Every number, with the study it came from.

The rule: 0.7 to 1.0 g of protein per pound of ideal body weight

The RDA of 0.8 g per kilogram was set to prevent deficiency in the general population, not to keep muscle on an adult past forty [4]. Measured directly in women over 65, the requirement came out near 1.3 g/kg [6]. Position papers for older adults set 1.0 to 1.2 g/kg as a floor and more with illness or training [3]; sports nutrition sets 1.4 to 2.0 for people who exercise [5]. When 49 trials of adults who lift were pooled, extra protein added muscle and strength and the gain levelled off near 1.6 g/kg, with the confidence interval reaching 2.2 [1] [2]. The national dietary guidelines released in January 2026 now say 1.2 to 1.6 g/kg for adults under 75 [62].

In pounds, 1.6 to 2.2 g/kg is 0.7 to 1.0 g per pound. We apply it to ideal body weight, not current weight, because protein feeds lean tissue rather than fat; that is the basis bariatric guidelines use [54]. Ideal weight is estimated with the Hamwi method, the bedside formula dietitians use: 100 lb at 5 ft plus 5 lb per inch for women, 106 plus 6 for men [52]. Other formulas give numbers within about 10% of it [53], which is why the site shows a range and lets you enter your own goal weight. Two guards: people already below their ideal weight use actual weight, and anyone with kidney disease gets a number from their own doctor [41].

Where you sit in the range is decided by two things. Lifting: more protein without resistance training does not build muscle; the trials that added muscle added it to people who lift [1] [14]. Weight loss: in a calorie deficit, higher protein spared lean mass and lost more fat [13] [16], and slower loss kept more muscle than fast loss [17]. Losing weight and lifting therefore puts you at the top of the range.

Per meal, and breakfast

Older adults need about 0.40 g/kg at a meal to fully switch on muscle building, versus 0.24 in the young, which is the reason for a 25-gram floor per meal [7]. Spreading 90 g evenly across three meals raised 24-hour muscle protein synthesis about 25% compared with loading it into dinner [8], and 40 g after a whole-body workout built more than 20, so the old "30 g limit" is a myth [9] [10]. Breakfast is where the shortfall lives: older Americans eat small protein breakfasts and put more than half the day's protein into one meal [11]. Timing around the workout does not matter in older women who lift; the day's total does [32]. Longer-term evidence that even distribution changes muscle mass is weaker than the acute studies; total daily intake is the lever, and spreading it is how you reach the total.

Protein and appetite

Protein is the most filling of the three nutrients and costs the most energy to digest, though the calorie effect is small; fullness is the bigger lever [43]. When people ate freely on a 30% protein diet, they cut 441 calories a day and lost 4.9 kg in 12 weeks without being asked to eat less [42].

Protein quality: plants, powders, collagen, leucine

At matched intake, vegans and omnivores gained the same muscle and strength from lifting [44]. Per gram, plant proteins are a little less effective, so plant eaters aim for the top of the range and lean on soy and pea, which score as high-quality proteins; collagen scores zero because it lacks an essential amino acid [45]. In older women, whey switched on muscle building and collagen did not, even at matched doses [46]. Whole eggs built more muscle than the same protein from egg whites, so real food carries more than its protein count [47]. Leucine supplements added nothing to lifting with enough protein, in older women and in peri- and postmenopausal women [30] [31].

GLP-1 medicines

In the semaglutide trial's body-composition substudy, about 40% of the weight lost was lean soft tissue, which includes water and organ tissue as well as muscle [22]. On tirzepatide, about a quarter of the loss was lean, the same proportion as placebo dieters, so the loss is not unique to the drug; it is what large weight loss does without protection [23] [24]. A GLP-1 medicine plus supervised exercise kept fat-free mass and doubled fat loss compared with the medicine alone [27]. Four medical societies now advise protein of 1.2 to 1.6 g/kg spread across meals plus resistance training, and call protein without lifting "likely inadequate" [25]; a global consensus group says the same [26].

Menopause

Across the transition, muscle responds less to both food and training, and falling estrogen may speed muscle protein breakdown [28]. Weight rises steadily with age with no jump at menopause, but from the start of the transition fat gain doubles, lean mass falls, and fat moves to the middle [33]. Energy burn, adjusted for size and muscle, holds steady from 20 to 60: there is no menopause cliff in metabolism [21]. In older women who lift, muscle gains kept improving as protein rose past the RDA [29]. After menopause BMI misses fat: a BMI of 30 caught only a third of women who were obese by body fat [38], and roughly 25 to 35% body fat is a healthy landing zone [37]. Whole soy foods are safe, useful protein and modestly reduce hot flashes [36].

