Download Slides only - Graduate Training Program in Space Life Sciences

Functions of Nutrition in Space
Scott M. Smith, Ph.D.
Nutritionist
Manager for Nutritional Biochemistry
NASA Johnson Space Center
PhD Program in Space Life Science
Nutritional Biochemistry Lab – NASA/JSC
 Charge: determine the
nutritional requirements
for extended duration
space flight
 Calorie requirements
 Vitamin A, E, and D,
Calcium, Iron, and Zinc
Courtesy of NASA
PhD Program in Space Life Science
Functions of Nutrition in Space
 Meet energy / nutrient
requirements
 Psychosocial aspects of the
food system
 Nutrition as a
countermeasure
 Changes in the diet to
mitigate negative effects of
space flight
 Importance of defining the
nutritional requirements for
crews before departure
PhD Program in Space Life Science
Concerns: Nutrition in Space Flight
 Nutrient Requirements





Energy
CHO (fiber), Fat, Protein
Fat-soluble vitamins
Water-soluble vitamins
Minerals, Fluid
 Systems
 Bone, Muscle, Cardio
Fluid/Electrolyte
 Immunology
 Hematology, Neurology
 Endocrine, Behavioral
health & performance,
Gastrointestinal
 Countermeasures
 Energy, Amino acids,
Protein, Sodium
 Fatty acids
 Antioxidants, Vitamin D
 Bisphosphonates, K-Citrate
 Medications, Exercise
 Other
 Vehicle/Mission
 Food System, Duration
 Radiation, extra vehicular
activity
 Schedule
PhD Program in Space Life Science
Energy
Energy intake across different space programs
% WHO predicted
 Food intake is one of the
primary challenges in
space
 Dietary intake across the
space programs
 Percent of World Health
Organization predicted
energy requirement
 Crew members can meet
their nutritional
requirements through
food while in space
110
100
90
80
70
60
50
40
30
20
10
0
Apollo
Sk ylab
Shuttle
M ir
E1-4
E5-13
Adapted from Smith, SM, 2005, 2008
PhD Program in Space Life Science
Energy
 Excess loss of
10% body
mass
 Other effects:
 Fluid shift
 Salt loading
 Emesis
10
%  from Preflight
 Percent of body
weight loss at
the end of a
mission
 Effects of long
duration flights:
5
0
-5
-10
-15
0
20
40
60
80
100
120
140
160
180
200
220
Mission Duration (days)
Each symbol is a difference crew member
Adapted from Kloeris, LH, 2007
PhD Program in Space Life Science
Question From the Audience
Are these weights measured after attempts
are made to restore plasma volume
to normal levels?
PhD Program in Space Life Science
Energy
 Excess loss of
10% body
mass
 Other effects:
 Fluid shift
 Salt loading
 Emesis
10
%  from Preflight
 Percent of body
weight loss at
the end of a
mission
 Effects of long
duration flights:
5
0
-5
-10
-15
0
20
40
60
80
100
120
140
160
180
200
220
Mission Duration (days)
Each symbol is a difference crew member
Adapted from Kloeris, LH, 2007
PhD Program in Space Life Science
Energy
 Likely consequences of
poor food intake
 Fair/poor function of
cardiovascular system
 Loss of muscle mass
 Loss of bone mass
 NTX (urinary Ntelopeptide)
 PICP (serum type I
procollagen carboxyterminal propeptide)
 OC (plasma osteocalcin)
Reproduced from J Bone Miner Res 2004;19:1231-1240 with
permission of the American Society for Bone and Mineral
Research
PhD Program in Space Life Science
Energy: Case Study
150
5
100
0
50
-5
Energy intake
Body Mass
(%  from preflight)
Energy Intake
(% WHO)
Dietary intake record using Food Frequency Questionnaire
Body Mass
0
0
50
100
150
Courtesy of NASA
Food Frequency Questionnaire
-10
200
Day of Flight
Adapted from Smith, SM, 2005
PhD Program in Space Life Science




