The Chemical Senses and Nutrition

Richard D. Mattes, MPH, PhD, RD

Purdue University

West Lafayette, IN, USA

Laboratory for Sensory and Ingestive Studies

Focus on

Sweet and Fat

and

Energy Balance

HypothesisSweetness

Sweeteners

Palatability

Promotes excess consumption leading to the onset and complications of various chronic disorders (e.g., dental caries, obesity, diabetes, cardiovascular disease, fatty liver, etc.)

Saltiness

Salty substances

Palatability

Fattiness

Fatty Acids

Palatability

A Few General Comments

What is your Favorite Color?

Hedonics:

Liking

Preference

Decisions:

Choice

Quantity

Modify

Sensation:

Threshold

Intensity

Quality

Behavior:

Consume-Reject

Portion

Frequency

Anthropometrics

Weight

Composition

Genetics

Epigenetics Culture

Health Beliefs Recent Diet

Social Context

Metabolism

Health Status

Hedonics:

Liking

Preference

Decisions:

Choice

Quantity

Modify

Sensation:

Threshold

Intensity

Quality

Behavior:

Consume-Reject

Portion

Frequency

Anthropometrics

Weight

Composition

Hedonics:

Liking

Preference

Decisions:

Choice

Quantity

Modify

Sensation:

Threshold

Intensity

Quality

Behavior:

Consume-Reject

Portion

Frequency

Anthropometrics

Weight

Composition

?

Mechanism?•Lower taste sensitivity or responsiveness promotes a compensatory increase in intake leading to positive energy balance, insulin resistance…

•Higher taste sensitivity or responsiveness is rewarding and promotes an increase in intake leading to positive energy balance, insulin resistance…

HypothesisSweetness

Sweeteners

Palatability

Promotes excess consumption leading to the onset and complications of various chronic disorders (e.g., dental caries, obesity, diabetes, cardiovascular disease, fatty liver, etc.)

Rogers et al., IJO 2015; doi:10.1038/ijo.2015.177

RCT’s: Substitution of NS with LCS

HypothesisSweetness

Sweeteners

Palatability

Promotes excess consumption leading to the onset and complications of various chronic disorders (e.g., dental caries, obesity, diabetes, cardiovascular disease, fatty liver, etc.)

Te Morenga L et al., BMJ 2012;345”e7492 doi: 10.1136/bmj.e7492

Iso-Energetic Substitution of Sugar Intake

HypothesisSweetness

Sweeteners

Palatability

Promotes excess consumption leading to the onset and complications of various chronic disorders (e.g., dental caries, obesity, diabetes, cardiovascular disease, fatty liver, etc.)

Witherly et al., Appetite 1980;1:53-63.

RECENT PROVOCATİVE QUESTİONS

• Oral sensing – activation of reward centers

• Microbiota – energy extraction

• Gut peptide secretion – appetitive signaling

• Rodent studies – stimulation of appetite and energy intake

• Epidemiological studies – positive association between HIS use and BMI

Woods SC. Cell Metab 2009;9:489-498.Duca & Covasa Br J Nutr 2012; 108: 778-793Hagan & Niswender. Pediatr Blood Cancer 2012;58:149-153

1960’s – 1970’s 1980’s – 2010’s 2010’s – Present

Hunger

Meal Initiation

Fullness

Meal SizeReward

???

Endogenous Signals

(e.g., Insulin, Leptin)Hypothalamus

Frontal Cortex

Amygdala

Acumbens

etc.

Neural Connections

Exogenous Signals

(e.g., Drugs, Foods)

HomeostaticNon

Homeostatic

Endogenous Signals

(e.g., Insulin, Leptin)Hypothalamus

Frontal Cortex

Amygdala

Acumbens

etc.

Neural Connections

Exogenous Signals

(e.g., Drugs, Foods)

HomeostaticNon

Homeostatic

HYPER-PALATABLE FOODS

• High fat

• High sugar

• Energy dense

• Highly processed

CONSİDER

• Was food less palatable earlier in time?

• If highly processed foods are addictive because they are rapidly

absorbed, why is fat implicated?

