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Vegetable oil in a quantity of about 1% of the chicory

load is added to bind the dust and to prevent sticking

of chicory to the roaster wall and baffles. The com-

bustion gases are first directed around the drum and

are then drawn through the drum. The moisture in the

chicory is driven off and is removed by the combus-

tion gases. In the later stages of roasting, the heat

supply is reduced by steps and the heating gases are

only drawn outside around the drum. The actual

roasting takes place at temperatures of 170–180



After a roasting time of 60–80 min the chicory

reaches the required color and is discharged into the

cooling screen. The total roast loss is in the range of

15–25%.

0008 Roast and ground chicory is usually blended with

coffee or cereals and marketed as coffee mixture or

coffee substitute. (See Coffee: Roast and Ground.)

Otherwise, it may be extracted and dried.

Extraction and Spray Drying

0009 Roasted chicory is more frequently extracted in

blends with roasted coffee or roasted cereals than

alone by itself. This extraction with coffee or cereals

is done in percolation batteries which consist of about

six columns connected in series. Hot water is pumped

into the column which contains the most spent roasted

material, flows in a counterclockwise fashion through

the plant and finally enters the column with fresh

roasted material. The concentration of the draw-off

extract varies from 15 to 30% and depends on, among

other factors, the composition of the roast blend.

Each column with an exhausted blend is replaced by

one with a new roast blend. The feed water tempera-

tures may be up to 180



C with blends of coffee and

chicory, or up to 140



C with blends of cereals and

chicory. Heat exchangers placed between the columns

lower the extract temperature in stages down to 90



in the column with the fresh roast blend. The extrac-

tion yield and the draw-off concentration increase

with higher temperature profiles. Since chicory con-

tains a high proportion of soluble carbohydrate, it

can be extracted efficiently at temperatures below

100



0010 The extraction of roasted chicory by itself is per-

formed in twin-screw conveyors or hydraulic piston

presses. Pure chicory extracts are, for the most part,

subsequently mixed with coffee or cereal extracts.

The liquid extracts are sometimes concentrated

before spray drying or mixed with glucose syrup in

order to improve the drying properties of the extract.

(See Coffee: Instant.)

0011 The spray drying of the liquid extracts with soluble

solid contents of 30–45% is conducted in tall towers

in which the extract is pumped under high pressure

through nozzles and is dispersed into small droplets.

In the upper part of the tower the water in the drop-

lets evaporates in a flow of hot air; in the lower part

the exhaust air is drawn off and the separated powder

is collected in bins. The instant powders, which have

a moisture content of about 3%, are filled into water

vapor-tight containers such as jars with sealable lids.

Composition and Varieties

0012The composition of two chicory varieties based on

dry matter is given in Table 1. The water content

of fresh chicory roots is in the range 70–80% and

is influenced by the variety, the soil, and weather

conditions. The solid matter of finely ground chicory

roots is extractable in boiling water to an extent of

80%. Chicory is characteristic in that the main con-

stituent of the roots is the polysaccharide inulin. This

reserve carbohydrate with a molecular weight of ap-

proximately 6000 comprises up to 65% of the dry

matter of the root. About 35 fructose molecules are

linearly linked together with one glucose molecule at

the end. The polymer chain of inulin is completed by

a sucrose molecule and, therefore, it has no reducing

power. In addition, chicory roots contain further

carbohydrates, including usually contents of about

5% sucrose and about 15% fiber substance. During

extraction, the fiber remains insoluble in the residue.

Nitrogenous compounds amount to about 6% and

comprise protein and free amino acids. The content of

organic acids is about 3%, of which malic acid and

citric acid are about 30% each. Mineral substances

are present at about 5% in the root, the most im-

portant components being potassium, calcium,

phosphate, and sulfate. Furthermore, the roots

contain lactucin and lactucopicrin in a total amount

of about 0.4%. These sesquiterpene lactones are

tbl0001Table 1 Composition (grams per 100 g) of chicory varieties

Variet y superior in

Root quality Field yield

Dry matter

26.9 21.7

Extractable matter

82.2 80.0

Composition

Inulin 64.1 57.8

Sucrose 5.3 7.8

Protein 4.5 5.5

Amino acids 1.1 1.5

Organic acids 2.6 3.2

Fiber 13.6 16.1

Minerals 4.0 5.0

Others 4.8 3.1

Based on root weight.

Based on dry weight.

1146 CHICORY BEVERAGES

responsible for the bitter taste of fresh and dried

chicory. Both lactones are completely decomposed

during roasting. (See Acids: Natural Acids and Acid-

ulants; Amino Acids: Properties and Occurrence;

Carbohydrates: Classification and Properties; Min-

erals – Dietary Importance; Protein: Chemistry.)

0013 It is known from screening tests of chicory varieties

that a negative correlation exists between the root

quality and the field yield. Breeding of chicory aims

at combining both attributes. A variety with a super-

ior root quality has a higher content of inulin, and dry

and soluble matter, and, conversely, a variety with

a superior field yield has a high root weight, and a

high content of protein and minerals. For these two

opposing chicory varieties, yields of fresh roots and

calculated yields of dry matter and soluble solids are

given in Table 2.

