Functional mushrooms: nature that works and why reishi is at the top

What Are Functional Mushrooms and Why They Aren’t “Just” Food

The term functional mushrooms refers to types of fungi that contain bioactive compounds with physiological effects, thus transcending basic nutritional value. They are not food in the conventional sense. They are closer to adaptogens: natural substances that help the body establish balance, adapt to stress, and support key systems.

Functional Mushrooms Include:

• Reishi (Ganoderma lucidum): traditionally known as the “mushroom of immortality”

• Chaga (Inonotus obliquus): rich in antioxidants

• Lion’s Mane (Hericium erinaceus): known for its potential effects on cognitive function

• Cordyceps (Cordyceps sinensis/militaris): often associated with energy and endurance

• Turkey Tail (Trametes versicolor): rich in immunomodulating polysaccharides

Each has its own “specialty”, but one name appears repeatedly in the literature, tradition, and modern science.

Reishi: 2,000 Years Old and More Relevant Than Ever

Ganoderma lucidum, or simply reishi (its Japanese name), has been recognized in Chinese medicine for at least 2,000 years. It was called ling zhi (灵芝), which translates as “mushroom of spiritual power” or “divine fungus”.

In classical Chinese texts, including the Shen Nong Ben Cao Jing (a Chinese herbal compendium from the 1st or 2nd century AD), reishi is classified in the category of “superior medicines”, substances that are taken long-term to maintain health without side effects.

Active Compounds: What Reishi Actually Contains

Reishi’s efficacy is neither secret nor myth. It rests on well-documented bioactive compounds, and each plays its own role.

1. Triterpenoids: Ganoderic Acids

Triterpenoids are one of the main reasons reishi is so special. Ganoderma lucidum contains more than 150 different triterpenoid compounds, of which the ganoderic acids (A, B, C, and D) are the most extensively studied.

Documented Effects:

• Inhibit pro-inflammatory pathways

• Support liver function, with documented hepatoprotective effects

• Neutralize free radicals as antioxidants

• Support immune function in both in vitro and animal studies

Triterpenoids are alcohol-soluble, which means that extraction method and preparation form are key. Water extractions do not isolate these compounds as effectively as dual extraction (water + alcohol).

2. Beta-Glucans: Immunomodulatory Polysaccharides

Beta-glucans are polysaccharides found in the cell walls of fungi, yeasts, and certain grains. In the context of reishi, the most studied are the beta-1,3/1,6-glucans, which:

• Modulate the immune system: activate macrophages, NK cells, and dendritic cells

• Act as PAMPs (pathogen-associated molecular patterns): activate immune cell receptors such as Dectin-1

• Are well tolerated and safe for long-term use

Beta-glucans are water-soluble, meaning that standard water extraction captures them effectively.

3. Adenosine: Cardiovascular Support

Reishi also contains adenosine, a purine nucleoside that plays a role in:

• Supporting normal heart rhythm

• Promoting vascular relaxation

• Influencing sleep quality, as adenosine is one of the key endogenous regulators of sleepiness

What Western Science Says: Overview of Key Research

Reishi is not solely the domain of traditional medicine. Over the past two decades, the number of published studies has increased exponentially.

Immune System

A systematic review published in the Cochrane Database of Systematic Reviews (Jin et al., 2016) analyzed the effects of reishi preparations on cancer patients. The authors concluded that reishi “could be recommended as an alternative adjuvant treatment in combination with cancer therapy”, highlighting the immunostimulatory effects of polysaccharides.

Separate studies have shown that polysaccharide extracts of reishi increase NK cell (natural killer cell) activity and stimulate the production of interleukins.

Stress and Anxiety

A pilot clinical study (Tang et al., 2005) showed that patients with neurasthenia reported statistically significant improvement in fatigue and well-being after eight weeks of taking reishi extract compared to placebo.

Reishi triterpenoids are being studied as potential modulators of the HPA axis (hypothalamic-pituitary-adrenal axis), the system that regulates the body’s response to stress.

