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Brunstrom JM, Flynn AN, Rogers PJ, Zhai Y, Schatzker M. Human nutritional intelligence underestimated? Exposing sensitivities to food composition in everyday dietary decisions. Physiol Behav 2023; 263:114127. [PMID: 36787811 DOI: 10.1016/j.physbeh.2023.114127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 02/03/2023] [Accepted: 02/11/2023] [Indexed: 02/16/2023]
Abstract
The social and cultural significance of food is woven into every aspect of our dietary behaviour, and it contributes to our complex interaction with food. To find order within this complexity scientists often look for dietary 'universals' - phenomena or basic principles that guide our food choice and meal size, irrespective of wider context. One such idea is that taste characteristics provide a signal for dietary composition (e.g., sweet taste signals carbohydrate). Others have suggested that behaviour is guided by learning and is based on associations that form between the flavour of a food and its post-ingestive effects. Despite a large body of research, evidence supporting both processes is equivocal, leading some to conclude that humans are largely indifferent to food composition. Here, we argue that human abilities to gauge the nutritional composition or value of food have been underestimated, and that they can be exposed by embracing alternative methods, including cross-cultural comparisons, large nutrition surveys, and the use of virtual portion-selection tools. Our group has focused on assessments of food choice and expected satiety, and how comparisons across everyday foods can reveal non-linear relationships with food energy density, and even the potential for sensitivity to micronutrient composition. We suggest that these abilities might reflect a complex form of social learning, in which flavour-nutrient associations are not only formed but communicated and amplified across individuals in the form of a cuisine. Thus, rather than disregarding sociocultural influences as extraneous, we might reimagine their role as central to a process that creates and imbues a 'collective dietary wisdom.' In turn, this raises questions about whether rapid dietary, technological, and cultural change disrupts a fundamental process, such that it no longer guarantees a 'nutritional intelligence' that confers benefits for health.
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Affiliation(s)
- Jeffrey M Brunstrom
- Nutrition and Behaviour Unit, School of Psychological Science, University of Bristol, Bristol, United Kingdom; NIHR Bristol Biomedical Research Centre, University Hospitals Bristol and Weston, NHS Foundation Trust and University of Bristol, United Kingdom.
| | - Annika N Flynn
- Nutrition and Behaviour Unit, School of Psychological Science, University of Bristol, Bristol, United Kingdom
| | - Peter J Rogers
- Nutrition and Behaviour Unit, School of Psychological Science, University of Bristol, Bristol, United Kingdom
| | - Yujia Zhai
- Nutrition and Behaviour Unit, School of Psychological Science, University of Bristol, Bristol, United Kingdom
| | - Mark Schatzker
- Modern Diet and Physiology Research Center, Affiliated with Yale School of Medicine, Yale University, United States
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Sclafani A, Ackroff K. Nutrient-conditioned intake stimulation does not require a distinctive flavor cue in rats. Appetite 2020; 154:104793. [PMID: 32621941 DOI: 10.1016/j.appet.2020.104793] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 05/22/2020] [Accepted: 06/26/2020] [Indexed: 10/24/2022]
Abstract
The postoral actions of nutrients in rodents can stimulate intake and condition flavor preferences through an appetition process. Appetition is revealed in rodents by their increased intake of and preference for a flavored solution paired with intragastric (IG) nutrient infusions. Here we determined if IG 16% maltodextrin (MD) infusions can stimulate intake and preference in the absence of a distinctive flavor cue. Rats implanted with IG catheters were given chow and water 2 h/day followed, 2 h later, by 20-h oral access to water paired with IG MD infusions. Other rats were given bitter sucrose octaacetate solution (SOA) paired with IG MD infusions 20 h/day. Over 8 test days, the SOA rats increased their total 20-h fluid intake (oral + IG) from 26 to 119 g/20 h and Water rats increased their intake from 31 to 96 g/20 h. When infused IG with water instead of MD in a 4-day extinction test, the SOA and Water groups reduced their fluid intakes to 45-48 g/20 h. When oral fluids were again paired with IG MD infusions, the SOA and Water groups increased their intakes to 115 and 109 g/20 h, respectively. In two-bottle tests, the SOA rats drank more SOA paired with IG MD than water paired with IG water. Water rats given the choice of a water bottle paired with IG MD and water bottle paired with IG water did not consistently prefer the H2O/ID MD bottle. Instead they displayed side or sipper tube preferences although neither cue was consistently paired with IG MD during one-bottle training.