Weight loss: pace, deficit, and the named diets

Losing about 0.7% of body weight a week while lifting gained lean mass; 1.4% a week did not [18]. In postmenopausal women, severe restriction lost twice the weight but proportionally more lean mass and about two and a half times more hip bone density than moderate restriction [19]. Across 52 studies of middle-aged and older adults, four in five diet-only groups lost at least 15% of their weight as lean mass; with exercise, two in five [12]. Resistance training three times a week prevented about 94% of that loss [15], and in older adults losing 10% of their weight it protected lean mass and hip bone far better than aerobic exercise alone [84].

A healthy low-fat and a healthy low-carb diet lost the same weight over a year, and adherence predicted success in both [67]. Across 121 trials, most named diets lose 4 to 5 kg at six months and the differences fade by a year [68]. Low-carbohydrate eating raises type 2 diabetes remission at six months [69], and remission tracks the weight lost, not the diet's name [70]. Fasting windows add nothing on top of a calorie deficit [73] [72]. Metabolism slows only modestly after weight loss, about 50 to 100 calories a day once weight settles [20].

Food quality

In the only fully controlled inpatient trial, people offered ultra-processed meals ate about 500 calories a day more than on matched real food [55]; even when both diets met healthy-eating guidelines, minimally processed food lost about twice the weight [56]; across about ten million people it is linked with 32 adverse outcomes [57]. Adults average about 15 g of fiber a day against a target of 25 to 38 [59]; more whole grains meant lower heart disease and lower death from any cause [58]. Sugary drinks were tied to 26% higher diabetes risk [61], and the added-sugar limit is about 25 g a day for women and 36 for men [60]. Water-rich food lost more weight with less hunger [75]; a vegetable-rich pattern lowered blood pressure by about 11 points [71]; eating vegetables and protein before the starch blunted the blood-sugar rise by about a third [74].

Replacing saturated with unsaturated fat cut cardiovascular events by about 17% [63]; a Mediterranean pattern with olive oil or nuts cut major events by about 30% [64]; a fish-oil capsule did not prevent heart disease [65]; seed oils do not raise inflammation in trials [66]. Psyllium lowers LDL and helps constipation [89]. Sodium under 2,300 mg, ideally 1,500 with hypertension [80].

Sleep, water, alcohol

Two nights of short sleep raised the hunger hormone ghrelin 28% and hunger 24% [94]; extending short sleep by about 1.2 hours cut intake by 270 calories a day [95]. Two cups of water before meals gave older adults about 44% more weight loss in one small trial [76]; older adults need scheduled fluids because thirst fades [81]. Alcohol fragments the second half of the night from about two drinks [78], a heavy dose after training cut muscle building by about a quarter [77], and it is linked to seven cancers [79].

Bone, joints, and weight

Calcium 1,000 to 1,200 mg a day, food first [82]; routine vitamin D testing is not recommended for healthy adults, with supplementation suggested over 75 or with a reason [83]. Each pound lost takes about four pounds of load off the knee with every step [85]; losing 10% or more of body weight gave the largest pain relief in 454 adults with knee arthritis [86], and 20% cut pain a further 25% [87]. Omega-3 gives a small reduction in arthritis pain [88]. "Anti-inflammatory diets" for arthritis help mostly through the weight they remove.

Creatine

Creatine monohydrate at 3 to 5 g a day is the best-studied supplement for lean mass and is safe in healthy adults over years [48]. In adults 57 to 70 it added about 1.4 kg of lean tissue with lifting [49]; women carry lower stores and respond well [51]. Two years of creatine with exercise did not change bone density in postmenopausal women, so it is for muscle, not bone [50].

Behaviour

Writing down what you eat is the behaviour most reliably tied to losing weight [91]; regular self-weighing improves loss and maintenance without harm to mood [92]; habits take a median of 66 days to become automatic [93]; people who keep 30 or more pounds off for years eat breakfast, weigh weekly, move an hour a day and keep a consistent pattern [96]. Fat burners did less than diet or exercise alone [90].

References

96 sources. The homepage "studies cited" number is generated from this list at build time so the two cannot drift apart.

