Body fat and fat-free mass inter-relationships: Forbes's theory revisited
Open accessAbstract
A theoretical equation was developed by Forbes that quantifies the fat-free proportion of a weight change as a function of the initial body fat. However, Forbes's equation was strictly valid only for infinitesimal weight changes. Here, I extended Forbes's equation to account for the magnitude and direction of macroscopic body weight changes. The new equation was also re-expressed in terms of an alternative representation of body composition change defined by an energy partitioning parameter called the P-ratio. The predictions of the resulting equations compared favourably with data from human underfeeding and overfeeding experiments and accounted for previously unexplained trends in the data. The magnitude of the body weight change had a relatively weak effect on the predicted body composition changes and the results were very similar to Forbes's original equation for modest weight changes. However, for large weight changes, such as the massive weight losses found in patients following bariatric surgery, Forbes's original equation consistently underestimated the fat-free mass loss, as expected. The new equation that accounts for the magnitude of the weight loss provides better predictions of body composition changes in such patients.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
The percentage of weight reduction accounted for by lean mass loss is not constant and is expected to trend higher in people rapidly experiencing large weight reductions, as observed after bariatric surgery.
“However, this percentage is not a constant and is expected to trend higher in people rapidly experiencing large weight reductions, as observed after bariatric surgery.”
From Strategies for minimizing muscle loss during use of incretin‐mimetic drugs for treatment of obesity (2025) · cites this paper as [40]
Cites
Corless, R. M., Gonnet, G. H., Hare, D. E. G., Jeffrey, D. J., & Knuth, D. E. (1996) · Advances in Computational Mathematics · doi:10.1007/bf02124750 · Cited by 6,262 · see citing works
THE BIOLOGY OF HUMAN STARVATION
Keys, A., BROŽEK, J., & Henschel, A. (1951) · The Medical Journal of Australia · doi:10.5694/j.1326-5377.1951.tb56499.x · Cited by 2,053 · see citing works
The Biology of Human Starvation: Volume I
KEYS, A., BROŽEK, J., HENSCHEL, A., MICKELSEN, O., & TAYLOR, H. L. (1950) · doi:10.5749/j.ctv9b2tqv · Cited by 2,039 · see citing works
Changes in Energy Expenditure Resulting from Altered Body Weight
Leibel, R. L., Rosenbaum, M., & Hirsch, J. (1995) · New England Journal of Medicine · doi:10.1056/nejm199503093321001 · Cited by 2,012 · see citing works
Lean Body Mass-Body Fat Interrelationships in Humans
Forbes, G. B. (2009) · Nutrition Reviews · doi:10.1111/j.1753-4887.1987.tb02684.x · Cited by 342 · see citing works
Das, S. K., Roberts, S. B., Crory, M. A. M., Hsu, L. G., Shikora, S. A., Kehayias, J. J., Dallal, G. E., & Saltzman, E. J. (2003) · American Journal of Clinical Nutrition · doi:10.1093/ajcn/78.1.22 · Cited by 210 · see citing works
Metabolic response to experimental overfeeding in lean and overweight healthy volunteers
Diaz, E., Prentice, A. M., Goldberg, G., Murgatroyd, P. R., & Coward, W. A. (1992) · American Journal of Clinical Nutrition · doi:10.1093/ajcn/56.4.641 · Cited by 187 · see citing works
Norgan, N. G., & Durnin, J. V. (1980) · The American Journal of Clinical Nutrition · doi:10.1093/ajcn/33.5.978 · Cited by 151 · see citing works
Body Fat Content Influences the Body Composition Response to Nutrition and Exercise
Forbes, G. B. (2000) · Annals of the New York Academy of Sciences · doi:10.1111/j.1749-6632.2000.tb06482.x · Cited by 145 · see citing works
(1996) · PubMed · Cited by 122 · see citing works
Pattern of lean and fat deposition in adults
Dugdale, A. E., & Payne, P. (1977) · Nature · doi:10.1038/266349a0 · Cited by 93 · see citing works
Dulloo, A. G., & Jacquet, J. (1999) · British Journal Of Nutrition · doi:10.1017/s0007114599001580 · Cited by 89 · see citing works
Body Composition and Energy Expenditure after Weight Loss Following Bariatric Surgery
Benedetti, G., Mingrone, G., Marcoccia, S., Benedetti, M. G., Giancaterini, A., Greco, A. V., Castagneto, M., & Gasbarrini, G. B. (2000) · Journal of the American College of Nutrition · doi:10.1080/07315724.2000.10718926 · Cited by 87 · see citing works
de Boer, J., van Es, A. J. H., Roovers, L., Raaij, J. V., & HAUTVAST, J. G. A. J. (1986) · American Journal of Clinical Nutrition · doi:10.1093/ajcn/44.5.585 · Cited by 83 · see citing works
van Gemert, W. G., Westerterp, K. R., van Acker, B. A. C., Wagenmakers, A. J. M., Halliday, D., Greve, J.-W. M., & Soeters, P. B. (2000) · International Journal of Obesity · doi:10.1038/sj.ijo.0801230 · Cited by 72 · see citing works
Adaptation to overeating in lean and overweight men and women.
