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Four Sigmatic Product Quality StandardsUpdated 10 months ago

Quality is a word that resonates with most people on some level but what does it really mean? Without being defined by some standards, the word can really be used very loosely. In a dictionary, 'Quality' is defined as, "The degree of excellence in something." In the food industry, quality is generally defined as a measure of purity, strength, flavor, color, size, maturity, workmanship, and conditions. Put into layman's terms, one could say that a high-quality food product is one that is made consistently. you can consume it with confidence and know that it will not degrade your health, at least in any unexpected way.

We all face an overwhelming number of food options to choose from many times throughout the day. Some could give you a good feeling and take your health further; some could do the opposite. As a customer, it is often hard to tell these apart. With some common sense, tasting, and comparing the feeling before and after eating, you will get pretty far. The next step is to do some research and compare the different species, their optimal growing conditions, and all the details from harvesting to processing and transporting. The final step is to go to the laboratory and get it all on paper. Nowadays, it is easy, although often quite expensive, for anybody to run laboratory tests to prove if a product is clean, safe, and exactly what it is claimed to be.

Four Sigmatic has been founded to source, make and provide to people only the best, safest, and most high-quality options of nature’s amazing gifts that we first have chosen to work with (read more about our story and what our name stands for here). We want to share all the information that we have gathered and compiled during this journey. Part of our mission is to help people make good choices, and we hope that this can help in comparing different options by knowing what qualities make the difference. Below you will find our quality standards for different markers that we follow in our constant testing regime.


Let’s take the example of a carrot. The final product might look bright orange and juicy on the store shelf, but how are you supposed to be able to tell if the cells of that vegetable are saturated with pesticides or heavy metals? What about the beta-carotene concentration compared to the hyper-local-demeter carrots next to them? Or how can you actually even know that the species is really the cultivated carrot (Daucus carota subsp. sativus) and not the wild carrot (Daucus carota)? Then of course there are the purple, white and yellow carrots and so on… Surely, some of these things may not matter much to you, and some others might have gotten hardwired to your sensorial responses, so that you immediately know to make the right decision, sometimes just going for the one that “feels the best”. But the point here is that even with something as common as the carrot, there are a lot of things that make a difference. In part, we feel like these similar aspects become even more important when talking about functional mushrooms, which we pay a lot of money for and look to receive noticeable benefits from.


Everything starts with finding and working closely with the best possible partners. We make sure all of the raw material suppliers and all of our packing facilities are properly certified and regularly audited. All of our products are produced according to the GMPs (Good Manufacturing Practices).

Good Manufacturing Practices (GMPs) are guidelines enforced by the FDA that govern the manufacturing process of a product to ensure that the quality and safety are consistent. GMP covers all aspects of production from the used materials, facilities, and equipment to the training and personal hygiene of staff. By documenting and consistently following the detailed, written procedures at each step in the manufacturing process, we ensure the quality of each batch of our products. In addition to the laboratory testing required by the different GMPs, we extend these testings to certified independent laboratories for other contaminants such as heavy metals, unwanted bacteria and yeasts, mycotoxins, and pesticide residues.

The quality and safety of a product might not always be just the sum of its parts. Even if all of the raw materials used were top-notch, there could be contamination during processing or packing. Right before shipment, the products could be “accidentally” irradiated, or the manufacturer’s quality screening wasn’t accurate enough. That is why we at Four Sigmatic make sure, by our own outsourced 3rd party testing, that the quality is what we want it to be.

Our complete quality control program also includes identity testing (“fingerprint”) for all of the raw materials that go into the products, inspection of the incoming ingredients, moisture content and dissolution rate tests, and personally taste-testing each batch that comes out. Before any product leaves our warehouse, we always make sure that all the test results are in.

Quality is much too important to be left to the quality control department alone. It is essential that everybody in the company has the same premise and commitment to producing only the best possible products. Also, doing things right the first time adds absolutely nothing to the cost of a product.


Here is a shortlist of how we ensure that our products are safe, effective, and top-notch in every possible way:

  • Dedicated sourcing and finding the best partners with proper certifications
  • Certificates and well-maintained records from the suppliers, manufacturers, and third-party labs
  • In-house recipe creation
  • Potency testings (beta-glucans, triterpenes, adenosine, cordycepin, betulinic acid, etc.)
  • Allergen testing
  • Organoleptic and macroscopic analysis - taste, smell, and appearance of the raw ingredients and finished products
  • Strict standards and the unique packaging of the products that make the difference in preserving the quality and potency of our mushrooms for up to three years
  • Constant laboratory testing to ensure that every product meets strict requirements for microbial quality, heavy metals, mycotoxins, pesticides, and is not irradiated


Pretty much everything we eat nowadays has heavy metals absorbed in them. For example, the earth’s crust contains trace amounts of arsenic and lead naturally and purposefully. Also, some of the heavy metals are necessary for humans (e.g., copper, zinc). Unusually high amounts cannot be claimed as “naturally occurring,” since there is always a human intervention or other reason behind those cases that should be addressed.

