News article

Persistent Gut Microbiota Immaturity In Malnourished Bangladeshi Children

Posted:  Monday, July 07, 2014

Health experts say Bangladesh has one of the highest rates of child malnutrition in the world. Millions of children suffer from one or more forms of malnutrition, including low birth weight, stunting, underweight, Vitamin A deficiency, iodine deficiency disorders and anemia.

Malnutrition contributes to about half of all child deaths, often by weakening immunity. Survivors are left vulnerable to illness, stunted or intellectually impaired.

Newborn deaths make up nearly half of all under-five deaths (57 percent) and 71 percent of infant mortality. One neonate dies in Bangladesh every three to four minutes; 120,000 neonates die every year, according to UNICEF.

Malnutrition among women is also extremely prevalent in Bangladesh. More than 50 percent of women suffer from chronic energy deficiency and studies suggest that there has been little improvement in women's nutritional status over the past 20 years.

Malnutrition passes from one generation to next because malnourished mothers give birth to malnourished infants. If they are girls, these children often become malnourished mothers themselves, and the vicious cycle continues.

For those who survive beyond their fifth birthday, chronic malnutrition can have long-lasting effects and prevent children from achieving their potential in life: it is estimated that malnourished children earn 20% less in adulthood.

In recent years, scientists have come to learn that severe childhood malnutrition is not due to a lack of food alone. Rather, the condition is far more complex and may involve other factors including a breakdown in the way gut microbes process various components of the diet.

Faecal samples were obtained from the children before they received the therapeutic foods and every three days while they were being treated for malnutrition. Most children received the therapeutic foods for about two weeks, until they had reached certain weight milestones, as is the standard of care. After treatment ended, the children were followed for four months, and faecal samples were collected monthly.

All the children gained weight on the therapeutic foods, and no significant difference existed in the rate of weight gain based on the type of food a child received. But the therapeutic foods only had a transient improvement on the maturity of a child’s gut microbe community. Once the therapeutic food was discontinued, the gut microbe communities regressed to a more immature state.

Researchers said: "Although therapeutic food-based interventions have resulted in a significant decline in deaths from malnutrition, many children never fully recover.

"We found that children who were malnourished had gut microbial communities that were not consistent with their chronological ages.

"Moreover, the severity of a child's malnourishment was tied closely with the degree of immaturity of his or her gut microbial community, and this immaturity could not be durably repaired with standard treatments."

The authors suggest children may fare better if they are given nutritional supplements for longer, or if they are given additional gut microbes.

The study focused on severely malnourished children, which further emphasises the importance of a mature diverse gut microbiota in human health.

"The findings were novel, unexpected and compelling, and show that purely nutritionally based interventions do not fully restore a mature gut microbiota in these children.