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Affiliation(s)
- Anthony Sclafani
- Department of Psychology, Brooklyn College of the City University of New York, Brooklyn, NY, 11210, USA.
| | - Karen Ackroff
- Department of Psychology, Brooklyn College of the City University of New York, Brooklyn, NY, 11210, USA
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McGrath TM, Spreckley E, Rodriguez AF, Viscomi C, Alamshah A, Akalestou E, Murphy KG, Jones NS. The homeostatic dynamics of feeding behaviour identify novel mechanisms of anorectic agents. PLoS Biol 2019; 17:e3000482. [PMID: 31805040 PMCID: PMC6894749 DOI: 10.1371/journal.pbio.3000482] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2019] [Accepted: 11/01/2019] [Indexed: 12/26/2022] Open
Abstract
Better understanding of feeding behaviour will be vital in reducing obesity and metabolic syndrome, but we lack a standard model that captures the complexity of feeding behaviour. We construct an accurate stochastic model of rodent feeding at the bout level in order to perform quantitative behavioural analysis. Analysing the different effects on feeding behaviour of peptide YY3-36 (PYY3-36), lithium chloride, glucagon-like peptide 1 (GLP-1), and leptin shows the precise behavioural changes caused by each anorectic agent. Our analysis demonstrates that the changes in feeding behaviour evoked by the anorectic agents investigated do not mimic the behaviour of well-fed animals and that the intermeal interval is influenced by fullness. We show how robust homeostatic control of feeding thwarts attempts to reduce food intake and how this might be overcome. In silico experiments suggest that introducing a minimum intermeal interval or modulating upper gut emptying can be as effective as anorectic drug administration.
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Affiliation(s)
- Thomas M. McGrath
- Department of Mathematics, Imperial College London, London, United Kingdom
- EPSRC Centre for the Mathematics of Precision Healthcare, Imperial College London, London, United Kingdom
| | - Eleanor Spreckley
- Section of Endocrinology and Investigative Medicine, Imperial College London, London, United Kingdom
| | - Aina Fernandez Rodriguez
- Section of Endocrinology and Investigative Medicine, Imperial College London, London, United Kingdom
| | - Carlo Viscomi
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, United Kingdom
| | - Amin Alamshah
- Section of Endocrinology and Investigative Medicine, Imperial College London, London, United Kingdom
| | - Elina Akalestou
- Section of Endocrinology and Investigative Medicine, Imperial College London, London, United Kingdom
| | - Kevin G. Murphy
- Section of Endocrinology and Investigative Medicine, Imperial College London, London, United Kingdom
| | - Nick S. Jones
- Department of Mathematics, Imperial College London, London, United Kingdom
- EPSRC Centre for the Mathematics of Precision Healthcare, Imperial College London, London, United Kingdom
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Asarian L, Geary N. RYGB and flavor-consequence learning. Appetite 2019; 146:104467. [PMID: 31557496 DOI: 10.1016/j.appet.2019.104467] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 09/19/2019] [Accepted: 09/20/2019] [Indexed: 02/07/2023]
Abstract
Flavor-consequence learning refers to learned associations between flavor stimuli and post-oral consequences of food that affect food selection, amount eaten and affect. Forms of flavor-consequence learning include flavor aversions, flavor avoidance, conditioned satiety, expected satiety and appetition. Roux-en-Y gastric bypass surgery (RYGB) and other bariatric procedures alter gastrointestinal processing of food in a number of ways. Thus, it is plausible that these procedures alter post-oral unconditioned stimuli that support flavor-consequence learning, leading to altered food selection, amount eaten, and affect. Surprisingly, however, there is almost no research on the role of flavor-consequence learning in the effects of bariatric surgery on appetite. This issue urgently warrants investigation.