The four heavy metals that are considered the most toxic and are most commonly tested include arsenic, cadmium, lead, and mercury. Other commonly encountered elements that are classified as heavy metals include antimony, chromium, cobalt, copper, nickel, selenium, silver, thallium, and zinc.

In general, long-term exposure to heavy metals can have carcinogenic, central and peripheral nervous system and circulatory effects. Depending on the metal and dose involved, the effects can vary significantly.

Remember that what you do the most, counts the most. The food that is eaten in hundreds of grams should be the cleanest. Supplements and boosters that are only a small fraction of your diet are not going to kill you, though it is definitely not a reason for these products to not to be as clean as possible. We don’t want to accumulate any of the heavy metals inside us because they can cause stress and strain on the body and decrease our health.


Heavy metal test results are presented in amounts of parts per million or fractions of them, even in parts per billion. These fractions address the quantity-per-quantity measure of the tested element in the sample. This same presentation applies to pesticide testing and mycotoxins testing.


One part per million is equal to one drop of water diluted into 50 litres


One part per billion is the same as three seconds out of a century

For each of the markers, you can find our internal limits that we have chosen to follow. Some of them are considerably lower than the official recommendations because we would rather be on the safe side as we have the chance to be with some attention paid and work done.


Arsenic is an abundant metalloid (an element that has properties in between those of metals and nonmetals) that makes up about 1.5 ppm of the Earth’s crust. However, arsenic is classified as a carcinogen (an agent directly involved in causing cancer) and “dangerous for the environment.” This heavy metal is known to adversely affect the liver, nervous system, skin, and digestive system.

The main commercial use of arsenic is for strengthening copper and lead. It is also used in electronic devices, preserving wood, and in the production of pesticides. Arsenic contaminates the soil and groundwater, which is why the banning of its use has started recently. Most people end up ingesting most of their arsenic through drinking water but other significant sources can also be some vegetables, fruits, and rice.

We ensure and guarantee that each batch of our products always contain LESS THAN 1 PPM OF ARSENIC.


Cadmium is a stable metal that occurs in minor amounts in nature. As cadmium doesn’t corrode easily, it has many uses including batteries, metal coatings, and plastics. Since this heavy metal is officially considered toxic, and as batteries have taken a huge leap forward recently, the popularity of cadmium has luckily been decreasing.

Mainly because of the modern metal industry and zinc production, bigger cadmium concentrations get accumulated in the atmosphere and in plants. In certain areas of developing countries, bad air pollution results in products contaminated with high levels of cadmium. Also, products harvested from the ocean often contain this toxic heavy metal. Cadmium is known to harm the liver, kidneys, and the immune system.

We ensure and guarantee that each batch of our products always contain LESS THAN 0.1 PPM OF CADMIUM.


Lead is a naturally occurring bluish-grey metal found in small amounts in the earth’s crust. If ingested, lead is poisonous and it is known to cause a lower IQ and cause damage to the nervous system. The use of lead has been dramatically reduced in recent years but still is a common pollutant in many foods.

Lead is used in the production of batteries, ammunition, and metal products (solder and pipes). Previously, the biggest reason for high lead pollution in the air was the lead-infused gasoline used in cars which are now banned. Nowadays, the main environmental source of lead is air pollution from factories.

We ensure and guarantee that each batch of our products always contain LESS THAN 1 PPM OF LEAD.


Mercury is literally a heavy metallic element and the only one that stays as a liquid at standard conditions. It is commonly known as quicksilver because of this property. On a gram-per-gram basis, mercury is, by far, the most toxic of all the heavy metals. It can affect neurological, developmental, and renal (kidney) systems.

Often, mercury accumulates in our diets by eating specific fish and shellfish. Main industrial uses for mercury include thermometers, fluorescent lamps, and amalgam dental restorations. Concern about the toxicity of this heavy metal have led to its reduced use and it is even partly banned in some countries. Mercury is the most toxic in its organic forms such as dimethylmercury and methylmercury.

We ensure and guarantee that each batch of our products always contain LESS THAN 0.05 PPM OF MERCURY.