Changes in Composition During

Processing

0014 Higher temperatures in the root heaps during longer

storage periods induce the start of hydrolysis of the

polysaccharide by the enzyme inulinase present in the

roots. The generated sugars favor loss of material as a

result of respiration of the roots and also by decay

through microbial activity. Fresh roots should, there-

fore, not be stored for long periods at high tempera-

tures in order to minimize inulin hydrolysis and other

causes of losses. The ideal storage conditions would

be temperatures of about 5



C and air humidities of

about 95%, which normally cannot be achieved in

practice.

0015 Very high temperature profiles during drying cause

puffing of the wet chicory pieces. Hollow spaces

remain inside after drying which reduce the firmness

of the cubes or slices and increase the tendency to

break more easily during transport. Chicory pieces

with larger dimensions usually leave the drum drier

still with moist centers. During storage, enzymatic

hydrolysis of the inulin proceeds at a rate dependent

on the moisture content, and the sugar content

increases. Dried chicory should normally show a

bright color, a low content of reducing sugar, and a

high content of extractable solids and inulin. Darker

outer colors and burnt edges of dried chicory

enhance water uptake during storage and make it

more difficult to obtain a homogeneous roast. Higher

sugar contents of dried chicory are sometimes

accepted in view of the taste of the product, but they

impair further processing due to the higher hygrosco-

picity.

0016Roasting of chicory results in the formation of

specific color, flavor, and aroma compounds which

are characteristic of the product. The constituents of

chicory, such as inulin, sucrose, protein and free

amino acids, partially or totally undergo various

changes. Most alterations in the chemical compos-

ition are connected with two browning reactions –

the Maillard reaction and the pyrolysis of the inulin.

The Maillard reaction takes place between the redu-

cing sugars and the amino groups of free amino acids

and proteins, giving the melanoidins (brown poly-

meric materials) and volatile aldehydes. These give

chicory its typical flavor. The pyrolytic degradation

of inulin yields high-molecular-weight caramel com-

pounds and low-molecular-weight carbonyl com-

pounds, such as aldehydes, ketones, and organic

acids. These compounds likewise contribute to the

color and the taste of roasted chicory. (See Browning:

Nonenzymatic.)

0017The analytical values in Table 3 illustrate the

changes in the carbohydrate composition and the

free acidity during chicory roasting. The decompos-

ition of inulin and the formation of free acids steadily

proceed with increasingly darker roasting. The con-

tents of reducing sugars, of fructose, and of glucose

first increase during roasting, reach a maximum, and

decrease again. The content of reducing sugars in, for

example, cubes or slices reaches a maximum value of

15%. Insoluble matter is formed by the strongly exo-

thermic pyrolysis of inulin and lowers the amount

of extractable material, especially of dark roasted

chicory. Light and medium roasted chicory are

tbl0002 Table 2 Yields (tonnes per hectare) of chicory varieties

Variet y superior in

Root quality Field yield

Fresh roots 40.7 46.9

Dry matter

10.9 10.2

Soluble acids

9.0 8.1

Calculated with the values of Table 1.

tbl0003Table 3 Characteristic values (grams per 100 g of dried matter)

of dried and roasted chicory

Roasted

Dried Light Medium Dark

L-Color value of powder 77.0 46.4 40.0 32.5

Extractable matter 83.1 82.8 82.2 78.3

pH value

5.7 4.7 4.6 4.4

Acid degree

a,b

12 27 31 40

Reducing sugars 1.9 8.4 14.1 12.1

Free fructose 0.5 2.4 4.6 3.4

Free glucose 0.1 1.0 2.2 1.9

Inulin and sucrose 67.1 52.6 39.1 24.8

Measured in a 1% extract solution.

Defined as millimoles of sodium hydroxide per 100 g of soluble solids.

CHICORY BEVERAGES 1147

extractable in boiling water to about 80%, whereas

the extractable content of dark roasted chicory is

lower. In addition, the heat generated inside the chic-

ory pieces by the pyrolytic reaction accelerates the

roasting and leads to charring of the cores.

0018 During extraction, free acids already present in

roasted chicory hydrolyze inulin to monosaccharides.

Fructose, itself thermally unstable, is subjected to

further decomposition, the extent of which depends

strongly on the extraction conditions. Shorter extrac-

tion times and lower water temperatures are con-

sidered favorable to minimize the amount of free

fructose and free acids in the chicory extracts.

0019 The analytical values stated in Table 4 show that

temperatures below 100



C should be applied for the

extraction of chicory.

0020 Fructose has a steeper sorption isotherm than inu-

lin and is very hygroscopic. As a result, light roasted

chicory with more inulin and less fructose is prefer-

ably used for the production of instant powders.

Chicory extracts have a higher hygroscopicity and

an increased stickiness, in contrast to coffee or cereal

extracts. This means that, compared to pure coffee,

the output capacity of the spray drier is reduced by

extracts produced from roasted coffee–chicory or

cereal–chicory blends and, in particular, by pure chic-

ory extracts. (See Fructose.) In addition, spray drying

of extracts containing chicory-soluble solids is more

difficult and requires certain precautions.