25 (OH) Vitamin D
Elderly individuals
Average age: 77 years
Consequences of poor
Vitamin D intake below
25 nmol/L
 Rickets, Osteomalacia
 U.S. Astronauts
 Pre and Post flight
 4-6 months on board ISS
 Increased incidence of
disease between 25-80
nmol/L
25 (OH) Vitamin D
(nmol/L)
Consortium for Research in Elder
Self-Neglect (SN) of Texas (CREST) Study
110
100
90
80
70
60
50
40
30
20
10
0
SN
Control
Elderly
Individuals
Pre
Post
Astronauts
Adapted from Smith, SM, 2005, 2006
PhD Program in Space Life Science
Bone and Beyond
 Parathyroid Hormone
(PTH) is normalized
when Vitamin D is
above 80 nmol/L
 The higher Vitamin D
the lower the PTH
levels
Reproduced from New England Journal of Medicine.
338(12):777-783, 1998. Copyright © 1998. Massachusetts
Medical Society. All rights reserved.
PhD Program in Space Life Science
Bone and Beyond
 Vitamin D status has been related to:






Fracture risk and Bone Mineral Density
Muscle strength/function, falls
Cancer (prostate, breast, colon)
Multiple sclerosis
Blood pressure/heart disease
Diabetes (type 1)
PhD Program in Space Life Science
Recommendations
 Optimal Vitamin D status:
 25D levels ≥ 80 nmol/L
 Vitamin D sources:
 Foods
 Fortified milk, orange juice
 Fish (e.g., salmon, tilapia,
tuna)
 Few other sources of Vitamin
D
 Sunlight
 UV conversion of 7dehydrocholesterol to
previtamin D3 in the skin
 Supplements
PhD Program in Space Life Science
Polar Vitamin D Study in Antarctica
Antarctica
 Blind supplementation study
 4 groups in the study randomized:




400 IU Vit. D
1000 IU Vit. D
2000 IU Vit. D
Individuals who
 did not take the
supplements but
provided samples or
 took their own Vit. D
supplements
Courtesy of NASA
PhD Program in Space Life Science
Bone Loss in Space
 Hyperresorptive bone loss
 Running on the treadmill does
nothing for bone health in
space
 Nutrition is a countermeasure
against bone loss
Courtesy of NASA
Credit:: NASA
PhD Program in Space Life Science
Nutrition and Bone
1750
Courtesy of NASA
1500
NTX (nmol/d)
 Dietary protein has a
significant impact on
bone health
 Higher ratio of animal
protein to potassium in
the diet provide more
acid precursors
 An increased ratio leads
to more bone
breakdown
 NTX (N-telopeptide)
 APro/K (ratio of animal
protein intake to
potassium intake)
1250
1000
750
500
250
0
r = 0.80*
0.50
0.55
0.60
0.65
0.70
0.75
APro/K (g/mEq)
Adapted from Zwart, SR, 2004
PhD Program in Space Life Science
Nutrition and Bone
 Pilot Study: Antioxidant
countermeasure to mitigate
oxidative damage
 Treatment: Grape juice, Vitamin
E & 0.5 mg NAC every day for 2
weeks
 N-acetylcysteine (NAC) contains
cysteine, a sulfur containing
amino acid
 Metabolism increases acid load
which affects bone
 N-telopeptide (NTX) - marker of
bone resorption
 50% increased excretion in bed
rest subjects, 100% increased
excretion for astronauts
 6 subjects – healthy astronauts
 2 weeks placebo: no change in
N-telopeptide
 2 weeks: Grape juice, Vitamin
E & 0.5 mg NAC/day
 Increased excretion of bone
markers identical to bed
rest subjects
PhD Program in Space Life Science
Nutrition and Bone
 Space flight diet is high in
sodium
 5-8 grams Na/day
 C-telopeptide (CTX) –
marker of bone breakdown
 Low Na+ diet before and
during bed rest
 ~50% increase in CTX
 High Na+ diet during bed
rest
 Na+ associated with pH
 High Na+ load leads to
acid that has negative
effect on bone
Courtesy of NASA
Unpublished data, graph not displayed
PhD Program in Space Life Science
 Estimated by measuring
Vit. K status undercarboxylated
osteocalcin (Uosteocalcin)