Webb, P. M., & Annis, J. F. (1983) · PubMed · Cited by 66 · see citing works
A model for the prediction of energy balance and body weight
Payne, P., & Dugdale, A. E. (1977) · Annals of Human Biology · doi:10.1080/03014467700002521 · Cited by 62 · see citing works
Body composition changes following laparoscopic gastric banding for morbid obesity
Strauss, B. J., Marks, S. J., Growcott, J., Stroud, D. B., Lo, C. S., Dixon, J. B., & O’Brien, P. E. (2003) · Acta Diabetologica · doi:10.1007/s00592-003-0083-1 · Cited by 54 · see citing works
MECHANISMS FOR THE CONTROL OF BODY-WEIGHT
Payne, P., & Dugdale, A. E. (1977) · The Lancet · doi:10.1016/s0140-6736(77)92010-4 · Cited by 51 · see citing works
Tacchino, R. M., Mancini, A., Perrelli, M., Bianchi, A., Giampietro, A., Milardi, D., Vezzosi, C., Sacco, E., & Marinis, L. D. (2003) · Metabolism · doi:10.1053/meta.2003.50109 · Cited by 47 · see citing works
Non Linear Weight Gain with Long Term Overfeeding in Man
Dériaz, O., Tremblay, A., & Bouchard, C. (1993) · Obesity Research · doi:10.1002/j.1550-8528.1993.tb00609.x · Cited by 35 · see citing works
Wadström, C., Bäckman, L., Forsberg, A.-M., Nilsson, E., Hultman, E., Reizenstein, P., & Ekman, M. (2000) · Obesity Surgery · doi:10.1381/096089200321643313 · Cited by 34 · see citing works
Factors influencing body composition during very-low-calorie diets
Kreitzman, S. N. (1992) · American Journal of Clinical Nutrition · doi:10.1093/ajcn/56.1.217s · Cited by 11 · see citing works
Flagged first, then by citations
Cited by
Sorted by citations
Quantification of the effect of energy imbalance on bodyweight
Hall, K. D., Sacks, G., Chandramohan, D., Chow, C. C., Wang, Y. C., Gortmaker, S. L., & Swinburn, B. A. (2011) · The Lancet · doi:10.1016/s0140-6736(11)60812-x · Cited by 1,165 · see citing works
“30,38 Thus, quantification of weight change requires both a dynamic assessment of how energy expenditure changes over time as well as how energy imbalances are partitioned between storage or mobilisation of body fat and lean tissue.”
InfluentialSelf-citationHeymsfield, S. B., Gonzalez, M. C. C., Shen, W., Redman, L., & Thomas, D. (2014) · Obesity Reviews · doi:10.1111/obr.12143 · Cited by 350 · see citing works
“through differentiation (for calculation details see Supplementary Material, II)30, 31 Hall examined ΔFFM/ΔW (31) and he derived a relationship that includes a dependence on both the magnitude and direction of weight change.”
Thomas, D. M., Bouchard, C., Church, T., Slentz, C., Kraus, W. E., Redman, L. M., Martin, C. K., Silva, A. M., Vossen, M., Westerterp, K., et al. (2012) · Obesity Reviews · doi:10.1111/j.1467-789x.2012.01012.x · Cited by 280 · see citing works
“The inclusion of the parameter, C, combines the effect of gender, age and race on baseline body composition in a single parameter (36).”
Control of energy expenditure in humans
Westerterp, K. R. (2016) · European Journal of Clinical Nutrition · doi:10.1038/ejcn.2016.237 · Cited by 255 · see citing works
What is the required energy deficit per unit weight loss?
Hall, K. D. (2008) · International Journal of Obesity · doi:10.1038/sj.ijo.0803720 · Cited by 229 · see citing works
“Similarly, the energy density of the lean body mass change, rL, is determined by the metabolism of tissue glycogen and protein as well as the loss of body water associated with their Received 10 April 2007; revised 14 June 2007; accepted 9 August 2007; published online 11 September 2007 Correspondence: Dr KD Hall, LBM…”
BackgroundSelf-citationHelms, E. R., Aragon, A. A., & Fitschen, P. J. (2014) · Journal of the International Society of Sports Nutrition · doi:10.1186/1550-2783-11-20 · Cited by 266 · see citing works
“athlete [14,15,34], and keeping the deficit modest to”
BackgroundLin, B., Smith, T. A., Lee, J., & Hall, K. D. (2011) · Economics & Human Biology · doi:10.1016/j.ehb.2011.08.007 · Cited by 208 · see citing works
“Rather, the percentage of weight lost coming from body fat increases nonlinearly with body fat (Hall, 2007).”
BackgroundMethodInfluentialSelf-citationIs Weight Loss–Induced Muscle Mass Loss Clinically Relevant?
Conte, C., Hall, K. D., & Klein, S. (2024) · JAMA · doi:10.1001/jama.2024.6586 · Cited by 191 · see citing works
Self-citationThe Dynamics of Human Body Weight Change
Chow, C. C., & Hall, K. D. (2008) · PLoS Computational Biology · doi:10.1371/journal.pcbi.1000045 · Cited by 156 · see citing works
Self-citationNutritional Systems Biology Modeling: From Molecular Mechanisms to Physiology
de Graaf, A. A., Freidig, A. P., de Roos, B., Jamshidi, N., Heinemann, M., Rullmann, J. A. C., Hall, K. D., Adiels, M., & van Ommen, B. (2009) · PLoS Computational Biology · doi:10.1371/journal.pcbi.1000554 · Cited by 155 · see citing works
“The new updated equation accounted for the effects of the initial body fat mass as well as the direction and magnitude of weight change as depicted in Figure 2 showing the proportion of weight loss from body fat mass as a function of initial fat mass for different degrees of weight loss [62].”
