Short chain fatty acids are produced in the intestines through anaerobic fermentation of dietary fibers. SCFAs are the main source of energy for colonocytes. However, they have numerous other effects both in the intestines and throughout the body. Since SCFAs are produced through the consumption of dietary fiber, changes in diet are often the first step to increase levels. Compounding pharmacies are also now making customized formulations that include SCFAs for administration in enemas and suppositories.
SCFA Levels and Health
Measuring the SCFA levels in the intestines provides steady state levels but is not an accurate assessment of bacterial production. Most short chain fatty acids produced by the colon are absorbed through the gut mucosa. The SCFAs in fecal matter may be used as an approximation as the levels have been correlated to levels present in the gut. The majority of SCFAs are found in the intestine however small amounts are found in the blood, liver, and other parts of the body. This has lead to the hypothesis that they have some systemic effects outside of the digestive system.
What systemic effects exactly? Short chain fatty acids are a part of the gut-brain axis – they help reduce stress-induced cortisol release. They may be involved in regulation of appetite, in immune responses in the gut and peripherally, in the reduction of inflammation. Consuming dietary fiber has been associated with a reduced risk of developing cardiovascular disease, type 2 diabetes, and colon cancer. The consumption of dietary fiber leads to the increased production of short chain fatty acids.
Production of SCFA
SCFAs are primarily produced from the bacterial fermentation of undigested fibers. Most of them are absorbed in the gut but around 5% on average are excreted. This small amount that is excreted is the primary method of determining production levels in the intestines. The main SCFAs that are produced through this fermentation process are butyrate, propionate, and acetate. These three account for 95% of the short chain fatty acids produced. For cells in the colon, butyrate is the preferred energy source. Propionate produces glucose in the liver and small intestine and acetate is involved in energy production and synthesis of lipids.
Where in the intestines the production of SCFAs occurs and how many are produced is determined by the type of fiber, the gut transit time, and the type and quantity of microorganisms that are present in the intestines. Slowly digested fibers may shift production of SCFAs to the more distal colon. Gut transit time may affect how and where SCFA are produced or absorbed as well. A person’s diet and the drugs they take can affect gut transit time. Numerous factors are involved in determining how short chain fatty acids are produced.
Dietary Fiber and SCFA
Since dietary fiber is the main determination of SCFA levels, changes in diet are the first course of action. Due to their numerous health benefits, especially in managing chronic inflammatory conditions of the intestines, short chain fatty acids may be one treatment target for some conditions. Diets high in fiber include lots of fruits, vegetables, legumes. A low fiber diet has been associated with numerous health concerns related to depletion in gut microbiota. There is a subsequent increase in diseases like obesity, cardiovascular disease, and type 2 diabetes. A low fiber diet commonly found in Western countries is high in animal protein, fat, sugar, and starch. By changing the types of food a person eats, they may be able to increase short chain fatty acid levels and improve their health.
Supplementation of Short Chain Fatty Acids
A new method of increasing SCFA levels involves supplementation with enemas or suppositories. These drug dosage forms can be made to include a combination of butyrate, propionate, and acetate that is administered directly to the colon. The endogenous production of SCFAs involves the combination of gut bacteria and undigestable fiber. If the right amount and kind of bacteria are not present, there will be insufficient SCFA production. By supplementing through an enema or suppository, short chain fatty acid levels can be increased directly without a change in diet necessarily. Enemas and suppositories may be especially effective at treating inflammatory conditions of the colon.
Compounding Pharmacies
A compounding pharmacy can compound short chain fatty acid suppositories and enemas with butyrate, propionate, and acetate. This type of treatment is not yet available in a manufactured form and can only be compounded. Our pharmacy makes these suppositories and enemas with a combination of SCFAs that is similar to the actual ratio produced in the intestines. With a prescription, a patient can obtain this treatment and have it shipped directly to their home.