1. Morton RW, Murphy KT, McKellar SR, et al. 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. Br J Sports Med. 2018;52(6):376-384.
   49 trials, 1,863 adults who lift. Extra protein added muscle and strength, and the gain levelled off at about 1.6 g per kg of body weight a day (the confidence interval ran to 2.2). The benefit was smaller with age.
2. Nunes EA, Colenso-Semple L, McKellar SR, et al. Systematic review and meta-analysis of protein intake to support muscle mass and function in healthy adults. J Cachexia Sarcopenia Muscle. 2022;13(2):795-810.
   74 trials. Higher protein gives a modest lean-mass gain; 1.6 g/kg or more with lifting gave slightly better lower-body strength.
3. Bauer J, Biolo G, Cederholm T, et al. Evidence-based recommendations for optimal dietary protein intake in older people: a position paper from the PROT-AGE Study Group. J Am Med Dir Assoc. 2013;14(8):542-559.
   For adults 65 and over: 1.0 to 1.2 g/kg a day when healthy, 1.2 to 1.5 with illness, 25 to 30 g of protein at each meal, and exercise alongside it.
4. Phillips SM, Chevalier S, Leidy HJ. Protein "requirements" beyond the RDA: implications for optimizing health. Appl Physiol Nutr Metab. 2016;41(5):565-572.
   The 0.8 g/kg RDA is a floor to prevent deficiency. For health and muscle, 1.2 to 1.6 g/kg is the better target.
5. Jäger R, Kerksick CM, Campbell BI, et al. International Society of Sports Nutrition Position Stand: protein and exercise. J Int Soc Sports Nutr. 2017;14:20.
   For people who exercise: 1.4 to 2.0 g/kg a day, 0.4 g/kg per meal, spread over three to four meals.
6. Rafii M, Chapman K, Owens J, et al. Dietary protein requirement of female adults >65 years determined by the indicator amino acid oxidation technique is higher than current recommendations. J Nutr. 2015;145(1):18-24.
   In women over 65 measured directly, the requirement came out near 1.3 g/kg, well above the 0.8 RDA.
7. Moore DR, Churchward-Venne TA, Witard O, et al. Protein ingestion to stimulate myofibrillar protein synthesis requires greater relative protein intakes in healthy older versus younger men. J Gerontol A Biol Sci Med Sci. 2015;70(1):57-62.
   Older adults need about 0.40 g/kg of protein at a meal to fully switch on muscle building, versus 0.24 in the young. That is the reason for a 25 to 40 g floor per meal.
8. Mamerow MM, Mettler JA, English KL, et al. Dietary protein distribution positively influences 24-h muscle protein synthesis in healthy adults. J Nutr. 2014;144(6):876-880.
   Spreading 90 g of protein evenly across three meals raised 24-hour muscle protein synthesis about 25% compared with loading it into dinner.
9. Macnaughton LS, Wardle SL, Witard OC, et al. The response of muscle protein synthesis following whole-body resistance exercise is greater following 40 g than 20 g of ingested whey protein. Physiol Rep. 2016;4(15):e12893.
   After a full-body lifting session, 40 g of protein built more muscle than 20 g. The idea that the body cannot use more than 30 g at a sitting is a myth.
10. Schoenfeld BJ, Aragon AA. How much protein can the body use in a single meal for muscle-building? Implications for daily protein distribution. J Int Soc Sports Nutr. 2018;15:10.
    A sensible target is about 0.4 to 0.55 g/kg per meal over four meals, reaching 1.6 to 2.2 g/kg a day.
11. Berner LA, Becker G, Wise M, Doi J. Characterization of dietary protein among older adults in the United States: amount, animal sources, and meal patterns. J Acad Nutr Diet. 2013;113(6):809-815.
    Older Americans eat small protein breakfasts and pile more than half the day's protein into one meal. Breakfast is where the shortfall lives.
12. Weinheimer EM, Sands LP, Campbell WW. A systematic review of the separate and combined effects of energy restriction and exercise on fat-free mass in middle-aged and older adults. Nutr Rev. 2010;68(7):375-388.
    In 52 studies of middle-aged and older adults, 81% of diet-only groups lost at least 15% of their weight as lean mass. With exercise added, only 39% did.
13. Longland TM, Oikawa SY, Mitchell CJ, Devries MC, Phillips SM. Higher compared with lower dietary protein during an energy deficit combined with intense exercise promotes greater lean mass gain and fat mass loss. Am J Clin Nutr. 2016;103(3):738-746.
    In a hard calorie deficit with training, 2.4 g/kg of protein gained lean mass and lost more fat than 1.2 g/kg. Young men and brutal training, so the direction transfers, the size of the effect may not.
14. Verreijen AM, Engberink MF, Memelink RG, et al. Effect of a high protein diet and/or resistance exercise on the preservation of fat free mass during weight loss in overweight and obese older adults: a randomized controlled trial. Nutr J. 2017;16(1):10.
    In older adults losing weight, resistance training was what preserved lean mass. Extra protein alone did less. Lifting is the non-negotiable; protein supports it.
15. Sardeli AV, Komatsu TR, Mori MA, Gáspari AF, Chacon-Mikahil MPT. Resistance training prevents muscle loss induced by caloric restriction in obese elderly individuals: a systematic review and meta-analysis. Nutrients. 2018;10(4):423.