Self-citationStrategies for minimizing muscle loss during use of incretin‐mimetic drugs for treatment of obesity
Mechanick, J. I., Butsch, W. S., Christensen, S. M., Hamdy, O., Li, Z., Prado, C. M., & Heymsfield, S. B. (2025) · Obesity Reviews · doi:10.1111/obr.13841 · Cited by 149 · see citing works
Knuth, N. D., Johannsen, D. L., Tamboli, R. A., Marks–Shulman, P. A., Huizenga, R., Chen, K. Y., Abumrad, N. N., Ravussin, É., & Hall, K. D. (2014) · Obesity · doi:10.1002/oby.20900 · Cited by 144 · see citing works
“However, bariatric surgery patients often experience a disproportionate loss of fat-free mass (FFM) (8-10) which may lead to functional deficits, especially with advancing age (11,12).”
BackgroundSelf-citationStefanakis, K., Kokkorakis, M., & Mantzoros, C. S. (2024) · Metabolism · doi:10.1016/j.metabol.2024.156057 · Cited by 142 · see citing works
Bosy-Westphal, A., & Müller, M. J. (2015) · International Journal of Obesity · doi:10.1038/ijo.2014.161 · Cited by 133 · see citing works
A simple model predicting individual weight change in humans
Thomas, D. M., Martin, C. K., Heymsfield, S. B., Redman, L. M., Schoeller, D. A., & Levine, J. A. (2011) · Journal of Biological Dynamics · doi:10.1080/17513758.2010.508541 · Cited by 124 · see citing works
“The Forbes model has been established to predict the change in FFM in numerous weight-change studies with a high degree of accuracy for group mean data 20 54 .”
MethodHelms, E. R., Zinn, C., ROWLANDS, D. S., & Brown, S. R. (2014) · International Journal of Sport Nutrition and Exercise Metabolism · doi:10.1123/ijsnem.2013-0054 · Cited by 126 · see citing works
Knuth, N. D., Johannsen, D. L., Tamboli, R. A., Marks–Shulman, P. A., Huizenga, R., Chen, K. Y., Abumrad, N. N., Ravussin, É., & Hall, K. D. (2016) · Obesity · doi:10.1002/oby.21634 · Cited by 115 · see citing works
Self-citationHeymsfield, S. B., Ebbeling, C. B., Zheng, J., Pietrobelli, A., Strauss, B. J., Silva, A. M., & Ludwig, D. S. (2015) · Obesity Reviews · doi:10.1111/obr.12261 · Cited by 111 · see citing works
“Surrogate measures, such as ‘fat-free mass’ are thus typically used to replace protein mass in relevant human energy balance models and clinical studies (48,49).”
MethodModeling weight-loss maintenance to help prevent body weight regain
Hall, K. D., & Jordan, P. N. (2008) · American Journal of Clinical Nutrition · doi:10.3945/ajcn.2008.26333 · Cited by 110 · see citing works
Self-citationBenefits of Modest Weight Loss on the Management of Type 2 Diabetes Mellitus
Lau, D. C. W., & Teoh, H. (2013) · Canadian Journal of Diabetes · doi:10.1016/j.jcjd.2013.03.023 · Cited by 96 · see citing works
Pownall, H. J., Bray, G. A., Wagenknecht, L. E., Walkup, M. P., Heshka, S., Hubbard, V. S., Hill, J., Kahn, S. E., Nathan, D. M., Schwartz, A. V., et al. (2015) · Obesity · doi:10.1002/oby.21005 · Cited by 94 · see citing works
“Intentional weight loss, which is associated with loss of lean (LM) and fat mass (FM), is a function of diet, (1) physical exercise (2,3), age, gender, ethnicity (4-7), and initial body composition (8-11).”
BackgroundMadden, A. M., Mulrooney, H. M., & Shah, S. (2016) · Journal of Human Nutrition and Dietetics · doi:10.1111/jhn.12355 · Cited by 91 · see citing works
“28) Hall, K.D. (2007) Body fat and fat-free mass inter-relationships: Forbes’s theory revisited.”
BackgroundInfluentialNavarro-Barrientos, J. E., Rivera, D. E., & Collins, L. M. (2011) · Mathematical and Computer Modelling of Dynamical Systems · doi:10.1080/13873954.2010.520409 · Cited by 87 · see citing works
“Hall [ 25 ] was the first to define p as given by the Forbes formula [ 26 ]:”
Modeling Metabolic Adaptations and Energy Regulation in Humans
Hall, K. D. (2012) · Annual Review of Nutrition · doi:10.1146/annurev-nutr-071811-150705 · Cited by 81 · see citing works
Self-citationAbeltino, A., Riente, A., Bianchetti, G., Serantoni, C., Spirito, M. D., Capezzone, S., Esposito, R., & Maulucci, G. (2024) · Nutrition Reviews · doi:10.1093/nutrit/nuae035 · Cited by 93 · see citing works
The energy balance equation: looking back and looking forward are two very different views
Schoeller, D. A. (2009) · Nutrition Reviews · doi:10.1111/j.1753-4887.2009.00197.x · Cited by 79 · see citing works
Efficacy and consequences of very-high-protein diets for athletes and exercisers
Tipton, K. D. (2011) · Proceedings of The Nutrition Society · doi:10.1017/s0029665111000024 · Cited by 78 · see citing works
Ashtary-Larky, D., Bagheri, R., Abbasnezhad, A., Tinsley, G. M., Alipour, M., & Wong, A. (2020) · British Journal of Nutrition · doi:10.1017/s000711452000224x · Cited by 72 · see citing works
“early attempts to quantify the proportion of bodyweight changes attributable to FFM and indicated a small effect of the magnitude of body weight change when initial FM is taken into account and changes in body weight are not large, such as is often observed in lifestyle interventions(9).”