Taste and Physiological Effects

0021 Infusions of light roasted chicory have a sweetish and

mild flavor. In combination with coffee or cereals, the

chicory imparts to the beverage a smooth and round

taste. With darker roasting of the chicory, the sweet

taste diminishes and the strength, astringency, acidity,

and bitterness of the brew increase.

0022 Information concerning the physiological effects

of roasted chicory is exceedingly scarce. A lot of

practical advice compiled over the years, concerning

natural medicine, is found in old literature. According

to this knowledge, infusions of roasted chicory are

beneficial and contribute to the well-being of the

body. Chicory brews are supposed to be mild diuretics

and are said to have sedative effects. It has been known

for a long time that chicory promotes digestion by

stimulating the secretion of the gastrointestinal

glands and especially by increasing bile production.

Some investigators claim that the digestion of milk is

facilitated by the addition of chicory because the finer

milk particles formed in the stomach are more easily

digested. Modern scientific studies confirm these con-

clusions. Tests performed on animals and humans

substantiate the fact that chicory is perfectly safe

and has no adverse effects. Some physiological effects

were thought to be related to the sesquiterpene lac-

tones contained in fresh or dried chicory. These lac-

tones are decomposed during roasting and therefore

are absent from roasted chicory.

0023Soluble chicory powders can contain up to 60%

inulin or oligomer compounds derived from it. Inulin

and fructose oligomers are soluble dietary fibers. This

means that they are not hydrolyzed in the small intes-

tine. In the intestine, however, they are fermented by

the microflora, so a considerable amount of bacterial

mass is produced and bifidobacteria development is

promoted. These fibers are well tolerated. As inulin is

not hydrolyzed in the stomach and the small intestine,

it has no influence on the blood glucose and can be

used in diabetic diets. (See Coffee: Physiological

Effects.)

Use as an Adulterant and Analysis

0024Roast and ground coffees or instant coffee powders

may be adulterated by mixing chicory with coffee

after roasting, before extraction or even after drying.

Microscopic, physical, and chemical methods are

applied to detect and to analyze the adulteration of

roasted or soluble coffee with chicory. Cell structures

from chicory can be identified by the examination of

suspicious samples of roasted coffee under the micro-

scope. The extractability of roasted coffee and

roasted chicory differ enormously: finely ground

coffee is extractable in boiling water to about 30%,

chicory to about 80%. From the increase in coffee

extractability, the portion of chicory in roast and

ground coffee can be estimated. Several methods

depend on the analysis of specific constituents present

in either coffee or chicory, but not both. The deter-

mination of the content of total fructose appears most

suitable, since the content of fructose in chicory is

relatively high compared to the content of caffeine

and chlorogenic acids in coffee. Although all these

methods detect the adulteration of coffee, it is

tbl0004 Table 4 Increase of free acids and free sugars during storage

of a liquid chicory extract (23% dry matter, 61% inulin and

sucrose) for 1 h at different temperatures

Treatedat

Original 60



C80



C100



C120



C140



pH value of extract 4.7 4.7 4.6 4.5 4.1 3.6

Acid degree

21 22 23 26 34 68

Free fructose

2.7 3.0 3.7 8.2 54.3 44.7

Free glucose

1.2 1.2 1.4 1.7 5.3 8.8

Defined as millimoles of sodium hydroxide per 100 g of soluble solids.

Grams per 100 g of dry matter.

1148 CHICORY BEVERAGES

difficult to specify the blend quantitatively. (See

Adulteration of Foods: History and Occurrence.)

See also: Acids: Natural Acids and Acidulants;

Adulteration of Foods: History and Occurrence; Amino

Acids: Properties and Occurrence; Browning:

Nonenzymatic; Carbohydrates: Classification and

Properties; Coffee: Roast and Ground; Instant;

Physiological Effects; Fructose; Minerals – Dietary

Importance; Protein: Chemistry

Further Reading

Beitter H and Schro

der C-H (1970) Handbuch der Lebens-

mittel-Chemie, vol. VI, pp. 96–138. Berlin: Springer

Verlag.

Clarke RJ and Macrae R (1987) Related Beverages, Coffee,

vol. 5. London: Elsevier.

Maier HG (1981) Kaffee, pp. 146–194. Berlin: Parey.

Niness KR (1999) Inulin and oligofructose: what are they?

Journal of Nutrition 129: 1402S–1406S.

CHILDREN

Contents

Nutritional Requirements

Nutritional Problems

Nutritional Requirements

B Caballero, Johns Hopkins University, Baltimore,

MD, USA

Nutritional Requirements

Assessment of Nutritional Status

0001 Normal growth is one of the most important indica-

tors of nutritional status. Monitoring of weight and

height (or recumbent length when appropriate)

should be performed at regular intervals, with fre-

quency depending on the age of the child. Infants

are usually measured monthly during the first 6

months of life, and at bimonthly intervals during the

remainder of the first year.

0002 However, it is difficult to determine the adequacy

of children’s diet only by physical examination. Many

clinical signs of nutrient deficiencies only appear in

the advanced stages. Thus, interrogation on food

habits and intake, and even use of dietary records

may be necessary when the possibility of inadequate

intake is considered.

