[Lactose intolerance: past and present. Part II]. / A laktózintoleranciáról: Múlt és jelen - II. rész.

The author summarises the interrelations between lactose intolerance, calcium and vitamin D metabolism and osteoporosis. Lactose intolerance enhances the risk of forearm and hip fractures in some patients. Lactase gene genotype and fracture risk are related in some populations. Calcium and vitamin D supplementation increase bone mineral content and they are justified in children, during pregnancy and lactation, and in postmenopausal women. The intake of milk and milk products could increase the risk of ovarian carcinoma. CC genotype of the lactase gene increased the risk of colorectal carcinoma in Finns; no such effect was observed in British, Spanish and Italian patients. Even small quantities of lactose in drugs (10-750 mg) could elicit intolerance symptoms due to individual susceptibility. In spite of public knowledge and advertising, controlled studies did not prove the beneficial effect of either a lactose-free diet, enzyme supplementation or probiotics in an evidence-based manner. While accepted guidelines are lacking, a personalised therapy is mandatory. In spite of increasing public interest in lactose intolerance, many unknown factors must still be studied.

Lactantes menores alimentados con fórmula de soya: evaluación de hormonas tiroideas / Infants fed with soy formula: evaluation of thyroid hormones

La alimentación a base de soya, se ha relacionado con alteración de la función tiroidea, debido a la presencia de fitoestrógenos en su composición. Es por ello, que el presente estudio tiene como objetivo determinar la función tiroidea en lactantes menores de 6 meses alimentados con fórmula infantil a base de soya. Es un estudio descriptivo, transversal. Se evaluaron 28 lactantes que recibieron fórmula infantil de soya, como única alimentación. Variables utilizadas: edad, sexo, Graffar-Méndez Castellano, motivo de indicación de la fórmula, dilución, onzas diarias ingeridas, determinación de T3-libre y T4-libre y TSH sérico. Para el análisis estadístico se aplicó t de Student para un nivel de significación estadística de p<0,05. Los valores séricos de T3 y T4 libres se mantuvieron dentro de rangos normales. 7% de la muestra mostró valores elevados de TSH, no siendo estadísticamente significativo. No existió relación estadística entre el consumo de fórmula de soya y función tiroidea. Sin embargo, en la muestra estudiadados de los pacientes presentaron aumento de los niveles de TSH, por lo que no se puede descartar la posibilidad de una asociación dado lo limitado de la muestra.

Feeding with soy has been related to alteration of thyroid function. The objective of this study was to determine thyroid functionalism in babies under 6 months of age fed with infantile soy based formula. Descriptive, cross-sectional, non experimental study. Twenty eight babies who received exclusively infantile soy based formula were evaluated. Variables studied were: age, gender, socio-economical level, reason for the prescription of soy formula, dilution, daily ounces, determination of free T3, T4 and TSH. For the statistic analysis, Student’s t test was applied for a statistical significance level of p<0.05. Serum free T3 and T4 were within normal ranges. 7% of the sample showed elevated levels of TSH, with no statistic significance. there was no statistical relationship between consumption of soy formula and thyroid function. However, two patients had increased levels of TSH and therefore, the possibility of an association cannot be ruled out given the small size of the sample.

Digestive and nutritional considerations in celiac disease: could supplementation help?

Due to the increased immune activation in the intestinal tract of people with celiac disease, the digestive and absorptive processes of those affected may be compromised. Individuals with celiac disease are more susceptible to pancreatic insufficiencies, dysbiosis, lactase insufficiencies, and folic acid, vitamin B12, iron, and vitamin D deficiencies, as well as accelerated bone loss due to an increase in inflammatory signaling molecules. Beyond strict maintenance of a gluten-free diet, research has shown benefit with additional nutritional supplementation to assist in regulation of several of these complications.

Lactose intolerance: a non-allergic disorder often managed by allergologists.