BackgroundAdvances in the Science and Application of Body Composition Measurement
Baracos, V. E., Caserotti, P., Earthman, C. P., Fields, D. A., Gallagher, D., Hall, K. D., Heymsfield, S. B., Müller, M. J., Rosen, A. N., Pichard, C., et al. (2012) · Journal of Parenteral and Enteral Nutrition · doi:10.1177/0148607111417448 · Cited by 71 · see citing works
Self-citationStubbs, R. J., Hopkins, M., Finlayson, G., Duarte, C., Gibbons, C., & Blundell, J. E. (2018) · European Journal of Clinical Nutrition · doi:10.1038/s41430-018-0146-6 · Cited by 71 · see citing works
Stubbs, R. J., Morris, L., Pallister, C., Horgan, G. W., & Lavin, J. (2015) · BMC Public Health · doi:10.1186/s12889-015-2225-0 · Cited by 68 · see citing works
“However, higher energy requirements in men lead to higher ad libitum energy intakes for a given BMI [70] and we do not consider that the physiology of body composition and energy metabolism of men is the primary factor underlying differences in the responses of men and women to lifestyle-based weight management progra…”
BackgroundGerrits, M. F., Ghosh, S., Kavaslar, N., Hill, B., Tour, A., Seifert, E. L., Beauchamp, B., Gorman, S., Stuart, J., Dent, R., et al. (2010) · Journal of Lipid Research · doi:10.1194/jlr.p005298 · Cited by 64 · see citing works
Turicchi, J., O’Driscoll, R., Finlayson, G., Duarte, C., Hopkins, M., Casanova, N., Michałowska, J., Larsen, T. M., van Baak, M. A., Astrup, A. V., et al. (2019) · American Journal of Clinical Nutrition · doi:10.1093/ajcn/nqz331 · Cited by 61 · see citing works
Body Composition (Sarcopenia) in Obese Patients
Gallagher, D., & DeLegge, M. H. (2011) · Journal of Parenteral and Enteral Nutrition · doi:10.1177/0148607111413773 · Cited by 56 · see citing works
“33 Fuel utilization in the ICU patient is complex as several mediating factors or conditions have an influence: (1) underlying illness (eg, trauma, sepsis), which increases the catabolic response to injury, especially protein oxidation both in absolute terms and as a proportion of energy expenditure; (2) sedation/anal…”
BackgroundEstimating changes in free-living energy intake and its confidence interval
Hall, K. D., & Chow, C. C. (2011) · American Journal of Clinical Nutrition · doi:10.3945/ajcn.111.014399 · Cited by 56 · see citing works
Self-citationJacquet, P., Schütz, Y., Montani, J., & Dulloo, A. G. (2020) · International Journal of Obesity · doi:10.1038/s41366-020-0547-1 · Cited by 57 · see citing works
“This is consistent with the theoretical equation developed earlier by Forbes [41] that quantified the non-linear relationship between the fat-free proportion of modest weight changes as a function of the initial body fat, and later extended by Hall [42] to account for the magnitude of body weight changes.”
BackgroundInfluentialHruschka, D. J., & Hadley, C. (2016) · Obesity Reviews · doi:10.1111/obr.12449 · Cited by 56 · see citing works
Obesity pharmacotherapy in older adults: a narrative review of evidence
Henney, A. E., Wilding, J. P. H., Alam, U., & Cuthbertson, D. J. (2025) · International Journal of Obesity · doi:10.1038/s41366-024-01529-z · Cited by 51 · see citing works
“Generally, each kilogram of body weight lost constitutes ~75% fat mass and ~25% muscle mass [46], although the relationship is non-linear and governed by the magnitude of weight loss [47].”
New fat free mass - fat mass model for use in physiological energy balance equations
Thomas, D. M., Das, S. K., Levine, J. A., Martin, C. K., Mayer, L., McDougall, A., Strauss, B. J., & Heymsfield, S. B. (2010) · Nutrition & Metabolism · doi:10.1186/1743-7075-7-39 · Cited by 49 · see citing works
“Forbes and others subsequently collected various study data to test his model in a longitudinal context and the results appeared satisfactory in predicting FFM changes for any given change in FM [ 9-12 ].”