    Six trials in older adults with obesity: lifting three times a week prevented about 94% of the lean-mass loss that dieting alone caused.
16. Cava E, Yeat NC, Mittendorfer B. Preserving healthy muscle during weight loss. Adv Nutr. 2017;8(3):511-519.
    Weight loss by diet alone takes muscle with it. Adequate protein and resistance exercise are the two tools that keep it.
17. Ashtary-Larky D, Bagheri R, Abbasnezhad A, Tinsley GM, Alipour M, Wong A. Effects of gradual weight loss v. rapid weight loss on body composition and RMR: a systematic review and meta-analysis. Br J Nutr. 2020;124(11):1121-1132.
    Slower weight loss keeps more lean mass than fast weight loss for the same total lost.
18. Garthe I, Raastad T, Refsnes PE, Koivisto A, Sundgot-Borgen J. Effect of two different weight-loss rates on body composition and strength and power-related performance in elite athletes. Int J Sport Nutr Exerc Metab. 2011;21(2):97-104.
    Losing about 0.7% of body weight a week while lifting gained lean mass; losing 1.4% a week did not. The source of the 0.5 to 1% a week pace.
19. Seimon RV, Wild-Taylor AL, Keating SE, et al. Effect of weight loss via severe vs moderate energy restriction on lean mass and body composition among postmenopausal women with obesity: the TEMPO Diet randomized clinical trial. JAMA Netw Open. 2019;2(10):e1913733.
    101 postmenopausal women. Severe restriction lost twice the weight but proportionally more lean mass and about two and a half times more hip bone density than moderate restriction. The single best argument against crash dieting in this decade.
20. Martins C, Roekenes J, Hunter GR, Gower BA. Metabolic adaptation is not a major barrier to weight-loss maintenance. Am J Clin Nutr. 2022;115(3):655-661.
    The slowing of metabolism after weight loss is real but small once weight settles, roughly 50 to 100 calories a day. Appetite, not a broken metabolism, is the obstacle.
21. Pontzer H, Yamada Y, Sagayama H, et al. Daily energy expenditure through the human life course. Science. 2021;373(6556):808-812.
    Adjusted for body size and muscle, energy burn holds steady from age 20 to 60. There is no menopause cliff in metabolism. What changes is muscle mass and where fat is stored.
22. Wilding JPH, Batterham RL, Calanna S, et al. Once-weekly semaglutide in adults with overweight or obesity. N Engl J Med. 2021;384(11):989-1002.
    In the body-composition substudy, about 40% of the weight lost on semaglutide was lean soft tissue, which includes water and organ tissue as well as muscle.
23. Look M, Dunn JP, Kushner RF, et al. Body composition changes during weight reduction with tirzepatide in the SURMOUNT-1 study of adults with obesity or overweight. Diabetes Obes Metab. 2025;27(5):2720-2729.
    About a quarter of the weight lost on tirzepatide was lean mass, the same proportion as placebo dieters. The loss is not unique to the drug; it is what large weight loss does without protection.
24. Prado CM, Phillips SM, Gonzalez MC, Heymsfield SB. Muscle matters: the effects of medically induced weight loss on skeletal muscle. Lancet Diabetes Endocrinol. 2024;12(11):785-787.
    Reviews put lean loss on GLP-1 medicines at 25 to 39% of the weight lost. Protein and resistance training are the two tools proposed to protect it.
25. Mozaffarian D, Agarwal M, Aggarwal M, et al. Nutritional priorities to support GLP-1 therapy for obesity: a joint advisory from the American College of Lifestyle Medicine, the American Society for Nutrition, the Obesity Medicine Association, and The Obesity Society. Obesity. 2025;33(8):1475-1503.
    Four societies' advice for people on GLP-1 medicines: protein 1.2 to 1.6 g/kg a day spread across meals, resistance training, small low-fat meals during dose increases, fluids, fiber, and a plan for low-appetite days. Protein without lifting is called 'likely inadequate'.
26. Noronha JC, et al. Consensus recommendations on nutritional care for adults on GLP-1 receptor agonist therapy. Obesity Pillars. 2025;16:100222.
    A global working group's consensus: protein above 1.2 g/kg a day, evenly distributed, plus resistance training, to preserve lean mass on GLP-1 therapy.
27. Lundgren JR, Janus C, Jensen SBK, et al. Healthy weight loss maintenance with exercise, liraglutide, or both combined. N Engl J Med. 2021;384(18):1719-1730.
    GLP-1 medicine plus supervised exercise kept fat-free mass and doubled fat loss compared with the medicine alone. The best trial evidence yet that exercise changes what a GLP-1 takes off.
28. Menzies C, et al. Menopause, female sex hormones, skeletal muscle mass and muscle protein turnover in humans. J Cachexia Sarcopenia Muscle. 2026.
    Across the menopause transition, muscle responds less to both food and training, a state called anabolic resistance, and falling estrogen may speed muscle protein breakdown.
