March 2026

Polysaccharides in herbal medicine

• Week 1: Polysaccharides in herbal medicine
• Week 2: Marshmallow – All The Juicy Details
• Week 3: Astragalus – Building A Whole Body Resilience
• Week 4: Reishi – The Mushroom Of Immortality

Polysaccharides in herbal medicine

What are polysaccharides?

As the name implies, polysaccharides are made of poly, meaning many (more than 10) saccharides, sugar molecules. Each sugar molecule (monosaccharide) is made out of one carbon atom, one oxygen atom, and two hydrogen atoms, hence the name carbohydrates or carbon combined with water(H2O).

Polysaccharides are made from long chains of sugar and are three dimensional complex structures.

Different types of polysaccharides provide different health benefits. The most common polysaccharides are:

• Starch
• Cellulose
• Inulin

Factors that affect polysaccharides’ bioavailability.

Before we discuss the benefits of polysaccharides, it’s important to understand the concept of bioavailability.

Bioavailability is the extent to which an active ingredient or nutrient reaches the systemic circulation to exert its effect. Or in other words, when you consume polysaccharides, how much can the body utilize their benefits?

If you ever mixed a spoonful of sugar into your cup of tea or coffee, you know that sugar dissolves well in water. Between sixty and seventy percent of the body is made up of water; therefore, compounds that are water-soluble are carried in the body easily.

Polysaccharides are relatively large sugar molecules containing thousands of sugars, which are attached and branch in different directions at different points, and cannot be absorbed in the small intestines into the blood.

A good example is astragalus; in China, it is used in IV therapy for its rapid effect on kidney inflammation. However, ingesting astragalus will not result in the same effect on the kidneys.

However, that doesn’t mean that astragalus is ineffective. Large polysaccharide molecules can be exposed to the lymphatic tissue in the GI tract and exert a direct effect on the immune system.

Starch

Starch is the most common molecule in plants and is the main way plants store energy. Digestible starch comes in two forms: amylose (linear chains of glucose) and amylopectin (branched chains of glucose). Resistant starch, however, resists digestion by pancreatic amylase and reaches the colon intact, where gut bacteria can feast on it. More on that below.

Cellulose

The name cellulose hints at the compound’s function in plants: it is the building block of plants’ cells. Humans can’t digest cellulose, but ruminating animals and some strains of gut bacteria can ferment cellulose.

Cellulose is an insoluble fiber, meaning it is hydrophobic; it does not dissolve in water and create a gel like compound. Instead, it can hold several times its weight in water, creating bulk, making cellulose a mild laxative, promoting physical and mechanical stimulation, which might cause cramps or irritate the colon.

Most of the cellulose is fermented by gut bacteria, producing short-chain fatty acids that are vital for immune modulation.

Inulin

Inulin serves as a plant energy reserve and is composed of repeated fructose units. Although inulin is not digested by humans, it is highly beneficial. It is soluble in hot water, which means it will form a gel like compound and act as a mild laxative that provides bulk without irritating the colon’s walls.

Most of the inulin we ingest is fermented by gut bacteria and ends up forming short cain fatty acids.

Plants in the Asteraceae are known to be rich in inulin. Some good examples are burdock (Arctium lappa), echinacea (Echinacea angustifolia), elecampane (Inula helenium), and dandelion (Taraxacum).

Health benefits of polysaccharides

Polysaccharides play a crucial role in the immune system, specifically in the branch of the immune system housed in the lymph, and in gut and digestive health.

A brief look at the lymphatic system

I like to describe the lymphatic system as the garbage tract and the police squad of the body.

Clean up crew

As a garbage tract, the lymphatic collects all waste products from cells, including metabolic waste, dead cells, and pathogens, and filters them in the lymph nodes, where white blood cells gobble up the solid waste, such as dead cells, bacteria, and cellular debris. The fluid is then drained into the subclavian veins, which lead to the heart. From the heart, waste products are moved in three ways

CO2 is sent to the lungs and is removed from the body when we exhale.

Water-soluble waste products are carried to the kidneys and removed in the urine.