BackgroundMethodResultInfluentialThe challenges of implementing behaviour changes that lead to sustained weight management
Stubbs, R. J., & Lavin, J. (2013) · Nutrition Bulletin · doi:10.1111/nbu.12002 · Cited by 48 · see citing works
Sex differences in the composition of weight gain and loss in overweight and obese adults
Millward, D. J., Truby, H., Fox, K. R., Livingstone, M. B. E., Macdonald, I. A., & Tothill, P. (2014) · British Journal of Nutrition · doi:10.1017/s0007114513003103 · Cited by 45 · see citing works
Mechanisms of Metabolic Fuel Selection: Modeling Human Metabolism and Body-Weight Change
Hall, K. D. (2010) · IEEE Engineering in Medicine and Biology Magazine · doi:10.1109/memb.2009.935465 · Cited by 41 · see citing works
Self-citationSylivris, A., Mesinovic, J., Scott, D., & Jansons, P. (2022) · Obesity Reviews · doi:10.1111/obr.13442 · Cited by 39 · see citing works
Energy restriction and the prevention of breast cancer
Harvie, M., & Howell, A. (2012) · Proceedings of The Nutrition Society · doi:10.1017/s0029665112000195 · Cited by 38 · see citing works
Turicchi, J., O'Driscoll, R., Finlayson, G., Beaulieu, K., Deighton, K., & Stubbs, R. J. (2019) · Obesity Reviews · doi:10.1111/obr.12849 · Cited by 37 · see citing works
“A total of 5.0 (3.0) kg or 5.4% was regained in the follow‐up period, composed of 1.1 kg (3.1) FFM and 4.0 (2.7) kg FM, providing a proportionate weight gain of 21.6% FFM.”
BackgroundInfluentialJesudason, D. R., & Clifton, P. M. (2011) · International Journal of Obesity · doi:10.1038/ijo.2011.242 · Cited by 37 · see citing works
Computational modeling of cancer cachexia
Hall, K. D., & Baracos, V. E. (2008) · Current Opinion in Clinical Nutrition & Metabolic Care · doi:10.1097/mco.0b013e3282f9ae4d · Cited by 37 · see citing works
Self-citationShort and long-term energy intake patterns and their implications for human body weight regulation
Chow, C. C., & Hall, K. D. (2014) · Physiology & Behavior · doi:10.1016/j.physbeh.2014.02.044 · Cited by 36 · see citing works
“U N C O R R E C Assuming thatα is approximately constant for modest weight changes [38],we simplify the above equationby introducing parametersρ and ε to rewrite the above equation as:”
MethodSelf-citationEnergy content of weight loss: kinetic features during voluntary caloric restriction.
Heymsfield, S. B., Thomas, D., Martin, C. K., Redman, L. M., Strauss, B., Bosy-Westphal, A., Müller, M. J., Shen, W., & Martin Nguyen, A. (2012) · Metabolism · doi:10.1016/j.metabol.2011.11.012 · Cited by 36 · see citing works
“Our observations on the energy content of weight loss are consistent with those of Forbes who first reported 2-phase mathematical models for nitrogen (ie, protein) [28] and weight loss [23] during voluntary fasting or CR. Hall's [10] model includes a multiscale equation describing changes in extracellular fluids.”
InfluentialSimulating long-term human weight-loss dynamics in response to calorie restriction
Guo, J., Brager, D., & Hall, K. D. (2018) · American Journal of Clinical Nutrition · doi:10.1093/ajcn/nqx080 · Cited by 34 · see citing works
Self-citationBrowning, M. G., Franco, R. L., Cyrus, J. C., Celi, F., & Evans, R. K. (2016) · Obesity Surgery · doi:10.1007/s11695-016-2184-2 · Cited by 33 · see citing works
The threshold shift paradigm of obesity: evidence from surgically induced weight loss
Ferrannini, E., ROSENBAUM, M. S., & Leibel, R. L. (2014) · American Journal of Clinical Nutrition · doi:10.3945/ajcn.114.090167 · Cited by 33 · see citing works
Human Growth and Body Weight Dynamics: An Integrative Systems Model
Rahmandad, H. (2014) · PLoS ONE · doi:10.1371/journal.pone.0114609 · Cited by 32 · see citing works
“Moreover, the body composition equation in the current model (equation 2) leads to slightly slower change in the composition of added/lost body mass compared to the Forbes partitioning equation [18, 41] (used in H1) in extreme cases.”
ResultHow adaptations of substrate utilization regulate body composition
Hall, K. D., Bain, H., & Chow, C. C. (2007) · International Journal of Obesity · doi:10.1038/sj.ijo.0803608 · Cited by 30 · see citing works
Self-citationHigh-quality weight loss in obesity: importance of skeletal muscle
Harper, M.-E., Dent, R. R. M., & McPherson, R. (2025) · Diabetes · doi:10.2337/dbi25-0003 · Cited by 27 · see citing works
“These levels of muscle loss are in line with those that occurred with other weight loss approaches (31).”
Hruschka, D. J., Rush, E. C., & Brewis, A. (2013) · American Journal of Physical Anthropology · doi:10.1002/ajpa.22258 · Cited by 27 · see citing works
Chima, L. I., Mulrooney, H. M., Warren, J. M., & Madden, A. M. (2020) · Journal of Human Nutrition and Dietetics · doi:10.1111/jhn.12735 · Cited by 26 · see citing works
The (dys)regulation of energy storage in obesity
Levin, B. E., Geary, N., & Lutz, T. A. (2025) · Physiological Reviews · doi:10.1152/physrev.00002.2024 · Cited by 26 · see citing works
Myokines in Appetite Control and Energy Balance
Grannell, A., Kokkinos, A. D., & le Roux, C. W. (2022) · Muscles · doi:10.3390/muscles1010003 · Cited by 23 · see citing works
“However, an important difference between the human studies described above and that of Ancel Keys is that participants were living with obesity, and thus relative to lean individuals, would lose less LM during weight loss [42].”