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Affiliation(s)
- Lori Asarian
- Department of Medicine, Larner College of Medicine, University of Vermont, Burlington, VT, 05405, USA.
| | - Nori Geary
- Department of Psychiatry, Weill Medical College of Cornell University, New York, NY, 10025, USA
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Woods SC, May-Zhang AA, Begg DP. How and why do gastrointestinal peptides influence food intake? Physiol Behav 2018; 193:218-222. [PMID: 29577941 PMCID: PMC6087670 DOI: 10.1016/j.physbeh.2018.02.048] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 02/22/2018] [Accepted: 02/24/2018] [Indexed: 12/19/2022]
Abstract
Despite the ability of some gastrointestinal hormones to reliably reduce meal size when administered prior to a meal, it is not understood why the repeated administration or genetic knockout of these hormones appear largely ineffective in reducing food intake and body weight. Here, we review evidence that the ability of GI peptides such as cholecystokinin (CCK) to elicit satiation is a consequence of prior learning. Evidence includes first, that the ability of some of these signals to modify food intake depends upon past experience and is malleable with new experience. Additionally, the ability of CCK and other gut signals to reduce food intake may not be hard-wired; i.e., any so-called "satiation" signal that reduces food intake in a single-meal situation may not continue to do so over repeated trials. The individual will respond to the signal only so long as it provides reliable information about caloric content. If a particular signal becomes unreliable, the individual will rely on other signals to end meals. Thus, gut peptides/hormones have important metabolic effects such as mediating absorption, digestion, and many aspects of the distribution of ingested nutrients throughout the body; and, if they have been reliably associated with natural stimuli that mediate satiation, they also inform behavior.
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Affiliation(s)
- Stephen C Woods
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, United States.
| | - Aaron A May-Zhang
- Department of Medicine, Vanderbilt University, Nashville, TN, United States
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Dhillon J, Running CA, Tucker RM, Mattes RD. Effects of food form on appetite and energy balance. Food Qual Prefer 2016. [DOI: 10.1016/j.foodqual.2015.03.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Doets EL, Kremer S. The silver sensory experience – A review of senior consumers’ food perception, liking and intake. Food Qual Prefer 2016. [DOI: 10.1016/j.foodqual.2015.08.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Keeping Pace with Your Eating: Visual Feedback Affects Eating Rate in Humans. PLoS One 2016; 11:e0147603. [PMID: 26828922 PMCID: PMC4734439 DOI: 10.1371/journal.pone.0147603] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Accepted: 01/06/2016] [Indexed: 11/23/2022] Open
Abstract
Deliberately eating at a slower pace promotes satiation and eating quickly has been associated with a higher body mass index. Therefore, understanding factors that affect eating rate should be given high priority. Eating rate is affected by the physical/textural properties of a food, by motivational state, and by portion size and palatability. This study explored the prospect that eating rate is also influenced by a hitherto unexplored cognitive process that uses ongoing perceptual estimates of the volume of food remaining in a container to adjust intake during a meal. A 2 (amount seen; 300ml or 500ml) x 2 (amount eaten; 300ml or 500ml) between-subjects design was employed (10 participants in each condition). In two ‘congruent’ conditions, the same amount was seen at the outset and then subsequently consumed (300ml or 500ml). To dissociate visual feedback of portion size and actual amount consumed, food was covertly added or removed from a bowl using a peristaltic pump. This created two additional ‘incongruent’ conditions, in which 300ml was seen but 500ml was eaten or vice versa. We repeated these conditions using a savoury soup and a sweet dessert. Eating rate (ml per second) was assessed during lunch. After lunch we assessed fullness over a 60-minute period. In the congruent conditions, eating rate was unaffected by the actual volume of food that was consumed (300ml or 500ml). By contrast, we observed a marked difference across the incongruent conditions. Specifically, participants who saw 300ml but actually consumed 500ml ate at a faster rate than participants who saw 500ml but actually consumed 300ml. Participants were unaware that their portion size had been manipulated. Nevertheless, when it disappeared faster or slower than anticipated they adjusted their rate of eating accordingly. This suggests that the control of eating rate involves visual feedback and is not a simple reflexive response to orosensory stimulation.
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Forde CG, Almiron-Roig E, Brunstrom JM. Expected Satiety: Application to Weight Management and Understanding Energy Selection in Humans. Curr Obes Rep 2015; 4:131-40. [PMID: 26627096 PMCID: PMC4881812 DOI: 10.1007/s13679-015-0144-0] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Recent advances in the approaches used to quantify expectations of satiation and satiety have led to a better understanding of how humans select and consume food, and the associated links to energy intake regulation. When compared calorie for calorie some foods are expected to deliver several times more satiety than others, and multiple studies have demonstrated that people are able to discriminate between similar foods reliably and with considerable sensitivity. These findings have implications for the control of meal size and the design of foods that can be used to lower the energy density of diets. These methods and findings are discussed in terms of their implications for weight management. The current paper also highlights why expected satiety may also play an important role beyond energy selection, in moderating appetite sensations after a meal has been consumed, through memory for recent eating and the selection of foods across future meals.