Sleep

Animal studies have shown that water extracts of reishi prolong total sleep duration, particularly the NREM phase, which coincides with the role of adenosine and certain polysaccharides in sleep regulation.

Antioxidant Protection

Reishi also contains lucidenic acids and various phenolic compounds, which, together with ganoderic acids, exert antioxidant effects. The study of oxidative stress in the context of aging and chronic diseases is an area where reishi demonstrates a promising profile.

How to Choose a Quality Reishi Preparation

With the mushroom and adaptogen market booming, the difference between high-quality and subpar products is significant. What to pay attention to:

Extraction Method

• Water extraction → isolates beta-glucans (polysaccharides)

• Alcohol extraction → isolates triterpenoids (ganoderic acids)

• Dual extraction → optimal, as it captures both groups of compounds

Part of the Mushroom

• Fruiting body → contains higher concentrations of active substances

• Mycelium → less expensive, often cultivated on grains, which lowers the concentration of active substances and adds carbohydrates from the substrate

Origin and Cultivation

• Organic cultivation reduces the risk of contamination with heavy metals and pesticides

• Mushrooms are bioaccumulators and absorb substances from their environment

Who Is Reishi Suitable For?

Reishi is one of those natural adaptogens that provide long-term support to the system rather than forcibly stimulating it.

Individuals who have traditionally benefited from reishi, and whom current evidence supports:

• People under chronic stress who are seeking natural support without “chemicals”

• Those who wish to support their immune system, especially during transitional seasons

• Individuals with sleep disturbances who are looking for a natural alternative

• Active individuals who pay attention to long-term resilience of the body

• Older adults who invest in preventive health

Why Reishi Is More Than a Trend

Reishi is not a product of a marketing wave. It is a mushroom with a documented 2,000-year history, a growing body of Western clinical and preclinical evidence, and clearly defined bioactive compounds.

In a world where stress has become a chronic state and the search for balance is a necessity, not a luxury, reishi offers precisely this: support and balance.

Sources and Literature

1. Jin X. et al. (2016). Ganoderma lucidum (Reishi mushroom) for cancer treatment. Cochrane Database of Systematic Reviews. DOI: 10.1002/14651858.CD007731.pub3

2. Tang W. et al. (2005). A randomized, double-blind and placebo-controlled study of a Ganoderma lucidum polysaccharide extract in neurasthenia. Journal of Medicinal Food, 8(1), 53–58.

3. Wachtel-Galor S. et al. (2011). Ganoderma lucidum (Lingzhi or Reishi): A Medicinal Mushroom. In: Benzie IFF, Wachtel-Galor S (eds.) Herbal Medicine: Biomolecular and Clinical Aspects. 2nd ed. CRC Press.

4. Gao Y. et al. (2003). A Phase I/II Study of Ling Zhi Mushroom Ganoderma lucidum Extract in Patients with Type II Diabetes Mellitus. International Journal of Medicinal Mushrooms, 6(1).

5. EFSA (European Food Safety Authority). Health claims: Article 13 and 14 claims. Available at: https://www.efsa.europa.eu/en/topics/topic/health-claims

6. Regulation (EC) No 1924/2006 of the European Parliament and of the Council of 20 December 2006 on nutrition and health claims made on foods.

7. Batra P. et al. (2013). Probing Lingzhi or Reishi Medicinal Mushroom Ganoderma lucidum (Higher Basidiomycetes): A Bitter Mushroom with Amazing Health Benefits. International Journal of Medicinal Mushrooms, 15(2), 127–143.

8. Cui X.Y. et al. (2012). Extract of Ganoderma lucidum prolongs sleep time in rats. Journal of Ethnopharmacology, 139(3), 796–800. DOI: 10.1016/j.jep.2011.12.020

The content of this blog is for informational purposes only and does not replace professional medical advice. Food supplements are not medicines and are not intended for the treatment, prevention, or alleviation of diseases.