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swallow. Nausea and vomiting are followed by severe

diarrhea. A characteristically symmetric dermatitis,

especially on the exposed surfaces of the body

(hands, forearms, elbows, feet, legs, knees and neck),

appears. The dermatitis is sharply separated from the

surrounding normal skin. At first, the skin becomes

red, somewhat swollen, and tender, resembling a mild

sunburn. If the condition is untreated, the skin be-

comes rough, cracked, and scaly, and may become

ulcerated. Sunshine and exposure to heat aggravate

the dermatitis. Some neurologic symptoms like

confusion, dizziness, poor memory, and irritability,

leading to hallucinations, delusions of persecution,

and dementia, are also noted as the severity increases.

The classic ‘Ds’ are the final stages of the disease –

dermatitis, diarrhea, dementia, and death.

0055 The patient should be confined to bed until conva-

lescence is well under way. Specific therapy consists

of the oral administration of a sufficient amount of

niacinamide daily. In conjunction with specific

niacinamide therapy and supportive multivitamin

(particularly vitamin B complex) supplementation, a

well-balanced diet is given, containing 100–150 g of

high-quality protein (preferably from meat, milk, and

eggs) and provides about 3500 cal. In case of gastro-

intestinal symptomatology, the diet initially should be

a full liquid diet devoid of roughage. As the patient

improves, a general diet high in good-quality proteins

is given.

Disorders Resulting from Deficiency of other

Nutrients

0056 In addition to vitamins, there are many other nutri-

ents whose deficiency in the diet can lead to several

important human diseases. Some of these nutrients

include iron, folic acid, iodine, calcium, phosphorus,

protein, calorie, etc. The diseases resulting from a

deficiency of these nutrients, along with the symp-

toms and methods of treatment, are as follows:

0057 Anemia Anemia is a deficiency in the circulating

hemoglobin and results from inadequate synthesis of

hemoglobin or of red blood cells or both. It is caused

by an inadequate supply of one or more nutrients

such as iron, vitamin B

, folic acid, vitamin C, and

trace elements, or by many non-dietary factors such

as blood loss, excessive blood destruction, or defects

in blood formation.

0058 Iron-deficiency anemia is the most common disease

in different parts of the world and occurs more fre-

quently in infants, preschool children, adolescent

boys and girls, and women in childbearing years

(Figures 1 and 2). Insufficient iron in the diet, faulty

absorption of iron from the small intestine, and blood

loss are causes of iron-deficiency anemia.

0059The symptoms of nutritional deficiency disease

include weakness, fatique, pallor, dyspensia on

exertion, and a constant feeling of tiredness. The

onset is usually insidious. There may be vague gastro-

intestinal symptoms, and achlorhydria is not uncom-

mon. The skin, mucous membrane, and nails are pale

in proportion to the reduction in the circulating

hemoglobin. Many adults with hypochromic anemia

exhibit atrophy of the papillae of the tongue. There

may be a slight cardiac enlargement, with eventual

failure if the anemia becomes severe. Nails may be

brittle, longitudinally ridged, or even concave and

spoon-shaped. Individual blood cells are pale (hypo-

chromic) and smaller than normal (microcytic).

0060Many instances of nondeficiency anemia can be

prevented by appropriate diet. Once anemia is pre-

sent, treatment requires iron salts such as ferrous

sulfate, although attention should also be focused on

correcting a faulty diet. Good sources of iron include

meats, especially offal, whole-grain breads and

cereals, as well as dark green leafy vegetables.

0-4 Years

Percent

5-14 Years Nonpregnant

women

Pregnant

women

Men Elderly

Develo

countries Industrialized countries

fig0001Figure 1 Prevalence of anemia by age group in industrialized

and developing countries, 1998. Source: ACC/SCN (2000) Fourth

Report on the World Nutrition Situation. Geneva: WHO.

Percent

Africa

Americas

South-East

Asia

Europe

Eastern

Mediterranean

Western

Pacific

fig0002Figure 2 Prevalence of anemia in children 0–5 years old by

WHO region, 1998. Source: ACC/SCN (2000) Fourth Report on the

World Nutrition Situation. Geneva: WHO.

3664 MALNUTRITION/The Problem of Malnutrition

006 1 Anemia in infancy can be easily prevented by using

an iron-fortified formula throughout the first year or

introducing iron-rich foods, such as cereals, early

and continuing their use throughout childhood. The

requirements of pregnant women can be met only by

using an iron supplement.

0062 Kwashiorkor and marasmus These are diseases of

protein-calorie malnutrition, which includes a wide

spectrum of disturbances ranging from mild deficiency

to the severe forms of kwashiorkor and marasmus.

The disease is widely prevalent in the tropical and

subtropical underdeveloped parts of the world and is

a major health problem of young children among the

poor strata of the population of those areas.

006 3 The term ‘kwashiorkor’ means ‘the evil spirit that

infects the first child when the second child is born.’

In the developing and underdeveloped countries,

babies are usually breast-fed until 18–24 months of

age, and occasionally longer. When another baby

is born, the older child generally subsists on the

foods typical of the household – usually a high-

carbohydrate, low-protein diet, and this results in

the symptoms of kwashiorkor.

