Overfeeding and Overeating: A Collection of 70+ Studies

Adam Tzur (FB, SCI-FIT),

Alex Leaf (FB, Examine.com)

Published: December 7, 2017
Updated: May 16, 2018


Overview of the overfeeding literature

If you eat more food than you need to maintain body weight, you are overfeeding or overeating. This is also known as eating a caloric surplus.

  • Body fat and lean mass typically increase when overfeeding.
  • Protein may limit body fat gain, and in some circumstances prevent it entirely.
  • Overfeeding fats and carbs typically leads to similar gains in body weight and body fat
  • Overfeeding on nuts leads to unexpectedly little body fat gain
  • The body will often partially compensate for excess energy intake by increasing energy expenditure (i.e. eat more, move more). This can help limit fat gain.

The Science of Overfeeding

In the scientific literature, overfeeding is typically done by estimating how much energy the subjects expend on a daily basis (Total Daily Energy Expenditure). Then, the scientists ask the subjects to eat more food than usual, or the food could also be provided to the subjects (aka feeding studies).

From there, they can measure how much more energy the subjects consumed compared to their habitual diet.

Some studies are done in metabolic wards where the scientists can control most relevant aspects of a subject’s life, such as physical movement, exercise, other activities, and food intake. Search for “metabolic ward” to find these studies.

Overfeeding studies are interesting because they allow researchers to measure how the body reacts to energy excess.

Overfeeding vs. overeating

Overfeeding implies that a person is feeding someone else. In the context of this study collection, researchers are overfeeding study participants. Overeating implies that a person is eating "too much" on his or her own accord.


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Quotes from overfeeding studies

“(...) despite the total increase in energy intake during the high protein phase, subjects did not experience an increase in fat mass.” - Antonio et al., 2016

"Dietary protein appears to have a protective effect against fat gain during times of energy surplus, especially when combined with resistance training. Therefore, the evidence suggests that dietary protein may be the key macronutrient in terms of promoting positive changes in body composition." - Leaf and Antonio, 2017

"Another important finding from the study was the high protein group lost a significant amount of fat mass whereas reductions in the low-protein group were not statistically significant. These results held true despite the fact that those the higher protein group ingested significantly more kilocalories (approximately 400 kcals) in the form of protein." - Campbell et al. 2018

"Among persons living in a controlled setting, calories alone account for the increase in fat; protein affected energy expenditure and storage of lean body mass, but not body fat storage." - Bray et al., 2012

"Excess energy, as fat, does not acutely increase [24 hour energy expenditure], which rises slowly as body weight increases. Excess energy as protein acutely stimulates [24 hour energy expenditure] and [sleep energy expenditure]." - Bray et al., 2015

"Interestingly, high-protein diets in both hypo- and normocaloric conditions have shown to improve body composition, whereas in combination with hypercaloric conditions does not seem to increase fat mass, when the excess energy comes from protein." - Morales et al., 2017

Overfeeding study collection

Reviews of studies (5)

Study Type Year Authors
The Effects of Overfeeding on Body Composition: The Role of Macronutrient Composition (link) Review 2017 Leaf and Antonio
What have human experimental overfeeding studies taught us about adipose tissue expansion and susceptibility to obesity and metabolic complications? (link) Review 2017 Cuthbertson et al.
Resistance to weight gain during overfeeding: a NEAT explanation (link) Review 2001 Vanltallie
Metabolic adaptations to over—and underfeeding—still a matter of debate? (link) Review 2012 Westerterp
Energy expenditure during overfeeding (link) Review 2006 Joosen and Westerterp

General overfeeding studies (13)

