy.com/protein-intake/how-much-protein-do-you-need.md"},"topic":{"slug":"protein-intake","name":"Protein Intake","url":"https://whatshealthyandwhy.com/protein-intake"},"slug":"how-much-protein-do-you-need","order":1,"title":"How Much Protein Do You Need?","question":"How much protein do you really need, and from which sources?","answer":"Most adults need at least 0.8 g per kg of body weight; older adults and lifters likely do better at 1.0 to 1.6 g/kg.","description":"How much protein adults, older people and lifters need, plant versus animal sources, whether high intakes harm kidneys or bones, and how to spread it.","confidence":3,"confidenceNote":"Trial meta-analyses support the muscle and kidney-safety points, but the targets for older adults and the plant versus animal comparison rest mostly on observational data.","evidenceSummary":{"rctCount":1,"observationalCount":3,"metaAnalysisCount":4,"totalParticipants":"715,128 (pooled cohorts)","replicated":true,"newestStudyYear":2020},"category":{"categoryTitle":"What's Good For You","categorySlug":"good-for-you","subcategoryName":"Foods & Drinks","subcategorySlug":"foods","url":"https://whatshealthyandwhy.com/explore/good-for-you/foods"},"actions":["Baseline: 0.8 g/kg of body weight is the minimum (56 g for a 70 kg adult); aim for 1.0–1.2+ g/kg if over 65, training regularly or recovering from illness [1][2].","Spread protein over the day: about 30 g at each of three meals raised muscle protein synthesis more than a lopsided day, and older adults need more per meal [5][6].","Lean toward plant proteins (beans, lentils, tofu, nuts, grains), with fish, eggs, dairy and poultry in support: swapping red and processed meat for plant protein goes with lower mortality [7][8]."],"cautions":["If you have kidney disease, especially an eGFR below 30 and not on dialysis, you may need to limit protein. Follow your nephrologist's plan rather than these general numbers [2].","This article covers healthy adults. Needs differ in pregnancy, childhood, liver disease and other illnesses, so ask a clinician or dietitian."],"simpleText":"Most adults need at least 0.8 g of protein per kg of body weight a day (56 g for a 70 kg adult), but that is a floor, not a target [1]. Older adults and people who lift weights probably do better at 1.0 to 1.6 g/kg [2][3]. In healthy people, higher intakes did not harm kidney function in trials [4]. Favor plant proteins and spread protein across your meals.","mediumText":"How it works\n\nWhere 0.8 comes from. The official recommended allowance was set as the smallest amount that prevents a loss of body nitrogen, not as the best amount. The accepted range for protein is 10% to 35% of calories, and even the bottom of that range sits above the allowance [1].\n\nOlder adults. An expert group recommends at least 1.0 to 1.2 g/kg a day for people over 65, at least 1.2 g/kg if they exercise, and 1.2 to 1.5 g/kg for those with acute or chronic illness [2]. Among 2,066 adults aged 70 to 79, those in the top fifth for protein lost about 40% less lean mass over 3 years than those in the bottom fifth [9].\n\nLifters. In 49 trials of resistance training, protein supplements added a little muscle and strength. Gains leveled off at about 1.6 g/kg of total daily protein, with the upper end of the estimate at 2.2 g/kg [3].\n\nSpreading it out. Eating about 30 g at each of three meals raised 24-hour muscle protein synthesis by 25% compared with a day that put 63 g at dinner [5]. Older men needed about 0.40 g/kg in one meal to get the maximum response, versus 0.24 g/kg for young men [6]. For a 70 kg older adult, that is about 28 g.\n\nWhich protein. Pooling 31 cohorts, plant protein went with lower all-cause and cardiovascular mortality, and an extra 3% of calories from plant protein with 5% lower death risk [7]. In two big US cohorts, replacing 3% of calories from processed red meat with plant protein was linked to 34% lower mortality [8].\n\nWhat it looks like. Per 100 g cooked, lentils and black beans give about 9 g of protein, a hard-boiled egg 12.6 g, salmon 22 to 25 g and ground beef 26 g. A cup of cooked lentils (198 g) provides about 18 g [10].