is found in:
|Fructose is a natural sugar
found in fruit, vegetables, and honey.23 Although all
fruit (especially fruit juices) contains fructose, the varying amounts
of fructose, glucose and sorbitol in different juices may affect
absorptive capacities (as demonstrated above with apple, pear and
grape juice).8 Because the concentration of the sugars
(glucose, fructose and sucrose) in fruit juice is influenced by
storage and the particular types of fruit (for example, type of
apple) used, each juice will differ in concentration of the different
Also, fruit juice manufacturers
around the world may use different methods in processing; they
may use different concentrations of fruit juice; adding or not
adding, for example, deflavoured apple juice, which may be imported
or produced locally. Thus, the concentrations of sugars in fruit
juices may differ extensively from country to country.
|It must be borne in mind that relatively
low doses of processed (commercial) fruit juice may cause as much
malabsorption as eating excessive amounts of fresh fruit.
Fructose is widely used as a food
additive, as it gives many useful attributes to food and beverages,
including sweetness, flavour enhancement, humectancy, colour and
flavour development, freezing-point depression, and osmotic stability.24
sucrose and sorbitol in foods
from Shaw V, Lawson M. Clinical Paediatric Dietetics. Blackwell
Science Ltd, UK, 1994.)
from the whole food sources, fructose, sucrose and sorbitol
is used in many manufactured foods. So much so that very few
manufactured foods are allowed in the diet. Sugar is used in
obvious products such as sweets, desserts and soft drinks, but
also in many other less obvious products such as canned food,
bottled sauces, savoury biscuits, etc.
is another potential trace source of these sugars as they are
sometimes used as carriers for flavouring compounds.
vegetables that contain predominantly starch are allowed in
the diet. Cooked vegetables have a lower fructose content and
are recommended in preference to raw as the cooking process
causes a loss of free sugars.
potatoes have a higher fructose content than old potatoes.
flour contains more fructose than white flour because the germ
and bran contains sucrose. Similarly other wholegrain foods
(e.g. brown rice and wholemeal pasta) contain more sucrose than
the refined products.
is used as an artificial sweetener, especially in diabetic foods
and drinks. These foods should therefore be avoided. Isomalt
and lycasin, alternative sweeteners that are predominantly used
in confectionary, also contain sorbitol. Glucose can be used
as an alternative sweetener and as a source of energy.
and sorbitol are used in medications as bulking agents or to
improve the taste.
Hereditary fructose intolerance
HFI is a rare autosomal recessive disorder
of fructose metabolism, due to a deficiency of fructose-1-phosphate
aldolase activity. This condition initiates severe toxic symptoms
following ingestion of fructose. Glycogen breakdown and glucose
synthesis can be inhibited, causing severe hypoglycemia, which
manifests as tremors, disorientation, vomiting and, in the worst
cases, severe convulsions and coma. Chronic ingestion of fructose
during infancy may also result in clinical findings such as failure
to thrive, hepatomegaly, and jaundice, which ultimately leads
to hepatic and/or renal failure and death. 5,25,26
is another form of fructose intolerance, which usually presents
as neonatal hypoglycemia. With fructose-1-phosphate aldolase deficiency,
hypoglycemia is experienced after fructose ingestion, whereas
in fructose-1,6-diphosphate deficiency, acidosis and hypoglycemia
are experienced during caloric deprivation, in fasting or during
MORE on FRUIT JUICE:
In general fruit juice…
(adapted from the American Academy of
Pediatrics' paper "The Use and Misuse of Fruit Juice in
- has no nutritional benefit for infants
younger than 6 months.
- has no nutritional benefit over fresh
fruit for children older than 6 months. In fact, fruit juice
contains less fibre than whole fruit; kilocalorie for kilocalorie,
fruit juice can be consumed more quickly than whole fruit;
and the reliance on fruit juice instead of whole fruit to
provide the recommended daily intake of fruits does not promote
the healthy eating behaviours associated with consumption
of whole fruits.
- is not appropriate in the treatment of
dehydration or management of diarrhoea. Malabsorption may
cause diarrhoea to worsen. Additionally, fruit juice is low
in electrolytes (with sodium concentrations of 1 - 3 mEq/L)
compared to oral electrolyte solutions (which contain 40 -
45 mEq/L). As a replacement for fluid losses, juice may predispose
infants to development of hyponatremia.
- is more than adequate in intakes of 120-180ml
per day (if well tolerated). Infants can be encouraged to
consume whole fruits that are mashed or pureed.
