Updated on April 7, 2023
Addressing autism is challenging owing to the disease’s diverse symptoms, uncertain causes, and disabling effects. Autistic individuals are commonly affected by a broad array of sensory issues, sociobehavioral difficulties, and gastrointestinal malfunction, all of which can severely diminish quality of life. Although some therapies are helpful, patients often still struggle to reach neurotypical levels of daily functioning. The lack of curative therapies for autism often drives caregivers and the autistic individual to experiment with a plethora of less than satisfactory effective therapies. For a growing number of families, one of those therapies is probiotics.
Probiotics are living bacterial cultures that are intended for oral consumption to confer a number of health benefits. Historically, probiotics have been attributed to long lifespans and good health in certain rural communities with diets that emphasize pickled foods; pickled foods like sauerkraut and kimchi are rich in the same beneficial microbiota that modern probiotic supplements are made from.
In current times, probiotics are being investigated as an autism-targeted therapy that could address behavioral and gastrointestinal symptoms by altering the gut microbiome. The rationale behind using probiotics to address autism symptoms is that rectifying the dysfunctional microbiomes of autistic individuals might modulate complex autistic symptoms via the gut-brain axis. Although it is unknown whether this rationale is clinically sound, it is rapidly gaining popularity within the scientific community, and researchers are currently working to gain greater clarity into the potential of gut microbiome manipulation.
At present, the U.S. Food and Drug Administration has not approved any probiotic supplement to treat any disease. Nonetheless, many autism patients use probiotics due to their purported benefits. To determine if this is the most appropriate approach, it’s critical for caregivers of autistic individuals to understand the potential side effects of probiotics and consider whether there might be superior alternatives.
Recent reviews of probiotic side effects conclude that most individuals, autistic or not, tolerate probiotics extremely well. Mild and transient gastrointestinal disturbances, like nausea, bloating, gas, or diarrhea, can occur but are uncommon and appear to be innocuous. Likewise, these side effects typically are not persistent if a person experiences them at some point. In autistic individuals, however, there might be a greater chance of experiencing these side effects. This is because autistic individuals tend to experience gastrointestinal abnormalities at a higher rate than other people because of genetic and microbiotal factors, so caution is warranted before starting a probiotic therapy course that could aggravate an aggrieved stomach.
According to some reports, there might also be behavioral consequences to probiotic therapy. Anecdotal evidence suggests that autistic individuals are at a risk of experiencing insomnia and aggression resulting from probiotic supplementation. Likewise, sparse and anecdotal reports document behavioral regression after supplementation with probiotics. However, these behavioral side effects appear to be rare, and the gastrointestinal side effects tend to recede with repeated exposure. Gradually phasing in increasing quantities of probiotics might also help to avoid side effects.
Due to the mild nature of the scientifically confirmed side effects of probiotics, many individuals experiment with probiotics on their own without concern. In the overwhelming majority of cases, the biggest risk involved in using a probiotic supplement is that it might not taste very good. To solve this, commercial probiotic products can be easily mixed into other foods or administered as a flavored liquid formulation, making probiotic use more appealing. In the event of food refusal, there are also several probiotics that can be administered enterally, although it is not the preferred route.
The vast majority of individuals do not experience any side effects from using probiotics, whether or not they have autism. There are, however, conditions under which consuming probiotics can have serious side effects. Individuals who are immunocompromised, catheterized, or recovering from invasive surgery, for example, might want to avoid probiotics. The side effects of probiotics for these individuals can range from extreme inflammatory reactions to sepsis, both of which can be life-threatening conditions.
There is some evidence to suggest that individuals in a medically compromised state are at risk of developing complications if they consume probiotics. One study, for example, found that patients who were administered probiotics while experiencing acute pancreatitis were 10 percent more likely to die than those who were administered a placebo. However, this study had no reference to the mechanism by which the probiotics might have caused the increased mortality. Additionally, the evidence regarding probiotic side effects in severe cases is somewhat ambiguous; several pieces of literature claim that probiotics are associated with improved outcomes in the immunocompromised or recovering patient populations, whereas several others have documented the negative side effects. The medical consensus on administering probiotics to weakened patients is still forming, and firm conclusions are impossible to make. As such, practitioners and their patients should proceed with caution. In the case of catheterized patients, probiotics might increase the risk of infection, and other invasive medical devices like insulin pumps and colostomy bags likely carry the same risks. Out of an abundance of caution, patients in these conditions might want to avoid taking probiotics.
