Dale A Schoeller Nutritional Sciences University of WisconsinMadison

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Dale A Schoeller Nutritional Sciences University of Wisconsin-Madison ENERGY DENSITY OF FAT AND FAT-FREE

Dale A Schoeller Nutritional Sciences University of Wisconsin-Madison ENERGY DENSITY OF FAT AND FAT-FREE MASS

Energy substrates Biochemicals that can be oxidized to produce higher energy phosphate bonds Carbohydrates

Energy substrates Biochemicals that can be oxidized to produce higher energy phosphate bonds Carbohydrates Lipids Proteins Minor amounts of other biochemicals

Energy density of macronutrients 4 -9 -4 energy rule Pro 4 kcal/g FAT 9

Energy density of macronutrients 4 -9 -4 energy rule Pro 4 kcal/g FAT 9 kcal/g CHOH 4 kcal/g Atwater factors

Dietary Energy Units Gross energy Energy released when combusted to CO 2, H 2

Dietary Energy Units Gross energy Energy released when combusted to CO 2, H 2 O and N 2 Digestible energy Energy absorbed Gross energy – fecal energy losses Metabolizable energy Energy available to the body Digestible energy – urinary energy losses Gross energy – (fecal + urinary losses)

Atwater factors (dietary) Gross energy Protein Fat Carbohydrate kcal/g 5. 65 9. 40 4.

Atwater factors (dietary) Gross energy Protein Fat Carbohydrate kcal/g 5. 65 9. 40 4. 10 Digestible energy Protein Fat Carbohydrate 5. 2 9. 0 4. 0 Metabolizable energy Protein Fat Carbohydrate 4 9 4

Body composition Fat mass Triglyceride Fat-free mass Water Protein Mineral Glycogen

Body composition Fat mass Triglyceride Fat-free mass Water Protein Mineral Glycogen

Energy composition Fat mass TRIGLYCERIDE Fat-free mass Water PROTEIN Mineral GLYCOGEN

Energy composition Fat mass TRIGLYCERIDE Fat-free mass Water PROTEIN Mineral GLYCOGEN

Energy density of FAT MASS Animal fat gross energy 9. 45 kcal/g no fecal

Energy density of FAT MASS Animal fat gross energy 9. 45 kcal/g no fecal or urinary loss energy density 9. 45 kcal/g

Energy density of FAT MASS Exception Loss of ketone bodies b-hydroxybutric acid Acetoacetic acid

Energy density of FAT MASS Exception Loss of ketone bodies b-hydroxybutric acid Acetoacetic acid Acetone 4. 96 kcal/g 4. 15 kcal/g 7. 37 kcal/g Starvation (limited data) Losses 10 -20 g/d +100 g dietary CHOH (3 -5% of Elipid) <1 g/d

Energy density FAT-FREE MASS Glycogen = Starch Gross energy 4. 12 kcal/g No urinary

Energy density FAT-FREE MASS Glycogen = Starch Gross energy 4. 12 kcal/g No urinary loss Protein Gross energy Urinary loss Metabolizable 5. 65 kcal/g controversy

Urinary loss associated with protein oxidation Traditional Atwater approach Assume all urinary energy loss

Urinary loss associated with protein oxidation Traditional Atwater approach Assume all urinary energy loss from incomplete protein oxidation. Atwater urine analyses � 7. 9 kcal/g urinary N � 1. 25 kcal/g protein 1 meat diet experiment � 7. 7 kcal/g urinary N � 1. 23 kcal/g De novo calculation Urinary N urea, ammonia, creatinine 90: 5: 5 5. 8 kcal/g urinary N 0. 93 kcal/g

Energy density FAT-FREE MASS Glycogen = Starch Gross energy 4. 12 kcal/g No urinary

Energy density FAT-FREE MASS Glycogen = Starch Gross energy 4. 12 kcal/g No urinary loss Protein Gross energy Urinary loss Metabolizable 5. 65 kcal/g 0. 93 to 1. 23 kcal/g 4. 72 to 4. 42

Energy density FAT-FREE MASS Exceptions Uncontrolled diabetes Glycosuria Up to 150 g/d Starvation N

Energy density FAT-FREE MASS Exceptions Uncontrolled diabetes Glycosuria Up to 150 g/d Starvation N excreted mostly as ammonia Less urinary energy loss from protein oxidation Linked to ketone loss preserve acid/base balance ≈ compensates for energy lost as ketones

Composition of FAT-FREE MASS Water Protein Osseous mineral Non-osseous mineral Glycogen 73% 21% 5%

Composition of FAT-FREE MASS Water Protein Osseous mineral Non-osseous mineral Glycogen 73% 21% 5% 0. 7% Multiple sources because there is not a constant value

Energy density of FAT-FREE MASS Protein Glycogen 0. 21 * (4. 65 -1. 2)

Energy density of FAT-FREE MASS Protein Glycogen 0. 21 * (4. 65 -1. 2) 0. 007*4. 12 FFM: 0. 96 kcal/g Adjust for no bone loss FFM: 1. 0 kcal/g

But do these proportions hold true for the composition of change in weight? TMM

But do these proportions hold true for the composition of change in weight? TMM TBP + CHOH FFM TBW FM FM

Human Experimental Data Weight loss 4 C body composition analysis TBW – D dilution/1.