Nutrition from 1 to 5 Years of Age

0003 The first 5 years of life are among the periods of more

rapid growth. Major changes also occur in the rela-

tive size of the body regions and in the proportions of

water, fat, and lean mass tissues. Over these years,

nutrition must accommodate a changing pattern of

energy, protein, and micronutrient needs. (See Infant

Foods: Weaning Foods; Infants: Weaning.)

0004The growth pattern after the first year of life shows

periods of both rapid and slow gain in stature and

weight. Children tend to grow 12 cm during the

second year, 9 cm in the third, and 7 cm or less there-

after. (See Growth and Development.)

0005After the first year, healthy children should be able to

eat virtually the same as adult members of the family.

Indeed, it is at this stage that family dietary practices

have the most significant impact on the child’s prefer-

ences and food intake patterns. It is thus important for

parents to be aware of their role in educating and

forging sound dietary habits in their children.

0006The feeding behavior of children at this age is much

more variable than previously. Children have a much

wider repertoire of eating behaviors, and should be

allowed, within reason, to practice them. As a rule, a

healthy child should be allowed to eat as much or as

little as he or she wishes. Forced feeding or threats

around food do not lead to good nutrition, but rather

to sometimes long-term confrontation, to the detri-

ment of actual food intake. Furthermore, there is

evidence that healthy children have a quite accurate

mechanism of maintaining energy balance by com-

pensating for deficient or excessive food intake over

periods of days or even weeks. (See Infants: Feeding

Problems.)

Nutrition over 5 Years of Age

0007The growth pattern between 5 and 10 years of age

is usually more stable than during earlier years,

CHILDREN/Nutritional Requirements 1149

averaging about 5 cm per year. Weight gain is around

2 kg per year at 5–6 years of age, and increases rapidly

as puberty approaches, reaching as much as 4 kg

per year by age 10. Physical activity also increases

markedly during school years, as children become

more involved in sports and outdoor activities in

general.

Recommended Nutrient Intake

0008 Gender differences in nutrient requirements are usu-

ally not substantial until preadolescence and menar-

che. At that time, genders begin to diverge in terms of

body fat and skeletal muscle accumulation, which are

to be reflected in nutrient requirements.

Protein and Energy Requirements

0009 Dietary energy needs of infants are usually estimated

from the ad libitum energy intake of healthy children

growing at a normal rate. In older children estimates

can be derived, as for adults, from equations based

on resting energy expenditure and body size. Since

recommended energy intakes should match energy

expenditure (with normal growth and adequate phys-

ical activity), the best approach to estimate energy

needs would be from measurements of daily energy

expenditure. Until recently, the number of studies

measuring daily energy expenditure in free-living in-

dividuals has been small, due mainly to the cost and

complexity of the doubly labeled water technique.

But the increasing number of studies with that tech-

nique is now approaching a critical number that will

allow ongoing revisions of recommended energy

intakes to be based on direct energy expenditure

measurements. Until these revisions (by the US Insti-

tute of Medicine, the World Health Organization,

and others) are released, existing recommendations

are presented in Table 1.

0010For protein, estimates of requirements continue to

be based primarily on patterns of dietary protein

intakes of normal infants and children, with the con-

sideration of nitrogen balance data when available.

Requirements for indispensable amino acids have

also considered the information obtained by stable

isotope tracer studies (Table 2). (See Protein: Require-

ments.)

Vitamins and Minerals

0011Recommendations for most vitamins and minerals

were recently revised by the US Food and Nutrition

Board (See Dietary Reference Values), and are pre-

sented in Table 3. For nutrients and age groups for

which there are no sufficient data to determine the

traditional recommended dietary allowance (RDA),

the committee introduced the adequate intake (AI).

This variable indicates observed intakes in healthy

groups, and thus is assumed to be adequate. It can

be used as an RDA, but it is obviously less accurate.

Food Additives

0012Over the years, several investigators have proposed

that certain food additives could have a major behav-

ioral impact on young children. But in spite of many

years of research and controversy, there is no compel-

ling evidence supporting those claims. Nevertheless,

there are documented intolerances to some additives

such as sodium glutamate and sulfites in adults,

which can also occur in children.

Dental Development

0013Dental development is another important milestone

during school age. Dental caries can appear early, and

some surveys found that over 50% of children aged

3–4 years of age had dental caries. Major nutrients

tbl0001 Table 1 Recommended energy and protein intake in children

aged 1–10 years

Age (years) Energy

(kcalkg

1

day

1

)

Protein

(g kg

1

day

1

)

1–2 105 1.20

2–3 100 1.15

3–5 95 1.10

5–7 1.0

Boys 90

Girls 85

7–10 1.0

Boys 78

Girls 67

Data from World Health Organization (1985) Energy and Protein

Requirements. FAO/WHO/UNU Expert Consultation. WHO Technical Report

Series 724. Geneva: WHO.

tbl0002Table 2 Essential amino acid requirements during childhood

Amino acid

(mgg

1

crude protein)

Preschoolchild

(2^5 years)

School child

(5^19 years)

Adult

Histidine 19

Isoleucine 28 28 13

Leucine 66 44 19

Lysine 58 44 16

Methionine and cystine 25 22 17

Phenylalanine and tyrosine 63 22 19

Threonine 34 28 9

Tryptophan 11 9

Valine 35 25 13

Data from World Health Organization (1985) Energy and Protein

Requirements. FAO/WHO/UNU Expert Consultation. WHO Technical Report

Series 724. Geneva: WHO.