Some ten thousand years ago, our ancestors came up with the idea of harnessing microbial food cultures to preserve and improve their foods. Humans have continued to develop and try to control these processes and today, many of the world’s most loved foods require fermentation: chocolate, coffee, cheese, bread, yoghurt, beer and wine, tobacco, ketchup... Some of the absolute favorite foods of the Four Sigmatic gang include sauerkraut, kefir, kombucha, preserved wild foods, and other home-fermented goodies!

These important cultures of live bacteria, yeasts, and molds are called good cultures. Then, there are the “not-good” cultures, which include several pathogens, that can take over our food and make it spoil.

Every product on the store shelves goes through many different stages where it could be contaminated with unwanted bacteria and pathogens. The only way to prevent spoilage is proper hygiene and caution in every stage of manufacturing and handling. If the food is prone to spoilage, the temperature of the area where the food is handled and transported also plays a big role.

Test results for microbial quality address the amount of different good and bad bacteria in a product that could cause it to go rancid or result in food poisoning or other harm to a consumer. The microbial quality can and should be tested for several different parameters. Below are some additional details about four different tests that are commonly done.


Colony-forming unit (CFU) is a term used in microbiology to give a rough estimate of the number of viable bacteria or fungal cells. It specifies the cells that are still viable to multiply and leaves out the dead cells. Most of the probiotic supplements being sold contain at least 20 billion (20 * 10^9) cfu of “good bacteria” per serving.


This is the total biological activity of a sample. It is the count of all bacteria, fungi (molds), and yeasts that are present and growing in the product. Some of these unwanted pathogens could include common bacteria that cause influenza, fever, or stomach flu. Sanitary and precise tracking, especially during packaging, is important to prevent any contamination.

Testing for total plate count is done by first leaving the sample to grow for 24 hours in 37 degrees Celsius to imitate the conditions inside a human body.

10^4 cfu/g is a general limit set by several authorities for food supplements and by the American Herbal Product Association (AHPA) for herbal extracts and supplements. Usually, for unprocessed food, the limit is up to 10^7 cfu/g.

We ensure and guarantee that each batch of our products always has a total plate count of LESS THAN 10 000 (10^4) CFU/G.


This is the total biological activity of all the yeasts and molds in a sample. It is the same as the total plate count but without the bacterial count. The large group of microscopic yeasts and molds include several hundred species which can result in deterioration of foods. So yes, we test our mushrooms also to be free of other unwanted fungal friends.

10³ cfu/g is a general limit set by several authorities for food supplements and by AHPA for herbal extracts.

We ensure and guarantee that each batch of our products always has LESS THAN 1 000 (10³) CFU/G OF MOLDS AND YEASTS.


Unwanted pathogenic bacteria such as coliforms, E. coli, Salmonella, and Staphylococcus aureus can cause food poisonings, skin infections, respiratory disease, and other problems that are easily prevented by ensuring the purity of anything that is sold to be ingested.

We ensure and guarantee that each batch of our products is ALWAYS FREE OF THE MOST COMMON PATHOGENS.


Mycotoxins are, according to their name, toxins formed by yeasts and other fungi. The specific strains of fungi generally produce these compounds to weaken the receiving host for easier proliferation (growth). Usually, the poisons contained in many species of wild mushrooms are excluded from the discussions of mycotoxicology, and these are not relevant here either as we have already ensured that the mushrooms used are the correct species. The focus here is on the mycotoxins created by microfungi.

The health concerns caused by mycotoxins can be acute or chronic. For humans, many mycotoxins can cause bad symptoms such as cardiovascular and nervous system diseases, weight gain, decreased fertility, and cancer. Unfortunately, common sources of mycotoxins in people's lives are indoor environments (i.e. moldy buildings).

Many common foods, including but not limited to corn, grains, peanuts, and coffee are often contaminated with unseen molds and the mycotoxins created by them. Mycotoxins are resistant and usually don’t break down by digestion, so they usually remain in the food chain especially in meat and dairy products. Even heating and/or freezing does not destroy some mycotoxins. It is a common practice to add clay to foods and feeds in order to absorb the mycotoxins and reduce the possible harm caused by them. Another possible approach is to deactivate the mycotoxins with enzymes, other yeasts, or bacteria.

For only about the last 50 years, we have been detecting and learning more about many of the mycotoxins. They are not new though, as the first known mycotoxin, penicillin, was discovered in 1928. Here is an interesting story that luckily made things change:

In 1960 on an English farm, about 100,000 turkeys died. Further examination into the cause of death showed the primary food source, peanut meal was infected with Aspergillus flavus. - - Chemical investigation into the cause of death showed the production of four toxic chemicals, named aflatoxins after being discovered in A. flavus. Turkey autopsies showed aflatoxins targeted the liver and either completely killed the tissue cells or induced tumor formation. The discovery of aflatoxins changed agricultural practices on how grains and legumes were grown, harvested, and stored. (Hudler, George W. (1998). Magical mushrooms, Mischievous Molds)

Obviously many conventional farmers use a lot of different fungicides to prevent these unwanted molds to grow. This results in higher levels of pesticides (see below).