Human Experimental Data Weight loss 4 C body composition analysis TBW – D dilution/1. 04 TMM – DXA ash*1. 27 Body density by water or air displacement Minimal assumptions Total body water Total mineral mass Protein (+ CHOH) mass Fat mass

Jebb et al Intl J Obesity 31, 756, 2006 48 adult women 24 -65

Jebb et al Intl J Obesity 31, 756, 2006 48 adult women 24 -65 y BMI > 25 kg/m 2 12 w wt loss + 40 follow-up

Jebb et al Intl J Obesity 31, 756, 2006 10 Mass, kg 5 TBP+CHO

Jebb et al Intl J Obesity 31, 756, 2006 10 Mass, kg 5 TBP+CHO 0 0 -12 w (loss) -5 12 -52 w (gain) TBW TMM FM -10 -15 ΔFFM 0. 6 kcal/g 0. 7 kcal/g

Evans et al. Am J Clin Nutr 70: 5, 1999 Women n= 9 in

Evans et al. Am J Clin Nutr 70: 5, 1999 Women n= 9 in each of three groups 21 -40 y 58 -132 kg 27 -44 kg/m 2 Tx 10 wk Control -1000 kcal/d balanced diet Diet + 350 kcal/d moderate Ex

Evans et al. Am J Clin Nutr 70: 5, 1999 4 Mass, kg 2

Evans et al. Am J Clin Nutr 70: 5, 1999 4 Mass, kg 2 0 -2 Con Diet TBP+CHO Diet+Ex TBW TMM FM -4 -6 -8 ΔFFM 0. 6 kcal/g 1. 6 kcal/g 0. 0

Mahon et al. J Nutr Hlth Aging 11: 203, 2007 Women, n=27 postmenopausal 59

Mahon et al. J Nutr Hlth Aging 11: 203, 2007 Women, n=27 postmenopausal 59 + 8 y 77 + 10 kg 29 + 3 kg/m 2 Tx 9 wk 1200 kcal/d balanced diet

Mahon et al. J Nutr Hlth Aging 11: 203, 2007 0 Obese -1 Mass,

Mahon et al. J Nutr Hlth Aging 11: 203, 2007 0 Obese -1 Mass, kg -2 TBP+CHO -3 TBW -4 TMM -5 FM -6 -7 -8 ΔFFM: 0. 8 kcal/kg

Fogelholm et al. Metabolism. 46: 968, 1997 Women, n-32 30 -45 y 94 +

Fogelholm et al. Metabolism. 46: 968, 1997 Women, n-32 30 -45 y 94 + 11 kg 35 + 4 kg/m 2 Tx 12 wk 600 kcal/d (1100 kcal/d final body comp)

Fogelholm et al. Metabolism. 46: 968, 1997 0 Diet -2 Mass, kg -4 TBP+CHO

Fogelholm et al. Metabolism. 46: 968, 1997 0 Diet -2 Mass, kg -4 TBP+CHO -6 TBW TMM -8 FM -10 -12 -14 ΔFFM: 4. 2 kcal/kg

Myint et al, Obesity, 18: 391, 2010 Otherwise healthy M: F 4: 7 42

Myint et al, Obesity, 18: 391, 2010 Otherwise healthy M: F 4: 7 42 +14 y 31 + 1 kg/m 2 Heart failure (excess TBW) M: F 3: 8 54 +10 y 38 + 5 kg/m 2 Tx 8 wks 600 kcal/d deficit

Myint et al, Obesity, 18: 391, 2010 2 Baseline Wt = 96 & 113

Myint et al, Obesity, 18: 391, 2010 2 Baseline Wt = 96 & 113 kg 0 Mass, kg -2 Obese -4 Obese+ Heart Failure TBP+CHO+TMM -6 TBW FM -8 -10 -12 -14 ΔFFM: ? ? 0. 9 kcal/g

Energy Density DFAT-FREE MASS 2 • 4. 2 kcal/g 1. 5 1 0. 5

Energy Density DFAT-FREE MASS 2 • 4. 2 kcal/g 1. 5 1 0. 5 0 Median 0. 7 kcal/g SEM 0. 5 kcal/g

Other relationships • 1. 9 Weight Fraction 1 0. 8 0. 6 0. 4

Other relationships • 1. 9 Weight Fraction 1 0. 8 0. 6 0. 4 0. 2 Median 0. 18 Median 0. 14 0 DFFM/DWt (DP+C)/DFFM

Why so variable? Problem of propagation of error and small changes M/Db = Mtbw/Dtbw

Why so variable? Problem of propagation of error and small changes M/Db = Mtbw/Dtbw + Mtmm/Dtmm +Mpro/Dpro + Mfm/Dfm

Why so variable? Problem of propagation of error and small changes M/Db = Mtbw/Dtbw

Why so variable? Problem of propagation of error and small changes M/Db = Mtbw/Dtbw + Mtmm/Dtmm + Mpro/Dpro + Mfm/Dfm And Mpro = M – Mtbw – Mtmm - Mfm

Why so variable? Problem of propagation of error and small changes DTBW sd =

Why so variable? Problem of propagation of error and small changes DTBW sd = 0. 4 kg Pro + CHOH �D 0. 4 kg/10 kg wt loss, �sd = 0. 4+kg �If n = 100, then SEM = 0. 04 kg

4 C approach cannot detect differences in energy density of DFFM without a large

4 C approach cannot detect differences in energy density of DFFM without a large n, but the median is meaningful.

Conclusions Energy density of FM 9. 45 kcal/kg High level of confidence Energy density

Conclusions Energy density of FM 9. 45 kcal/kg High level of confidence Energy density of FFM 1. 0 kcal/g High level of confidence in theory Modest level of confidence in practice