\n\nSafety. In 28 trials, higher-protein diets did not reduce kidney filtration in healthy adults [4]. Higher intakes also showed no harm to bone and a small gain at the lumbar spine [11].\n\nRelated reading: sarcopenia, whey protein, pea protein and beans and legumes.","deepText":"The evidence in detail\n\nMuscle and strength. Morton and colleagues pooled 49 trials (1,863 participants) of resistance training lasting at least six weeks. Protein supplementation increased one-repetition-maximum strength by 2.49 kg (95% CI 0.64 to 4.33), fat-free mass by 0.30 kg (0.09 to 0.52) and muscle fiber area by 310 square micrometers. The benefit shrank with age and was larger in trained people. A break-point analysis put the plateau at 1.62 g/kg a day (95% CI 1.03 to 2.20). Authors reported ties to the US National Dairy Council and a sports-supplement maker [3].\n\nOlder adults. The PROT-AGE group's recommendations are a consensus statement, not a trial; it notes evidence on quality and timing is insufficient for firm advice [2]. The Health ABC cohort tracked 2,066 adults aged 70 to 79 with DXA scans: the top quintile of protein lost 0.50 kg of lean mass versus 0.88 kg in the bottom quintile, a pattern that held after adjusting for fat mass change but is observational [9]. Moore and colleagues re-analyzed lab studies of healthy men (about 71 and 22 years old): muscle protein synthesis plateaued at 0.40 g/kg per meal in older men versus 0.24 in younger (p = 0.055), and these were single-meal measures, not long-term outcomes [6]. Mamerow's crossover trial in 8 adults compared 7 days of even protein (about 30 g per meal) with a skewed pattern (11, 16 and 63 g); even eating gave 25% higher 24-hour muscle protein synthesis. It was tiny, short, measured synthesis rather than muscle size, and the authors reported ties to beef-industry groups [5].\n\nSource and mortality. Naghshi's meta-analysis of 31 cohorts (715,128 people, 113,039 deaths) found total protein was linked to lower all-cause mortality (pooled effect 0.94), plant protein to lower all-cause (0.92) and cardiovascular mortality (0.88), and animal protein was not clearly related to cardiovascular or cancer mortality [7]. In the Nurses' Health Study and Health Professionals Follow-up Study (131,342 people), animal protein was associated with higher cardiovascular mortality (hazard ratio 1.08 per 10% of energy) and plant protein with lower all-cause mortality (0.90 per 3% of energy), mostly in people with at least one unhealthy lifestyle factor; substituting plant protein for processed red meat gave 0.66 [8].\n\nConflicting evidence. Levine and colleagues found that adults aged 50 to 65 reporting high protein intake had 75% higher mortality and a fourfold higher cancer death risk over 18 years, attenuated if the protein was plant-derived, whereas in those over 65 high intake went with lower mortality. Mouse experiments supported a growth-factor mechanism. The senior author holds equity in a company that develops medical foods [12]. These results oppose Naghshi's pooled finding and illustrate how much the answer depends on age and source.\n\nKidneys and bones. Devries and colleagues pooled 28 trials (1,358 healthy adults) comparing high protein (at least 1.5 g/kg or 20% of energy) with lower protein. Post-intervention filtration rate was trivially higher with more protein (standardized difference 0.19), and its change did not differ (0.11, 95% CI -0.05 to 0.27). Risk of selection bias was unclear and the data do not cover people with kidney disease [4]. A review of 16 trials and 20 cohorts found moderate evidence for a small lumbar-spine bone density gain (0.52%) with more protein and no effect at hip or whole body, with no adverse effects [11].