- should be given only to infants who
can drink from a cup. Teeth begin to erupt at approximately
6 months of age, and prolonged exposure of the teeth to the
sugars in fruit juice has been associated with the development
of dental caries.15
Other health concerns
related to fruit juice consumption:
Fruit juice has been shown to account for 50% of all
fruit servings consumed by children aged 2 through 18 years,
and 1/3 of all fruits and vegetables consumed by preschoolers.
With the increase in fruit juice consumption, there has been
an overall decline in milk intake, which is a cause for concern,
as milk is the major source of calcium in the diet. It was found
that 11% of healthy preschoolers consumed > or = 375ml/day
of fruit juice, which is considered excessive. Excess fruit
juice consumption has been reported as a contributing factor
to nonorganic failure to thrive and to decreased stature. In
other children, excessive fruit juice consumption has been associated
with an increased caloric intake and obesity.9
||compiled by Karen du Plessis B.Sc. Diet.
Food & Allergy Consulting & Testing Services (FACTS)
PO Box 565
E. Comments by
Chronic diarrhoea is a common complaint
in children. Often no cause is found despite extensive medical
investigations. In very young children soy and milk allergy
may be suspected or alternatively, lactose intolerance.
I see a number of adults and children, where a restriction
of dairy and soy products has not led to a resolution
of diarrhoea. Usually a careful history reveals an overconsumption
of hyperosmolar fluids, diet sweets, sweets, fruit
leathers or fruit. In some cases food intolerances
(histamine, salicylates) may play a role. In fructose
intolerance the first stools of the day are usually
formed and night-time diarrhoea is uncommon. When re-introducing
fructose into the diet, it is always an idea to challenge
in the pure form to establish a tolerance threshold. Should
there be no response to a low fructose diet, it can
be assumed that other food intolerances need to be investigated.
– Sabine Spiesser
case report demonstrates clearly that one should pay careful
attention to a patient’s history, and illustrates how modifying
an allergic child’s diet may have adverse consequences,
even if an ostensibly “healthy” food is the replacement.
- Dr. Harris Steinman
Prof Janice Joneja Ph. D.
Sabine Spiesser B.Sc. Dip. Ther. Diet.
Dr. Harris Steinman M.B.Ch.B.
For more information on this
subject and other allergy and intolerance related topics, visit:
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1. David TJ. Food and Food additive intolerance in childhood. Blackwell Scientific Publications, Oxford, 1993.
2. Gotze H, Mahdi A. Fructose malabsorption and dysfunctional gastrointestinal manifestations. Monatsschr Kinderheilkd 1993;141(4):276.
3. Talal AH, Murray JA. Acute and chronic diarrhea. How to keep laboratory testing to a minimum. Postgrad Med 1994;96(3):30-2.
4. Hyams JS, Leichtner AM. Apple juice. An unappreciated cause of chronic diarrhea. Am J Dis Child 1985;139(5):503-5.
5. Mahan LK, Escott-Stump S. Krause's Food, Nutrition and Diet Therapy 10th edition. W.B. Saunders Company, Philadelphia Pennsylvania USA, 2000.
6. M Gracey, N Kretchmer, R Ettore. Nestle Nutrition Workshop Series Vol 25. Sugars in Nutrition. Raven Press, New York, 1991.
7. Lifshitz F, Ament ME, Kleinman RE, et al. Role of juice carbohydrate malabsorption in chronic nonspecific diarrhea in children. J Pediatr 1992;120(5):825-9.
8. Smith MM, Davis M, Chasalow FI, Lifshitz F. Carbohydrate absorption from fruit juice in young children. Pediatrics 1995;95(3):340-4.
9. Dennison BA. Fruit juice consumption by infants and children: a review. J Am Coll Nutr 1996;15(5 Suppl):4S-11S.
10. Hoekstra JH, van den Aker JH, Ghoos YF, et al. Fluid intake and industrial processing in apple juice induced chronic non-specific diarrhoea. Arch Dis Child 1995;73(2):126-30.
11. Hyams JS, Etienne NL, Leichtner AM, Theuer RC. Carbohydrate malabsorption following fruit juice ingestion in young children. Pediatrics 1988;82(1):64-8.
12. Unrecognized Fructose Intolerance Often Underlies Unexplained GI Symptoms. 66th Annual Scientific Meeting of the American College of Gastroenterology.
13. Walker WA, et al. Pediatric Gastrointestinal Disease 2nd Edition, Vol 1. Mosby, Inc, USA, 1996. 14. American Academy of Pediatrics. The Use and Misuse of Fruit Juice in Pediatrics. Pediatrics 2001;107(5):1210-1213.