006 4 The symptoms start to appear after a few months

of weaning. The increase in stature and tissue devel-

opment is retarded, and the muscles become flabby

and lose their tone. The severe protein levels are

reduced so that the tissues hold water, especially evi-

dent by the swollen face and legs, and the large pot-

belly. The hair often changes color, appears lifeless,

and can be easily plucked out. Diarrhea is frequently

observed probably as a result of poor sanitation in the

home. The child with diarrhea advances rapidly from

mild to severe kwashiorkor.

006 5 Marasmus is another protein-calorie-deficient dis-

ease prevalent mostly in the urban areas of developing

countries, where infants are usually weaned from the

breast at a much earlier age (before 1 year) than in

rural areas. The result is severe growth failure and

emaciation in the first year of life. Muscle wasting is

extreme, and subcutaneous fat is absent, so the ribs

become visible. Retarted mental development is likely

in children suffering from marasmus, as deprivation

of protein occurs at a time when the division of brain

cells occurs most rapidly.

0066Treatment of the above diseases is based on the

administration of proteins of high biological value

and correction of any existing dehydration and elec-

trolyte imbalance. A diet rich in milk protein has been

the treatment of choice. Fruit juice, eggs, meat, vege-

tables, and cereals are gradually added to the diet

throughout the period of recovery. Several inexpen-

sive vegetable and animal protein mixtures have also

been developed on a regional basis for human feeding

that increase the quantity and improve the quality of

dietary protein.

0067Endemic goiter Endemic goiter is an iodine-

deficiency disease (IDD) that occurs in those areas

where the iodine content of the soil is so low that

insufficient iodine is obtained through food and water

and occurs when no provision is made for supplying

iodized salt.

0068A lack of iodine leads to an increase in the size and

number of epithelial cells in the thyroid gland and

thus an enlargement of the gland. This condition is

known as simple or endemic goiter and presents no

other abnormal physical findings. The deficiency is

more prevalent in females than males and is more

frequent during adolescence and pregnancy. Tables 2

and 3 list the number of countries affected and the

current magnitude of IDD.

0069Consumption of iodized salt is the most common

treatment of this disease. Some natural sources of

iodine like sea foods (fish, crabs, etc.) and green vege-

tables grown in marine soil can also provide sufficient

amounts of iodine in the body.

tbl0002 Table 2 Number of countries affected by IDD, 1999

Total number of

countriesinregion

Countries where IDDis

a public healthproblem

Countries where IDDhas

been eliminated

or is

nonexistent

Countries with

insufficient data

Region

Africa 46 44 1 1

Americas 35 19 3 13

South-east Asia (including India) 10 9 0 1

Eastern Mediterranean 22 17 1 4

Europe 51 32 13 6

Western Pacific (including China) 27 9 2 16

To t a l 191 130 20 41

IDD elimination is defined as a total goitre rate of <5% in school-age children.

Data are insufficient to categorize countries.

Source: ACC/SCN (2000) Fourth Report on the World Nutrition Situation. Geneva: WHO.

MALNUTRITION/The Problem of Malnutrition 3665

0070 It is thus clear that nutrition challenges continue

throughout the life cycle, as shown in Figure 3. Poor

nutrition often starts in utero and extends, particu-

larly for girls and women, well into adolescent and

adult life. It also spans generations. Undernutrition

occurring during childhood, adolescence, and preg-

nancy has an additive negative impact on the birth-

weight of infants. Low-birthweight infants who have

suffered intrauterine growth retardation as fetuses are

born undernourished and are at a far higher risk of

dying in the neonatal period or later infancy. If they

survive, they are unlikely to catch up significantly

on this lost growth late and are more likely to

experience a variety of developmental deficits. A

low-birthweight infant is thus more likely to be

underweight or stunted in early life.

0071The consequences of being born undernourished

extend into adulthood. Epidemiological evidence

from both developing and industrialized countries

now suggests a link between fetal undernutrition

and an increased risk of various adult chronic diseases

– the ‘fetal origins of disease hypothesis.’

See also: Anemia (Anaemia): Iron-deficiency Anemia;

Ascorbic Acid: Properties and Determination;

Carotenoids: Occurrence, Properties, and

Determination; Cholecalciferol: Properties and

Determination; Iodine: Iodine-deficiency Disorders;

Malnutrition: The Problem of Malnutrition; Obesity:

Etiology and Diagnosis; Riboflavin: Properties and

Determination; Scurvy; Thiamin: Properties and

Determination; Vitamins: Overview

tbl0003 Table 3 Current magnitude of IDD, 1999

Region Population

(million) Population affected bygoitre At-risk population

Million Percentage of regional population Million Percentage of regional population

Africa 612 124 20 295 48

Americas 788 39 5 196 25

South-east Asia 1477 172 12 599 41

Eastern Mediterranean 473 152 32 348 74

Europe 869 130 15 275 32

Western Pacific 1639 124 8 513 31

Total 5857 740 13 2225 38

Based on UN Population Division 1997 estimates.

Source: ACC/SCN (2000) Fourth Report on the World Nutrition Situation. Geneva: WHO.