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Affiliation(s)
- Ciarán G Forde
- Clinical Nutrition Research Centre, Singapore Institute for Clinical Sciences, 14 Medical Drive, #07-02, Singapore, 117599, Singapore.
| | | | - Jeffrey M Brunstrom
- Nutrition and Behaviour Unit, School of Experimental Psychology, University of Bristol, Bristol, UK.
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Bolhuis DP, Lakemond CM, de Wijk RA, Luning PA, de Graaf C. Both a higher number of sips and a longer oral transit time reduce ad libitum intake. Food Qual Prefer 2014. [DOI: 10.1016/j.foodqual.2013.10.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Lin XB, Pierce DR, Light KE, Hayar A. The fine temporal structure of the rat licking pattern: what causes the variabiliy in the interlick intervals and how is it affected by the drinking solution? Chem Senses 2013; 38:685-704. [PMID: 23902635 DOI: 10.1093/chemse/bjt038] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Licking is a repetitive behavior controlled by a central pattern generator. Even though interlick intervals (ILIs) within bursts of licks are considered fairly regular, the conditions that affect their variability are unknown. We analyzed the licking pattern in rats that licked water, 10% sucrose solution, or 10% ethanol solution, in 90-min recording sessions after 4h of water deprivation. The histograms of ILIs indicate that licking typically occurred at a preferred ILI of about 130-140ms with evidence of bimodal or multimodal distributions due to occasional licking failures. We found that the longer the pause between bursts of licks, the shorter was the first ILI of the burst. When bursts of licks were preceded by a pause >4 s, the ILI was the shortest (~110ms) at the beginning of the burst, and then it increased rapidly in the first few licks and slowly in subsequent licks. Interestingly, the first ILI of a burst of licks was not significantly different when licking any of the 3 solutions, but subsequent licks exhibited a temporal pattern characteristic of each solution. The rapid deceleration in intraburst licking rate was due to an increase from ~27ms to ~56ms in the tongue-spout contact duration while the intercontact interval was only slightly changed (80-90ms). Therefore, the contact duration seems to be the major factor that increases the variability in the ILIs and could be another means for the rat to adjust the amount of fluid ingested in each individual lick.
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Affiliation(s)
- Xiong Bin Lin
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, 4301W. Markham Street Slot# 847, Little Rock, AR 72205, USA.
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Bolhuis DP, Lakemond CMM, de Wijk RA, Luning PA, de Graaf C. Consumption with large sip sizes increases food intake and leads to underestimation of the amount consumed. PLoS One 2013; 8:e53288. [PMID: 23372657 PMCID: PMC3553138 DOI: 10.1371/journal.pone.0053288] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Accepted: 11/29/2012] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND A number of studies have shown that bite and sip sizes influence the amount of food intake. Consuming with small sips instead of large sips means relatively more sips for the same amount of food to be consumed; people may believe that intake is higher which leads to faster satiation. This effect may be disturbed when people are distracted. OBJECTIVE The objective of the study is to assess the effects of sip size in a focused state and a distracted state on ad libitum intake and on the estimated amount consumed. DESIGN In this 3×2 cross-over design, 53 healthy subjects consumed ad libitum soup with small sips (5 g, 60 g/min), large sips (15 g, 60 g/min), and free sips (where sip size was determined by subjects themselves), in both a distracted and focused state. Sips were administered via a pump. There were no visual cues toward consumption. Subjects then estimated how much they had consumed by filling soup in soup bowls. RESULTS Intake in the small-sip condition was ∼30% lower than in both the large-sip and free-sip conditions (P<0.001). In addition, subjects underestimated how much they had consumed in the large-sip and free-sip conditions (P<0.03). Distraction led to a general increase in food intake (P = 0.003), independent of sip size. Distraction did not influence sip size or estimations. CONCLUSIONS Consumption with large sips led to higher food intake, as expected. Large sips, that were either fixed or chosen by subjects themselves led to underestimations of the amount consumed. This may be a risk factor for over-consumption. Reducing sip or bite sizes may successfully lower food intake, even in a distracted state.
