Since the 1980s, the recommendations for when to introduce gluten to children have changed four times – and scientists still disagree on how to prevent gluten intolerance among small children. The unreliable dietary advice for babies appear to be the result of scientific carelessness. Scientists have neglected to test the hypothesis using well-conducted and controlled studies.
The Swedish newspaper SvD recently published a number of articles about dietary guidelines, written by medical journalist Gunilla Eldh and myself. Last Friday, they printed our articles about dietary guidelines for small children. The first one was about Celiac disease, and the advice to introduce gluten to babies before six months. For some children, if worst comes to worst, this may actually have triggered the development of Celiac disease. The second article was about the advice to delay the introduction of allergenic foods to children at high risk of allergy. Current advice is moving away from delaying the introduction of potential allergens, but it is still possible that previous advice contributed to the development of allergies in children.
All dietary guidelines must be scientifically valid
In one of the first articles published by Swedish Svd, some scientists claimed it is difficult to assess the effects of dietary advice using so called randomized controlled trials (RCTs), the form of study that evaluate results and side-effects. According to many scientists, the participants don’t follow the advice they are given, they quit, also, randomized controlled trials are expensive to conduct. This is how they justify the fact that so many dietary guidelines lack scientific credibility.
When it comes to dietary advice for small children, none of these excuses will work. Already back in the 1990s, when these guidelines were introduced, it would have been fairly easy to test the hypothesis that early exposure to gluten may help babies avoid Celiac disease. Scientists could have divided a couple of hundred babies into two groups, and introduced only one of them to gluten. Instead, we had to wait almost 20 years before some other scientists proved the guidelines wrong. If worst comes to worst, the advice to introduce gluten to babies before six months may have triggered the development of Celiac disease.
The same goes for food allergies. In the beginning of the 1990s, specialists issued warnings about allergenic foods, saying that parents should delay the introduction of allergenic foods to children at high risk of allergy. Today – 20 years later – well-conducted scientific studies show that
early introduction to allergenic foods like peanuts, fish and egg, might actually be key to preventing kids’ allergies. Previous advice has probably contributed to the development of allergies in children.
Scientific carelessness can lead to mistakes
Unfortunately, the Swedish National Food Administration won’t learn from mistakes. Once again, we have new recommendations on gluten introduction to prevent Celiac disease. According to the new guidelines, parents should introduce gluten slowly and step-by-step. However, once again, they fail to inform us about the scientific evidence for this advice.
Yet another example of scientific carelessness. Scientists claim they know what they are talking about, even when they have no clue.
In our bodies, there’s a machinery of molecules, developed by millions of years of evolution. Step-by-step, we begin to grasp how this enormous machine works, but there is still so much more to learn. I think it’s time to be a bit more humble and admit that we don’t know everything. Nevertheless, we have invented an incredibly powerful instrument to help us learn more about the world around us: the scientific method. When scientists follow the rules of the scientific method they tend to discover extraordinary things; when they fail to follow the rules, they make mistakes.
When it comes to dietary guidelines for babies, it’s incredibly important that the scientists do their job. Both Celiac disease and food allergy will affect the wellbeing of the child. No one should suffer because of someone else’s carelessness.
Science journalist and writer Ann Fernholm runs the blog annfernholm.se. Now and then, she writes here at Food Pharmacy.