Higher

mortality

rate

Inadequate

food, health,

and care

Higher

maternal

mortality

Inadequate food,

health, and care

Reduced

physical capacity

and fat-free mass

Inadequate food,

health, and care

Reduced

mental

capacity

ADOLESCENT

Stunted

CHILD

Stunted

Inadequate food,

health, and care

Frequent infections

Untimely/inadequate

feeding

Increased

risk of adult

chronic disease

Impaired

mental

development

Inadequate

catch-up

growth

Reduced capacity to

care for child

BABY

Low

birthweight

OLDER

PEOPLE

Malnourished

Inadequate

foetal

nutrition

WOMAN

Malnourished

PREGNANCY

Low weight gain

fig0003 Figure 3 Nutrition throughout the life cycle. Source: ACC/SCN (2000) Fourth Report on the World Nutrition Situation. Geneva: WHO.

3666 MALNUTRITION/The Problem of Malnutrition

Further Reading

ACC/SCN (2000) Fourth Report on the World Nutrition

Situation. Geneva: ACC/SCN.

Agarwal P (1998) Human Nutrition, Meal Planning,

Health Care and Common Diseases, p. 359. Calcutta:

Premier Publishing House.

Burton BT (1978) Human Nutrition, p. 530. New Delhi:

Tata McGraw Hill.

Delange F, de Benoist B and Alnwick D (1999) Risks of

iodine-induced hyperthyroidism after correction of

iodine deficiency by iodized salt. Thyroid 9: 545–556.

Hibbert V (1973) The five possible causes of all nutrient

deficiency. Illustrated by deficiencies of vitamin B

and folic acid. American Journal of Clinical Nutrition

26: 77–88.

Pelletier DL, Frongillo EA and Habicht JP (1993) Epidemi-

ological evidence for a potentiating effect of malnutri-

tion on child mortality. American Journal of Public

Health 83: 1130–1133.

Robinson CH (1978) Fundamentals of Normal Nutrition,

p. 596. New York: MacMillan.

Suharno D and Muhilal (1996) Vitamin A and nutritional

anemia. Food and Nutrition Bulletin 17: 7–10.

Tomkins A (2000) Malnutrition, morbidity and mortality in

children and their mothers. Procedures of the Nutrition

Society 59: 135–146.

Underwood BA (1998) Micronutrient malnutrition. Is it

being eliminated? Nutrition Today 33: 121–129.

Malnutrition in Developed

Countries

M Astier Dumas, Centre de Recherches Foch, Paris,

France

This article is reproduced from Encyclopaedia of Food Science,

Introduction

0001 Although food is available to excess in developed

countries, malnutrition is probably not infrequent,

even in people free of disease. Malnutrition in de-

veloped countries is not the same as malnutrition in

the developing world, where people are undernour-

ished. In developing countries malnutrition is gener-

ally characterized by deficiencies, such as vitamin and

mineral deficiencies.

0002 Paradoxically, in developed countries, overnutri-

tion leading to obesity, diabetes, or cardiovascular

diseases can coexist with nutrient deficiencies, and

fad diets can lead to an inadequate intake of nutri-

ents. Whether these deficiences can really lead to

diseases is not certain, but it is generally accepted

that they are undesirable.

0003In developed countries it may be more accurate

to speak of groups at risk of malnutrition than

of malnutrition itself, and it is necessary to include

overnutrition and undernutrition, depending on the

groups concerned.

0004Correlations between fat and energy intake and

obesity, diabetes, cardiovascular diseases, and cancer

have been thoroughly investigated. Beyond all the

discussions made on this point, there is general agree-

ment that excess calories, whatever their source, can

be a cause of disease ranging from cardiovascular

disease to cancer and diabetes. Changes in the com-

position of food eaten, towards processed foods rich

in fat, with a high energy density and poor nutritional

content, may be an important factor, as vitamins

and minerals are sometimes described as protective

factors (mainly vitamins A, C, and E, b-carotene and

selenium in studies of cancer and cardiovascular dis-

eases). (See Cancer: Diet in Cancer Prevention.)

0005There are few data on the nutritional status of the

obese subject compared to the nonobese, but in a

French study red blood cell transketolase activity – a

measure of thiamin status – was lower in obese

subjects of both sexes. (See Obesity: Etiology and

Diagnosis.)

0006Apart from diseases that produce malnutrition by

altering either digestive processes or the metabolic use

of nutrients (e.g., traumas, surgery, cancer, and

burns), malnutrition in developed countries can affect

poor people (often immigrants), old people, those on

weight-reducing diets, youngsters, those who are

unable to buy food or have difficulty eating it, those

on special diets, or those who eat for fun rather than

from hunger. Table 1 gives an estimation of the

tbl0001Table 1 Groups at risk of poor vitamin status in the US

population (estimation)

Group Percentage of

population

group at risk

Nutrients

Aged 10–19 years 14.6 Folates, vitamin A

Alcohol users 22 Vitamins B

, A and D,

carotene and folates

Smokers 28.6 Vitamins B

, E and C,

carotene and folates

Diabetics 4.6 Vitamins B

, C and D

Dieters 20 Potentially any or all

Elderly people (aged

over 65 years)

12.1 Vitamins C and D, folates

Oral contraceptive

users

10.4 Vitamin B

, folates,

carotene

Pregnant women 3.9 All, especially folates

Strict vegetarians >0.9 Vitamins B

and D

Reproduced from Gaby S et al. (1991) Vitamin Intake and Health: A Scientific

Review. New York: Marcel Dekker, with permission.

