Fiber is the most under-discussed macronutrient in mainstream nutrition. It gets collapsed into "good for digestion" and left there. The actual story is considerably more specific, and interesting.
A single serving covers roughly 55–85% of the daily recommended intake depending on age and sex. But the number is only part of it. What the fiber does depends almost entirely on what kind it is and where it comes from.
Two types of fiber, two different jobs
Fiber is not a single thing. It divides into two broad categories with distinct functions.
Insoluble fiber doesn't dissolve in water. It adds bulk to stool, speeds transit through the colon, and reduces constipation. Most people associate fiber with this function.
Soluble fiber dissolves in water and forms a gel in the digestive tract. That gel slows gastric emptying, blunts glucose absorption, and, crucially, reaches the colon largely intact where the gut microbiome can ferment it.
That fermentation is where the more significant health story sits.
What prebiotic fiber actually does
Prebiotics are a subset of soluble fiber. They're not digested by the human body. Instead, they travel to the colon and serve as fuel for specific strains of beneficial bacteria, primarily Bifidobacterium and Lactobacillus.
When these bacteria ferment prebiotic fiber, they produce short-chain fatty acids (SCFAs): primarily butyrate, propionate, and acetate. These aren't waste products. They're signalling molecules with documented roles in gut function.
Butyrate is the primary energy source for colonocytes, the cells lining the colon. It provides approximately 70% of their total energy requirements [1]. It supports gut barrier integrity by regulating the assembly of tight junctions, which is what keeps gut contents inside the gut and out of systemic circulation [2].
Propionate travels to the liver and plays a role in glucose and lipid metabolism. Acetate enters systemic circulation and is used by muscle and other tissues.
A well-fed microbiome produces more of these. A fiber-poor diet starves the bacteria that make them.
FOS from chicory
The prebiotic fiber in Soma is fructooligosaccharides, sourced from chicory root.
Chicory is one of the most concentrated natural sources of inulin-type fructans, the category FOS belongs to. FOS are short-chain fructooligosaccharides: fermentable, not absorbed as glucose (so they contribute no glycemic load), and selectively fermented by Bifidobacterium and Lactobacillus strains over less beneficial bacteria.
The selectivity matters. Not all gut bacteria have the same effect on health. A systematic review of 50 human intervention studies confirmed that chicory-derived inulin-type fructans significantly increase the abundance of beneficial Bifidobacterium across all age groups [3].
Prebiotic fiber that specifically promotes this growth shifts the microbial balance toward strains associated with reduced inflammation, better immune function, and improved gut barrier integrity. This is what distinguishes FOS from chicory from generic "added fiber."
Beta-glucan from barley malt extract
Barley malt extract also contributes soluble fiber in the form of beta-glucan.
Beta-glucan is a viscous, gel-forming polysaccharide. In the gut, it slows transit, prolongs satiety, and is fermented by the microbiome into SCFAs. It has one of the most robust bodies of research behind it of any dietary fiber.
The European Food Safety Authority (EFSA) and the US FDA have both approved health claims for beta-glucan from oats and barley, specifically for its ability to lower blood cholesterol and reduce postprandial glycemic response [4].
Its inclusion via barley malt extract means the 21g fiber figure in Soma draws from two distinct soluble fiber sources with complementary mechanisms.
Where DigeZyme® fits
A formulation built around significant fiber intake requires the digestive system to be functioning well. DigeZyme® is a multi-enzyme complex covering amylase, protease, lipase, cellulase, and lactase. It supports the breakdown of carbohydrates, protein, fats, plant cell walls, and residual lactose before material reaches the colon.
This matters particularly in the context of a high-fiber, high-protein meal. Without adequate enzyme activity, incompletely digested protein and carbohydrate reaching the colon can cause gas and bloating.
A randomized, double-blind, placebo-controlled clinical trial demonstrated that DigeZyme® supplementation significantly reduces these symptoms, including bloating and abdominal pain, within 60 days [5]. This is especially relevant for anyone whose digestive enzyme activity is lower than optimal.
The 21g in context
The average urban Indian diet is estimated to deliver significantly below the 30g of daily fiber recommended by the ICMR-NIN [6]. A diet built around frequent restaurant and takeout meals, which tend to be low in vegetables, legumes, and whole grains, will generally land toward the lower end, with some urban populations averaging as low as 15–18g per day [7].
21g of fiber from a single serving, built from two soluble, prebiotic-rich sources, covers a meaningful share of what a day's diet typically misses.
References
1. Salvi, P. S., & Cowles, R. A. (2021). Butyrate and the intestinal epithelium: Modulation of proliferation and inflammation in homeostasis and disease. Cells, 10(7), 1775. https://doi.org/10.3390/cells10071775
2. Peng, L., Li, Z.-R., Green, R. S., Holzman, I. R., & Lin, J. (2009). Butyrate enhances the intestinal barrier by facilitating tight junction assembly via activation of AMP-activated protein kinase in Caco-2 cell monolayers. Journal of Nutrition, 139(9), 1619–1625. https://doi.org/10.3945/jn.109.104638
3. Nagy, D. U., Sándor-Bajusz, K. A., Bódy, B., Decsi, T., Van Harsselaar, J., Theis, S., & Lohner, S. (2022). Effect of chicory-derived inulin-type fructans on abundance of Bifidobacterium and on bowel function: A systematic review with meta-analyses. Critical Reviews in Food Science and Nutrition, 63(33), 12018–12035. https://doi.org/10.1080/10408398.2022.2098246
4. EFSA Panel on Dietetic Products, Nutrition and Allergies. (2011). Scientific opinion on the substantiation of health claims related to beta-glucans from oats and barley and maintenance of normal blood LDL-cholesterol concentrations, increase in satiety leading to a reduction in energy intake, reduction of post-prandial glycaemic responses, and "digestive function." EFSA Journal, 9(6), 2207. https://doi.org/10.2903/j.efsa.2011.2207
5. Majeed, M., Majeed, S., Nagabhushanam, K., Arumugam, S., Pande, A., Paschapur, M., & Ali, F. (2018). Evaluation of the safety and efficacy of a multienzyme complex in patients with functional dyspepsia: A randomized, double-blind, placebo-controlled study. Journal of Medicinal Food, 21(11), 1120–1128. https://doi.org/10.1089/jmf.2017.4172
6. Indian Council of Medical Research and National Institute of Nutrition. (2024). Dietary Guidelines for Indians. https://nin.res.in
7. Narayan, S., Lakshmipriya, N., Vaidya, R., Ramya Bai, M., Sudha, V., Krishnaswamy, K., Unnikrishnan, R., Anjana, R. M., & Mohan, V. (2014). Association of dietary fiber intake with serum total cholesterol and low density lipoprotein cholesterol levels in urban Asian-Indian adults with type 2 diabetes. Indian Journal of Endocrinology and Metabolism, 18(5), 624–630. https://doi.org/10.4103/2230-8210.139215