Fat-soluble toxins are transported to the liver, where they are conjugated for elimination in the stool.

Police squad

The lymphatic system is the house and center of maturation for many white blood cells, specifically lymphocytes, which are essential for the body’s immune response, such as macrophages, B cells, and T cells.

Macrophages are part of the innate immune system, which means they act quickly but are not very specific. They can recognise and gobble up foreign protein at a glance.

B and T cells are much more advanced. It takes them longer to react because they “research” the specific pathogen and mount a response to match it. Think about them like a key and a matching lock. Their other superpower is their long memory; like a scorned woman, they never forget the pathogen that tried to invade the body.

Why does it matter?

To optimize nutrient absorption in the small intestine, the lining is a single layer of epithelial cells. Half digested foods, bacteria, and viruses that enter the body with the food, along with other waste products, can easily leak from the gut lumen through a single layer of epithelial cells into the body, increasing toxicity and causing inflammation.

To protect the body from the effects of potential leakage, the body concentrated a large number of lymphatic vessels in the gut. It is as if the body say “This is a troubled neighborhood with lots of garbage and punks, I’d rather have more garbage trucks and police cruisers circling the street.”

Large polysaccharide molecules can not be absorbed into the blood in the gut. However, when they interact with the highly concentrated immune cells in the lymphatic vessels, they profoundly affect immunity.

The gut bacteria connection

Polysaccharides are very long, complex molecules that our bodies cannot break down and digest. Our gut bacteria, though, love to feast on them.

When these critters gobble up the fiber, starch, inulin, and beta-glucan from herbs such as burdock, astragalus, and reishi, they produce short-chain fatty acids that have been shown to modulate the immune system and reduce inflammation.

The colon is the main site where gut bacteria ferment polysaccharides. It is also the place where all the toxins from the liver’s conjugation process, bile, cholesterol, and other waste products are collected, and where stool is formed.

The integrity of the colon’s epithelial walls is essential; without it, toxins can leak back into the blood, leading to a cascade of systemic reactions, including systemic inflammation, metabolic conditions (insulin resistance, weight gain), liver and brain inflammation (Depression and anxiety, brain fog, neurodegenerative diseases, and chronic fatigue)

While most gut bacteria reside in the colon, a small number live in the small intestine, especially in the lower part that leads to the colon, where they help maintain the integrity of the small intestinal lining.

Butyrate is the most common fatty acid produced by the fermentation of polysaccharides and modulates the immune system. It is associated with reduced inflammation, as measured by lower IL-6 and TNFα levels. By reducing inflammation, butyrate enhances the integrity of colon epithelial cells.

Other ways in which butrate supports a healthy colon include generating energy that colon cells can use to optimize their function, and promoting mucus production in the colon that protects the cells from wear and tear and acts as an immune barrier.

The overall effect of butrate is to protect the integrity of the colon’s epithelial lining and reduce inflammation, which carries a systemic immune-modulating effect.

Denis Burkett fiber hypothesis

Dr Denis Burkett and his colleagues (physicians Peter Cleave, G. D. Campbell, Hugh Trowell, Neil Painter, and a biochemist, Alec Walker) suggested that the Western diet, which is typically low in fiber increase the risk of Congenital heart disease, atreoscolrasis, obesity, diabetes, dental cavities and gum disease, and large bowel conditions such as cancer, appendicitis and diverticulosis.

Our ancestors, the hunter gatherers, consumed around 150 grams of fiber daily. In 1900, average fiber intake in the United States was estimated at 40-50 grams per day , with some populations consuming even more depending on their diet composition and access to refined foods. Rural populations, especially those growing their own food, likely consumed 50-70+ grams daily.

Compare that to today: the average American now consumes about 15-17 grams of fiber per day, less than half of even the conservative recommendations, and roughly one-third of what our great-grandparents ate.

Generally speaking, roots are the part of the plant where energy is stored; therefore, roots are high in polysaccharides. For our ancestors, the hunter gatherer roots were a sought after source of food because their starch kept early humans satiated longer and provided energy. However, the resistant starch, inulin, fiber, and cellulose fed the gut bacteria, reinforcing our interdependence.