MALNUTRITION/Malnutrition in Developed Countries 3667

percentage of population groups at risk of vitamin

deficiency in the US population.

Evidence from Consumption Data

0007 Many surveys have been made on food consumption

levels, comparing the results with dietary reference

values (DRVs) or recommended dietary allowances

(RDAs) in the various countries. However, the fact

that the RDA is not attained by a small fraction of the

population does not mean that these people are mal-

nourished. The RDAs are supposed to cover the needs

of almost all the population, and a level of intake that

is inferior by 20%, or even by 40%, can still be

compatible with adequate nutrition. It is necessary

to know the physiological status of these people in

order to understand the meaning of an inadequate

intake. For example, a serum level of a nutrient that

is inferior to the reference level (biochemical index) is

not automatically a sign of disease, but its signifi-

cance is more reliable than the level of food consump-

tion. In some instances the physiological signs of

deficiency are difficult to obtain on a large scale in

surveys. For example, identification of good bone

health – the bone mass – is not easy to study, and

calcium intake is therefore used to identify the popu-

lation at risk. The percentage of the population with

intakes of calcium well below the RDA is sometimes

important: in Belgium, inadequate intakes were

found in 67% of 13–19-year-olds, 73% of 9–12-

year-olds, and 85% of 5–8-year-olds. It has been

shown that the proportion of girls aged 11–19 years

consuming less than 1200 mg of calcium per day is

91% in Portugal, 85% in the USA and 78% in

Canada. Between 1980 and 1985 in the UK the

mean daily intake of calcium fell from 960 mg

per day to 850 mg per day; 33% of boys (10–11

years) and 53% of girls (same age), and 25% of

boys and 57% of girls (14–15 years) were found

to have intakes of calcium below 800 mg per day.

Evidence suggests that the bone mass of an adult

is largely influenced by the calcium intake during

adolescence, indicating that these population

groups are at risk of bone disorders later in life.

(See Dietary Surveys: Measurement of Food Intake;

Surveys of National Food Intake; Nutritional Assess-

ment: Anthropometry and Clinical Examination;

Nutritional Surveillance: In Industrialized Countries;

Dietary Reference Values; Dietary Requirements of

Adults.)

Evidence from Biochemical Data

0008 Biochemical evidence given by serum levels is avail-

able for many nutrients, mainly vitamins but also for

iron. (See Nutritional Assessment: Biochemical Tests

for Vitamins and Minerals.)

Elderly People

0009The reasons for malnutrition in the elderly are numer-

ous and can coexist. They include the following: lack

of money to buy food; poor dentition; depression and

loneliness; inadequate exposure to sunlight in house-

bound elderly people, leading to poor vitamin D

status; lack of appetite; effects of drugs; loss of dex-

terity of hands, hindering food preparation; and,

sometimes, disease. Some elderly people are on self-

or medically prescribed diets unsuited to their needs.

(See Elderly: Nutritional Status; Nutritionally Re-

lated Problems.)

0010Food intake is generally lower in institutionalized

elderly people than in free-living elderly people.

Drugs are more commonly taken and depression is

more frequent in institutionalized elderly people.

Results of biochemical studies in institutions show

generally lower serum vitamin levels than for free-

living elderly people. Nevertheless, some general de-

ficiencies have been described in elderly people.

0011In the Dutch elderly population study published in

1990, anemia according to the criteria of the World

Health Organization (WHO) was found in 4% of

men and 1% of women. Frank nutritional deficien-

cies were not observed, but compared to younger

adults a substantial percentage of the elderly had

relatively lower values of folate (men, 30% below

5 nmol l

1

; women, 17% below 5 nmol l

1

), pyridoxal

phosphate (men, 43% below 19 nmol l

1

; women,

13% below 19 nmol l

1

), total carotenoids (men,

22% below 1 mmol l

1

; women, 13% below

1 mmol l

1

), and 25-hydroxyvitamin D. It was under-

lined that ‘since the health consequences of these low

levels at old age are unknown, no conclusion can be

drawn whether this indicates marginal status among

these elderly.’ Elderly people following a vegetarian

diet were more at risk of iron, zinc, and vitamin B

deficiencies.

0012In one study in France of 70 institutionalized

elderly people, 24% of subjects had biochemical

signs of malnutrition (low serum proteins and hemo-

globin values). The energy consumption of these sub-

jects was below the RDA, as it was for iron, calcium,

and vitamin C, but not for protein. In another study

of 204 institutionalized patients (convalescent eld-

erly), 65 were found to have low serum albumin

levels, 27 being severely malnourished. In 59 dis-

ease-free subjects in an institution it was found that

20% had serum folate deficiency. Later, 235 institu-

tionalized subjects were studied and 72.8% found

with folate deficiency and 11.4% with vitamin B

deficiency.

3668 MALNUTRITION/Malnutrition in Developed Countries

0013 In Belgium, the vitamin D status of 240 elderly

subjects was analyzed and it was concluded that

the deficiency of both the vitamin D substrate and

hormone was frequent in the elderly population in

Belgium.