BackgroundBrowning, M. G., & Evans, R. K. (2014) · International Journal of Adolescent Medicine and Health · doi:10.1515/ijamh-2014-0036 · Cited by 23 · see citing works
“Additionally, the degree of reduction in FFM during weight loss is inversely related to the initial body fatness (43, 44).”
BackgroundMartins, C., Gower, B. A., & Hunter, G. R. (2022) · Medicine & Science in Sports & Exercise · doi:10.1249/mss.0000000000002992 · Cited by 24 · see citing works
“weight regain) (19), and initial FM, given that baseline body composition has been shown to modulate body composition changes with weight loss (24).”
BackgroundJacquier, M., Fabien Crauste, A., Soulage, C. O., & Soula, H. A. (2014) · PLoS ONE · doi:10.1371/journal.pone.0100073 · Cited by 22 · see citing works
“Other models have been applied to humans and were focused on energy use [31,32] or relationships between fat mass and fat-free mass [33,34].”
BackgroundMethodRuff, R. R., & Zhen, C. (2015) · Annals of Epidemiology · doi:10.1016/j.annepidem.2014.12.008 · Cited by 22 · see citing works
A mathematical model of leptin resistance
Jacquier, M., Soula, H. A., & Fabien Crauste, A. (2015) · Mathematical Biosciences · doi:10.1016/j.mbs.2015.06.008 · Cited by 21 · see citing works
“One may note that fat free mass is also increased in the obese state, compared to the healthy state, as creation of fat mass leads to creation of some fat free mass, yet it has been observed experimentally that the increase in fat-free mass is smaller than the increase in fat mass [22] and the same is obtained with th…”
BackgroundJin, Z., Li, J., Thackray, A. E., Shen, T., Deighton, K., King, J. A., & Stensel, D. J. (2025) · International Journal of Obesity · doi:10.1038/s41366-025-01726-4 · Cited by 20 · see citing works
Stubbs, R. J., & Turicchi, J. (2021) · Obesity Reviews · doi:10.1111/obr.13191 · Cited by 20 · see citing works
Strain, G. W., Gagner, M., Pomp, A., Dakin, G. F., Inabnet, W. B., & Saif, T. (2011) · Surgery for Obesity and Related Diseases · doi:10.1016/j.soard.2011.09.028 · Cited by 17 · see citing works
Effect of Over- and Underfeeding on Body Composition and Related Metabolic Functions in Humans
Müller, M. J., & Bosy‐Westphal, A. (2019) · Current Diabetes Reports · doi:10.1007/s11892-019-1221-7 · Cited by 16 · see citing works
Serious analytical inconsistencies challenge the validity of the energy balance theory
Arencibia‐Albite, F. (2020) · Heliyon · doi:10.1016/j.heliyon.2020.e04204 · Cited by 16 · see citing works
“Alterations in body composition as a result of food intake restriction appear to depend primarily on the initial fat mass (FM) and on the magnitude of weight loss [23, 24, 25].”
BackgroundMethodInfluentialIndividual differences in the forced swimming test and neurochemical kinetics in the rat brain
Sequeira‐Cordero, A., Mora-Gallegos, A., Cuenca-Berger, P., & Trías, J. F. (2014) · Physiology & Behavior · doi:10.1016/j.physbeh.2014.01.037 · Cited by 16 · see citing works
Hackett, D. A., & Hagstrom, A. D. (2017) · Journal of Functional Morphology and Kinesiology · doi:10.3390/jfmk2040043 · Cited by 16 · see citing works
“Based on the first law of thermodynamics, an imbalance between energy intake and energy expenditure as a result of diet and/or exercise is accounted for by a gain or loss of body mass [2,3].”
BackgroundStubbs, R. J., Duarte, C., O’Driscoll, R., Turicchi, J., & Michałowska, J. M. (2019) · Proceedings of The Nutrition Society · doi:10.1017/s0029665119001083 · Cited by 16 · see citing works
“phase 2 of WL) most weight that is lost is in the form of reduced FM but FFM also decreases with WL, depending on initial body composition and the rate of WL((25)).”
BackgroundExploring obesity phenotypes: a longitudinal perspective
Rosero, R., Tamayo, M., Correa, R. R., Pantalone, K. M., Creel, D. B., Burguera, B. G., & Griebeler, M. L. (2025) · Reviews in Endocrine and Metabolic Disorders · doi:10.1007/s11154-025-09976-3 · Cited by 15 · see citing works
Martins, C., Nymo, S., Coutinho, S. R., Rehfeld, J. F., Hunter, G. R., & Gower, B. A. (2023) · Journal of Nutrition · doi:10.1016/j.tjnut.2023.03.026 · Cited by 13 · see citing works
Casanova, N., Beaulieu, K., Oustric, P., O’Connor, D., Gibbons, C., Duarte, C., Blundell, J. E., Stubbs, R. J., Finlayson, G., & Hopkins, M. (2020) · Obesity · doi:10.1002/oby.23034 · Cited by 13 · see citing works
“As body weight increases, FM is disproportionately increased relative to FFM (28), thus making the relationship between RMR and body weight curvilinear (29).”