Values interpolated from requirement versus age curves.

1150 CHILDREN/Nutritional Requirements

related to dental development are fluoride, and vita-

min D, calcium and phosphorus (enamel formation),

vitamin A and C, zinc, and folate (gum integrity).

Adequate intake of these nutrients is usually not a

problem in developed societies. Of more practical

importance are, perhaps, a number of dietary habits

which may favor dental caries: excessive use of sugar

and other fermentable carbohydrates, the nursing

bottle syndrome (the baby is allowed to fall asleep

while sucking a sweetened beverage, or even human

milk), and poor dental hygiene. (See Dental Disease:

Etiology of Dental Caries.)

A Prudent Diet for Children

0014 There is growing awareness of the importance of diet

in the development of chronic diseases, e.g., obesity

and coronary heart disease. A number of changes in

the current dietary practices of developed societies

have been proposed, although the long-term impact

of these changes is still unclear. There is also the

question of how early in life a ‘prudent’ diet should

be adopted. Special issues of nutrition in childhood,

such as nutrient density, protein digestibility, and

micronutrient requirements, need to be recognized.

For example, there must be awareness of the potential

negative impact that high-fiber or all-vegetable diets

may have on protein digestibility, mineral bioavail-

ability, and energy density. (See Dietary Fiber: Effects

of Fiber on Absorption.)

See also: Dental Disease: Etiology of Dental Caries;

Dietary Fiber: Effects of Fiber on Absorption; Dietary

Reference Values; Growth and Development; Infant

Foods: Weaning Foods; Infants: Weaning; Feeding

Problems; Protein: Requirements

Further Reading

Caballero B (1985) Food additives in the pediatric diet.

Clinical Nutrition 4: 200–206.

Committee on Nutrition, American Academy of Pediatrics

(1998) Pediatric Nutrition Handbook. Elk Grove

Village, IL: American Academy of Pediatrics.

US Food and Nutrition Board, Institute of Medicine (1997–

2001) Dietary Reference Intakes. Calcium and Related

Nutrients (1997); Thiamin, B-complex Vitamins (1999);

Vitamins C, E, Selenium (2000), Vitamins A, E, K, and

others (2001). Washington, DC: National Academy

Press.

World Health Organization (1985) Energy and Protein

Requirements. FAO/WHO/UNU Expert Consultation.

WHO Technical Report Series 724. Geneva: WHO.

Nutritional Problems

D Bentley, Imperial College of Science Technology

and Medicine, London, UK

Rickets

0001Deficiency of vitamin D in the growing child leads to

rickets (Figure 1), a metabolic disorder common in

English and American polluted cities during the

Industrial Revolution. The term indicates a failure in

mineralization of growing bone or osteoid tissue. The

typical clinical picture was well described in the

seventeenth century and the cause was secondary to

poor nutrition, arising from both financial and edu-

cational poverty as well as the result of a hazy,

smoggy atmosphere with little exposure to sunshine

or ultraviolet (UV) radiation. Adequate sunshine

tbl0003 Table 3 Recommended daily intakes of vitamins and minerals

for children aged 1–10 years

Age of child (years)

1^3 4^8

Vitamin A (mg day

1

) 300 400

Vitamin D (mg day

 1

)

a,b

5* 5*

Vitamin K (mg day

1

)3055

Vitamin C (mg day

1

) 15 25

Vitamin E

(mg day

1

) 67

Thiamin (mg day

1

) 0.5 0.6

Riboflavin (mg day

1

) 0.5 0.6

Niacin (mg day

1

)

Vitamin B

(mg day

1

) 0.5 0.6

Folate (mg day

1

)

150 200

Vitamin B

(mg day

1

) 0.9 1.2

Pantothenic acid (mg day

1

)2* 3*

Iron (mg day

1

) 710

Zinc (mg day

1

) 35

Iodine (mg day

1

) 90 90

Calcium (mg day

1

) 500* 800*

Phosphorus (mg day

1

) 460 500

Magnesium (mg day

1

) 80 130

Selenium (mg day

1

) 20 30

This table presents recommended dietary allowances (RDAs) in bold type

and adequate intakes (AIs) in ordinary type followed by an asterisk (*).

RDAs and AIs may both be used as goals for individual intake. RDAs are

set to meet the needs of almost all (97–98%) individuals in a group.

As cholecalciferol. 1 mg cholecalciferol ¼40 IU vitamin D.

In the absence of adequate exposure to sunlight.

As niacin equivalents (NE). 1 mg of niacin ¼60 mg of tryptophan; 0–6

months.

As dietary folate equivalents (DFE). 1 DFE ¼1 mg food folate ¼0.6 mgof

folic acid from fortified food or as a supplement consumed with

food ¼0.5 mg of a supplement taken on an empty stomach.