0014 In Italy, the results of a nationwide study on nutri-

tional status of the elderly was published. Only 47%

of subjects were found to be free from vitamin defi-

ciencies, and three out of 10 had multiple vitamin

deficiencies. Vitamin B

and vitamin B

deficiencies

were most prevalent (25% and 20%), followed by

folate (15%) and vitamin C (14%). Vitamin A and

vitamin E deficiencies were negligible (6% and 2%).

In Naples, low intakes of calcium, iron, and nicotinic

acid, and a low status of vitamin B

for 20% of men

and women, and low riboflavin status for 40% of

men and 20% of women were reported.

0015 In the USA, a biochemical study of 70 women

found 14% of all subjects deficient or low in vitamin

A, 17% low in vitamin B

, and 15% low in vita-

min B

. Serum ascorbic acid levels were acceptable,

but low or deficient levels of total serum protein and

albumin were observed for 36% and 20% of the

subjects; low hemoglobin and elevated total iron-

binding capacity values were recorded for 19% and

40% of subjects. In other surveys in the USA, Sweden

and Netherlands, a prevalence of iron-deficiency

anemia, instances of potassium deficiency, and pos-

sible vitamin D and/or calcium deficiency – with or

without osteoporosis – have been observed.

0016 Obviously the situation can be worse in poor eld-

erly people. Folacin, iron status, and hematological

parameters of 193 people from urban low-income

households in Florida were reported and, of these

subjects, 60% could be classified as high risk for

folacin levels (under 140 ng ml

1

) and 11% at

medium risk (< 160 ng 1

1

). An incidence of 14% of

anemia and 32% of leukopenia, with no iron

deficiency, was found.

Adults

0017 In one recent study in France, in a sample of 1039

subjects aged from 6 to 97 years, from a defined area,

no major deficiency in vitamin A was reported – less

than 3% of serum levels were in the range indicating

high risk of anomalies, but approximately 20% of

women showed moderate risk. For vitamin E, slight

deficiencies are more frequent in young people. For

vitamin C, around 10% of men and less than 5% of

women can be considered at high risk, with three

times more at moderate risk. For vitamin B

, erythro-

cyte transketolase activity corresponding to a high

risk of deficiency was found in 22% of adults. For

vitamin B

the risk was judged high in up to 31% of

women and 22% of men. For vitamin B

, high risk

was present in up to 16% of men and 25% of women.

Only 60% of the population showed no biochemical

defect related to any vitamin deficiency.

0018The authors of this report underlined the correl-

ation between tobacco smoking, alcohol con-

sumption, use of oral contraceptives, and vitamin

status. (See Alcohol: Metabolism, Beneficial Effects

and Toxicology; Contraceptives: Nutritional Aspects;

Smoking, Diet, and Health.)

0019The most documented nutrient is iron. In Germany

diminished iron body stores in a considerable propor-

tion of blood donors were found. An incidence of 9%

of completely exhausted iron stores in male blood

donors was reported – a figure also observed in Scan-

dinavia. An even higher rate was found in female

blood donors (25%).

Women of Child-Bearing Age and Infants

0020Studies in North America and Scandinavia show that

1–6% of women of child-bearing age (for men in the

same age range only 1–2%) are anemic. In France, in

one group studied, 2–3% of women and up to 25% of

pregnant women were anemic. In Germany, it was

reported that 10% of pregnant women had iron

deficiency during the first trimester and 50% had

iron deficiency at the end of pregnancy.

0021Iron deficiency is also a problem in infants. A 10%

incidence of anemia and a 40% borderline iron status

was found in 10–12-month-old infants in France.

0022Rickets still exists in developed countries. Despite

supplementation of infant formulae with vitamin D,

and the drops prescribed daily to infants when this

supplementation is not made, some groups at risk

have been identified. These include the following:

native Indians in Canada because of poor lifestyle,

lack of exposure to the sun, and lack of vitamin sup-

plementation; the Asian population in the UK; Turk-

ish and Moroccan infants in the Netherlands; and, in

France, infants with dark skin coming from Africa.

(See Infants: Nutritional Requirements.)

0023Another population group at risk is that eating a

macrobiotic diet. Fifty-three Caucasian infants aged

10–20 months were compared to 57 matched omniv-

orous infants in the USA. Of the children in the

former group, 55% had rickets, and the 25-hydroxy-

vitamin D level was 34 nmol l

1

(sd 15.3) against

49.7 nmol l

1

(sd 21.9) in the control group. (See

Macrobiotic Diets.)

Children

0024Although some real cases of severe malnutrition

(kwashiorkor) have been described in North America

or Europe, these are limited to instances in which a

deliberate deviation from normal infant practices is

made, sometimes for pseudophilosophical purposes

MALNUTRITION/Malnutrition in Developed Countries 3669

(e.g., by sects). (See Children: Nutritional Require-

ments.)

0025 Dutch children fed macrobiotic diets were com-

pared to omnivorous children (controls) for iron,

vitamin B

, and folate status. Iron deficiency was

observed in 15% of the macrobiotic group (none in

the control group: P ¼0.003). Plasma vitamin B

concentrations in the macrobiotic group were far

below those of the control group (P < 0.001), and

plasma folate concentrations were higher in the

macrobiotic group.