\n\nBottom line (confidence 3 of 5). The floor is 0.8 g/kg. For lifters and older adults, 1.0 to 1.6 g/kg is better supported than the floor, and in healthy people higher intakes appear safe for kidneys and bones. Plant-leaning sources look best in cohorts, but the evidence is observational.","deepTruncated":false,"references":[{"id":"1","title":"Optimizing Protein Intake in Adults: Interpretation and Application of the Recommended Dietary Allowance Compared with the Acceptable Macronutrient Distribution Range","authors":"Wolfe RR, Cifelli AM, Kostas G, et al.","year":2017,"journal":"Adv Nutr","pmid":"28298271","url":"https://pubmed.ncbi.nlm.nih.gov/28298271/"},{"id":"2","title":"Evidence-based recommendations for optimal dietary protein intake in older people: a position paper from the PROT-AGE Study Group","authors":"Bauer J, Biolo G, Cederholm T, et al.","year":2013,"journal":"J Am Med Dir Assoc","pmid":"23867520","url":"https://pubmed.ncbi.nlm.nih.gov/23867520/"},{"id":"3","title":"A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults","authors":"Morton RW, Murphy KT, McKellar SR, et al.","year":2018,"journal":"Br J Sports Med","pmid":"28698222","url":"https://pubmed.ncbi.nlm.nih.gov/28698222/"},{"id":"4","title":"Changes in Kidney Function Do Not Differ between Healthy Adults Consuming Higher- Compared with Lower- or Normal-Protein Diets: A Systematic Review and Meta-Analysis","authors":"Devries MC, Sithamparapillai A, Brimble KS, et al.","year":2018,"journal":"J Nutr","pmid":"30383278","url":"https://pubmed.ncbi.nlm.nih.gov/30383278/"},{"id":"5","title":"Dietary protein distribution positively influences 24-h muscle protein synthesis in healthy adults","authors":"Mamerow MM, Mettler JA, English KL, et al.","year":2014,"journal":"J Nutr","pmid":"24477298","url":"https://pubmed.ncbi.nlm.nih.gov/24477298/"},{"id":"6","title":"Protein ingestion to stimulate myofibrillar protein synthesis requires greater relative protein intakes in healthy older versus younger men","authors":"Moore DR, Churchward-Venne TA, Witard O, et al.","year":2015,"journal":"J Gerontol A Biol Sci Med Sci","pmid":"25056502","url":"https://pubmed.ncbi.nlm.nih.gov/25056502/"},{"id":"7","title":"Dietary intake of total, animal, and plant proteins and risk of all cause, cardiovascular, and cancer mortality: systematic review and dose-response meta-analysis of prospective cohort studies","authors":"Naghshi S, Sadeghi O, Willett WC, et al.","year":2020,"journal":"BMJ","pmid":"32699048","url":"https://pubmed.ncbi.nlm.nih.gov/32699048/"},{"id":"8","title":"Association of Animal and Plant Protein Intake With All-Cause and Cause-Specific Mortality","authors":"Song M, Fung TT, Hu FB, et al.","year":2016,"journal":"JAMA Intern Med","pmid":"27479196","url":"https://pubmed.ncbi.nlm.nih.gov/27479196/"},{"id":"9","title":"Dietary protein intake is associated with lean mass change in older, community-dwelling adults: the Health, Aging, and Body Composition (Health ABC) Study","authors":"Houston DK, Nicklas BJ, Ding J, et al.","year":2008,"journal":"Am J Clin Nutr","pmid":"18175749","url":"https://pubmed.ncbi.nlm.nih.gov/18175749/"},{"id":"10","title":"FoodData Central (SR Legacy): protein content of common foods","authors":"U.S. Department of Agriculture, Agricultural Research Service","year":2019,"journal":"FoodData Central","url":"https://fdc.nal.usda.gov/"},{"id":"11","title":"Dietary protein and bone health: a systematic review and meta-analysis from the National Osteoporosis Foundation","authors":"Shams-White MM, Chung M, Du M, et al.","year":2017,"journal":"Am J Clin Nutr","pmid":"28404575","url":"https://pubmed.ncbi.nlm.nih.gov/28404575/"},{"id":"12","title":"Low protein intake is associated with a major reduction in IGF-1, cancer, and overall mortality in the 65 and younger but not older population","authors":"Levine ME, Suarez JA, Brandhorst S, et al.","year":2014,"journal":"Cell Metab","pmid":"24606898","url":"https://pubmed.ncbi.nlm.nih.gov/24606898/"}],"wordCount":1030,"source":{"path":"src/content/topics/protein-intake/how-much-protein-do-you-need.md"},"citeAs":"“How much protein do you really need, and from which sources?.” What's Healthy and Why. https://whatshealthyandwhy.com/protein-intake/how-much-protein-do-you-need","notice":"General information backed by peer-reviewed research, not medical advice."}