As a-tocopherol. a-Tocopherol includes RRR-a-tocopherol, the only form

of a-tocopherol that occurs naturally in foods, and the 2R-stereoisomeric

forms of a-tocopherol (RRR-, RSR-, RRS-, and RSS-a-tocopherol) that

occur in fortified foods and supplements. It does not include 2S-

stereoisomeric forms of a-tocopherol (SRR-, SSR-, SRS-, and SSS-a-

tocopherol), also found in fortified foods and supplements.

CHILDREN/Nutritional Problems 1151

is not the entire explanation because rickets was

common in the 1940s in southern California as it is

today in India. Furthermore, from October to March

no UV light reaches the earth’s surface in the UK and

consequently vitamin D is not formed in the skin

during that period. The incidence of rickets declined

after the 1927 discovery that UV irradiation of ergos-

terol, a vitamin D plant derivative, increased its anti-

rachitic effect.

0002 Skin photochemical synthesis is the major source of

vitamin D, and tanning prevents further formation.

Black infants have lower circulating vitamin D levels

than white children. This is because white skin allows

vitamin D-inducing wavelengths to pass through but

black skin filters UV radiation under wavelengths of

436 nm. With the development of vitamin D-fortified

milks and milk products, rickets has decreased in

incidence. However, in some countries, cows’ milk is

not routinely fortified. Human milk contains almost

20 times more of this vitamin than unmodified whole

cows’ milk, yet in the USA a revival in breast-feeding

has been linked to an increase in cases of nutritional

rickets.

0003Rickets was described in Asian immigrants in

Glasgow, Scotland in 1956. An estimate of the 1977

incidence of clinical overt rickets among UK Asians

aged 0–16 years was 4 cases per 1000 in London and

10 per 1000 in the Midlands and the north of Eng-

land. Rickets seemed to increase in the UK from 1960

to 1973, then decreased but has returned to the West

Midlands in the UK (2002). Pregnant Asian women

with osteomalacia risk having infants with neonatal

convulsions as a result of hypocalcemia. Typically

rickets is seen in breast-fed premature and growth-

retarded infants and is especially prevalent in those

born to Asian mothers in the UK. Phytic acid is a

modifier of calcium absorption and one source is

unrefined cereals such as chapattis (unleavened

breads). This has been implicated in the causation of

Asian rickets. High-phytate diets will increase vita-

min D requirements. Infants on macrobiotic diets

(e.g., unpolished rice, pulses – rich in fiber) and who

do not receive vitamin D supplements are at risk.

Rickets has also been described in the fetus. Adoles-

cent Asian rickets, characteristically in children 8–14

years old, may present with gross genu valgum

Bone

Kidney

Liver

Skin

Ultraviolet

light

Degraded

vitamin D

compounds

Site of first hydroxylation

Enzyme is 25-hydroxylase

(Vitamin D

cholecalciferol)

(7-Dehydrocholesterol in skin)

25 (OH)D

Gut

Dietary calcium

and phosphorus

transferred in

presence of

1, 25 (OH)

Via plasma

Site of reabsorption

Site of second hydroxylation

to 24, 25 (OH)

(inactive) and

1α, 25 (OH)

(metabolically

active form of vitamin D)

Sun

fig0001 Figure 1 Vitamin D is derived from the diet and from the effect of ultraviolet light on the skin. It is hydroxylated in the liver (25(OH)D

)

and undergoes a second hydroxylation in the kidney to the biologically active form, 1,25-dihydroxycholecalciferol (1a25(OH)

), which

acts on the gut and bone to increase gut absorption. 24,25(OH)

is 24,25-dihydroxycholecalciferol. Courtesy of Professor P. Byrne.

1152 CHILDREN/Nutritional Problems

(knock knee) and aching joints. Other clinical

features include leg bowing, poor linear growth,

delayed dental eruption, and impaired closure of the

skull’s fontanelle. Other skeletal deformities may

develop.

Causes

0004 The causes of rickets in children are as follows:

0005 Inadequate exposure to sunlight

0006 Inadequate vitamin D intake

0007 Malabsorption of vitamin D, e.g., celiac disease,

short-bowel syndrome, bacterial overgrowth in

the bowel, deficiency of bile salts, cystic fibrosis

0008 Increased enzyme activity; anticonvulsants (phe-

nobarbital and/or phenytoin) will increase meta-

bolic degradation of 25(OH)D

by stimulating

hepatic microsomal enzymes

0009 Decreased enzyme activity: vitamin D-dependent

rickets (pseudovitamin D deficiency; deficiency

of the renal enzyme, 25-hydroxyvitamin D

a-hydroxylase)

0010 Acquired deficiency of 1a-hydroxylase, e.g.,

chronic renal failure

0011 Failure of 25-hydroxylation, e.g., chronic liver

failure

0012 Fanconi’s syndrome – phosphaturia: the principal

component of the disorder results in hypophos-

phatemic rickets

Diagnosis

0013 Early manifestation of rickets includes:

0014 Craniotabes (skull feels like a ping pong ball)

0015 Frontal bossing and thickening of the skull (hot

cross bun appearance)

0016 Rachitic rosary (enlarged costochondral junctions

of the ribs)

0017 Widening of the epiphyses at the wrists

In active rickets, there is cupping and fraying of the

distal ends of the forearm and parts of the skull are

demineralized. There is an increased distance

between distal ends of the forearm bones and the

metacarpals.

