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Leny Budhi HartiLeny Budhi HartiProgram Studi Ilmu GiziProgram Studi Ilmu Gizi

Fakultas Kedokteran Universitas BrawijayaFakultas Kedokteran Universitas BrawijayaMalang, 31 Oktober 2011Malang, 31 Oktober 2011

ContentContent

DefinitionDigestion and absorption of macronutrientEnergy metabolismThe role of micronutrient in energymetabolismReview Basal Metabolic Rate

DefinitionDefinition

Metabolisme :interkonversi senyawa kimia dalam tubuh, jaluryang diambil tiap molekul, hubungan antar molekul,dan mekanisme yang mengatur aliran metabolitmelalui jalur-jalur metabolisme

DefinitionDefinition

Eksergonik ≈katabolisme

Endergonik ≈anabolisme

Metabolisme

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Digestion & Absorption ofDigestion & Absorption ofMacronutrientMacronutrient

Digestion & absorptionDigestion & absorptionof carbohydrateof carbohydrateDigestion & absorptionDigestion & absorptionof proteinof proteinDigestion & absorptionDigestion & absorptionof lipidof lipid

Digestion & Absorption ofCarbohydrate

CarbohydrateCarbohydrate

Digestion & Absorption ofCarbohydrate

Digestion & Absorption ofCarbohydrate

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Digestion & Absorption ofCarbohydrate

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Digestion & Absorption of Protein

Digestion & Absorption of Protein

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Digestion & Absorption of Lipid

Capillary

Cells ofsmall

intestine

Interstitialfluid

Triglycerides + cholesterol + protein

Lymphto

venacava

Lacteal

Golgiapparatus

SmoothER

Chylomicron

Lumen ofsmall intestine

Large fat dropletsfrom stomach

Lipaseand colipase

Emulsion

Bile saltsrecycled

Micelles

Bile saltsfrom liver

Monoglycerides andfatty acids move out ofmicelles and enter cellsby diffusion.

Pancreatic lipase andcolipase break downfats into monoglyceridesand fatty acids storedin micelles.

Chylomicrons arereleased into thelymphatic system.

Absorbed fats combinewith cholesteroland proteins in theintestinal cells to formchylomicrons.

Bile salts from liver coatfat droplets.

Cholesterol istransported into cellsby a membranetransporter.

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Summary of Macronutrient Digestin& Absorption

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Energy Metabolism

Energy in the body is available for immediate use inthe form of adenosine triphosphate (ATP).ATP is classified as a high-energy compound and isstored in the tissues in small amountsATP may be formed from either carbohydrate, fat, orprotein

Energy Metabolism Energy Metabolism

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Energy Metabolism Energy Metabolism

Energy Metabolism

Glukosa-6fosfat

Asetil KoA Gliserol 3fosfat

Triasilgliserol (TG)Triasilgliserol (TG)

FFAFFA GliserolGliserol

Jaringan adiposa

Energy Metabolism

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Energy Metabolism Energy Metabolism

Energy Metabolism Energy Metabolism

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What nutrients areWhat nutrients arenecessary for thenecessary for theoperation of the humanoperation of the humanenergy systems?energy systems?

MikronutrientMikronutrient

break up andtransform someenergy compoundsby a process knownas hydrolysis

Water niacin serves animportant functioninglycolysis

Niasin

thiamin is needed to convertthiamin is needed to convertglycolyticglycolytic end products toend products toacetylacetyl CoACoA for entrance intofor entrance intothe Krebs cyclethe Krebs cycle

ThiamThiaminin isis

essential to forming ATPessential to forming ATPthrough the Krebs cyclethrough the Krebs cycleand electronand electrontransfer systemtransfer system

RiboflRiboflavinavin

MikronutrientMikronutrient

Basal Metabolic Rate &Basal Metabolic Rate &Resting EnergyResting EnergyEexpenditureEexpenditure

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Basal Metabolic RateBasal Metabolic Rate

• Basal metabolism, or the basal metabolic rate(BMR), represents the energy requirements ofthe many different cellular and tissueprocesses that are necessary to continuingphysiological activities in a resting,postabsorptive state throughout most of theday

Resting Energy ExpenditureResting Energy Expenditure

• The resting metabolic rate (RMR) is slightlyhigher than the BMR.

• It represents the BMR plus small amounts ofadditional energy expenditure associated witheating and previous muscular activity.

• According to the National Research Council,the BMR and RMR differ by less than 10percent

Effect Eating Meal to Matbolic Rate

• The significant elevation of the metabolic ratethat occurs after ingestion of a meal waspreviously known as the specific dynamicaction of food but is now often referred to asdietary-induced thermogenesis (DIT) orthermic effect of food (TEF).

Effect Eating Meal to Matabolic Rate

TEFTEF

AlcoholAlcohol

CaloriCaloricontrntcontrnt

Type ofType offoodfood

TEF of carbohydrate :TEF of carbohydrate :55 –– 10%10%

TEF of protein : 20TEF of protein : 20 ––30%30%

TEF of fat : 0TEF of fat : 0 –– 5%5% TEF of alcohol : 15%TEF of alcohol : 15% Normal increase ofNormal increase of

BMR due to TEF fromBMR due to TEF frommix meal : 5mix meal : 5 –– 10%10%

TEF of carbohydrate :TEF of carbohydrate :55 –– 10%10%

TEF of protein : 20TEF of protein : 20 ––30%30%

TEF of fat : 0TEF of fat : 0 –– 5%5% TEF of alcohol : 15%TEF of alcohol : 15% Normal increase ofNormal increase of

BMR due to TEF fromBMR due to TEF frommix meal : 5mix meal : 5 –– 10%10%

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Factors that Effect REE

REEREE

BodyBodycomposicomposi

tiontion

GeneticGenetic

EnvironEnvironmentment

Genetically leanindividuals havea higher REE

Individuals with naturallygreater muscle mass in comparisonto body fat have a higher REE

Caffeineis a stimulant andmay elicit asignificant rise inthe REESmoking cigarettesalso raises the REE.

This may be one ofthe reasons whysome individualsgain weightwhenthey stop smoking