0026 The main nutritional problem in children is dental

decay. High consumption of sucrose in young chil-

dren is a characteristic feature of developed countries,

particularly in Anglo-Saxon countries, and less so in

Latin countries. In a communication in Edinburgh

in the UK, it was reported that in some children

aged 2–4 years the proportion of energy derived

from sugar was as high as 30%. The main source is

fruit juices, generally considered as ‘healthy’ drinks.

0027 A decrease of dental problems in children has

been observed over the past few years and this is

believed to result from: (1) supplementation of

water or salt (depending on the country) with fluor-

ide; (2) improved hygiene education; and (3) use of

sugar substitutes. However, dental decay remains

an important problem. (See Dental Disease: Role of

Diet.)

0028 An excess of sugars in children’s diets can also lead

to nutrient deficiencies, and one study found that 8%

of children had a high risk of vitamin B

deficiency.

0029 Biochemical data about the nutritional status

of healthy children are infrequently obtained, but

consumption studies arenumerous. The patternofcon-

sumption is rather similar in different countries, with

a high percentage of sugar and fat, and a relatively

low intake of calcium and iron.

0030 The consequences of these inadequate intakes are

not well known, although iron deficiency for preg-

nant and lactating women and their newborn babies

can be a consequence of insufficient intakes during

adolescence. Osteoporosis can be linked with devel-

opment of insufficient bone mass during adolescence.

It is also suggested that excessive fat intake during

childhood and adolescence may be instrumental in

the development of arteriosclerosis. (See Atheroscler-

osis; Osteoporosis.)

0031 These studies suggest that malnutrition in the de-

veloped world is mainly the result of poor food selec-

tion in affluent societies. The shift of consumption

from traditional basic foods towards convenience,

value-added foods can lead to higher intakes of

fat and sugar, and lower intakes of vitamins and

minerals.

0032Information and nutrition education would seem

to be the obvious approach to preventing these prob-

lems of malnutrition in developed countries. Refer to

individual nutrient deficiencies.

See also: Children: Nutritional Requirements; Dental

Disease: Role of Diet; Dietary Reference Values;

Dietary Requirements of Adults; Dietary Surveys:

Measurement of Food Intake; Surveys of National Food

Intake; Elderly: Nutritional Status; Nutritionally Related

Problems; Infants: Nutritional Requirements;

Macrobiotic Diets; Nutritional Assessment:

Anthropometry and Clinical Examination; Biochemical

Tests for Vitamins and Minerals; Nutritional

Surveillance: In Industrialized Countries; Obesity:

Etiology and Diagnosis

Further Reading

Astier Dumas M and Lagrange Hanrez V (1982) L’alimen-

tation des personnes age

es: a

propos d’une enque

te dans

les hopitaux de long se

jour. Me

decine et Nutrition

XVIII(6): 359–376.

Bouillon RA (1987) Vitamin D status in the elderly: sea-

sonal substrate deficiency causes 1,25-dihydroxychole-

calciferol deficiency. American Journal of Clinical

Nutrition 45: 755–763.

Dagnelie PC et al. (1989) Increased risk of vitamin B

and

iron deficiency in infants on macrobiotic diets. American

Journal of Clinical Nutrition 50(4): 818–824.

ESVITAF (1986) Vitamin status in three groups of French

adults. Annals of Nutrition and Metabolism 30: S1.

Gaby S et al. (1991) Vitamin Intake and Health: A Scientific

Review. New York: Marcel Dekker.

Harrill I and Cervone N (1977) Vitamin status of older

women. American Journal of Clinical Nutrition 30:

431–440.

Hercberg S (1991) Iron and folate deficiency anaemias.

International Child Health II(2): 44–60.

INSERM (1983) Groups with high risk of iron deficiency in

industrialized countries. INSERM Meeting, Paris, 27–28

May 1983. Institut National de la Sante

et de la

Recherche Me

dicale en France.

Lowik MR et al. (1990) Nutritional Risk Assessment

among Dutch Elderly People. Report to the Netherlands

Ministry of Welfare.

Myers Nutrition Symposium (1986) Nutrition and Aging.

The 5th Bristol Myers Nutrition Symposium. New York:

Academic Press.

3670 MALNUTRITION/Malnutrition in Developed Countries

MALT

Contents

Malt Types and Products

Chemistry of Malting

Malt Types and Products

M J Edney and M S Izydorczyk, Canadian Grain

Commission, Winnipeg, Manitoba, Canada

Introduction

0001 Malt is a natural food product produced by germin-

ating grains and pulses. The three steps of malting,

steeping, germinating, and kilning, can be altered to

produce different types of malt. Barley malt is by

far the most common malt, and its major use is in

the brewing of beer. Barley malts are also used in

the production of spirits, vinegar, bread, breakfast

cereals, and several other minor products (Table 1).

In many parts of the world, sprouted cereals and

pulses are eaten directly for the improved availability

of their nutrients.

Malting

0002 Malting is the controlled germination of grain or

pulses. Proper control of its three major steps, steeping,

germination, and kilning, is essential if the desired end

product is to be produced without excess losses. A

range of malt products, with different constituents

and, as a result, different values for end-users, can be

produced by altering the conditions of the steps.