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Affiliation(s)
- Dieuwerke P Bolhuis
- Product Design and Quality Management Group, Wageningen University, Wageningen, The Netherlands.
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Beeler JA, McCutcheon JE, Cao ZFH, Murakami M, Alexander E, Roitman MF, Zhuang X. Taste uncoupled from nutrition fails to sustain the reinforcing properties of food. Eur J Neurosci 2012; 36:2533-46. [PMID: 22712685 DOI: 10.1111/j.1460-9568.2012.08167.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Recent findings suggest the reward system encodes metabolic value independent of taste, provoking speculation that the hedonic value of taste could be derived from nutritional value as a secondary appetitive property. We therefore dissociated and compared the impact of nutrition and taste on appetitive behavior in several paradigms. Though taste alone induces preference and increased consumption, in the absence of nutritional value its reinforcing properties are greatly diminished and it does not, like sucrose, induce increased responding over time. In agreement with behavioral data, saccharin-evoked (but not sucrose-evoked) dopamine release is greatly attenuated following pre-exposure, suggesting that nutritional value is critical for dopamine-mediated reward and reinforcement. Further supporting the primacy of nutrition over taste, genetically increased dopaminergic tone enhances incentive associated with nutritional value with minimal impact on taste-based, hedonic incentive. Overall, we suggest that the sensory-hedonic incentive value associated with taste functions as a conditioned stimulus that requires nutritional value to sustainably organize appetitive behavior.
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Affiliation(s)
- Jeff A Beeler
- Department of Neurobiology, The University of Chicago, Chicago, IL, USA.
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Fernstrom JD, Munger SD, Sclafani A, de Araujo IE, Roberts A, Molinary S. Mechanisms for sweetness. J Nutr 2012; 142:1134S-41S. [PMID: 22573784 PMCID: PMC3738222 DOI: 10.3945/jn.111.149567] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
A remarkable amount of information has emerged in the past decade regarding sweet taste physiology. This article reviews these data, with a particular focus on the elucidation of the sweet taste receptor, its location and actions in taste transduction in the mouth, its nontaste functions in the gastrointestinal tract (e.g., in enteroendocrine cells), and the brain circuitry involved in the sensory processing of sweet taste. Complications in the use of rodents to model human sweet taste perception and responses are also considered. In addition, information relating to low-calorie sweeteners (LCS) is discussed in the context of these issues. Particular consideration is given to the known effects of LCS on enteroendocrine cell function.
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Affiliation(s)
- John D. Fernstrom
- University of Pittsburgh School of Medicine, Pittsburgh, PA,To whom correspondence should be addressed. E-mail:
| | | | | | - Ivan E. de Araujo
- John B. Pierce Laboratory and Yale University School of Medicine, New Haven, CT
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Frank ME, Goyert HF, Formaker BK, Hettinger TP. Effects of selective adaptation on coding sugar and salt tastes in mixtures. Chem Senses 2012; 37:701-9. [PMID: 22562765 DOI: 10.1093/chemse/bjs051] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Little is known about coding of taste mixtures in complex dynamic stimulus environments. A protocol developed for odor stimuli was used to test whether rapid selective adaptation extracted sugar and salt component tastes from mixtures as it did component odors. Seventeen human subjects identified taste components of "salt + sugar" mixtures. In 4 sessions, 16 adapt-test stimulus pairs were presented as atomized, 150-μL "taste puffs" to the tongue tip to simulate odor sniffs. Stimuli were NaCl, sucrose, "NaCl + sucrose," and water. The sugar was 98% identified but the suppressed salt 65% identified in unadapted mixtures of 2 concentrations of NaCl, 0.1 or 0.05 M, and sucrose at 3 times those concentrations, 0.3 or 0.15 M. Rapid selective adaptation decreased identification of sugar and salt preadapted ambient components to 35%, well below the 74% self-adapted level, despite variation in stimulus concentration and adapting time (<5 or >10 s). The 96% identification of sugar and salt extra mixture components was as certain as identification of single compounds. The results revealed that salt-sugar mixture suppression, dependent on relative mixture-component concentration, was mutual. Furthermore, like odors, stronger and recent tastes are emphasized in dynamic experimental conditions replicating natural situations.
