Vitamin A deficiency: migrant health guide
- Public Health England
- Part of:
- Non-communicable health concerns: migrant health guide
- First published:
- 31 July 2014
Advice and guidance on the health needs of migrant patients for healthcare practitioners.
Vitamin A deficiency is extremely rare in people born in the UK, but is a serious public health concern in many low income countries, particularly in Africa and South East Asia.
Vitamin A deficiency affects young children and pregnant women from low-income countries most.
Consider vitamin A deficiency in at-risk migrant patients. Where you suspect it, seek advice on appropriate diagnosis and management from your local endocrinology or paediatric team.
Consider vitamin supplementation for all infants from 1 month to 5 years, especially in at-risk groups. Low-income families in the UK who receive one of a range of income-related benefits or Child Tax Credits may qualify for Healthy Start. Those who may also qualify for free Healthy Start vitamin supplements are:
- pregnant women
- women with a child under 1 year old
- children between 6 months and 4 years old
The supplements for children contain vitamin A.
However, advise pregnant women or women who may become pregnant to avoid vitamin A supplementation and foods rich in vitamin A, such as liver and liver based products, because vitamin A has teratogenic effects in overdose.
WHO estimates that the number of people who are biochemically vitamin A deficient amounts approximately to:
- one-third of the world’s preschool children
- 15% of pregnant women
The number of people who are night blind as a result is:
- 1% of all children
- 8% of all pregnant women
The main cause of vitamin A deficiency globally is a diet that is chronically deficient in the vitamin. Conditions associated with chronic diarrhoea can also reduce vitamin A absorption. Furthermore, chronic or repeated infections can deplete physiological supplies. These factors may co-exist in people who are socio-economically disadvantaged.
Vitamin A is an essential nutrient needed in small amounts. 0.7mg a day for men, 0.6mg a day for women ensures:
- normal functioning of the visual system
- maintenance of cell function for growth and development, epithelial integrity (skin and mucous membranes), red blood cell production, immunity and reproduction
Some research suggests that having more than an average of 1.5mg per day of vitamin A over many years may affect bone health and make them more likely to fracture as people get older.
Forms of vitamin A
Vitamin A is found in 2 forms: retinol and carotenoids.
Retinol occurs in foods from animal sources, such as:
- whole eggs
In the UK fat spreads are also fortified with retinol.
Carotenoids (mainly beta-carotene) occur in plant sources which are converted to retinol in the body, for example:
- green leaves
- ripe mangos
- other orange-yellow vegetables and fruits
Deficiency may be subclinical, with those at risk including:
- premature infants
- infants who are exclusively breastfed by vitamin A deficient mothers
- recent migrants or refugees from low-income countries that have a high incidence of vitamin A deficiency and/or infectious disease
- children living at or below the poverty level
- children with inadequate health care or immunisations
- children living in areas with known nutritional deficiencies
Clinical deficiency has numerous health consequences, and infants, children and pregnant women are most at risk as demands for vitamin A are higher during growth and pregnancy, including:
- xerophthalmia, the leading preventable cause of blindness in children globally
- night blindness, especially during pregnancy when the additional metabolic demands cannot be met by a pre-existing marginal maternal vitamin A status
- increased severity of infections
- susceptibility to infections
- failure to thrive
Be alert to the possibility of vitamin A deficiency in at-risk migrant patients.
Testing and treatment
Serum retinol is not useful for assessing the vitamin A status of individuals as it is not always correlated with intake or clinical signs of deficiency. Serum retinol is homeostatically controlled, unless liver vitamin A stores are either:
- severely depleted (<0.70 μmol/l)
- very high (>1.05 μmol/l).
In population studies however, the distribution of serum retinol values and the prevalence of individuals with serum retinol values below 0.70 μmol/l (indicative of vitamin A deficiency) and 0.35 μmol/l (severe deficiency) can provide useful information.
Although there is no international consensus as yet, a serum retinol concentration below 1.05 μmol/l has been proposed to reflect low vitamin A status among pregnant and lactating women.
Treatment of vitamin A deficiency is generally based on diet, and sometimes use of supplements, particularly for children with deficiency or for those with severe measles under 2 years of age, where some studies have found vitamin A to be effective in preventing serious complications.
Vitamin A has toxic effects at high serum concentrations, particularly in pregnant women, where supplementation might be teratogenic. Treatment with supplements should therefore be carefully monitored.
Vitamin A deficiency is extremely rare in people born in the UK, and there are no standard UK guidelines for the diagnosis and treatment of vitamin A deficiency. Primary care practitioners who suspect vitamin A deficiency in a migrant patient may wish to seek advice on appropriate diagnosis and treatment from their local endocrinology or paediatric team.
Prevention and control
The Department of Health recommends daily supplementary vitamin drops for all infants from 6 months to 5 years.There are specific exceptions to this, for example:
- in some circumstances vitamin supplements may need to be given earlier
- if infants are drinking 500ml of infant formula a day supplements may not be needed
See NHS Choices.
Healthy Start children’s vitamin drops contain a combination of vitamins A, C and D, and are available free of charge to children aged from 6 months to their 4th birthday in families who qualify for the Healthy Start Scheme.
NHS organisations may have local arrangements where they provide vitamins free, or at a small cost, to those not on the scheme.
- not to take supplements containing vitamin A (including fish liver oils) as they might be teratogenic
- not to eat liver or liver products, such as paté, as they may contain high levels of vitamin A
Patient.co.uk has produced a leaflet on vitamin A.
NHS Choices has more information about vitamin A.
Healthy Start has information on vouchers for healthy food for children and pregnant women.
Published: 31 July 2014