There is no evidence to suggest that autistic individuals are at a higher or lower risk of experiencing negative side effects than others either while healthy or in a weakened state. However, an autism patient who is taking a probiotic supplement might need to reconsider their probiotic use should they fall into one of the potential risk groups above.
As discussed, the typical side effect profile of probiotics is very mild, and the more serious side effects appear to be confined to very narrow niches, suggesting that probiotics are generally safe and well-tolerated. But it is important to realize that a comprehensive scientific consensus on probiotic side effects remains elusive.
Several side effects of probiotics are theorized to exist but are not yet confirmed, including runaway immune activation, maladaptive bacterial gene transfer, and lactic acidosis. The implications of these phenomena vary widely; runaway immune activation could potentially be fatal, whereas lactic acidosis would merely be uncomfortable. However, as autistic individuals tend to have sensory integration issues that make being overstimulated extremely unpleasant, lactic acidosis can have a particularly significant impact. Meanwhile, researchers have minimal understanding of what problems patients would face in the event of widespread maladaptive bacterial gene transfer, given that no mechanism has been proposed nor instances of it observed.
It’s valuable to remember that even if these side effects are confirmed to occur only in certain conditions, probiotic supplementation would still remain very safe for the vast majority. At present, there is no evidence to suggest runaway immune activation or bacterial gene transfer has genuinely occurred in any individuals or group consuming probiotics. There are, however, a small number of reports on individual patients with short bowel syndrome who experienced lactic acidosis as a result of probiotic consumption. Although the patients experienced an array of neurological symptoms ranging from agitation to confusion, all improved immediately on cessation of probiotic use. These results will need to be validated in larger clinical trials before clinical advisories against using probiotics can be made with confidence. Other therapeutic options with a similar level of evidentiary backing could be more suitable for patients in the meantime.
For individuals who prefer an alternative to probiotics—whether due to efficacy concerns, tolerability, or potential side effects—butyric acid is a good place to begin. Butyric acid is a short-chain fatty acid produced by the gut and is responsible for regulating the gastrointestinal tract and the immune system, which could have significant implications for behavioral health due to the activities of the gut-brain axis.* Notably, this vital fatty acid has been shown to be deficient in autistic individuals, potentially contributing to autism presentation, including both gastrointestinal and behavioral symptoms. By maintaining a healthy level of butyric acid and supporting the health of the gut microbiome via oral supplementation, it could be possible to beneficially impact these symptoms and enhance overall quality of life.*
Unlike probiotics, butyric acid’s side effect profile is not linked to an increased risk of infection or serious complications in immunocompromised individuals. Anyone with an abnormal intestinal length should consult with their doctor before trying butyric acid, however. For most people, supplementation with butyric acid is likely to have fewer and milder side effects than probiotics, while delivering comparable or superior benefits via the gut-brain axis.
This scenario might change depending on the latest research in probiotics, however; a large clinical trial investigating probiotic therapies for autism is underway. The results of this study will be among the most detailed yet published and will describe the physiological and behavioral changes attributable to several popular probiotic supplements. Side effects will be documented alongside the physiological states which the probiotics caused to generate those effects. Caregivers might want to follow up on the trial to see whether probiotic supplementation is definitively linked to side effects that are specific to its use in autistic individuals.
In the meantime, patients, caregivers, and practitioners evaluating probiotics or butyric should be emboldened by their benign side effect profiles and potential to improve the lives of autistic individuals. When integrated into a comprehensive management plan, these supplements could play a valuable role in providing nutritional support for addressing symptoms, bringing relief and comfort to patients and their families.*
The power of Tesseract supplements lies in enhancing palatability, maximizing bioavailability and absorption, and micro-dosing of multiple nutrients in a single, highly effective capsule. Visit our website for more information about how Tesseract’s products can help support your gastrointestinal health.*
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