In the case of functional mushrooms, we think that it is crucial to test and guarantee that there are no unwanted mycotoxins in the products. As the mushrooms are cultivated, basically the environment is made optimal for many kinds of fungi to grow in, though we only want the one functional mushroom species to establish and proliferate. In this aspect again, the quality starts from the beginning - preventing and eliminating any contaminated growth or moldy mushrooms that might have occurred. After processing, it is essential to run comprehensive mycotoxin testing to show the purity of the product and the absence of mycotoxins.

Currently, more than 400 mycotoxins have been documented, and new ones are being identified all the time. The most important ones from the point of view of human health are aflatoxins, ochratoxins, fumonisin, HT-2, T-2, vomitoxin (deaxynicalenol), and zearalenone. We ensure and guarantee that each batch of our products meets the following limits:

AFLATOXINS, total (B1, B2, G1, G2) <4 ppb


FUMONISIN, total (B1, B2, B3) <100 ppb

HT-2 <30 ppb

T-2 <5 ppb

VOMITOXIN (deaxynivalenol) <50 ppb



The term pesticide applies to a wide array of substances used for plant protection such as insecticides, fungicides, herbicides, and nematocides. There are hundreds, if not thousands of pesticides used in agriculture, and some residue might make its way to the final consumer in the product.

Different chemicals have different half-lives. This means that they break down at different paces. The half-life ranges from a few days to many months. Detectable amounts of residue on a product depend on how recently the plants or mushrooms have been sprayed before the harvest.

Testing the safety of different pesticide residues in our food has the same issue as food additives. These chemicals are being tested only one at a time and claimed to be safe that way. But no one knows what happens when you put five or fifteen of them together. Good things usually have good synergistic effects, but bad things most likely have really bad cumulative effects.

Of course, organic farming practices limit the amount and types of pesticides used. We still run independent third-party lab testings for over 400 markers of pesticide residues, even for our 100% certified organic products to ensure and guarantee that they are FREE OF PESTICIDE RESIDUES AND MEET THE STRICT USP36<561> REQUIREMENTS & ORGANIC REGULATIONS.


Irradiating food with energy-rich radiation such as gamma rays and electron beams is sometimes done to sterilize food and prolong shelf-life. This is quite common practice in many developing countries but in the US and EU, people don’t want their food to be broken down and altered at the atomic level. In the USA, any food that is irradiated or contains irradiated food ingredients must be labeled.

There is quite a lot of debate over the harmful effects of food irradiation. The official statement is that the food is not left with radioactivity even though the process is usually done with a gamma ray produced by radioactive isotope Cobalt-60 or Cesium-137. Even if that were true, why should the daily consumables last for weeks or months?

In the basic irradiation process, the bulk or packaged food passes through a radiation chamber on a conveyor belt. The food does not come into contact with radioactive materials, but instead passes through a radiation beam, like a large flashlight. The amount of radiation used depends on the type of food and the specific purpose of the irradiation. The speed of the belt helps control the dose delivered to the food by controlling the exposure time.

The most commonly used physical techniques to analyze foods for irradiation are photo-stimulated luminescence (PSL) and thermoluminescence (TL). PSL and TL detect light which is emitted from irradiated minerals like silicates upon stimulation with light (PSL) or heat (TL). PSL is a fast and reliable screening method, but a positive result on PSL still requires TL to confirm if the sample has been irradiated.

We ensure and guarantee that NONE OF OUR PRODUCTS ARE EVER IRRADIATED.


Even though it is not always possible to keep track of everything—well, life sure is full of surprises—Four Sigmatic is based on the principle that the products offered are of the highest quality and no compromises are made. We are heavy users ourselves of all of our products, and obviously, we want to be sure that they are clean and safe to take!

We hope that you continue to love our products and it is our honor to serve great things to great people.

Remember that as a customer, you are voting with your wallet. It is important to start demanding to know what we are putting into our bodies. Require the manufacturers and suppliers to test their products and openly show those test results. Buy only the best quality stuff when possible. Grow and forage more of your own food. Share this information. Still, detox. Drink good water. Be grateful. Enjoy life. <3


Not finding what you’re looking for? Please feel free to reach out to our Customer Success Team at [email protected] or (213) 699-4616 and we’d be happy to help!

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