Lactose Intolerance

A wide spread cause for digestive problems

By Christiane Pies, MSc
(Translated from German by Ute Marie Allison)

A case
Jane M. has been suffering from recurring digestion problems for years.
Repeatedly she gets diarrhoea, sometimes accompanied by vertigo or nausea. 
Then she has periods when she feels fine again, but all of a sudden her problems can reoccur.
Her diarrhoea attacks restrict her in her daily activities and she feels worse each year.
After many years she hears about the phenomenon of milk intolerance and simply leaves out all dairy products. This improves her symptoms to a certain degree.
Now she develops a profound interest in the subject and realises that lactose, the carbohydrate in milk, is not only contained in dairy but also in a lot of convenience food and even some medication. After that she also eliminates these products from her diet and her symptoms disappear completely.

Lactose  and Lactase
People with lactose intolerance either cannot digest lactose (milk sugar) from food sources properly or not at all. This is caused by a lack of the enzyme lactase.

Lactose is a disaccharide, which is composed of the monosaccharides galactose and glucose.
Lactose represents the most important carbohydrate in the milk of mammals and the respective concentration depends on the species. 

Species Lactose concentration
Human milk 7,0 %
Horses milk 6,2 %
Cows milk 4,8 %
Goats milk 4,4 %
Sheeps milk 4,2 %
       Table 1: Lactose concentration in milk of different species

 Lactose is of crucial importance in nutrition and especially for babies.
It is the most important energy source during the first years of a baby’s life.
It makes sure that the physiological gut flora can develop and that the calcium in milk can be best utilised by the body.
In the food industry lactose also plays an important role. Due to its chemical and technological properties lactose is frequently used in the production of industrial food products like baked products, sweets, meat preparations like pates, low fat foods, convenience foods, spice mixtures and artificial sweeteners. Lactose works as a binder and a carrier for aroma substances. It ensures a better firmness and a higher volume.
A lot of medication also contains lactose as a filler or for taste correction.

To enable absorption by the body the disaccharide has to be split into its two monosaccharides. Lactase is the necessary enzyme, which can split the ß-glycosidic bond between galactose and glucose.

Frequency and Prevalence
A lack of lactase is the world’s most frequent ‘enzyme deficiency’.
About two thirds of the world’s human population loose the ability to split lactose after weaning – as do most mammals. Interestingly there is a characteristic North-South gradient.
In Scandinavia only 3-8% of the population show a loss of lactase after weaning. In Germany about 13-14% and in Austria about 20% of the population is lactose intolerant.
However, this number is on the increase through the rising number of immigrants from the Mediterranean.
In the Mediterranean the percentage of the population with lactose intolerance is rising to about 70%, and in Africa close to the equator about 98% of the population show lactose mal-digestion.
It is assumed that the distribution of lactose intolerance has a connection to sunshine.
In Northern countries the population has to manage on much less sunshine than the population near the equator. The human organism needs UV-rays for the production of vitamin D, which is needed for the efficient absorption of calcium from food.
With their ability to digest lactose, which also promotes calcium absorption, people in countries with less sunshine could prevent calcium deficiencies.

A long time ago a coincidental mutation, which is responsible for permanent lactase production, must have been successful in light-skinned Northern Europeans and Americans. This created the tolerance of milk and milk products and later enabled the development of the milk industry.

Please note:
In about 75% of lactose intolerant people fructose intolerance can also be found.
Please ask the laboratory for more information.

Forms of Lactose Intolerance
In lactose intolerance we generally distinguish between two forms.

1. Primary lactase deficiency
This is the most frequent form of lactase deficiency. It is hereditary.
Whilst in our countries lactase intolerance usually only occurs at adult age, in a great number of the world’s population the decline of lactase activity even happens in infants.
Older people practically always have lactose intolerance.
Primary lactase deficiency most frequently occurs in South-East Asia, Central Africa and in the Mediterranean.
A very rare form of primary lactase deficiency is Congenital Lactase Deficiency (CLD).
In this autosomal recessive hereditary disease lactase activity is lacking even directly after birth. Because mother’s milk contains a lot of lactose these babies suffer from severe watery diarrhoea, dehydration and malnourishment. A strictly lactose free diet has to be maintained because even the smallest quantities of lactose can cause severe development damage for newborn babies.