Study Type Year Authors
The effect of 6 weeks of overfeeding on the body weight, body composition, and energy metabolism of young men (link) Trial 1980 Norgan and Durnin
Specific appetite, energetic and metabolomics responses to fat overfeeding in resistant-to-bodyweight-gain constitutional thinness (link) Trial 2014 Germain et al.
Higher Daily Energy Expenditure and Respiratory Quotient, Rather Than Fat-Free Mass, Independently Determine Greater ad Libitum Overeating (link) Trial 2015 Piaggi
The response to long-term overfeeding in identical twins (link) Trial 1990 Bouchard et al.
Long-term increase of fat mass after a four week intervention with fast food based hyper-alimentation and limitation of physical activity (link) Trial 2010 Ernersson et al.
Effect of overfeeding macronutrients on day-to-day food intake in man (link) Trial 1996 Johnstone et al.
Effect of carbohydrate overfeeding on whole body macronutrient metabolism and expression of lipogenic enzymes in adipose tissue of lean and overweight humans (link) Trial 2004 Minehira et al.
De novo lipogenesis during controlled overfeeding with sucrose or glucose in lean and obese women (link) Trial 2001 McDevitt et al.
Overfeeding Polyunsaturated and Saturated Fat Causes Distinct Effects on Liver and Visceral Fat Accumulation in Humans (link) Trial 2014 Rosqvist et al.
A Randomized Study of the Effects of Additional Fruit and Nuts Consumption on Hepatic Fat Content, Cardiovascular Risk Factors and Basal Metabolic Rate (link) RCT 2016 Agebratt et al
Effect of 8 weeks of overfeeding on ectopic fat deposition and insulin sensitivity: testing the "adipose tissue expandability" hypothesis (link) RCT 2014 Johannsen et al.
Experimental obesity in man: cellular character of the adipose tissue (link) Trial 1971 Salans et al.
Regional differences in cellular mechanisms of adipose tissue gain with overfeeding (link) Trial 2010 Tchoukalova et al.

Fat versus carbohydrate overfeeding (6)

Study Type Year Authors
Fat and carbohydrate overfeeding in humans: different effects on energy storage (link) Trial 1995 Horton et al.
Effects of isoenergetic overfeeding of either carbohydrate or fat in young men (link) Trial 2000 Lammert et al.
Macronutrient disposal during controlled overfeeding with glucose, fructose, sucrose, or fat in lean and obese women (link) Trial 2000 McDevitt et al.
Opposite Regulation of Insulin Sensitivity by Dietary Lipid Versus Carbohydrate Excess (link) Trial 2017 Lundsgaard
Short-term overeating results in incomplete energy intake compensation regardless of energy density or macronutrient composition (link) Crossover 2014 Apolzan et al.
Effects of short-term overfeeding with fructose, fat and fructose plus fat on plasma and hepatic lipids in healthy men (link) 2010 Sobrecases et al.

Protein overfeeding (4)

Study Type Year Authors
Effect of Dietary Protein Content on Weight Gain, Energy Expenditure, and Body Composition During Overeating (link) Metabolic ward (RCT) 2012 Bray et al.
Effect of protein overfeeding on energy expenditure measured in a metabolic chamber (link) Metabolic ward (RCT) 2015 Bray et al.
Increased Protein Intake during Overfeeding Increases Energy Expenditure, Satiety, and Urinary Cortisol (presentation) Trial 2015 Graham et al.
Additional protein intake limits weight regain after weight loss in humans (link) Trial 2005 Lejeune et al.

Strength training plus overfeeding (7)

Study Type Year Authors
Daytime and nighttime casein supplements similarly increase muscle size and strength in response to resistance training earlier in the day (Free full text) RCT 2018 Joy et al.
Effects of High vs. Low Protein Intake on Body Composition and Maximal Strength in Aspiring Female Physique Athletes Engaging in an 8-Week Resistance Training Program (Free full text) Trial 2018 Campbell et al.
Daily Overfeeding from Protein and/or Carbohydrate Supplementation for Eight Weeks in Conjunction with Resistance Training Does not Improve Body Composition and Muscle Strength or Increase Markers Indicative of Muscle Protein Synthesis and Myogenesis in Resistance-Trained Males (full text) Trial 2016 Spillane and Willoughby
The effects of a high protein diet on indices of health and body composition (link) RCT 2016 Antonio et al.
A High Protein Diet Has No Harmful Effects: A One-Year Crossover Study in Resistance-Trained Males (link) Crossover 2016 Antonio et al.
The effects of consuming a high protein diet (4.4 g/kg/d) on body composition in resistance-trained individuals (full text) RCT 2014 Antonio et al.
A high protein diet (3.4 g/kg/d) combined with a heavy resistance training program improves body composition in healthy trained men and women (full text) RCT 2015 Antonio et al.

Nuts (2)

Study Type Year Authors
Effects of chronic peanut consumption on energy balance and hedonics (link) Cross-over 2002 Alper and Mattes
Two weeks of overfeeding with candy, but not peanuts, increases insulin levels and body weight (link) RCT 2009 Claesson et al.