29. Ribeiro AS, et al. Minimum protein intake to maximize resistance training adaptations in untrained older women. J Strength Cond Res. 2025.
    In older women who lift, muscle gains kept improving as protein rose past the RDA, with about 1.1 g/kg a day as the minimum that worked.
30. Jacob K, et al. Resistance training, not leucine supplementation, increases muscle protein synthesis and reverses frailty in older women. GeroScience. 2025.
    Twelve weeks of lifting with enough protein raised muscle protein synthesis 47% in older women. A leucine supplement on top added nothing.
31. Funderburk LK, et al. Efficacy of L-leucine supplementation coupled with a calorie-restricted diet to promote weight loss in mid-life women. J Am Coll Nutr. 2020;39(6):556-563.
    In peri- and postmenopausal women lifting for ten weeks, 5 g of leucine a day changed nothing in fat-free mass compared with placebo. Get leucine from real protein at each meal.
32. Nabuco HCG, Tomeleri CM, Sugihara Junior P, et al. Effects of whey protein supplementation pre- or post-resistance training on muscle mass, muscular strength, and functional capacity in pre-conditioned older women. Nutrients. 2017;9(9):1064.
    In older women who lift, protein timing around the workout made no difference. Hitting the day's total is what counts.
33. Greendale GA, Sternfeld B, Huang M, et al. Changes in body composition and weight during the menopause transition. JCI Insight. 2019;4(5):e124865.
    Weight rises steadily with age with no jump at menopause, but from the start of the transition fat gain doubles, lean mass falls, and fat moves to the middle until about two years after the final period.
34. Colenso-Semple LM, D'Souza AC, Elliott-Sale KJ, Phillips SM. Current evidence shows no influence of women's menstrual cycle phase on acute strength performance or adaptations to resistance exercise training. Front Sports Act Living. 2023;5:1054542.
    Cycle syncing has no meaningful effect on strength or muscle gain. In perimenopause the point is moot anyway.
35. Schoenfeld BJ, Aragon AA, Wilborn CD, Krieger JW, Sonmez GT. Body composition changes associated with fasted versus non-fasted aerobic exercise. J Int Soc Sports Nutr. 2014;11:54.
    Fasted cardio did not burn more fat than fed cardio at matched calories.
36. Taku K, Melby MK, Kronenberg F, Kurzer MS, Messina M. Extracted or synthesized soybean isoflavones reduce menopausal hot flash frequency and severity: systematic review and meta-analysis of randomized controlled trials. Menopause. 2012;19(7):776-790.
    Soy isoflavones modestly reduce hot-flash frequency and severity. Whole soy foods are safe, useful protein for women in midlife.
37. Potter AW, Chin GC, Looney DP, Friedl KE. Defining overweight and obesity by percent body fat instead of body mass index. J Clin Endocrinol Metab. 2024.
    In a national US sample, metabolic syndrome was essentially absent in women below 30% body fat. Roughly 25 to 35% is a healthy landing zone for women around and after menopause.
38. Banack HR, Wactawski-Wende J, Hovey KM, Stokes A. Is BMI a valid measure of obesity in postmenopausal women? Menopause. 2018;25(3):307-313.
    After menopause, BMI misses fat: a BMI of 30 caught only a third of women who were obese by body fat. The waist and the mirror beat the BMI chart.
39. Devries MC, Sithamparapillai A, Brimble KS, Banfield L, Morton RW, Phillips SM. 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. J Nutr. 2018;148(11):1760-1775.
    28 trials, 1,358 healthy adults. Higher protein did not harm kidney function. People with existing kidney disease are a different question.
40. Shams-White MM, Chung M, Du M, et al. Dietary protein and bone health: a systematic review and meta-analysis from the National Osteoporosis Foundation. Am J Clin Nutr. 2017;105(6):1528-1543.
    Higher protein does not hurt bone. It showed a modest benefit at the spine. The old 'protein leaches calcium' story is not supported.
41. Kidney Disease: Improving Global Outcomes (KDIGO) CKD Work Group. KDIGO 2024 clinical practice guideline for the evaluation and management of chronic kidney disease. Kidney Int. 2024;105(4S):S117-S314.
    With chronic kidney disease, protein is set at about 0.8 g/kg and intakes above 1.3 g/kg are avoided. Anyone with kidney disease gets a number from their own doctor, not from a calculator.
42. Weigle DS, Breen PA, Matthys CC, et al. A high-protein diet induces sustained reductions in appetite, ad libitum caloric intake, and body weight despite compensatory changes in diurnal plasma leptin and ghrelin concentrations. Am J Clin Nutr. 2005;82(1):41-48.
    Raising protein from 15% to 30% of calories, with people eating as much as they liked, cut intake by 441 calories a day and lost 4.9 kg in 12 weeks.
43. Halton TL, Hu FB. The effects of high protein diets on thermogenesis, satiety and weight loss: a critical review. J Am Coll Nutr. 2004;23(5):373-385.
    Protein is the most filling of the three macronutrients and costs the most energy to digest, though the calorie effect is small; fullness is the bigger lever.
