AUTHOR: Dr. Jason Bush
Short Chain Fatty Acids (SFCAs) are the by-products of prebiotic metabolism that are left over after they have been fermented by probiotic bacteria. However, these molecules exert a range of important effects that significantly contribute to our gut health. Here are three important take-aways to help you understand the relationship between increasing prebiotics in your diet and some of the related health benefits:
Harmful bacteria do not thrive under acidic conditions
SCFAs are acids – meaning that they lower the pH of the environment. In the case of gut health, that environment is the large intestine. This is important because many harmful bacteria, including pathogenic forms of E. coli, cannot tolerate an acidic environment and therefore their growth will be inhibited when SCFA production is high. An important note: Don’t be scared by the term ‘acid’ in Short Chain Fatty Acid – these molecules are not strongly acidic like stomach acid and will not harm the lining of your digestive tract.
Your microbiome needs to speak to you
SCFAs have the incredible ability to transmit information from the bacteria in your gut microbiome to the human cells of your body. Butyrate, a type of SCFA, communicates a variety of messages. As I wrote previously, butyrate from prebiotic fermentation can actually help suppress appetite, helping to explain why dietary fiber contributes to a sense of fullness after meals. In addition to other important signaling cascades, SCFAs also signal to hormone-producing cells in the large intestine to improve blood sugar regulation.
A natural source of sugar-free energy
Most cells in our body burn glucose, a type of sugar, in an oxygen-rich system to provide them with the energy they need to function. The cells lining the large intestine are different. These cells exist in an oxygen-poor environment and have adapted by utilizing molecules other than glucose to supply them with energy. Butyrate is a prime source of energy for colonocytes and some estimates suggest that SCFAs normally supply approximately 10% of the body’s total energy requirements.
Hopefully this helps highlight some of the benefits of prebiotic fermentation in the large intestine and the importance of SCFAs. Can you take SCFA supplements? Sure, but it’s likely that oral SCFA supplements will be absorbed early in the digestive tract, away from where they are most effective. Prebiotics make sure that the SCFAs are produced where the body really needs them.