BODY COMPOSITION Flashcards
DEFINITION OF BODY COMPOSITION?
THE RELATIVE PROPORTION OF PROTEIN, FAT, WATER AND MINERAL COMPONENTS IN THE BODY THAT MAKE UP TOTAL BODY WEIGHT
IS THE TERM WEIGHT OR MASS MORE ACCURATE?
MASS
MEASUREMENTS RELATED TO BODY COMPOSITION ARE CALLED?
ANTHROPOMETRIC MEASUREMENTS
WHEN IS THE FAT COMPOSITION OF THE BODY THE HIGHEST?
AT 1 Y.O.
IS THE PERCENTAGE OF BONE THE SAME IN MEN AND WOMEN + THE NUMBERS?
YES, 12%
PERCENTAGE OF MUSCLE TISSUE MEN VS WOMEN?
45 VS 36
ESSENTUAL FAT PERCENTAGE MEN VS WOMEN?
3 VS 12
NON ESSENTIAL FAT % MEN VS WOMEN?
12 VS 15
IS THERE A BIGGER DIFFERENCE IN ESSENTIAL OR NON-ESSENTIAL FAT STORAGE BETWEEN MEN AND WOMEN?
ESSENTIAL
WHAT ARE THE 2 TYPES OF BODY SHAPES ACCORDING TO LOCATION OF FAT DEPOSIT?
ANDOID (APPLE); DISTRIBUTION OF FAT ON THE UPPER BODY (STOMACH), USUALLY FOUND IN MALES
GYNOID (PEAR); DISTRIBUTION OF FAT ON THE LOWER BODY (HIPS) USUALLY FOUND IN WOMEN
GYNOID BODY SHAPE IS MORE COMMON IN WHICH SEX?
FEMALE
WHAT ARE THE CELLS COMPOSING ADIPOSE TISSUE CALLED?
ADIPOCYTES
THE 2 TYPES OF ADIPOSE TISSUE DEPENDING ON ITS LOCATION?
SUBCUTANEOUS ADIPOSE TISSUE (SAT); BENEATH THE SKIN
VISCERAL ADIPOSE TISSUE (VAT); LINING THE INTERNAL ORGANS
WHICH TYPE OF ADIPOSE TISSUE HAS A STRONGER ASSOCIATION WITH INSULIN RESISTANCE, T2D, HYPERTENSION, HYPERLIPIDEMIA AND CVD?
VISCERAL ADIPOSE TISSUE
WHICH BODY SHAPE IS ASSOCIATED WITH INCREASED RISK OF JOINT DISORDERS?
GYNOID
WHICH BODY SHAPE IS ASSOCIATED WITH INCREASED RISK OF CVD AND METABOLIC DISORDERS?
ANDOID
WHAT IS THE MOST FREQUENTLY USED MEASURE OF OBESITY?
BODY WEIGHT
LIMITATIONS TO MEASURING WEIGHT ONLY WHEN ASSESSING DISEASE RISK?
- VARIETY OF SCALES ARE AVAILABLE, NOT ALWAYS ACCURATE
- CHANGES IN WEIGHT CORRESPOND TO CHANGES IN BODY WATER, FAT AND/ OR LEAN TISSUE
- BODY WEIGHT TAKEN WITHOUT MEASUREMENGTS CAN BE MISLEADING
WHAT IS THE MOST COMMON OF THE NUTRITION SCREENING TOOLS TO ASSESS RISK OF DISEASE WITH UNDER OR OVER NUTRITION?
BMI; BODY MASS INDEX
EQUATION FOR CALCULATING BMI?
BMI=MASS (KG)/HEIGHTXHEIGHT (M2)
NORMAL BMI?
18.5-24.9
WEIGHT CHANGE OF HOW MUCH KG IS NEEDED TO PRODUCE A UNIT CHANGE IN BMI?
3.5 KG
LIMITATIONS OF USING BMI AS INDICATION OF UNDER OR OVER NUTRITION DISEASE RISK?
- DIFFERENT BODY COMPOSITIONS HAVE A SIGNIFICANT EFFECT ON HEALTH AND PEOPLE WITH SAME BMI MIGHT HAVE COMPLETELY DIFF RISK LEVELS
- BMI IS NOT A STRAIGHTFORWARD INDEX BECAUSE OF GROWTH
- NEED TO BE CAUTIOUS WHEN MEASURING BMI OF ATHLETES AND PEOPLE WITH CERTAIN MEDICAL CONDITIONS, LIKE SARCOPENIA WHERE BODY WEIGHT MIGHT BE ALTERED SIGNIFICANTLY BY CHANGING PROPORTIONS OF MUSCLE AND FAT MASSES
- DOES NOT PROVIDE INFO ABOUT BODY COMPOSITION
WHY IS BMI NOT RELIABLE FOR CHILDREN?
BECAUSE OF GROWTH
WHICH ABDOMEN TO HIP RATIO REPRESENTS CENTRALISED DISTRIBUTION OF FAT AND INCREASED RISK FOR CVD, DIABETES, CANCER?
WOMEN: >0.85
MEN: >1.0
WHAT ARE SKIN FOLD MEASUREMENTS USED FOR AND WHERE/HOW ARE THEY TAKEN?