2. Secondary lactase deficiency
Secondary forms of lactase intolerance can occur when the surface of the small intestinal epithelium is damaged by disease. The cause of the damage is insignificant. As soon as the absorption surface is diminished a functional limitation of lactase activity follows because the enzyme occurs in the microvilli.

The following diseases can lead to a loss of lactase activity:
1. Bacterial dysbiosis in the small intestine, overgrowth syndrome
2. Celiac disease
3. Radiation induced enteritis (radiation in tumour therapy)
4. Infectious enteritis and infectious diseases
5. Reduced contact times with accelerated intestinal passage

What is the Cause of the Symptoms in Lactose Intolerance?
Lactase splits lactose into its two components, galactose and glucose. These two monosaccharides are absorbed in the small intestine. In contrast, unsplit lactose remains in the intestine. This lactose reaches lower intestinal areas and is then fermented by gut bacteria. The fermentation products methane, carbon dioxide and short chain fatty acids, which leads to symptoms like gas, wind and osmotic diarrhoea. In addition to that the gut bacteria can produce a number of biologically active substances. This is the reason for symptoms of lactose intolerance not limited to the GI tract.

 

Original substance Biogenous amine Effects
Histidine Histamine Pseudo allergy, cluster migraine, colic, flush, neuro transmitter
Phenylalanine Phenylethylamine Headache, vertigo, nausea
Tyrosine Tyramine Indirect sympatho mimetics, increase in blood pressure,  palpitations, head ache
Dihydroxyphenylserine Noradrenaline increase in blood pressure,   anti-cholinerge and anti-serotoninerge properties, feeling cold
Ornithine Putrescine Growth factor for bacteria and moulds,  increases  histamine toxicity
Table 2: Biogenous amines, which can develop in the intestine

(Table from Ledochowski, M. et. al., 2003, J. Ernährungsmed, Laktoseintoleranz)

Symptoms of Lactose Intolerance
diarrhoea/diarrhoea like problems
(These problems can occur as early as 15-30 minutes after the lactose containing meal,
a few hours later or even in the morning of the following day.)

mushy stool      tummy rumbling
bloating      vomiting
constipation       wind
feeling sick after food     tummy ache
belching      colic like pain

Non-specific complaints
chronic tiredness     joint pain
depressive moods     restlessness
subjective feeling ill     nausea
headache      exhaustion
nervousness      feeling low
feeling tense      sleep problems
skin impurities     lack of concentration
deficiency symptoms     fatigue

(from Schleip, Laktoseintoleranz, Trias-Verlag)

 
Diagnostics
In former times lactose intolerance was diagnosed by a lactose tolerance test.
Before and after a provocation meal of 50g lactose (in children 2 g/kg, maximum of 50g)
blood was taken to measure blood glucose. If there was an increase of blood glucose of over 20 mg/dl in two hours, it was assumed that sufficient lactose had been split and absorbed.

 

 

Today this lactose intolerance test has been widely replaced by the H2 breath test in which the
hydrogen concentration is measured before and after a provocation meal with 25g lactose (in children  1g/kg, maximum 25g).
If there is an increase in H2 concentration by more than 20 ppm above the basal reading, it can be assumed that enough lactose has been metabolised.

Both methods can lead to severe symptoms in lactose intolerant patients.