Biochemical Findings

0018 The following biochemical findings are characteristic

of rickets:

0019 Increased plasma alkaline phosphatase (isoen-

zyme originating in bone)

0020 Phosphate reduced or normal

0021 Calcium reduced or normal

0022 Serum parathyroid hormone normal or increased

Treatment

0023Adequate amounts of dietary calcium and phosphate

should be insured with vitamin D therapy.

Obesity

0024It is somewhat ironic that the commonest nutritional

problem in affluent countries is obesity, in sharp con-

trast to the undernutrition in less privileged societies.

Overweight and obesity are important public health

problems and are increasing at an alarming rate.

Obesity is the presence of excessive body fat and

the visual identification of severe obesity is readily

made. Weight in itself is an unsatisfactory way to

assess fatness and particularly so in younger children

where there is a poor relationship between weight and

fat. (See Obesity: Etiology and Diagnosis.)

0025In adults one indicator of obesity is Quetelet’s

index (QI), which determines the body mass, or

(weight)/(height)

, but in children it is less useful

because of a variation with age. The weakness of the

QI is that it fails to take account of the distribution of

body fat which influences health risks. However, this

parameter can be related to a theoretical child with

height and weight upon the 50th centile, and the

measure then gives a percentage value; 90% indicates

underweight, 90–110% normal weight, 110–120%

overweight, and > 120% obese.

0026Clinical examination needs to include an assess-

ment of pubertal development and anthropometry,

which must be carefully evaluated. In addition, the

observer ought to be aware of particular disorders

associated with obesity, e.g., Down’s syndrome,

Prader–Willi syndrome, Klinefelter’s syndrome and

the Laurence–Moon–Biedl syndrome, as well as

some endocrine diseases (hypothyroidism, Cushing’s

syndrome).

0027Body fatness can be assessed with a skinfold

calliper at a number of sites, a tape measure, a stadi-

ometer, and weighing apparatus. Bioelectrical imped-

ance (BIA) and dual X-ray absorptiometry (DEXA)

are the most widely used of the more elaborate

options. Other techniques include underwater weigh-

ing and densitometry, near-infrared spectroscopy

(NIR), and measurement of naturally occurring iso-

topes. Centile charts for triceps skinfold thickness, in

boys and girls, are available. Values exceeding the

97th centile are indicative of obesity. (See Obesity:

Fat Distribution.)

Prevalence

0028As many as one-third of the population of some in-

dustrialized nations are obese; in North America

obesity affects 25% of children and adults, yet in

CHILDREN/Nutritional Problems 1153

other communities, such as Finland, it is seen in

only 3%.

Etiology

0029 It is uncommon for a child to be obese because of an

underlying pathological condition (e.g., Prader–Willi

syndrome or the Laurence–Moon–Biedl syndrome).

Obesity develops only if there is a positive energy

balance; this is contrary to some views – there are

opinions which imply that not all obese children eat

excessively. Overweight children are less active than

their leaner counterparts and this pattern of reduced

physical activity is of importance.

0030 Many factors are involved in the etiology of fat-

ness, including behavioral problems, feeding patterns

within the family, nature of newborn feeding, attitude

of parents and siblings to obesity, and physical activ-

ity. Fetal and neonatal growth factors are also associ-

ated with the pathogenesis of obesity.

0031 Recent discoveries regarding obesity are related to

the hormone leptin and the identification of certain

genes in animal models. Leptin precursors and the

hormone itself are produced by placenta, fetal tissues,

gastric mucosa, and hepatic stellate cells, which can

participate in many physiological functions.

Management

0032 Specialized obesity clinics have many advantages,

particularly if located at school. Serial measures of

height, weight, and skinfold thickness need to be

recorded. Whatever the cause of obesity, management

must include a reduction in intake of energy. Regular

exercise also aids weight loss. Behavioral therapy has

been shown to have a role. Anorectic drugs are only a

transient aid because the original obesity will re-

appear after a time. (See Obesity: Treatment.)

0033 A multidisciplinary support group made up of

parents, peers, nutritionist, pediatrician, and a ther-

apist or clinical psychologist has much to offer. Food

fads or crash diets are potentially dangerous and must

be avoided in childhood, if not in adulthood too. The

aim of treatment is to correct faulty eating habits and

not to induce ketosis.

0034 Parents of children under 5 need advice to avoid

offering a high intake of fat and sugar. Incidences of

moderate obesity can be managed by allowing the

children to grow into their present weight.

0035 As 450 g of excess body weight represents 14.7 MJ,

a daily reduction of 2 MJ is needed to lose 450 g of

weight a week. Dietary restriction is not recom-

mended for infants under 18 months of age. Greater

affluence will inevitably mean than an ever-increasing

number of youths will be obese, with all the asso-

ciated phenomena. Determined educational and

nutritional efforts must be adopted to avoid this

scourge of life in privileged communities.

Protein–Energy Malnutrition (PEM)

0036Formerly known as protein–calorie malnutrition,

PEM is a major global problem and one which

arouses much controversy even in terms of its classi-

fication. Although PEM is rare in adults, it is respon-

sible for a high mortality and indeed morbidity

amongst children in developing countries. At one

end of the spectrum PEM includes marasmus, and at

the other the distinct syndrome of kwashiorkor, with

intermediate deficiencies between both polarities.