Lactose malabsorption is a very common condition characterized by intestinal lactase deficiency. Primary lactose malabsorption is an inherited deficit present in the majority of the world's population, while secondary bypolactasia can be the consequence of an intestinal disease. The presence of malabsorbed lactose in the colonic lumen may cause gastrointestinal symptoms. This condition is known as lactose intolerance. Lactase non-persistence is the ancestral state, whilst two single nucleotide polymorphisms in the lactase gene have been associated with lactase persistence. These are C/T 13910 and G/A 22018 substitutions. Lactase persistence, this Mendelian dominant trait, only became advantageous after the invention of agriculture, when milk from domesticated animals became available for adults to drink. Lactase persistence is then strongly correlated with the diary history of the population. Diagnosis is assessed clinically by elimination of dietary lactose or, better, by non-invasive tests including hydrogen breath test and genetic test. In patients with lactase non-persistence, treatment should be considered exclusively if intolerance symptoms are present. In the absence of guidelines, the common therapeutic approach tends to exclude milk and dairy products from the diet. However, this strategy may have serious nutritional disadvantages. Several studies have been carried out to find alternative approaches, such as exogenous beta-galactosidase, yogurt and probiotics for their bacterial lactase activity, strategies that can prolong contact time between enzyme and substrate delaying gastrointestinal transit time, and chronic lactose ingestion to enhance colonic adaptation.

Lactose maldigestion is not an impediment to the intake of 1500 mg calcium daily as dairy products.

BACKGROUND: A National Institutes of Health consensus conference concluded that a daily calcium intake of 1500 mg reduces the severity of osteoporosis. Because dairy products are the main natural source of dietary calcium, a diet providing 1500 mg Ca must contain large quantities of dairy products. However, it is widely believed that the lactose content of these products will not be tolerated by persons with lactose maldigestion (approximately 30% of the adult US population). OBJECTIVE: We evaluated the symptoms of lactose maldigestion and digestion when the diet was supplemented with dairy products providing 1300 mg Ca/d. DESIGN: Sixty-two women (31 with lactose maldigestion and 31 without) were studied in a double-blind, randomized protocol. Symptoms were compared during 1-wk periods when the diet was supplemented with 480 mL (2 cups) milk, 56 g cheese, and 240 mL yogurt provided as conventional products (34 g lactose/d) or as lactose-hydrolyzed products (2 g lactose/d). RESULTS: Women who digested lactose reported no significant difference in symptoms between the 2 treatment periods. Women with lactose maldigestion reported significantly increased flatus frequency and subjective impression of rectal gas during the period of high lactose intake; however, bloating, abdominal pain, diarrhea, and the global perception of overall symptom severity were not significantly different between the 2 treatment periods. CONCLUSION: The symptoms resulting from lactose maldigestion are not a major impediment to the ingestion of a dairy-rich diet supplying approximately 1500 mg Ca/d.

Nutrition during pregnancy.

Nutrition assessment and counseling are integral components of preconception and prenatal care. The average-size woman should gain between 11.25 and 15.75 kg (25 and 35 lb) during a normal pregnancy. Some factors identify the pregnant woman with a nutrition risk. Vitamin and mineral supplementation should be based on a dietary assessment. Common discomforts of pregnancy frequently can be managed with dietary modification and safe pharmacotherapeutics. The coordinated efforts of health care providers, registered dietitians, the Women, Infants, and Children (WIC) nutrition program, local health departments and Cooperative Extension Service offices can provide appropriate nutrition assessment, education and intervention.

Temproary intestinal lactase deficiency in light-treated jaundiced infants.

The intestinal lactase activity in six newborn jaundiced light-treated infants with diarrhea and in eight normal controls were compared by lactose tolerance test (LTT). The ability to hydrolyze lactose was minimal in the jaundiced infants during light-treatment compared to the controls which could absorb lactose very well. Peroral intestinal biopsies were taken from the newborn jaundiced infants during light-treatment. By histochemical technique no intestinal lactase activity was found in these intestines. When the jaundiced infants with diarrhea were given lactose-free diet, the stools normalized. The effect was reversed when breast milk was given while the baby was still jaundiced and light-treated. These findings indicate that the increased amounts of unconjugated bilirubin in the intestine of jaundiced infants during light-treatment inhibit the intestinal brush-border lactase. When the icterus fades the lactase is again active. The practical consequence is to give light-treated infants lactose-free diet if they get diarrhea, and to reintroduce breast milk or other lactose containing diet when the baby is no longer icteric.