0003The steeping step hydrates the seed, which allows

germination to commence. Germination allows the

embryo to grow under controlled conditions, allowing

the seed to develop enzymes that degrade or modify

endosperm structure. Other enzymes hydrolyze and

solubilize the reserve starch and protein of the endo-

sperm. The amount of solubilized material, often re-

ferred to as ‘extract’ is an important quality parameter

that is used to predict the amount of beer or spirits a

malt can produce. Kilning is the final stage of malting,

and it halts growth of the embryo by removing mois-

ture. Temperatures and timelines used in kilning are

especially important because they determine the final

enzyme contents of a malt, the development of

desirable flavors, aromas, and colors, as well as the

concentration of undesirable flavors and aromas

(Table 2).

0004Barley is the seed most often malted, be it for

brewing, distilling, or the food industry. There are

several reasons for barley’s popularity in addition to

simple tradition. The presence of a hull on barley

protects the embryo during processing, strengthens

the texture of steeped kernels, and serves as a filtration

medium during brewing. Barley produces high levels

of enzymes during germination, and the endosperm is

easily degraded. Finally, the relatively low gelatiniza-

tion temperature (c.59–63



C) of barley malt starch

allows the heat-labile, starch-degrading enzymes from

malt to remain somewhat active and hydrolyze the

gelatinized starch. The result is a greater release of

fermentable sugars compared with malts of grains

with higher gelatinization temperatures. However,

several other grains, including wheat, sorghum, rye,

triticale, and oats, continue to be malted commercially

for both traditional and practical reasons.

Malt Uses

Brewing

0005The brewing industry is the largest user of malt, and

malt is arguably the most important ingredient in

tbl0001 Table 1 Major uses of malted grains and pulses and

contributions of the malts to the end-uses

Use Major contributions of malt

Brewing beer 1. Source of fermentable sugars

2. Source of enzymes

3. Source of flavor and color

Malt distilling 1. Source of fermentable sugars

2. Enzymes

3. Peat flavor

Grain distilling 1. Source of enzymes

2. Source of fermentable sugars

Baked products 1. Source of enzymes

2. Source of flavor and color

3. Source of fermentable sugars

Breakfast cereals 1. Source of flavor, including

sweetness, and color

Vinegar 1. Source of fermentable sugars

2. Source of enzymes

Germinated seeds

and pulses for food

1. Source of readily available nutrients

(amino acids and vitamins)

MALT/Malt Types and Products 3671

beer. Malt is the major supplier of the fermentable

sugars that are converted to alcohol by the yeast. The

malt provides not only a sugar source, starch, but also

the enzymes (i.e., a-amylase, b-amylase and limit

dextrinase) to degrade the starch into fermentable

sugars (i.e., glucose, maltose, and maltotriose). Yeasts

do not produce these enzymes. The malt enzymes are

even more important in adjunct brewing, where they

hydrolyze not only the malt starch but also the starch

of adjunct sources.

0006 Malt supplies other essential nutrients for yeast

growth. Yeasts require a source of nitrogen, but they

lack the enzymes necessary for degrading proteins

into products that they can assimilate. Therefore,

barley protein needs to be degraded, during malting

and brewing, into amino acids and peptides that the

yeast can use. Vigorous yeast growth is also depend-

ent on the supply of vitamins from malt including

biotin, myo-inositol, pantothenic acid, vitamin E,

folic acid, nicotinic acid, and thiamin. (See Beers:

Biochemistry of Fermentation.)

0007 Malt provides several components that affect beer

quality. The mouth feel or body of beer is an import-

ant characteristic that is dependent, to a large extent,

on the presence of dextrins in the beer. Dextrins are

small fragments of starch that have not been degraded

into fermentable sugars. Many beer types require a

higher concentration of dextrins in order to develop

a characteristic fullness. In contrast, many light, re-

freshing beer types require less body, and therefore,

adjuncts are used that can result in a beer with fewer

dextrins. Adjunct brewing can also be used to lower

the cost of beer production. Low-calorie beers also

require limited amounts of unfermentable dextrins in

order to reduce the calorie content. Beers featuring

less body require malts with higher levels of starch-

degrading enzymes.

0008Several other properties of beer are also dependent

on malt constituents. Malt supplies specific proteins,

such as Z-protein, that support a good, stable foam

or head in the final product. Reducing agents, such

as Maillard products, scavenge oxygen in the beer,

which increases the flavor stability. Flavor and color

compounds, mainly Maillard products produced

during kilning, are essential for developing the unique

aroma, taste, and color of beer. (See Browning: Non-

enzymatic.)

0009Some malt constituents have undesirable effects on

beer or its processing. Certain proteins and polyphe-

nols can cause hazes in the final product. Increased

levels of nonstarch polysaccharides, for example

b-glucan, can result in problems with beer filtration

and hazes in the final product. Other components

of malts, such as dimethyl sulfide, are sometimes

tbl0002 Table 2 Malting steps and conditions, and their effects, in producing different types of malts

Malting steps Conditions Options Effects

Steeping

Barley placed under water

Periodic air rests to allow

the grain to breathe

Moisture content at end of

steeping can vary from 42 to

48% (c. 24–48 h)

The higher the moisture, the greater the

potential to modify

Barley begins to germinate

Germination

Barley grows at controlled

temperatures with a good

flow of moist air

Germination can last from 4

to 7 days

Longer germination time gives better

modification

Temperatures can vary from

12 to 20



Higher temperatures give better

modification but greater malt losses

Temperatures can be raised

and air flows reduced

towards the end of

germination

Raising temperatures and reducing air

flows at the end of germination can increase

levels of free amino acids and simple

sugars

Withering (Kilning:

Phase I)

Green malt is dried to a

moisture level of 10%

Temperatures can vary from

45 to 65



Lower temperatures increase enzyme

activity

Rate of air flow can vary

Amount of recirculated air

can vary

Fast air flows with no recirculation dry the

malt quickly, restricting any additional

modification

Slow flow rates with recirculation allows the

malt to stew producing free amino acids and

simple sugars

Sealed containers with warm temperatures

lead to starch conversion

Curing (Kilning:

Phase II)

Moisture content is further

reduced to less than 6%

Temperatures can vary from

65 to 250



It is at this stage that simple sugars and

amino acids or small proteins combine in

the Maillard reaction

Products provide color, flavor, and reducing

power

Hotter temperatures result in greater

production of Maillard products

3672 MALT/Malt Types and Products

considered to be off-flavors. Many of these problems

can be avoided through the use of appropriate

malting conditions.

Distilling

0010 The distilling industry uses malt to provide ferment-

able sugars and other nutrients for the yeast. In malt

distilling, where only malt is added to the mash, all

the fermentable sugars come from the malt. This is in

contrast to grain distillers, where adjuncts, such as

unmalted corn and wheat, are added to the mash as

a cheaper source of starch. The malt provides the

enzymes that convert the starch, whether from the

malt or the cooked cereal, into fermentable sugars.

In both types of distilling, malt provides other essen-

tial nutrients for the yeast such as free amino acids

and vitamins. These must be in higher concentrations

for grain distilling because the adjuncts provide only

starch, which dilutes the concentration of other nu-

trients from the malt. In contrast to brewing, distilling

malt provides no mouth feel or flavor to the final

product, and in fact, a malt with a low concentration

of unfermentable dextrins and limited flavor is

desired. The only exception is the peat flavor that

some malt distillers require in their malt.

0011 Some malt continues to be used in the production

of neutral spirits, such as gins, aqua vitae, or vodka,

where it provides enzymes for degrading starch in a

manner similar to grain distilling. Malt, usually in the

form of extract, is the source of fermentable sugars in

wine coolers, a recently developed alcoholic beverage

in North America.

Food

0012 Baked goods Fermented bakery foods are one of the

largest users of food malt. Malt leads to better pan

flow, increased loaf volume, as well as better crumb

structure and crust color in baked goods. The malt

supplies simple sugars, amino acids, vitamins, and

enzymes, all of which help promote yeast growth

during baking. Darker colored malts can also be

added for increased flavor or color.

0013 Malt is often included in cracker formulations to

improve fermentation and to aid in sheeting and

laminating. Malt also enhances the crust color of

crackers allowing for reduced baking times and

oven temperatures.

0014 Breakfast cereals Barley malt is the most prevalent

flavor material used in breakfast cereals. Most flavors

come directly from the malt, but some are formed,

during the processing of breakfast cereals, from the

simple sugars, peptides and amino acids supplied by

the malt. The simple sugars also provide sweetness

to the cereals. In contrast to most other uses of

malt, enzymes are undesirable in breakfast cereals.

Their presence causes flavor instability due to their

breakdown of starches during processing. As a result,

malts used in breakfast cereals have very low enzyme

levels with elevated levels of flavors and flavor

precursors.

0015Vinegar Malt is used as a source of nutrients, in-

cluding fermentable sugars, for yeast in the produc-

tion of some vinegars. The object is to produce the

maximum amount of alcohol, which requires a good

complement of starch degrading enzymes, especially

where adjuncts are used. In some cases, the mash is

even supplemented with microbial enzymes. Bacteria

are eventually used to convert the alcohol into acetic

acid.

Other

0016Malt is also used in a range of other products. It is

added to the diet formulation of both infants and the

elderly because of the increased availability of nutri-

ents in malt, such as amino acids, simple sugars, and

vitamins. Malt enzymes can also increase the avail-

ability of nutrients from other ingredients in the diet.

Malt is used as a carrier in pharmaceutical products

where it increases palatability. Roasted malts are used

as the basis for various hot drinks including the

production of instant drinks from spray-dried malt

extracts. The price of malt restricts its use in feed

formulations, but limited amounts are used to

increase palatability of pig starter diets and pet

formulations.

Malt Types and Products

Pale Lager Malt

0017Pale lager malts are the most common type of malt.

They are the major ingredient in the light lager beers

that are so popular around the world. These beers

require a malt with maximum extract and good

enzyme potential but with limited development of

color and flavor (Table 3). Pale lager malts are gen-

erally made from two-rowed barley with average

levels of protein. In markets with high adjunct use,

such as the USA, high protein, six-rowed barley is

malted in order to ensure good enzyme potential

and adequate levels of amino acids for yeast nutrition.

Cheaper pale lager malts can be made from six-

rowed, European, winter barleys for price sensitive

markets.

0018Pale lager malts are well-modified and kilned gently.

The gentle kilning conditions, with an upper tempera-

ture of 85



C, produce a malt with high levels of

enzymes and a low potential for color development.

MALT/Malt Types and Products 3673