The Pros and Cons of Synbiotic Dietary Supplements
Last updated: 10th January, 2025
Synbiotic supplements, combining prebiotics and probiotics, have become a promising way to improve gut health. They come in two types: complementary and synergistic, with most products being complementary due to formulation challenges. This article explores the benefits of synbiotics and the challenges in their development.
What are Synbiotic Dietary Supplements?
The International Scientific Association for Probiotics and Prebiotics (ISAPP) defines synbiotics as “a mixture comprising live microorganisms and substrate(s) selectively utilized by host microorganisms that confers a health benefit on the host.” (1).
Synbiotic products are categorized into two types: complementary and synergistic synbiotics.
- Complementary synbiotics: These are the most common type on the market. They include prebiotic and probiotic compounds that provide health benefits both together and independently. This means the pre- and probiotics do not need to interact with each other to be effective.
- Synergistic synbiotics: Unlike complementary types, synergistic synbiotics don’t always include traditional pre- or probiotic ingredients. Instead, they combine microorganisms and substrates that are specifically designed to work together, offering greater benefits than they would individually (2).
Understanding the differences between these types helps in choosing the right synbiotic supplement for optimal gut health.
What are the Benefits of Synbiotic Dietary Supplements?
Synbiotic supplements combine the benefits of prebiotics and probiotics, offering a range of potential health advantages, including:
- Improved gut health: Enhancing the balance of gut microbiota.
- Boosted immune function: Supporting the body’s natural defenses.
- Production of beneficial metabolites: Promoting the production of short-chain fatty acids, which are important for gut health.
- Reduced risk of metabolic conditions: Potentially lowering cardiovascular risk factors, insulin resistance markers, and the prevalence of metabolic syndrome (3).
Addressing the Responder/Non-Responder Phenomenon
One unique advantage of synbiotic formulations is their ability to overcome the responder/non-responder phenomenon (2). This occurs because individuals have unique gut microbiota compositions, meaning not everyone responds to pre- or probiotic products in the same way.
By providing both bacterial strains and their specific substrates simultaneously, synbiotics create an environment that supports the growth and colonization of beneficial bacteria. This dual approach acts as a “fertilizer,” allowing the introduced strains to outcompete existing gut bacteria and establish themselves.
This targeted mechanism increases the likelihood that users will experience the desired health benefits, making synbiotic supplements a promising option for personalized gut health solutions.
Challenges in formulating Synbiotic Dietary Supplements
- Formulating synergistic synbiotics poses several challenges:
- Prebiotic Dosage: High doses are needed for benefits but may cause bloating or flatulence. Lower doses risk reduced effectiveness.
- Microorganism Sensitivity: Probiotics are sensitive to environmental factors, complicating storage and shelf stability.
- Water Activity: High water activity in substrates increases contamination risk; low-water-activity substrates are preferred (4).
- Research Gaps: Many formulations prioritize cost and availability over functionality, with limited human trials showing consistent benefits.
- Costly Clinical Trials: In vitro models like TIM-1 and TIM-2 simulate gut conditions to test survival and efficacy, reducing reliance on expensive trials.
Addressing these issues is key to realizing the full potential of synbiotic supplements.