BackgroundMcGrath, T., Murphy, K. G., & Jones, N. S. (2018) · Journal of The Royal Society Interface · doi:10.1098/rsif.2017.0736 · Cited by 10 · see citing works
“The law governing the partitioning of energy between the two compartments is Forbes’ law [71,72] (electronic supplementary material, S3.”
Association between insulin sensitivity and lean mass loss during weight loss
Bartholomew, C. L., Martins, C., & Gower, B. A. (2024) · Obesity · doi:10.1002/oby.24022 · Cited by 10 · see citing works
“Baseline LM was included in the models, given that baseline body composition has been shown to influence changes in body composition following weight loss [ 17].”
MethodConsistency of fat mass–fat-free mass relationship across ethnicity and sex groups
Broyles, S. T., Bouchard, C., Bray, G. A., Greenway, F. L., Johnson, W. D., Newton, R. L., Ravussin, É., Ryan, D. H., Smith, S. R., & Katzmarzyk, P. T. (2010) · British Journal Of Nutrition · doi:10.1017/s0007114510004794 · Cited by 10 · see citing works
“FM was log-transformed, based on Forbes’ empirical observations((1,4)) and on other evidence((7)) suggesting that FFM appears to be a logarithmic function of FM over the range of possible FM values.”
MethodState-of-the-art measurements in human body composition: A moving frontier of clinical importance.
Gallagher, D., Shaheen, I., & Zafar, K. (2008) · PubMed · Cited by 10 · see citing works
Real-Time Model Predictive Control of Human Bodyweight Based on Energy Intake
Fernández, A. P., Youssef, A., Heeren, C., Matthys, C., & Aerts, J. (2019) · Applied Sciences · doi:10.3390/app9132609 · Cited by 9 · see citing works
“Average Young information criterion (YIC) and coefficient of determination, R(2)T, together with their standard deviation, obtained during the system identification process for each of the 32 sub-datasets created from the Minnesota starvation excel spreadsheet used in the work of [31].”
BackgroundMethodChigutsa, E., Her, L., Ma, X., Urva, S., & Schneck, K. B. (2025) · Clinical Pharmacology & Therapeutics · doi:10.1002/cpt.3750 · Cited by 8 · see citing works
Costello, N. B., Deighton, K., Dalton‐Barron, N., Whitehead, S., Preston, T., & Jones, B. L. (2019) · European Journal of Sport Science · doi:10.1080/17461391.2019.1697373 · Cited by 8 · see citing works
“ΔE ΔBW = Pf + (Pl – Pf) ΔL ΔBW (Hall, 2007) (4)”
MethodSerra, M., Alceste, D., Hauser, F., Hulshof, P. J. M., Meijer, H. A. J., Thalheimer, A., Steinert, R. E., Gerber, P. A., Spector, A. C., Gerö, D., et al. (2023) · Frontiers in Nutrition · doi:10.3389/fnut.2023.1255499 · Cited by 7 · see citing works
Influence of previous body mass index and sex on regional fat changes in a weight loss intervention
Benito, P. J., Cupeiro, R., Peinado, A. B., Rojo, M. Á., Maffulli, N., & on behalf of the PRONAF Study Group (2017) · The Physician and Sportsmedicine · doi:10.1080/00913847.2017.1380500 · Cited by 8 · see citing works
Falkenhain, K., Redman, L. M., Chen, W. Y., Martin, C. K., Ravussin, É., & Shen, W. (2025) · Scientific Reports · doi:10.1038/s41598-024-83762-0 · Cited by 6 · see citing works
Kwan, A. T. H., Lakhani, M., & McIntyre, R. S. (2026) · Clinical Nutrition · doi:10.1016/j.clnu.2026.106620 · Cited by 6 · see citing works
González-Cano, H., Martín-Olmedo, J. J., Baz-Valle, E., Contreras, C., Schoenfeld, B. J., García‐Ramos, A., Jiménez‐Martínez, P., & Alix‐Fages, C. (2024) · The Journal of Strength and Conditioning Research · doi:10.1519/jsc.0000000000004697 · Cited by 6 · see citing works
“…AMA and PRO natural physique athletes in our study exhibited FFMI values # 25 kg · m 2 2 , it is well-known that male drug-free physique athletes may experience reductions in FFM and LBM during the competitive period, possibly because of reaching body fat levels close to essential levels (10,23).”
BackgroundHeymsfield, S. B., Ramirez, S., Yang, S., Thomas, D. M., Brown, J. C., Compton, S. L. E., Schuna, J. M., Smith, S. R., Ludwig, D. S., & Ebbeling, C. B. (2025) · Obesity · doi:10.1002/oby.24255 · Cited by 6 · see citing works
“…series of evaluations, we examined whether Δ FFM/ Δ BW with calorie restriction among the female individuals is comparable to that predicted by Forbes classic “ companionship ” rule relating Δ FFM/ Δ BW to baseline total body fat, i.e., Δ FFM/ Δ BW = 10.4/(10.4 + baseline total body fat) [23 – 26].”
