Van Aken Euro Fed Lipids Final
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Transcript of Van Aken Euro Fed Lipids Final
Monday, September 26, 2011
Together to the next level
How fat composition
and food formulation
affect absorption and
mediate food intake Which way to go? George van Aken
Key question
Fat is highly caloric, sensorially pleasant food
constituent which entices overeating
How can we avoid overeating?
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Origin of the study
Finalized project at TIFN:
Engineered Sensory and Dietary Functionality of Dispersed
Fat
• Project goals:
• Optimization of fat-related sensory and dietary effects.
• Main focus on satiety and food intake reduction.
• Key objectives:
• Gastro-intestinal behaviour of food emulsions in relation to physiological
responses.
• Physical-chemical and biochemical mechanisms behind this behaviour.
• Engineering rules to help control the processing, delivery and release of fat
in the digestive tract.
NOW focussing on application at NIZO food research
• ,
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Outline
• Fundamentals of fat digestion and absorption
• Role of fat consumption in obesity
• How can we reduce caloric intake?
• Conclusions
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FUNDAMENTALS OF FAT
DIGESTION AND ABSORPTION
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Emulsion digestion and absorption
lipases bile
Fatty acid
absorption
Regulation of
digestion and food
intake
Digestion
processes
Delivery of
-3, -6 and vitamins
blood
Fat digestion: main enzymatic processes
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Stomach
Small
intestine
Gastric lipase
(<10%)
Pancreatic lipase
(almost complete)
Small intestinal
wall
Fast
Slow
lymph
chylomicron
Serum
albumin
transporter
Short chain and
polunsaturated FFA
LCFA
liver
Routing of fatty acids - overview
C11:0 and shorter
C12:0 and longer
Oleic acid
ω-6
ω-3
Portal vein
Lymph vessel
Main
blood
stream
ω-3 DHA
VLDL
glucose
FA
glucose
chylomicrons
serum
albumin
Nerve membrane
Muscles Adiposites
LDL
Energy
supply
Functional
lipids
ROLE OF FAT CONSUMPTION
IN OBESITY
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Positive energy balance
Heilbron et al, Int. J. Obesity, (2004)
Ectopic fat storage in:
• liver
• heart
• pancreatic β-cells
• skeletal muscle,
• abdominal fat
METABOLIC SYNDROME:
Type II diabetes, OBESITY,
Inflammatory reactions, high
blood pressure,
atherosclerosis, CVD
Enlarged adipocytes:
• Impared adiposite
differentiation and
function
• Modulated
endocrine fuction
Fat storage exceeds
the normal storage
capacity of adiposites
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Ease of overeating of fat
Nutrient Caloric
value
(kcal/g)
Sensory effect Ease of
overeating
Proteins 4 Can be relatively unpleasant :
tends to a highly viscous, tough and dry
mouthfeel
small
Sugars 4 Pleasant :
viscous mouthfeel
sweet
moderate
Fats 9 Pleasant:
thin mouthfeel, lubricant, smoothening
adds to flavour richness
high
BUT: the body is designed for efficient
absorption and to control food intake
Small intestine
pancreas
Stomach
duodenum jejunum ileum
Stomach
emptying
absorptive cells Pylorus
intake
gall
bladder
Feedback
COLON
Detailed in vivo human study to confirm these feedback mechanisms are
still ongoing at TIFN in collaboration with Maastricht University
Nutrient transport through the
gastrointestinal tract is regulated
Physiological restrictions: • Vmax per unit length of small intestine
• Absorption requires transfer from polymers to monomers: • proteins amino acids
• di-, oligo-, polysaccharides monosaccharides
• triglycerides fatty acids, monoglycerides
Regulation mechanism for efficient absorption: • Efficient and gradual absorption of nutrients by small intestine
• > 95 % for a single shot of 650 g oil (220% of advised total daily caloric intake)
• Small intestinal transit time adjusted to avoid spill over into the colon
Regulation mechanisms for food intake: • Feeling of a full stomach
• related to gastric distension + the detection of nutrients in the small intestine
• Feeling of hunger • related to a low reserve of nutrient in small intestine
- GLP-1
Some main feedback mechanisms
Pylorus
duodenum jejunum ileum
L-cells
Transit speed max
storage
bile pancreas
I-cells
intake
-
CCK
-
Full stomach
Meal
ending
-
PYY,
GLP-1 No
hunger
CCK +
+
Large reservoir of nutrient
present in small intestine
CCK-B
Next
meal
Computer
modelling Fed by: physiological literature
in vitro studies
(Belly Quintet, Symphid, TIM)
Van Aken, Food Biophysics (2010) 5(4):258–283
HOW CAN WE REDUCE THE
CALORIC INTAKE?
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1. Increase feeling of a full stomach during
eating by reducing the initial fast emptying
• Gastric emptying of non-nutritional liquid is fast and
dependent on the viscosity
• Gastric emptying of nutritious liquids is much slower and
regulated at a constant release of energy (~ 2 kcal/min)
• Regulation only starts after sufficient nutrients have
entered the small intestine. This may take several minutes.