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Affiliation(s)
- Marion E Frank
- Department of Oral Health and Diagnostic Sciences, Division of Periodontology, Center for Chemosensory Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT 06030-1715, USA.
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Swartz TD, Savastano DM, Covasa M. Reduced sensitivity to cholecystokinin in male rats fed a high-fat diet is reversible. J Nutr 2010; 140:1698-703. [PMID: 20592106 DOI: 10.3945/jn.110.124149] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Adult rats chronically fed a high-fat (HF) diet maintain reduced sensitivity to cholecystokinin (CCK). We hypothesized that, similar to adult rats, pups fed a HF diet would also exhibit reduced sensitivity to CCK. To test this, male pups fed low-fat (LF) and HF isoenergetic (16.2 kJ/g) diets were administered CCK intraperitoneally (0.125-1 microg/kg) 1 wk following dietary adaptation. After receiving 0.5 microg/kg CCK, pups fed the HF diet suppressed food intake less (8.9 +/- 5.0%) than pups fed the LF diet (28.9 +/- 4.7%; P < 0.05) relative to intakes after saline administration. We then assessed the development and extinction of changes in CCK sensitivity by switching the diets between the groups. The HF-fed group, when switched to the LF diet, regained sensitivity by wk 4 and suppressed food intake following administration of 0.25 microg/kg CCK (33.1 +/- 5.7%; P < 0.05). The LF-fed group, when switched to the HF diet, lost sensitivity by wk 2 and did not suppress food intake after administrations of CCK compared with saline. Finally, we examined if HF-fed rats have an increased sensitivity to corn oil during brief access tests using a multibottle gustometer. At oil concentrations of 25, 75, and 100%, rats fed the HF diet sampled more oil than LF-fed rats (P < 0.05). These findings demonstrate that male rat pups fed a HF diet exhibit reduced sensitivity to CCK, the development of this reduced sensitivity is quicker than its extinction, and rats consuming a HF diet have increased oral sensitivity to oils.
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Affiliation(s)
- Timothy D Swartz
- Department of Nutritional Sciences, College of Health and Human Development, The Pennsylvania State University, University Park, PA 16802, USA
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Hogenkamp PS, Mars M, Stafleu A, de Graaf C. Intake during repeated exposure to low- and high-energy-dense yogurts by different means of consumption. Am J Clin Nutr 2010; 91:841-7. [PMID: 20164319 DOI: 10.3945/ajcn.2009.28360] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND An important question in the regulation of energy intake is whether dietary learning of energy content depends on the food's characteristics, such as texture. Texture might affect the duration of sensory exposure and eating rate. OBJECTIVE The objective was to investigate whether a long sensory exposure, due to differences in means of consumption and in viscosity, enhances learned associations between sensory signals and metabolic consequences and hence facilitates energy intake compensation. DESIGN A total of 105 healthy young adults with a mean (+/-SD) age of 22 +/- 3 y and a body mass index (in kg/m(2)) of 21.6 +/- 1.7 participated in a parallel intervention in 3 groups: liquid yogurt with a straw (liquid/straw; n = 34), liquid yogurt with a spoon (liquid/spoon; n = 36), or semisolid yogurt with a spoon (semisolid/spoon; n = 35). Novel flavored yogurts were offered ad libitum for breakfast in 2 energy densities: low ( approximately 215 kJ/100 g) and high ( approximately 600 kJ/100 g). Subjects were repeatedly exposed to the yogurt products (10 times), and yogurt intake was measured. RESULTS Intakes (P = 0.01) and eating rates (P = 0.01) were highest in the liquid/straw group. Average intakes over 10 exposures were 575 +/- 260 g for liquid/straw, 475 +/- 192 g for liquid/spoon, and 470 +/- 223 g for semisolid/spoon; average eating rates were 132 +/- 83 g/min for liquid/straw, 106 +/- 53 g/min for liquid/spoon, and 105 +/- 88 g/min for semisolid/spoon. No significant interaction for intake between intervention group, energy density, and repeated exposure was observed, and intakes of the low- and high-energy-dense yogurts did not change over time in any of the intervention groups. CONCLUSIONS We observed no energy intake compensation after repeated exposure to yogurt products. Differences in ad libitum yogurt intake could be explained by eating rate, which was affected by the different means of consumption. This trial was registered with the Dutch trial registration at http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=1853 as NTR1853.
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