Vit. K = Uosteocalcin
20
Day 1-85
UOsteocalcin (%)
 Related to synthesis of
gamma-carboxyglutamic
acid residues in proteins
25
15
10
5
Courtesy of NASA
Day 131-179
 Vitamin K influence on
bone
Day 86-130 (Vitamin K)
Nutrition and Bone
0
Pre
Mission
Post
Adapted from Vermeer, C, 2004
PhD Program in Space Life Science
Nutrition and Bone
 Sources: spinach, salmon
 Relationship between omega3’s and bone
 Could mitigate cancer risk,
muscle loss and bone loss
Day 1-85
20
15
10
5
Courtesy of NASA
Day 131-179
 Omega-3 fatty acids
25
UOsteocalcin (%)
 1 astronaut before and after
flight
 After 85 days Uosteocalcin
goes up without
supplementation of Vit. K
 With Vit. K supplementation
Uosteocalcin goes down.
Day 86-130 (Vitamin K)
 European Data on MIR
0
Pre
Mission
Post
Adapted from Vermeer, C, 2004
PhD Program in Space Life Science
Iron and Oxygen
Courtesy of NASA
Adapted from Smith, SM, 2004
 marker for oxidative damage
to DNA
 Increased after flight and
NEEMO
 Radiation/oxygen issues
have implications for
cataracts and other health
issues.
20
15
10
5
0
0
200
400
600
800
1000
Days of flight
Adapted from Smith, SM, 2001, 2004
150
8(OH)dG (%  )
 Iron storage increases during
flight
 Urinary 8-hydroxy guanosine
Body iron (mg/kg)
25
100
50
Credit: NASA
0
Mir
ISS
NEEMO
PhD Program in Space Life Science
Iron and Oxidative Damage
The more total
body iron the more
oxidative damage
Courtesy of NASA
Unpublished data not displayed
PhD Program in Space Life Science
Bed Rest
 Changes in iron
metabolism during bed
rest.
 Transferrin receptors go
down during bed rest
suggesting excess iron
 Total body iron vs.
8(OH)dG
Courtesy of NASA
Unpublished data not displayed
PhD Program in Space Life Science
40
20
0
R
+6
D
9/
1
R 1
+0
M
7
-20
M
D
6/
 Total body iron increases
 Malonaldehyde increases –
marker of oxidative damage
 Inverse relationship between
total body iron and SOD –
seen with iron overload
 Iron excess is related to
oxidative damage.
60
Pr
e
 Hyperbaric environment
Total body iron (%  )
 NEEMO analogue
80
Adapted from Zwart, SR, 2008
150
MDA (% )
NEEMO –
oxidative damage
100
50
0
Courtesy of NASA
+6
R
D
9/
1
R 1
+0
M
6/
7
D
M
Pr
e
-50
PhD Program in Space Life Science
Space Suit
 Peggy Whitson - extra
vehicular activity (EVA)
suit
 Provides thermal
protection
 Reduced pressure
environment
Courtesy of NASA
PhD Program in Space Life Science
First Blood & Urine Samples on ISS
 Vitamin D levels
before & after flight
 Flight day 15 to
flight day 80 – levels
hold
 800 IU/day of Vitamin
D is recommended
Courtesy of NASA
Unpublished
data not
displayed
PhD Program in Space Life Science
Cape Canaveral – Kennedy Space Center
Courtesy of NASA
PhD Program in Space Life Science