• Fullness is however dependent on both gastric distension
(increased) and nutrient detection in the small intestine
(lowered)
Simulation of an
emulsion of 30 g fat
and 200 g water;
effect of a 1000x
increase in viscosity
2. Keep a full stomach during eating by
control of emulsion stability
• Gastric emptying of nutritious liquids regulated at a
constant release of energy (~ 2 kcal/min)
• Bulk fat and many emulsions and are unstable in the
stomach (low pH, enzymes) and phase separate into
an energy- rich creamed layer (containing the fat)
and an energy-poor lower phase *
• Consequence: the energy poor lower phase empties fast, quickly reducing the volume of the stomach
• Felt as less fullness during and shortly after the meal.
*Marciani et al., British Journal of Nutrition (2009), 101, 919–928
Marciani et al. 2009 *
Simulation of an emulsion of 30 g
fat and 200 g water; effect of fat
floating until fundus and corpus
have emptied (50 ml water)
Approach: inverted phase separation in
stomach
A number of sedimenting emulsion systems
have been identified*
CURRENTLY investigated in an in vivo human trial
(TIFN, IFR, (2) Norfolk and Norwich University hospitals NNUH)
Expectation: Gastric volume reduces slowly → more fullness
during a meal → sooner meal ending
5 % triolein, 1 % WPI,
1 % caseinate
Full fat milk
Simulation of an emulsion of
30 g fat and 200 g water;
effect of fat sedimentation until
5 ml of fat is left in the antrum
* Van Aken, G.A., Bomhof, E., Zoet, F.D., Verbeek, M., Oosterveld, A., Food Hydrocolloids (2011), 25: 781-788,
Differences in in vitro gastric behaviour between homogenized milk and emulsions stabilised by Tween 80, whey protein, or whey protein
and caseinate
3. Control the rate of intestinal fat hydrolysis
Small intestinal transit time normally regulated to compensate for
a high caloric entry into the intestine or slow enzymatic hydrolysis
(“Ileal brake”)
Sugars delivered to the ileum or fat delivered to the jejunum shortly (e.g.
15 min) before a meal reduces food intake from that meal.
Compensates only; no effect on total caloric intake.
Simulation of an
emulsion of 30 g fat
and 200 g water;
effect of a 10x
slower digestion
4. Reduce the rate of intestinal
absorption of fat hydrolysis products
• Oleic acid or oleic acid + monoolein intubated into the jejunum gives a
strong hunger suppressing signal (Little et al., Am. J. Physiol.2005)
• A similarly strong effect is also found for 1,3 diglycerides
(Kristensen et al., J. Nutrition 2006; Yanai et al., Nutrition Journal, 2007)
• Stronger effect of predigested TG, oleic acid and 1,3-diglycerides also
reduces total caloric intake (overcompensation).
The excess suppression by oleic acid seems only to occur beyond a
higher level of free oleic acid intubated
(Woltman & Reidelberger, Am. J. Physiol. 1995).
ENTEROCYTE
ENTEROCYTE
Possible explanation of stronger effect of
predigested TG, oleic acid and 1,3-diglycerides
Fatty acid
receptor
glycerol-3-phosphate
pathway
SLOW
Pancreatic
lipase
absorption
monoglyceride
pathway
FAST
Pancreatic
lipase
absorption
Fullness Food intake
reduction
chylomicron
Kristensen et al., J. Nutrition 2006
Portal
vein
Lymph
vessel
Simulated effect of slower intestinal
absorption
Simulation of an
emulsion of 30 g fat
and 200 g water;
effect of a 4x
slower absorption
Most effective fat-based way to reduce hunger and
food intake?
Replace TG by fatty acids, diglycerides,
monoglycerides, non-glyceride esters
CONCLUSIONS
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summary
Fat is highly caloric, sensorially pleasant food
constituent which entices overeating
How can we avoid overeating?
Lipids are also satiating and can be used to limit food intake, but it needs to be in an
appropriate form or type
Opportunities for product development!
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Optimized formulations of fat/lipids in food may help to
• Reduce the over-eating during a liquid meal: • Avoid fat creaming in the stomach (acid and pepsin stable
emulsifiers) (ongoing in vivo human study)
• Induce gastric sedimentation of fat (dense fat structures)
(ongoing in vivo human study)
• Decrease hunger and suppress intake on next meal: • Increase the viscosity (however less fullness during the 1st meal)
• Marginal effect of slower digestion (emulsifiers that slow release
of FA)
• Large effect by slower absorption: • Replace TG by fatty acids, diglycerides,monoglycerides, non-
glyceride esters
• Release system of encapsulated fatty acids, diglycerides, non-
glyceride esters fatty acids
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Tiny TIM
:
Let’s translate:
Opportunities for product development
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Computer
modelling
SYMPHID Human
subjects
Animal Model
Belly Quintet
Food grade
pilot plant
27 Technology for your success
Together to the next level
Creating the future together