Question

Can someone please explain to me how my instructor came up with this answer?

Consider the following question You are responsible to assess and plan diet in a nursing home with 100 elderly residents. The table below shows their intakes of vitamin B12 Vitamin B12 intake (ug) No. of people <1.6 5 1.6-1.7 20 1.8-1.9 20 2.02.1 30 2.2-2.3 2.472.5 155 >= 2.6 5 EAR for B12 is 2.0 ug and RDA is 2.4 ug. What is the prevalence (% of people) of inadequate B12 intake in this population? Prevalence 5+5+20 100 - = 45% of inadequacy

Answer 1

EAR- Estimated Average Requirement

RDA- Recommended Dietary Allowance

Given, The EAR for Vitamin B12 is 2.0 microgram and RDA is 2.4 microgram.

Prevalence= No. of people affected by it/ Total number of population

Hence, No. of people consuming insufficient Vitamin B12 Would be all the elderly residents in the nursing home who consume less than 1.6 mcg, 1.6-1.7 mcg and more than or equal to 2.6 mcg of Vitamin B12; which would be 5, 20 and 5 respectively.

Total population of the elderly residents in the nursing home= 100

Prevalence of inadequate Vitamin B12 consumption= 5+20+5/100= 0.3= 30%

NOTE= as you've stated in the question above that 20+5+5/100= 45% is mathematically wrong. It would give you 0.3 which when converted in % form would become, 30%.

However, Your statement above has not included people who consume Vitamin B12 between 1.8-1.9 mcg, which falls below the EAR and hence, also inadequate.