44. Hevia-Larraín V, Gualano B, Longobardi I, et al. High-protein plant-based diet versus a protein-matched omnivorous diet to support resistance training adaptations: a comparison between habitual vegans and omnivores. Sports Med. 2021;51(6):1317-1330.
    At 1.6 g/kg of protein, vegans and omnivores gained the same muscle and strength from lifting. Plant eaters need to aim higher and lean on soy, pea and legumes, but the ceiling is the same.
45. Herreman L, Nommensen P, Pennings B, Laus MC. Comprehensive overview of the quality of plant- and animal-sourced proteins based on the digestible indispensable amino acid score. Food Sci Nutr. 2020;8(10):5379-5391.
    Whey and soy score as high-quality proteins; pea is close; wheat, rice and oat are lower; collagen scores zero because it lacks tryptophan.
46. Oikawa SY, Kamal MJ, Webb EK, McGlory C, Baker SK, Phillips SM. Whey protein but not collagen peptides stimulate acute and longer-term muscle protein synthesis with and without resistance exercise in healthy older women: a randomized controlled trial. Am J Clin Nutr. 2020;111(3):708-718.
    In older women, whey switched on muscle building and collagen did not, even at matched doses. Collagen does not count toward your protein number.
47. van Vliet S, Shy EL, Abou Sawan S, et al. Consumption of whole eggs promotes greater stimulation of postexercise muscle protein synthesis than consumption of isonitrogenous amounts of egg whites in young men. Am J Clin Nutr. 2017;106(6):1401-1412.
    Whole eggs built more muscle after exercise than the same protein from egg whites. Real food carries more than its protein count.
48. Kreider RB, Kalman DS, Antonio J, et al. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. J Int Soc Sports Nutr. 2017;14:18.
    Creatine monohydrate at 3 to 5 g a day is the best-studied supplement for lean mass and is safe in healthy adults over years of use.
49. Chilibeck PD, Kaviani M, Candow DG, Zello GA. Effect of creatine supplementation during resistance training on lean tissue mass and muscular strength in older adults: a meta-analysis. Open Access J Sports Med. 2017;8:213-226.
    In adults 57 to 70, creatine plus lifting added about 1.4 kg of lean tissue and more strength than lifting alone.
50. Chilibeck PD, Candow DG, Gordon JJ, et al. A 2-yr randomized controlled trial on creatine supplementation during exercise for postmenopausal bone health. Med Sci Sports Exerc. 2023;55(10):1750-1760.
    Two years of creatine with exercise in 237 postmenopausal women did not change bone density. Creatine is for muscle, not bone.
51. Smith-Ryan AE, Cabre HE, Eckerson JM, Candow DG. Creatine supplementation in women's health: a lifespan perspective. Nutrients. 2021;13(3):877.
    Women carry 70 to 80% lower creatine stores than men, and postmenopausal women gain muscle size and function from creatine with training.
52. Variability in ideal body weight equations (Hamwi, Devine, Robinson, Miller) and their clinical use: a review. 2023.
    The four bedside formulas for ideal body weight. Hamwi (100 lb at 5 ft plus 5 lb an inch for women, 106 plus 6 for men) is the one that needs no calculator, and the one this site uses.
53. Peterson CM, Thomas DM, Blackburn GL, Heymsfield SB. Universal equation for estimating ideal body weight and body weight at any BMI. Am J Clin Nutr. 2016;103(5):1197-1203.
    A modern equation gives the weight at any target BMI for any height. For a 5 ft 5 in woman, ideal body weight lands between about 125 and 150 lb depending on the target, which is why this site shows a range and lets you enter your own goal.
54. Mechanick JI, Apovian C, Brethauer S, et al. Clinical practice guidelines for the perioperative nutrition, metabolic, and nonsurgical support of patients undergoing bariatric procedures, 2019 update. Obesity. 2020;28(4):O1-O58.
    Bariatric guidelines set protein per kilogram of ideal body weight (up to 1.5 g/kg IBW, individualised to 2.1). The precedent for using ideal rather than actual weight in people carrying extra fat.
55. Hall KD, Ayuketah A, Brychta R, et al. Ultra-processed diets cause excess calorie intake and weight gain: an inpatient randomized controlled trial of ad libitum food intake. Cell Metab. 2019;30(1):67-77.
    Living in a research unit, people offered ultra-processed meals ate about 500 calories a day more than on matched minimally processed meals, and gained weight instead of losing it.
56. Dicken SJ, et al. Ultra-processed or minimally processed diets following healthy dietary guidelines on weight and cardiometabolic health: a randomized crossover trial. Nat Med. 2025.
    Even when both diets met healthy-eating guidelines, eight weeks of minimally processed food lost about twice the weight of the ultra-processed version. The gap is smaller when the processed diet is otherwise healthy, but it is still there.
57. Lane MM, Gamage E, Du S, et al. Ultra-processed food exposure and adverse health outcomes: umbrella review of epidemiological meta-analyses. BMJ. 2024;384:e077310.