Energy expenditure during overfeeding (11)

Study Type Year Authors
Effects of weight gain induced by controlled overfeeding on physical activity (full text) Metabolic ward (RCT) 2014 Apolzan et al.
Short-term, mixed-diet overfeeding in man: no evidence for "luxuskonsumption" (link) Trial 1985 Ravussin et al.
Thermogenesis in humans during overfeeding with medium-chain triglycerides (link) Trial 1989 Hill et al.
Spontaneous overfeeding with a 'cafeteria diet' in men: effects on 24-hour energy expenditure and substrate oxidation (link) Trial 1995 Larson et al.
Metabolic adaptation to caloric restriction and subsequent refeeding: the Minnesota Starvation Experiment revisited (link) Trial 2015 Müller et al.
Effects of energy imbalance on energy expenditure and respiratory quotient in young and older men: A summary of data from two metabolic studies (link) 1996 Saltzman and Roberts
Effects of Age on Energy Expenditure and Substrate Oxidation During Experimental Overfeeding in Healthy Men (link) Trial 1996 Roberts et al.
Decreased thermic effect of a mixed meal during overnutrition in human obesity (link) Trial 1989 Katzeff and Danforth
Energy expenditure and subsequent nutrient intakes in overfed young men (link) Trial 1990 Roberts et al.
Efficiency of autoregulatory homeostatic responses to imposed caloric excess in lean men (link) 2008 Siervo et al.
Adaptation to overeating in lean and overweight men and women (link) Trial 2008 Webb and Annis

Overfeeding and hormones (5)

Study Type Year Authors
Response of leptin to short-term and prolonged overfeeding in humans (link) Trial 1996 Kolaczynski et al.
Hormonal response to overfeeding (link) Trial 1989 Forbes et al.
Effects of short-term carbohydrate or fat overfeeding on energy expenditure and plasma leptin concentrations in healthy female subjects (link) Trial 2000 Dirlewanger
Dietary-induced alterations in thyroid hormone metabolism during overnutrition (link) Review 1979 Danforth et al.
Short-term, high-fat overfeeding impairs glycaemic control but does not alter gut hormone responses to a mixed meal tolerance test in healthy, normal-weight individuals (link) Trial 2017 Parry et al.

Observational studies (1)

Study Type Year Authors
Overeating with and without loss of control: Associations with weight status, weight-related characteristics, and psychosocial health (link) Observational 2015 Goldschmidt et al.

Genetics and gene expression (3)

Study Type Year Authors
Genotype-controlled changes in body composition and fat morphology following overfeeding in twins (link) Trial 1986 Poehlman et al.
Changes in gene expression in skeletal muscle in response to fat overfeeding in lean men (link) Trial 2007 Meugnier et al.
Beta-2 adrenergic receptor variants are associated with subcutaneous fat accumulation in response to long-term overfeeding (link) Trial 2001 Ukkola et al.

Other studies (15)

Study Type Year Authors
Eight weeks of overfeeding alters substrate partitioning without affecting metabolic flexibility in men (link) Trial 2017 Peterson et al.
Serum sex steroids and steroidogenesis-related enzyme expression in skeletal muscle during experimental weight gain in men (link) Trial 2014 Sato et al.
Short-Term Overfeeding Increases Circulating Adiponectin Independent of Obesity Status (link) Trial 2013 Cahill et al.
Predicting metabolic adaptation, body weight change, and energy intake in humans (link) 2010 Hall
Impact of prolonged overfeeding on skeletal muscle mitochondria in healthy individuals (link) Trial 2017 Toledo
Glycogen storage capacity and de novo lipogenesis during massive carbohydrate overfeeding in man (link) Trial 1988 Acheson et al.
Food for Thought: Reward Mechanisms and Hedonic Overeating in Obesity (link) Reviews 2017 Lee and Dixon
Effects of cholesterol ester transfer protein (CETP) gene on adiposity in response to long-term overfeeding (link) Twin study 2008 Terán-García et al.
Effect of fructose overfeeding and fish oil administration on hepatic de novo lipogenesis and insulin sensitivity in healthy men (link) Trial 2005 Faeh et al.
Dietary Protein Content Modulates the Amino-Acid and IGF1 Responses to Sucrose Overfeeding in Humans (link) Trial 2017 Jegatheesan et al.
A comparison of the accuracy of self-reported intake with measured intake of a laboratory overeating episode in overweight and obese women with and without binge eating disorder (link) Trial 2013 Bartholome et al.
Rapid development of systemic insulin resistance with overeating is not accompanied by robust changes in skeletal muscle glucose and lipid metabolism (link) Trial (hospital ward) 2013 Cornford et al.
Fast-food-based hyper-alimentation can induce rapid and profound elevation of serum alanine aminotransferase in healthy subjects (link) RCT 2008 Kechagias et al.
Consuming fructose-sweetened, not glucose-sweetened, beverages increases visceral adiposity and lipids and decreases insulin sensitivity in overweight/obese humans (link) Inpatient/outpatient study 2009 Stanhope et al. 2009