- USED TO GIVE AN ESTIMATE OF THE TOTAL VOLUME OF SUBCUTANEOUS (ADIPOSE) FAT
- TAKEN FROM THE ARM, WAIST AND LEG, ALL FROM THE SAME SIDE OF THE BODY
WHAT IS HAND GRIP USUALLY USED FOR AND WHY CAN MEASURING IT BE HELPFUL IN NUTRITION?
- USUALLY USED TO MEASURE UPPER BODY STRENGTH
- CAN BE A GOOD INDICATOR OF NUTRITIONAL STATUS BECAUSE MUSCLE FUNCTION RESPONDS EARLIER TO NUTRITIONAL DEPRIVATION THAN MUSCLE/BODY MASS AS ENERGY STORES ARE QUICKLY DEPLETED
- CAN BE USED AS A LONG TERM PREDICTOR OF MORTALITY, DECREASING GRIP IS ASSOCIATED WITH INCREASES IN ALL CAUSES OF MORTALITY
WHAT IS BIOELECTRICAL IMPEDANCE ANALYSIS (BIA)?
ANALYSIS OF BODY COMPOSITION THAT PRODUCES ESTIMATES OF TOTAL BODY WATER (TBW), FAT FREE MASS (FFM) AND FAT MASS
- DONE BY MEASURING THE RESISTANCE OF THE BODY AS A CONDUCTOR TO A VERY SMALL ALTERNATING ELECTRICAL CURRENT
- BASED ON THE FACT THAT FAT IS NON-CONDUCTIVE
- PROPORTIONAL TO THE VOLUME OF TOTAL WATER
WHAT IS THE BASIS FOR THE BIOELECTRICAL IMPEDANCE ANALYSIS (BIA)?
THE FACT THE FAT IS NON CONDUCTIVE
WHAT IS THE BIOELECTRICAL IMPEDANCE INDEX PROPORTIONAL TO?
VOLUME OF TOTAL WATER
LIMITATIONS OF BIOELECTRICAL IMPEDANCE ANALYSIS (BIA)?
- NOT APPLICABLE TO OVERWEIGHT OR OBESE CHILDREN OR ADULTS
- PROVIDES INFO ON BODY COMPOSITION BUT NOT BODY FAT DISTRIBUTION
- A LOT OF FACTORS INFLUENCE CURRENT FLOW, E.G. TEMPERATURE, EXERCISE, EXTREME OBESITY OR THINNESS…
WHAT IS DENSITOMETRY AND WHAT ARE THE LIMITATIONS?
- TRADITIONALLY MEANT HYDROSTATIC WEIGHING
- SUBJECT TOTALLY SUBMERGED AND ASKED TO BREATHE OUT IN ORDER TO GAIN AN IDEA ABOUT BODY COMPOSITION AND PERCENTAGE OF BODY FAT
- NOT SUITED FOR THE YOUNG, ELDERLY OR ILL
- HIGHLY SENSITIVE TO CHANGES IN WATER TEMP AND BONE MASS
- NEEDS TO BE REPEATED SO THE PERSON NEEDS TO BE REPEATEDLY DUNKED
3 DIRECT METHODS OF MEASURING BODY COMPOSITION:
- DUAL ENERGY X-RAY ABSORPTIOMETRY (DXA OR DEXA)
- COMPUTED TOMOGRAPHY (CT)
- MAGNETIC RESONANCE IMAGING (MRI)
WHAT IS THE MOST POPULAR METHOD FOR QUANTIFYING FAT, LEAN AND BONE TISSUES?
DUAL ENERGY X RAY ABSORPTIOMETRY (DEXA)
DEXA (DUAL ENERGY X RAY ABSORPTIOMETRY):
- ALLOWS A WHOLE IMAGING OF THE BODY
- ALLOWS THE DISCRIMINATION OF TOTAL BODY ADIPOSE AND SOFT TISSUE, IN ADDITION TO BONE MINERAL CONTENT AND BONE MINERAL DENSITY
- FAST (10-20MINS)
- LITTLE RADIATION
- MATHEMATICAL ALGORITHMS DO THE CALCULATION OF SEPARATE COMPONENTS
DEXA DURATION?
10-20MINS
LIMITATIONS OF DEXA?
- NOT VERY RELIABLE IN EXTREME POPULATIONS, E.G. THE OBESE
- AFFECTED BY DIFFERENCES AMONG MANUFACTURERS IN THE TECHNOLOGY, MODELS AND SOFTWARE EMPLOYED..
DIFFERENCE BETWEEN CT AND MRI?
CT USES X RAYS TO PRODUCE AN IMAGE WHILE MRI USES STRONG MAGNETS AND RADIO WAVES
CT VS MRI, WHAT IS MORE COMMON, CHEAPER AND MORE DETAILED/RELIABLE?
CT LESS EXPENSIVE AND MORE COMMON
MRI MORE DETAILED
WHICH TISSUES WILL THE MRI SHOW A PARTICULARLY DETAILED IMAGE OF COMPARED TO CT?
SOFT TISSUES
WHICH TECHNIQUES ARE USED TO ASSESS/IMAGE FATS THAT HAVE INFILTRATED THE MUSCLE OR THE LIVER?
CT AND MRI
DEXA, MRI AND CT SCANS ARE COMBINED IN RESEARCH. WHAT DOES EACH TYPE THEY BEST ASSESS?
DEXA EVALUATES BODY COMPOSITION
MRI AND CT EVALUATE FAT DISTRIBUTION
WHICH IMAGING METHOD IS OFTEN USED TO MEASURE BONE DENSITY?
DEXA