15. Ledochowski M, Widner B, Bair H, Probst T, Fuchs D. Fructose- and sorbitol-reduced diet improves mood and gastrointestinal disturbances in fructose malabsorbers. Scand J Gastroenterol 2000;35(10):1048-52.
16. Duro D, Rising R, Cedillo M, Lifshitz F. Association between infantile colic and carbohydrate malabsorption from fruit juices in infancy. Pediatrics 2002;109(5):797-805.
17. Behrman RE, Kliegman RM, Jenson HB. Nelson Textbook of Pediatrics 16th edition. W.B. Saunders Company, Philadelphia Pennsylvania USA, 2000.
18. Cohen SA, Hendricks KM, Eastham EJ. Chronic Nonspecific Diarrhea, A Complication of Dietary Fat
Restriction. Am J Dis Child 1979;133:490-2.
19. Hoekstra JH, van den Aker JH, Hartemink R, Kneepkens CM. Fruit juice malabsorption: not only fructose. Acta Paediatr 1995;84(11):1241-4.
20. Hoekstra JH, van Kempen AA, Kneepkens CM. Apple juice malabsorption: fructose or sorbitol? J Pediatr Gastroenterol Nutr 1993;16(1):39-42.
21. Kneepkens CM, Jakobs C, Douwes AC. Apple juice, fructose, and chronic nonspecific diarrhoea. Eur J Pediatr 1989;148(6):571-3.
22. Hoekstra JH, van Kempen AA, Bijl SB, Kneepkens CM. Fructose breath hydrogen tests. Arch Dis Child 1993;68(1):136-8.
23. Park YK, Yetley EA. Intakes and food sources of fructose in the United States. Am J Clin Nutr 1993;58(suppl):737S-47S.
24. Hanover LM, White JS. Manufacturing, composition, and applications of fructose. Am J Clin Nutr 1993;58(5
25. Rudolph AM. Pediatrics, 17th Edition. Appleton-Century-Crofts, Norwalk, Connecticut, 1982.
26. HFI Laboratory at Boston
27. CH Kempe, HK Silver, D O'Brien. Current Pediatric diagnosis and treatment, 7th Edition. Lange Medical Publications, Los Altos, California. 1982.
G. CPD Questions (for South African dietitians only)
PLEASE ANSWER ALL THE QUESTIONS
1. True or false: Fructose intolerance does not occur frequently in normal, healthy children and adults. (a.) True
2. The proposed mechanism for fructose absorption is as follows:
(a.) Against a chemical gradient
Against a concentration gradient
(c.) Facilitated transport via a carrier
(d.) Passive diffusion
3. Which statement is correct regarding fructose absorption?
(a.) Malabsorption is more apparent when the source is sucrose.
(b.) Absorption is more complete when the fructose concentration exceeds that of glucose.
(c.) Absorption is more complete when fructose and glucose are present in equal concentrations.
(d.) Absorption is more complete when fructose is ingested alone.
4. True or false: Unprocessed apple juice does not promote diarrhoea, compared to enzymatically processed apple juice.
(b.) False 5.
Which of the following has not been associated with fructose intolerance?
(a.) Increased incidence of dental caries
(b.) Abdominal pain, bloating and flatulence
(c.) Aversion to
sweet-tasting foods, including fruit
(d.) Early signs of mental depression
6. Which of the following does not contribute to the persistence of chronic non-specific diarrhoea?
(a.) Excessive fluid intake
(b.) Excessive fat intake
(c.) Excessive intake of carbonated fluids
(d.) Food poisoning
7. True or false: Fructose intolerance is generally not associated with failure to thrive, but hereditary fructose intolerance is.
8. Choose the correct statement regarding
(a.) It is recommended to infants younger than 6 months of age.
(b.) It has no nutritional benefit over fresh fruit in children older
than 6 months.
(c.) It is an appropriate treatment of dehydration.
(d.) An intake of 120-180ml per day is not adequate for infants.
|1. a [ ] b [ x ]
||2. a [ ] b [ ]
c [ x ] d [ ]
||3. a [ ] b
[ ] c [ x ] d [ ]
|4. a [ x ] b [ ]
||5. a [ x ] b [ ]
c [ ] d [ ]
||6. a [ ] b [ x ]
c [ ] d [ ]
|7. a [ x ] b [ ]
||8. a [ ] b [ x ]
c [ ] d [ ]
1. b. False
2. c. Facilitated transport via a carrier
3. c. Absorption is more complete when fructose and glucose are present
4. a. True
5. a. Increased incidence of dental caries
6. b. Excessive fat intake
7. a. True
8. b. It has no nutritional benefit over fresh fruit in children older
than 6 months.