There are two main type of beta glucan - yeast and mushroom.

Which type Beta Glucan is the "best"?  

Mushroom and yeast based beta glucan(s) are the most common.  Barley Beta glucan is becoming more popular to treat high cholesterol but has very little Active Linkage in it.

Mushroom beta glucan has more published research than Yeast beta glucan, but mushroom beta glucan has been used for a much longer period of time than yeast.  There really is very minimal research on any other sources of beta glucan and its effects on cancer.

The best beta glucan is likely mushroom based.  

Mushroom based beta glucan is what is used to treat cancer throughout Asia.  If you are considering Mushroom based beta glucan, there are pros and cons.

The primary benefits of mushroom based beta glucan is it is absorbed in the stomach; yeast based beta glucan is absorbed in the intestines.

Since there is no such thing as a beta glucan that is 100% Active Linkage, there are always unwanted molecules attached to the Active Linkage.

It does not really matter what is "attached" to the Active Linkage of a mushroom based beta glucan; the product will still work.  However, unwanted molecules attached to yeast based beta glucan can destroy its immune system benefits.  For this reason, mushroom beta glucan is better than yeast based beta glucan.

Mushroom Beta Glucan will likely not work for you:

The mushroom based beta glucan used to treat cancer in Asia is call PKS Kristin or PKS.  It is only sold by prescription and is covered under most health insurance plans.

You cannot buy this exact material on the internet, but you can purchase similar mushroom based beta glucan products.

What a retailer selling Mushroom beta glucan will not tell you:

The daily dose for mushroom beta glucan to treat cancer in Asia is normally based on body weight.  A 200 pound person needs to take twice the amount as a 100 pound person.

The average dose used to treat cancer in Asia is between 1.5 grams and 3 grams.  This equates to a more commonly recognized dose of 15,000 to 30,000 milligrams per day.

The daily dose is huge because Mushroom beta glucan has only about 10%, or less, Active Linkage in it.   In Asia, the material is sold in a bulk form and is normally mixed with a liquid, such as juice.  

Mushroom based beta glucan found on the Internet is normally sold in caplets (though some are sold in 1 oz liquid bottles).  It will be rare to find a product that is more than 100 mg per caplet.  Below are two examples of mushroom based beta glucan from the Internet.  

Beta Glucan (Reishi Mushroom) 100mg 120 caps $29.95 

Standardized Maitake Mushroom Beta Glucan 20 mg  60 gel caps $12.95

In order to duplicate a 15,000 milligram, or 1.5 gram, dose of Mushroom based beta glucan using 100 mg caplets, you would have to take 150 caplets a day.  If you elected to use the 20 mg caplets, you would need to take 750 caplets a day and twice these amounts, if you were attempting to obtain a 30,000 milligram or 3 gram dose.

Unless you are willing to take a substantial quantity of mushroom based beta glucan, it is unlikely it will produce any meaningful immune system benefits.  For this reason, you need to be careful of the out of text claims that might be found on a retail web site selling Mushroom based beta glucan.  Your focus should be on researching the amount of a mushroom based product needed to generate a meaningful immune response .

Yeast Based Beta Glucan has much more Active Linkage than Mushroom Beta Glucan.

Yeast based beta glucan contains a higher percentage of Active 1,3/1,6 Linkage than mushroom based beta glucans, ranging from about 20% to 90%, and costs less.

The most serious issue on Yeast based beta glucan is its level of purity - purity being defend as the actual percentage of Active 1,3/1,6 Linkage in the material.

If a yeast based product is 20% Active Linkage, 80% of the material is "something else."  The "something else" will be a small percentage of other side chain linkage molecules, such as 3,6, 2,3 linked glucose, but the vast majority of the  "something else" will be fat and protein molecules.

A 20% product will produce no immune system benefits because:  1) most of the Active Linkage is covered up with fat and protein molecules, and your immune system will never "see" or respond to it.   Your immune system simply views low purity beta glucan as another "glob" of fat/protein in your body.  The immune system only reacts to the shape of the 1,3/1,6 linked molecules.  Fat and protein simply covers up the Active Linkage.  2) The higher the percentage of fat, the less of the material will be absorbed.  

The issue of fat and protein is so critical, all the published tests on yeast based beta glucan have been done with a level of purity of 80% or higher.  There is no published proof a product with less than 80% Active 1,3/1,6 Linkage will work in humans.

This is also the reason taking twice as much of a less pure product (such as 60%) to save money, will not be as effective as a small dose of a more pure product.  

If you are going to use yeast based beta glucan as a conjunctive treatment for cancer, it would be in your best interest to confirm that its actual percentage of 1,3/1,6 linkage is equal or greater than 80%.

What dose do I need to take as a conjunctive therapy for cancer?

Beta Glucan is defined by the FDA as a "dietary supplement."  No dose information can be provided for a specific condition, and no claims can be made that it will cure anything.  This is true for any type of dietary supplement.

The normal stated dose on a bottle of beta glucan is generally two caplets a day for a 60 count bottle.  It does not matter if the product is 10 mg per caplet or 500 mg per caplet;  the general rule is the entire contents of a bottle are taken evenly over a 30 day period.

A good reference point might be obtained from reviewing dosages from the published test data.  Though the doses in individual tests vary, the most common average appears to be about 11-12 milligrams (mg) per pound of body weight.  

If you are considering beta glucan as a conjunctive treatment for cancer, we suggest you adhere to the published information on product purity and consume an amount of Active 1,3/1,6 Linkage that would be reasonable for your body weight.