• There is no evidence linking any specific nutrient or food to

addictive behavior – any food can be rewarding when hungry

• Best estimates are addiction is present only in <5% of the

population, so does not account for obesity prevalence

RECENT PROVOCATİVE QUESTİONS

• Oral sensing – activation of reward centers

• Microbiota – energy extraction

• Gut peptide secretion – appetitive signaling

• Rodent studies – stimulation of appetite and energy intake

• Epidemiological studies – positive association between HIS use and BMI

Palmnas et al., PLOSone 2014;9:e109841

Suez et al., Nature 2014 doi:10.1038/nature13793

Palmnas et al., PLOSone 2014;9:e109841

RECENT PROVOCATİVE QUESTİONS

• Oral sensing – activation of reward centers

• Microbiota – energy extraction

• Gut peptide secretion – appetitive signaling

• Rodent studies – stimulation of appetite and energy intake

• Epidemiological studies – positive association between HIS use and BMI

Mace et al., J Physiol 2007;582:379-392.

30

31

32

Azari et al., Am J Clin Nutr 2017;105:1001-1009

Cephalic Phase Responses

Just et al., Appetite 2008;51:622-627

Teff et al., 1993;42:1600-1608

Escandon-Calles J, Robbins DC. Diabetes 1987; 36:1167.

RECENT PROVOCATİVE QUESTİONS

• Oral sensing – activation of reward centers

• Microbiota – energy extraction

• Gut peptide secretion – appetitive signaling

• Rodent studies – stimulation of appetite and energy intake

• Epidemiological studies – positive association between HIS use and BMI

Swithers & Davidson Behav Neurosci 2008;122:161-173.

CONDİTİONİNG EQUİVALENT TO:

• 2.2 year old infant

• 1.8 liters of sweetened beverage/day

• 265 days

Fig. 2. Effects of sweet taste on measures of cumulative energy intake across the day in HASB and LASB. Hashed bars

represent LASB, solid bars represent HASB. In each pair, the dark bars on the left represent consumption after the W preload,

the pale bars on the right represent consumption after the AS preload. ⁎Significant differences ( pb0.05) between Wand AS

preloads in LASB, no differences in HASB. #Significant differences ( pb0.05) between LASB and HASB, independent of

preload.

Appleton & Blundell. Physiol Behav 2007;92:479-486.

RECENT PROVOCATİVE QUESTİONS

• Oral sensing – activation of reward centers

• Microbiota – energy extraction

• Gut peptide secretion – appetitive signaling

• Rodent studies – stimulation of appetite and energy intake

• Epidemiological studies – positive association between HIS use and BMI

Miller & Perez AJCN 2014;100:765-777

RCT trials -

Replacement

of NS with HIS

All Participants Age

Sex Food Form

Elements of a Taste PrimaryPurpose

Defined class of effective stimuli

Specialized transduction mechanism(s)

Signal conveyed by gustatory system

Perceptible and unique

Signal evokes a behavioral and/or physiological response

Present View Dietary fats are primarily in the form of Triacylglycerol and they provide an appetitive signal

Most evidence indicates humans can only “taste” non-esterified fatty acids Free fatty acids are typically aversive to humans

Consequently

In humans, fat taste is likely to function as a

warning system to discourage fat ingestion

Elements of a Taste PrimaryPurpose

Defined class of effective stimuli

Specialized transduction mechanism(s)

Signal conveyed by gustatory system

Perceptible and unique

Signal evokes a behavioral and/or physiological response

Tucker et al., Chem Senses 2015;doi:10.1093/chemse/bjv040

No limits on number of groups or samples per group

Avoid using the word “taste”

Generates a matrix for each panelist

Courcoux, Qannari, Taylor, Buck, Greenhoff 2012

A B

A B

Running et al., Chem Senses 2015; doi:1093/chemse/bjv036

“Oleogustus”

Tucker et al., PLoS One 2017;DPI:10.1371/journal.pone.0169583

Elements of a Taste PrimaryPurpose

Defined class of effective stimuli

Specialized transduction mechanism(s)

Signal conveyed by gustatory system

Perceptible and unique

Signal evokes a behavioral and/or physiological response

Without Oral Fat Stimulation/With Oral Fat Stimulation

Mattes RD. J Nutr 2002; 132: 3656-3662.

Chavez-Jauregui et al., Gastroenterology 2010;139:1538-1548

Implications of Fat Taste and a

Cephalic Phase Fat Response

1. Public Health:

CVD, Obesity Risk

2. Clinical Practice:

Phantogeusia/Dysgeusia

3. Food Industry

Develop Fat Replacers or improved flavor profile

4. Basic Biology

Summary

Sensory stimuli in foods influence health through:

Food choice

Physiological responses to food ingestion

Relationships between single sensations and intake

and/or disease risks are questionable, but food

choice and physiology can be targets for health

interventions