BMI and protein energy malnutrition Flashcards
BMI is an indicator of
body fat
BMI is measured by
weight in kg/ (height in metres)^2
BMI <18.5 is
underweight
Underweight BMI is
<18.5
BMI 18.5-25 is
normal weight
Normal weight BMI is
18.5-25
BMI 25-30 is
overweight
Overweight BMI is
25-30
Obesity BMI is
> 30
BMI >30 is
obese
Morbid obese BMI is
> 40
BMI >40 is
morbidly obese
protein-energy malnutrition (PEM) exists when
there is inadequate intake of macronutrients
The two divisions of protein-energy malnutrition are
kwashiorkor (protein lack) and marasmus
Protein-energy malnutrition can also exist in the context of
eating disorders
What does an optimum diet provide in terms of vitamins and minerals?
a variety of foods to provide vitamins (mostly vegetable) and enough meat to provide iron
Low risk body percent fat for men is
14-20%
Low risk body percent fat for women is
18-30%
Body fat can be estimated by
caliper measurements of skinfold thickness; body density measurements by immersion in water (hydrodensitometry); bioelectric impedance (fat = better electrical insulator)
Energy needed per day is
132kJ/kg lean body mass
Increased risk of metabolic complications is associated with what waist circumference?
over 94 cm for men, over 80cm for women
Substantially increased risk of metabolic complications is associated with what waist circumference?
over 102cm for men, over 88cm for women
What is protein sparing?
when enough energy is provided by carbohydrate and fat for protein to be used structurally and not for gluconeogenesis
Long-term starvation has what affect on the gut?
intestinal villi degenerate because there is nothing to absorb; the gut digests itself, which complicates refeeding
What is kwashiorkor?
protein lack where energy intake may be adequate; causes oedema (aflatoxin from aspergillus fungus in the diet produces an epoxide via p450 that kills guanine in DNA; causes cell death in the liver and reduced serum albumin = pot belly) with maintenance of some subcutaneous fat tissue
What is marasmus?
nutrient lack and energy insufficient; skin and bones appearance with little or no subcutaneous fat tissue
Lack of thiamin in starvation leads to
digestive, visual, physical, and neurological disabilities even on refeeding
Negative nitrogen balance occurs when
more is excreted than consumed; in starvation, post burns victims, postp-op patients, and AIDS patients
What is cachexia?
extreme example of the loss of muscular and adipose tissue in terminal illness; caused in part by high levels of TNFa
What causes lactose intolerance?
in non-dairy consuming societies lactase production drops 90% in the first 4 years of life (populations that drink milk have mutations on chromosome 2 that prevent this reduction in lactase)
Vegans risk deficiencies in
B12 (peripheral neuritis, pernicious anaemia), vitamin D, riboflavin, iron, calcium, and zinc