    45 meta-analyses, about 10 million people: ultra-processed food is linked with 32 adverse outcomes, most strongly early death, heart disease and depression. Observational, but consistent.
58. Aune D, Keum N, Giovannucci E, et al. Whole grain consumption and risk of cardiovascular disease, cancer, and all cause and cause specific mortality: systematic review and dose-response meta-analysis of prospective studies. BMJ. 2016;353:i2716.
    Across 45 cohorts, more whole grains meant lower heart disease and lower death from any cause, up to about 90 g a day.
59. US Department of Agriculture, Agricultural Research Service. Fiber intake of the U.S. population: What We Eat in America, NHANES 2009-2010. Dietary Data Brief No. 12.
    American adults average about 15 g of fiber a day against a target of 25 to 38 g. Almost everyone is short.
60. American Heart Association. Added sugars. heart.org.
    Added sugar limit: about 25 g a day for women, 36 g for men. One sweetened soda spends the whole allowance.
61. Malik VS, Popkin BM, Bray GA, Després JP, Willett WC, Hu FB. Sugar-sweetened beverages and risk of metabolic syndrome and type 2 diabetes: a meta-analysis. Diabetes Care. 2010;33(11):2477-2483.
    One to two sugary drinks a day was tied to 26% higher risk of type 2 diabetes. Liquid calories do not register as food, so nothing gets eaten less later.
62. US Departments of Health and Human Services and Agriculture. Dietary Guidelines for Americans, 2025-2030. Released January 2026.
    The new national guidelines raise protein to 1.2 to 1.6 g/kg for adults under 75, keep fiber and whole grains, tighten added sugar, and drop the numeric alcohol limit in favour of 'consume less'.
63. Hooper L, Martin N, Jimoh OF, Kirk C, Foster E, Abdelhamid AS. Reduction in saturated fat intake for cardiovascular disease. Cochrane Database Syst Rev. 2020;5:CD011737.
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64. Estruch R, Ros E, Salas-Salvadó J, et al. Primary prevention of cardiovascular disease with a Mediterranean diet supplemented with extra-virgin olive oil or nuts. N Engl J Med. 2018;378(25):e34.
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65. Manson JE, Cook NR, Lee IM, et al. Marine n-3 fatty acids and prevention of cardiovascular disease and cancer. N Engl J Med. 2019;380(1):23-32.
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66. Scoping review of the evidence on seed oils, linoleic acid and health. Crit Rev Food Sci Nutr. 2026.
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67. Gardner CD, Trepanowski JF, Del Gobbo LC, et al. Effect of low-fat vs low-carbohydrate diet on 12-month weight loss in overweight adults and the association with genotype pattern or insulin secretion: the DIETFITS randomized clinical trial. JAMA. 2018;319(7):667-679.
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68. Ge L, Sadeghirad B, Ball GDC, et al. Comparison of dietary macronutrient patterns of 14 popular named dietary programmes for weight and cardiovascular risk factor reduction in adults: systematic review and network meta-analysis of randomised trials. BMJ. 2020;369:m696.
    121 trials of named diets: most lose 4 to 5 kg at six months and the differences between them largely disappear by a year. The name on the diet is marketing.
69. Goldenberg JZ, Day A, Brinkworth GD, et al. Efficacy and safety of low and very low carbohydrate diets for type 2 diabetes remission: systematic review and meta-analysis of published and unpublished randomized trial data. BMJ. 2021;372:m4743.
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70. Lean MEJ, Leslie WS, Barnes AC, et al. Primary care-led weight management for remission of type 2 diabetes (DiRECT): an open-label, cluster-randomised trial. Lancet. 2018;391(10120):541-551.
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71. Appel LJ, Moore TJ, Obarzanek E, et al. A clinical trial of the effects of dietary patterns on blood pressure. N Engl J Med. 1997;336(16):1117-1124.
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72. Lowe DA, Wu N, Rohdin-Bibby L, et al. Effects of time-restricted eating on weight loss and other metabolic parameters in women and men with overweight and obesity: the TREAT randomized clinical trial. JAMA Intern Med. 2020;180(11):1491-1499.
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73. Liu D, Huang Y, Huang C, et al. Calorie restriction with or without time-restricted eating in weight loss. N Engl J Med. 2022;386(16):1495-1504.
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74. Shukla AP, Iliescu RG, Thomas CE, Aronne LJ. Food order has a significant impact on postprandial glucose and insulin levels. Diabetes Care. 2015;38(7):e98-e99.
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75. Ello-Martin JA, Roe LS, Ledikwe JH, Beach AM, Rolls BJ. Dietary energy density in the treatment of obesity: a year-long trial comparing 2 weight-loss diets. Am J Clin Nutr. 2007;85(6):1465-1477.