InfluentialMethodological Challenges in Estimating the Lifetime Medical Care Cost Externality of Obesity
Schell, R. C., Just, D. R., & Levitsky, D. A. (2021) · Journal of Benefit-Cost Analysis · doi:10.1017/bca.2021.6 · Cited by 6 · see citing works
“We propose this 2PM both because of its reliance on more reasonable assumptions and history of use in the existing literature allowing for comparability (Thorpe et al., 2004; Wee et al., 2005; Yang & Hall, 2007; Bell et al., 2011; Cawley & Meyerhoefer, 2011; Trogdon et al., 2012).”
Müller, M. J., Braun, W., Enderle, J., & Bosy‐Westphal, A. (2022) · European Journal of Clinical Nutrition · doi:10.1038/s41430-022-01208-0 · Cited by 6 · see citing works
Dinparastisaleh, R., Khan, S. A., & Santhanam, P. (2023) · Springer eBooks · doi:10.1007/978-3-031-40116-9_33 · Cited by 7 · see citing works
Metabolic elasticity — a new trait associated with health?
Fernández‐Verdejo, R., & Galgani, J. E. (2023) · Nature Reviews Endocrinology · doi:10.1038/s41574-023-00914-4 · Cited by 5 · see citing works
Dinparastisaleh, R., Khan, S. A., & Santhanam, P. (2023) · Springer eBooks · doi:10.1007/978-3-319-12125-3_33-2 · Cited by 4 · see citing works
Energy balance, energy turnover, and risk of body fat gain
Thomas, D. M., & Westerterp, K. R. (2017) · American Journal of Clinical Nutrition · doi:10.3945/ajcn.116.141887 · Cited by 4 · see citing works
“is algebraically related to FR through the validated Forbes model (4),”
MethodChatterjee, A., Bajpai, R. C., & Gerdes, M. W. (2021) · Research Square · doi:10.21203/rs.3.rs-584141/v1 · Cited by 4 · see citing works
“Forbes [40] used crosssectional body composition data to explain the non-linear observational relationship between FFM and FM and concluded that the longitudinal change of body composition might be defined by the displacement along the cross-sectional curve theoretically.”
BackgroundMethodInfluentialBeyond Sarcopenia: A Systematic Review and Meta‐Analysis on Muscle Outcomes After Bariatric Surgery
Eksteen, G., Dubois, L., der Schueren, B. V., Vanuytsel, T., & Matthys, C. (2026) · Obesity Reviews · doi:10.1111/obr.70142 · Cited by 3 · see citing works
Glucagon‐Like Peptide‐1 Receptor Agonist‐Based Agents and Body Composition: Filling More Gaps
Dubin, R. L., Sanders, T. N., Schwab, H. M., Heymsfield, S. B., & Greenway, F. L. (2026) · Obesity · doi:10.1002/oby.70212 · Cited by 3 · see citing works
Chatterjee, A., Pahari, N., Gerdes, M. W., & Bajpai, R. C. (2022) · IEEE International Conference on e-Health Networking, Applications and Services (Healthcom) · doi:10.1109/healthcom54947.2022.9982785 · Cited by 3 · see citing works
“Forbes [17] used cross-sectional body composition data to explain the non-linear observational relationship between fat-mass (FM) and FFM.”
BackgroundMethodInfluentialModelling body weight, dieting and obesity traps
Barbieri, P. N. (2016) · Physica A Statistical Mechanics and its Applications · doi:10.1016/j.physa.2016.10.046 · Cited by 3 · see citing works
Ackland, T. R., & Stewart, A. D. (2013) · doi:10.1002/9781118692318.ch6 · Cited by 3 · see citing works
- Authors
- Hall, K. D.
- Affiliations
- National Institutes of Health (US)
- Corresponding author
- Hall, Kevin D.
- ORCID
- Hall, Kevin D.
- Venue
- British Journal of Nutrition
- Publisher
- Cambridge University Press (CUP)
- Published
- 2007-06
- Volume
- 97
- Issue
- 6
- Pages
- 1059-1063
- ISSN
- 0007-1145 (ISSN-L)
- 1475-2662
- PMC
- PMC2376748
- OpenAlex
- W2127115822
- Cited by
- 129
- References
- 23
- Citations by year
- 2026: 11 · 2025: 12 · 2024: 7 · 2023: 7 · 2022: 6 · 2021: 3 · 2020: 7 · 2019: 6 · 2018: 3 · 2017: 4 · 2016: 7 · 2015: 6 · 2014: 13 · 2013: 6 · 2012: 5
- FWCI
- 3.12
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- British Journal Of Nutrition (publishedVersion)
- PubMed (publishedVersion)
- Europe PMC (PubMed Central) (acceptedVersion)
- PubMed Central (acceptedVersion)
- Funders
- National Institutes of Health
- National Institute of Diabetes and Digestive and Kidney Diseases (Z01DK013036)
- Topics
- Health Sciences › Medicine › Physiology › Body Composition Measurement Techniques
- Life Sciences › Neuroscience › Endocrine and Autonomic Systems › Regulation of Appetite and Obesity
- Health Sciences › Medicine › Physiology › Nutrition and Health in Aging
- Keywords
- fat mass, fat-free mass, body composition changes, weight change, energy allocation, underfeeding, overfeeding, bariatric surgery, weight loss
- MeSH terms
- Adipose Tissue, Body Composition, Female, Humans, Models, Biological, Weight Gain, Weight Loss
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review