In this guidance, the term 'diet' refers to the habitual eating patterns of individuals and groups of people who are not slimming or eating to manage or treat a medical condition.

Dietary reference values (DRVs)

DRVs are a collective term for: reference nutrient intake, estimated average requirement and lower reference nutrient intakes. These terms were introduced into the UK in 1991 to replace the term 'recommended daily amount'. DRVs reflect the amount of energy and nutrients needed by different groups of healthy people according to their age and gender. For certain nutrients, set increments reflect the increased demands associated with pregnancy and lactation.

Exclusive breastfeeding

Exclusive breastfeeding means an infant receives breast milk only and no other liquids or solids. The only exceptions are drops or syrups containing vitamins, mineral supplements or medicines.

Follow‑on formula

Under UK law, follow‑on formula may provide the liquid component of a progressively varied diet for healthy infants aged over 6 months.

Food allergy

A food allergy is an adverse reaction. It occurs when the immune system reacts to a particular food. Common allergic reactions include itchy skin or a rash and wheezing or shortness of breath. Severe allergic reactions can be life‑threatening. This should not be confused with food intolerance.

Healthy eating

There is no standard definition. However, it is widely accepted that 'healthy eating' means following a diet which is low in fat (particularly saturated fat), sugar and salt, and high in fruit, vegetables and fibre‑rich, starchy foods. More details are available from the Food Standards Agency.

Hydrolysed infant formula

Infant formula (see below) containing protein which has been broken down (hydrolysed) either partially or more extensively. Hydrolysed infant formula is more expensive than other infant formula and is usually available on prescription.

Infant formula

Under UK law, infant formula is the term used to describe a food intended to satisfy, by itself, the nutritional needs of infants during the first months of life. The DH advises that infant formula may be used on its own for the first 6 months.

Low birth weight (LBW)

Low birth weight is defined by the World Health Organization as less than 2500 g (Kramer 1987).

Mixed feeding

Mixed feeding is the practice of feeding an infant both breast milk and infant formula.

Neural tube defects (NTDs)

The neural tube in the fetus develops into the brain and spinal cord. Neural tube defects occur when the brain, skull and/or the spinal cord and its protective spinal column do not develop properly within the first 4 weeks after conception. The most common NTDs are anencephaly (which results in stillbirth or death soon after delivery) and spina bifida (which may lead to a range of physical disabilities including partial or total paralysis).

Nutritional status

Nutritional status describes an individual's nutritional wellbeing. It is a more comprehensive measure than dietary intake alone as it takes account of body shape and size together with measures of body function.


Postpartum generally refers to the first 6 weeks after the birth of a baby. However, in the review of 'postpartum' women for this guidance, it refers to the first year after the baby's birth.

Reference nutrient intake (RNI)

RNI is the amount of a nutrient required to meet the needs of around 97% of individuals within a group. RNI for a given nutrient may vary by gender, age and physiological status (examples of the latter include pregnancy and lactation). The RNI is not a minimum target that all individuals need to achieve but the risk of deficiency is minimised if the average population intake exceeds it.

Supplementary feeding

Supplementary feeding means infants who mainly receive breast milk, receive some additional infant formula.


Weaning or 'complementary feeding' is the transition from an exclusively milk‑based diet to a diet based on solid foods.