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76. Dennis EA, Dengo AL, Comber DL, et al. Water consumption increases weight loss during a hypocaloric diet intervention in middle-aged and older adults. Obesity. 2010;18(2):300-307.
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77. Parr EB, Camera DM, Areta JL, et al. Alcohol ingestion impairs maximal post-exercise rates of myofibrillar protein synthesis following a single bout of concurrent training. PLoS One. 2014;9(2):e88384.
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78. Systematic review and meta-analysis of the effects of alcohol on sleep architecture. Sleep Med Rev. 2024.
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79. Office of the US Surgeon General. Alcohol and cancer risk: the US Surgeon General's advisory. January 2025.
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80. American Heart Association. How much sodium should I eat per day? heart.org.
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81. Volkert D, Beck AM, Cederholm T, et al. ESPEN practical guideline: clinical nutrition and hydration in geriatrics. Clin Nutr. 2022;41(4):958-989.
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82. Bone Health and Osteoporosis Foundation. Calcium and vitamin D: healthy bones guide.
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83. Demay MB, Pittas AG, Bikle DD, et al. Vitamin D for the prevention of disease: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2024;109(8):1907-1947.
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84. Villareal DT, Aguirre L, Gurney AB, et al. Aerobic or resistance exercise, or both, in dieting obese older adults. N Engl J Med. 2017;376(20):1943-1955.
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85. Messier SP, Gutekunst DJ, Davis C, DeVita P. Weight loss reduces knee-joint loads in overweight and obese older adults with knee osteoarthritis. Arthritis Rheum. 2005;52(7):2026-2032.
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86. Messier SP, Mihalko SL, Legault C, et al. Effects of intensive diet and exercise on knee joint loads, inflammation, and clinical outcomes among overweight and obese adults with knee osteoarthritis: the IDEA randomized clinical trial. JAMA. 2013;310(12):1263-1273.
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87. Messier SP, Resnik AE, Beavers DP, et al. Intentional weight loss in overweight and obese patients with knee osteoarthritis: is more better? Arthritis Care Res. 2018;70(11):1569-1575.
    Losing 20% of body weight cut knee pain a further 25% beyond what 10 to 20% achieved. More is better, at a muscle-protecting pace.
88. Deng W, Yi Z, Yin E, Lu R, You H, Yuan X. Effect of omega-3 polyunsaturated fatty acids supplementation for patients with osteoarthritis: a meta-analysis. J Orthop Surg Res. 2023;18(1):381.
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89. Jovanovski E, Yashpal S, Komishon A, et al. Effect of psyllium (Plantago ovata) fiber on LDL cholesterol and alternative lipid targets, non-HDL cholesterol and apolipoprotein B: a systematic review and meta-analysis of randomized controlled trials. Am J Clin Nutr. 2018;108(5):922-932.
    About 10 g of psyllium a day lowered LDL cholesterol across 28 trials. It also helps the constipation that comes with GLP-1 medicines.
90. Clark JE, Welch S. Comparing effectiveness of fat burners and thermogenic supplements to diet and exercise for weight loss and cardiometabolic health: systematic review and meta-analysis. Nutr Health. 2021;27(4):445-459.
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91. Burke LE, Wang J, Sevick MA. Self-monitoring in weight loss: a systematic review of the literature. J Am Diet Assoc. 2011;111(1):92-102.
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92. Zheng Y, Klem ML, Sereika SM, Danford CA, Ewing LJ, Burke LE. Self-weighing in weight management: a systematic review of the literature. Obesity. 2015;23(2):256-265.
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93. Lally P, van Jaarsveld CHM, Potts HWW, Wardle J. How are habits formed: modelling habit formation in the real world. Eur J Soc Psychol. 2010;40(6):998-1009.
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94. Spiegel K, Tasali E, Penev P, Van Cauter E. Brief communication: sleep curtailment in healthy young men is associated with decreased leptin levels, elevated ghrelin levels, and increased hunger and appetite. Ann Intern Med. 2004;141(11):846-850.
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95. Tasali E, Wroblewski K, Kahn E, Kilkus J, Schoeller DA. Effect of sleep extension on objectively assessed energy intake among adults with overweight in real-life settings: a randomized clinical trial. JAMA Intern Med. 2022;182(4):365-374.
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96. Wing RR, Phelan S. Long-term weight loss maintenance. Am J Clin Nutr. 2005;82(1 Suppl):222S-225S.
    People who kept 30 or more pounds off for years mostly eat breakfast, weigh themselves at least weekly, move about an hour a day, and eat the same way on weekends as weekdays.