FNH 355 - Malnutrition II

Describe an example of a current action to combat iodine deficiency.

Iodine has been added to household (NaCl) salt for 2/3 of world's households, reducing the prevalence of iodine deficiency from 30% to 15%.

Describe two physical signs/symptoms associated with iodine deficiency

1. Cretinism: severely stunted physical and mental growth due to maternal hypothyroidism 2. Goiter: swelling of thyroid gland (condition develops during adulthood)

Name four advantages of micronutrient powder packets.

1. Easy to use 2. Highly acceptable 3. Can be added to any soft cooked food 4. Sprinkles are encapsulated in lipid: prevents transfer of taste to other food

What can be done at the community/national level to combat iron deficiency?

1. Education and awareness 2. Fortification and supplementation - industrial or household - industrial fortification of a staple such as wheat flour - micronutrient packets 3. Control malaria, hookworm, and other infections - public sanitation - malaria nets

What does zinc deficiency contribute to?

1. Growth failure and weakened immunity to children 2. Increased child mortality rates as a result of diarrhoea, pneumonia, malaria

What can be done to combat vitamin A deficiency?

1. Increase dietary sources of vitamin A (immediate cause) - promote breast feeding (breast milk contains vitamin A) - promote consumption of available foods e.g. palm oil, greens 2. Local (household, community) food production (underlying cause) 3. Education and awareness: target women (underlying cause) 4. Increase distribution of vitamin A supplements (basic cause) 5. Fortification (basic cause)

What are some causes of iron deficiency?

1. Low dietary intake due to poverty, etc. (immediate cause) 2. Poor absorption (immediate cause): examples include diarrhoea, iron less bioavailable in plant foods (due to presence of inhibitors such as phytate) 3. Infections e.g. malaria, HIV/AIDS, hookworms, schistosomiasis, tuberculosis (underlying/basic causes)

Who are most at risk of developing vitamin A deficiency?

1. People who live in poverty 2. Populations in which rice provides bulk of daily diet 3. Can occur at any age, but at greatest risk: children under the age of five 4. Pregnant and lactating women: have higher vitamin A requirements

What are the consequences of VAD?

1. Xeropthalmia (night blindness, conjunctival xerosis, Bitot's spots, corneal xerosis, ulceration, necrosis/keratomalacia) 2. Compromised immunity (mucous barriers not as effective, immune response impaired) 3. Increased infection: predisposes individuals to severe infection e.g. measles (50% mortality rate), respiratory infection, infectious diarrhoea, dysentery, HIV/malaria 4. Increased morbidity and mortality 5. Stunted linear growth

What are the consequences of iron deficiency in children and in adults?

Children: - premature birth, low birth weight, increased risk of infections, death, impaired physical growth - impaired cognitive development, negative impact on learning Adults: - reduced productivity (iron deficiency lowers productivity of workforces, with an estimated losses of 2% of GDP in worst-affected countries) - increased likelihood of death during childbirth (IDA contributes to 20% of all maternal deaths)

Animal tissue contains 60% heme iron and 40% non-heme iron (T/F).

FALSE: Animal tissue contains 40% heme iron and 60% non-heme iron.

Eggs contain both Heme and non-Heme iron (T/F).

FALSE: Eggs and milk-based products contain non-Heme iron only. Heme iron is only found in tissue and blood

Vitamin A supplement at birth is associated with fewer cases of measles, and less severe cases in both boys and girls (T/F).

FALSE: Vitamin A supplement at birth is associated with fewer cases of measles, and less severe cases if they occurred in boys, but not girls

Fortification of sugar, oil, and margarine alone will solve the problem of vitamin A deficiency (T/F).

FALSE: fortification needs to be combined with other strategies (e.g. supplementation) to be successful.

Non-Heme iron is only found in plant foods (T/F).

FALSE: non-heme iron is found in both animal and plant foods

On average, 1000 kcal of a mixed diet provides 14 mg of iron (T/F)

FALSE: on average, 1000 kcal of a mixed diet provides 6 mg of iron

Sugar, oil, margarine and green leafy vegetables have all been successfully fortified with vitamin A (T/F).

FALSE: only sugar, oil, and margarine have been fortified with vitamin A

The bioavailability of iron from a vegan diet is estimated to be the same as that of an omnivorous diet, which is 14-18% (T/F).

FALSE: the bioavailability of iron from a vegan diet is estimated to be ~10% versus 14-18% for an omnivorous diet.

To be successful, fortified food should provide at least 30% of the daily kcal intake for the target group (T/F).

FALSE: to be successful, fortified food should provide at least 15% of the daily kcal intake for the target group.

Typically, we absorb 14-18% of iron from diet, irrespective of our iron status (T/F).

FALSE: typically, we absorb 14-18% of iron from the diet, but if iron status is low, we can absorb up to 30-40%

List the factors that increase and reduce the absorption of iron.

Factors that increase absorption: vitamin C, MFP factor Factors that reduce absorption: phytates, oxalates; polyphenols, fibre, calcium, zinc, EDTA

What can be done at the individual level to combat iron deficiency?

Increase iron intake and absorption (immediate cause) - dietary diversification - increase enhancers, and reduce inhibitors of iron absorption e.g. consume vitamin C at same time as consume non-heme iron sources - include iron-rich foods - cook with cast iron

What is the recommended daily amount of iron for males and females? What about for vegetarians?

Males, Females: 8, 18 mg For vegetarians, need 1.8x more iron (14, 32 mg)

What do the terms "microcytic" and hypochromic" mean in the context of iron deficiency anemia?

Microcytic: small size compared to size of lymphocyte nucleus Hypochromic: pale (pale centre is more than 1/2 the diameter of the cell)

Give an example of a current action to combat zinc deficiency

Research has shown that zinc supplements can help treat diarrhoea and reduce diarrhoeal mortality by 50%. WHO recommends 10-14 days zinc supplementation with diarrhoea episode - but this recommendation has not been widely adopted due to practical considerations.

Iodine deficiency is a major preventable cause of impaired cognitive development worldwide (T/F).

TRUE

The proportion (%) of iron absorbed is lower when the dietary intake of iron is higher (T/F).

TRUE

Explain two methods by which dietary intake of vitamin A could be increased.

a. Selective breeding: breed maize varieties with high beta-carotene content - estimated could provide 50% of average daily vitamin A requirement - challenges (e.g. in Zambia): white maize is preferred; maize is viewed as "drought food" because it was often distributed as food aid b. Golden rice: genetically engineered variety of rice containing beta-carotene - estimated could provide 65-80% of average daily vitamin A requirement - plethora of ethical issues surrounding GMOs