7 Glossary

At-risk groups

Although the entire UK population is at risk of having a low vitamin D status, these population groups are at higher risk:

  • People who have low or no exposure to the sun. For example, those who cover their skin for cultural reasons, who are housebound or confided indoors for long periods.

  • People who have darker skin, for example, people of African, African-Caribbean and South Asian origin.

Culturally appropriate

Culturally appropriate interventions take account of the community's cultural or religious beliefs and language and literacy skills by:

  • Using community resources to improve awareness of, and increase access to, interventions. For example, they involve community organisations and leaders early in the development stage, use media, plan events or make use of community-specific festivals.

  • Understanding the target community and the messages that resonate with them.

  • Identifying and addressing barriers to access and participation, for example, keeping costs low to ensure affordability and taking account of working patterns and education levels.

  • Developing communication strategies that are sensitive to language use and information needs. For example, involve staff who can speak the languages used by the community, and provide information in different languages and for varying levels of literacy (for example, using colour-coded visual aids and spoken rather than written information).

  • Taking account of cultural or religious values, for example, in relation to body image, separate physical activity sessions for men and women, beliefs and practices about hospitality and food, or dates, days, settings, or timings considered unsuitable for community events or interventions.

  • Providing opportunities to discuss how interventions would work in the context of people's lives.

  • Considering how closely aligned people are to their ethnic group or religion and whether they are exposed to influences from both the mainstream and their community in relation to diet and physical activity.

Dietary reference values

Dietary reference values is a collective term for reference nutrient intake, estimated average requirement and lower reference nutrient intakes. Dietary reference values reflect the amount of energy and nutrients needed by healthy people according to their age and gender. For certain nutrients, set increments reflect the increased demands associated with pregnancy and lactation.

Existing recommendations on vitamin D

The UK Health Departments, the Scientific Advisory Committee on Nutrition and NICE have all issued evidence-based guidance on vitamin D supplements for various specific population groups. (See NICE guidance on antenatal care and maternal and child nutrition.) They have also provided advice on how to distribute free Healthy Start supplements (containing vitamin D) to eligible families.

Halal

Halal refers to foods or non-food items such as cosmetics or pharmaceuticals permitted by and prepared according to Islamic law.

Healthy Start

Healthy Start is a UK-wide government scheme that provides a 'nutritional safety net' for pregnant women and families on benefits and tax credits. Women who are at least 10 weeks pregnant and families with children younger than 4 years qualify if the family receives the relevant benefits:

  • pregnant women get 1 Healthy Start voucher a week worth £3.10

  • babies younger than 1 year get 2 vouchers a week worth £6.20

  • children over 1 and under 4 years of age get 1 voucher a week worth £3.10.

Vouchers are posted every 4 weeks. They can be spent on plain cow's milk, plain fresh or frozen fruit and vegetables, or infant formula milk at retail outlets registered to accept them. These include supermarkets, grocery stores, chemists and milk rounds.

Every 8 weeks, beneficiaries get vitamin coupons to swap for Healthy Start vitamins. It is the responsibility of NHS England until October 2015 – and from then on, local areas – to provide or arrange the provision of Healthy Start vitamins. The vitamin tablets for mothers contain folic acid and vitamins C and D. Healthy start vitamin drops for children contain vitamins A, C and D.

Kosher

Kosher refers to food (or premises where food is sold, cooked or eaten), cosmetics and pharmaceuticals that comply with Jewish law.

Low vitamin D status

Low vitamin D status (sometimes called vitamin D deficiency) is defined by the Department of Health as a plasma concentration of 25 hydroxyvitamin D (the main circulating form of the vitamin) of below 25 nmol/litre (equal to 10 ng/ml).

Reference nutrient intake

Reference nutrient intake is the amount of a nutrient needed to meet the needs of 97.5% of individuals in a group. Reference nutrient intake for a given nutrient may vary by gender, age and physiological status (for example during pregnancy and lactation). The reference nutrient intake is not a minimum target that all people need to achieve, but the risk of deficiency is minimised if the average population intake exceeds it.

The current reference nutrient intakes (µg/day) for vitamin D are:

  • 10 micrograms of vitamin D per day, throughout the year, for everyone in the general population aged 4 years and older

  • 10 micrograms of vitamin D per day for pregnant and lactating women and population groups at increased risk of vitamin D deficiency.

Safe intake

Safe intakes are different to RNIs. A safe intake is used where there is insufficient evidence to set a RNI. The safe intake is the amount judged to be enough for almost everyone, but below a level that could have undesirable effects.

  • a 'safe intake' of 8.5 to 10 micrograms per day for all infants from birth to 1 year of age

  • a 'safe intake' of 10 micrograms per day for children aged 1 to 4 years.

All population groups are currently advised to take a supplement that meets 100% of the reference nutrient intake for their age group (as above). The reference nutrient intake for population groups is 10 micrograms/day (1 microgram=40 international units, so 10 micrograms=400 IU).

Specific population groups

Although the entire population of the UK are at risk of having a low vitamin D status, evidence was only considered in regard to increasing the supplement use for these specific population groups:

  • All pregnant and breastfeeding women, particularly teenagers and young women.

  • Infants and children under 4 years (breast fed, non-breast fed and mixed fed).

  • People over 65.

  • People who have low or no exposure to the sun. For example, those who cover their skin for cultural reasons, who are housebound or confined indoors for long periods.

  • People who have darker skin, for example, people of African, African–Caribbean and South Asian origin.

All population groups are currently advised to take a supplement that meets 100% of the reference nutrient intake for their age group. The reference nutrient intake levels are noted above.

All infants and young children aged 6 months to 3 years are advised to take a daily supplement containing vitamin D in the form of vitamin drops. But infants who are fed infant formula will not need them until they have less than 500 ml of infant formula a day, because these products are fortified with vitamin D. Breastfed infants may need drops containing vitamin D from 1 month of age if their mother has not taken vitamin D supplements throughout pregnancy. ('Vitamin D – advice for supplements for at risk groups – letter from the UK Chief Medical Officers' Department of Health).

Vegan

People who follow a vegan diet consume only plant products. They avoid all food, drink and non-food items, such as pharmaceuticals that contain any animal products.

Vitamin D

Vitamin D is a fat soluble pro-hormone. It is obtained through the action of sunlight on skin and from dietary sources. The action of sunlight (ultraviolet radiation of wavelength 290–310 nm) on skin converts 7‑dehydrocholesterol to previtamin D3, which is then metabolised to vitamin D3.

Dietary vitamin D exists as either ergocalciferol (vitamin D2) or cholecalciferol (vitamin D3).

The liver 25-hydroxylase enzymes convert vitamin D2 and D3 (from diet or from the action of sunlight on skin) to the main circulating form of the vitamin, 25 hydroxyvitamin D – also known as 25(OH)D. This is then converted by the kidney and other tissues to the active form of the vitamin 1,25-dihydroxyvitamin D.

  • National Institute for Health and Care Excellence (NICE)