(See Protein: Deficiency.)

0037Within this band there are deficiencies of specific

dietary constituents, particularly folate and vitamin

A. Many children with severe PEM have infestations

due to Giardia lamblia, Strongyloides stercoralis,or

Ascaris lumbricoides. Tuberculosis, bronchopneumo-

nia, and measles are significant secondary complica-

tions.

0038Anorexia plays a dominant role in PEM, as does

the presence of small-bowel mucosal atrophy. These

phenomena may be accompanied by the presence of

both a protein-losing enteropathy and iron deficiency.

(See Anorexia Nervosa.)

0039These disorders can be grouped together. Some

workers regard marasmus as a successful adaptation

to nutritional stress, and kwashiorkor as the failure of

such an attempt. A comparison of kwashiorkor and

marasmus is given in Table 1.(See Kwashiorkor;

Marasmus.)

0040Malnutrition and its associated infections cause the

death of many millions (Figure 2).

0041PEM is not limited to nonindustrialized countries.

Fad and strict vegetarian diets as well as medically

unsupervised elimination regimes all have the poten-

tial for causing PEM. (See Vegetarian Diets.)

tbl0001Table 1 Comparison of marasmus and kwashiorkor

Marasmus Kwashiorkor

Weight ### ##

Edema  þþþ

Depigmentation  """

Hair changes + þþ

Vitamin levels ### ##

Small intestine – villous atrophy þþ þþþ

Lactase, sucrase, maltase ## ###

Pancreatic enzymes ##

Fatty liver þþ

#, slightly reduced; ##, moderately reduced; ###, markedly reduced.

Modified from Gryboski J and Walker WA (1983) Gastrointestinal Problems

in the Infant, 2nd edn. Philadelphia: WB Saunders.

1154 CHILDREN/Nutritional Problems

0042 Lack of nutritional knowledge and financial re-

sources within a household, the community or

society at large is responsible for the appalling child-

hood mortality and morbidity seen in PEM. Malnu-

trition ought to be regarded as the consequence

of adverse social and economic conditions rather

than a primary medical problem. Simple measures,

such as the encouragement of breast-feeding, per-

sonal hygiene, improved sanitation, and the establish-

ment of adequate and safe drinking water, would do

much to prevent the many potentially hazardous

enteric infections seen in malnourished infants and

children.

Food Fads

0043 Food fads are not only potentially dangerous for

adults but also particularly hazardous in childhood.

Apart from human milk for babies and young infants,

there is no other single food which supplies all nutri-

tional needs, yet food faddism seems increasingly

attractive to many seeking ‘healthy foods’ and a diet

free of all alleged contaminants.

0044 As food technology and supermarket retailing

become more sophisticated and food processing is

seen as an adulteration of our food, some will seek

alternatives via the use of ‘natural, organic, and

health foods’–all loose terms. There is an organic

food myth and we do not even have an acceptable

definition of ‘organic foods’–a term introduced

by the late JI Rodale. Consumers presume such

food is grown in soil free of artificial fertilizer, is

pesticide-free, and does not contain additives, preser-

vatives, hormones, or antibiotics. In northern Europe,

70% or more of all foods now consumed is processed,

preserved, and/or packaged. There is no evidence to

support the contention that ‘organic foods’ are

healthier for the consumer.

0045Synthetic vitamins are as effective as natural vita-

mins. Food grown in rich soil is not nutritionally

dissimilar to that found in poor soil. Unfortunately,

disinformation by the healthy-food movement has

facilitated the public acceptance of food mythology

as a reality. Nutrition is a subject that is ill under-

stood. (See Organically Farmed Food.)

0046Tragically, children have died from malnutrition

when fed weird and unconventional diets. Growth

failure and anemia were found in a small group of

infants fed a formula of barley water, corn syrup, and

whole milk.

0047Faddism can result in many diverse and potentially

dangerous outcomes. There are those who expect

their children to survive solely on fruit (fruitarians);

others are committed to a diet of raw foods. The

discovery of fire 40 000 years ago by primitive

humans via our ancestors brought an end to reliance

on diets comprised solely of raw food. Some un-

cooked foods are toxic and unsafe, e.g., meat might

become contaminated by bacteria, and raw foods may

contain substances that interfere with vitamin B

(antihistaminases). Raw red kidney beans possess nat-

ural toxins (hemagglutinins). The Zen-macrobiotic

diet has been associated with deaths. The ever-

increasing restrictive nature of this diet is such that

Bile salt

deconjugation

Bacterial toxins

Gastroenteritis

Infection

High osmotic load

Intestinal

hurry

Decreased

appetite

Pancreatic and/or

intestinal malfunction

Pancreatitis,

primary lactose

intolerence, gluten

intolerance, etc.

Excess luminal

water

Small-bowel

stasis

Loss of protein

sugars, fats.

DIARRHEA

MALABSORPTION

MALNUTRITION

fig0002 Figure 2 The vicious cycle of diarrhea and malnutrition. Courtesy of WF Balistreri.

CHILDREN/Nutritional Problems 1155