Probiotics have been gaining a reputation as a way to treat a wide variety of digestive upsets. Many of the studies to back up this recommendation have been small or not well done. Now, a careful placebo controlled trial in young children found that Lactobacillus rhamnosus GG was no better than placebo in halting gastroenteritis with diarrhea and vomiting (NEJM, Nov. 22, 2018).
Studying Probiotics for Gastroenteritis:
There were 943 children in the study. Half were younger than one and half years old. These children were brought to one of ten pediatric emergency departments. After doctors diagnosed them with gastroenteritis, they gave the young patients a five-day course of either the probiotic or the placebo.
The Results of the Study:
There was no difference in days missed from daycare, duration of symptoms or likelihood of spreading gastroenteritis to others in the household. A similar trial in Canada arrived at the same conclusion. Probiotics have been shown to be effective for other problems including C diff, but they don’t appear to offer any advantages for this common childhood illness.
Previous Research on Probiotics:
Probiotics for Blood Pressure:
Australian scientists analyzed nine randomized controlled trials and found that eating probiotic foods or products daily for at least two months lowered both systolic and diastolic blood pressure slightly (Hypertension, Oct. 2014). Study subjects who had blood pressure higher than 130/85 showed the strongest response to the intervention.
The lead author concluded
“…regular consumption of probiotics can be part of a healthy lifestyle to help reduce high blood pressure, as well as maintain healthy blood pressure levels.”
To be helpful, probiotic products needed a minimum of 10 billion colony forming units per dose. Foods rich in probiotics include yogurt with live cultures, aged cheeses or fermented vegetables such as kim chee or sauerkraut. There is also some evidence suggesting that diets rich in probiotic strains may help with cholesterol or blood sugar control.
Probiotics for Babies with Colic:
A few years ago, an Italian research team reports that colicky babies suffering from reflux or constipation benefit from probiotics (JAMA Pediatrics, March 2014). The investigators randomized more than 500 newborns to receive either a probiotic or a placebo. Parents kept track of diaper changes, vomiting, severe crying episodes and trips to the pediatrician.
The babies getting the probiotic experienced substantially less crying time, fewer throw-ups and more dirty diapers, suggesting less constipation. The authors conclude that adding Lactobacilli to the diet during the first few weeks of life may be beneficial for the digestive tracts of infants.
Probiotics for Eczema:
Young children frequently suffer from eczema. This skin condition, also known as atopic dermatitis, can cause redness, itching and significant discomfort. It is notoriously difficult to treat.
Dermatologists from the University of California Davis School of Medicine analyzed 21 studies examining probiotics and other dietary supplements for children from birth to three years old (Archives of Dermatology, March 2013). They found that children given the probiotic Lactobacillus rhamnosus GG were much less likely to develop eczema. Prebiotics together with black currant seed oil were also more helpful than placebo. The gamma-linolenic fatty acid in black currant seed oil was beneficial in reducing the severity of symptoms.