A gene test is a new detection method. Only recently the genetic cause for the lactose intolerance was discovered. At the location 13910 before the lactase gene (LCT) there is a polymorphism, which determines the quantity of lactase produced. By testing the LCT genotype the genetic disposition can be determined.
LCT-Genotype Importance
LCT-13910 TT No genetic lactose intolerance (approx. 40 % of the population)
LCT-13910 TC: Heterozygote symptom carrier, no increased risk of a primary lactose intolerance  (approx. 45 % of the population)
LCT-13910 CC: Genetic disposition for lactose intolerance (approx. 15 % of the population)

      Table 3: LCT-Polymorphisms in the population

The gene test is performed from a simple swab of the mouth mucosa inside the cheek.
Epithelial cells stick to the cotton bud. The investigation is done on their cell nuclei. If you are interested in this test, please send us an email. We do not have this test on our automatic buying options, but we can bill you via Paypal and send you the test kit. Price 85.00 GBP.

Therapy
Because milk and milk products can cause the problems described, diet recommendations have so far concentrated on avoiding or reducing milk, milk products and foods containing lactose.

The following foods are free of lactose

 meat     fish
 fruit and veg    potatoes, pasta, rice
 pulses     grains
 mineral water, fruit juices  tea, coffee
 plant oils    eggs

Until recently it was difficult for the consumer to find out which foods contained added lactose.
A declaration of lactose as a carrier substance for aromatic substances or as an emulsifier in processed foods was not regulated by law.  However, on the 25th November 2005 the EU rule 2003/89/EG was put into force. According to this lactose has to be declared in the ingredient list. 
Numerous milk and milk substitute products are commercially available which are mostly based on soya or rice. Some manufacturers also offer lactose free milk and milk products.
One problem, which can occur in lactose-intolerant people, is calcium deficiency since milk and milk products are the best sources of the mineral calcium in human diet.
Calcium has, for example, important properties in the stabilisation of cell membranes, the transmission of nerve signals and in blood clotting. It is also very important for the stability of bones and teeth. Because lactose intolerant people have a lower supply with milk and milk products, there is the danger of acquiring osteoporosis.
Generally the demand for calcium can also be met with plant food like kale, spinach, broccoli
and soya beans. However, calcium from these sources is not as readily available for the human organism because of the oxalic acid content. It might be wise to supplement calcium in combination with vitamin D3, which supports the absorption of calcium. 
To prevent symptoms and for a better tolerance of products containing lactose the enzyme lactase can be supplemented in tablet or capsule form. It should be taken before meals.
Each patient has to find out their own individually-appropriate dose. With a lactase supplement eating out, when the patient has no influence on the ingredients, is much easier for sufferers.
In the UK lactase supplements are available for example from Solgar: Lactase 3500;
or from BioCare: Lactase Enzyme.
It can also be beneficial to add Okoubaka, a very useful homeopathic remedy to counteract the typical symptoms of food intolerance.

Lactobacilli can also make a valuable contribution. They produce lactase, the enzyme which is lacking in the gut of lactose intolerant people. Please make sure that the lactobacilli supplement of your choice has been produced lactose free. These lactobacilli should also be resistant enough to survive the stomach passage.

References
– M. Ledochowski, Bair, H., Fuchs, D., Laktoseintoleranz, J. Ernährungsmed., 2003, 5 (1) 
  Ausgabe für Österreich, 7 – 14.
– Sonntag, S., Phänomen „Laktoseintoleranz – Laktasemangel“, OM & Ernährung, 2006. Nr.
  115, S. 14 – 17.
– Stuparsky, A., Milchzuckerunverträglichkeit Laktoseintoleranz, Umwelt & Gesundheit,
  2003 (3), 104 – 108.
– Schleip,T. Laktoseintoleranz, Trias-Verlag, 2004.

Author:
Christiane Pies, MSc
Head of Science
Dr. Hauss Laboratory
Kieler Str. 71
24340 Eckernförde
043 51- 71 26 81

SAMPLE REQUIREMENTS:    
The gene test is performed from one simple swab of the mouth mucosa inside the cheek.
Epithelial cells stick to the cotton bud. The investigation is done on their cell nuclei.