Milk thistle is the common name of a plant known scientifically as Silybum marianum. This plant contains seven major compounds, the best understood of which are called silybin A, silybin B, isosilybin A, and isosilybin B.

Silymarin, which is extracted from the seed shell of the milk thistle plant, is the name used to refer to the combination of the four compounds above.

Studies on silymarin have shown that it has many beneficial medical properties, including:

• Reducing inflammation

• Reducing oxidative stress

• Reducing lipid peroxidation

• Resisting bacteria

• Chelating (binding) iron

• Modulating immunity

• Inhibiting angiogenesis (creation of new blood vessels)

• Decreasing tumor invasion

• Counteracting multidrug resistance (MDR)

• Protecting normal tissues from chemotherapy drug damage

• Lowering prostate specific antigen (PSA)

• Protecting the brain

• Increasing tissue resistance against radiation (radioresistance)

• Sensitizing cancer cells to chemotherapy agents

Most of these benefits result from silymarin’s ability to alter various cell-signaling pathways that regulate cell function. This is particularly important for preventing and treating cancers.

One of the chief obstacles to using silymarin in powder capsules is that it is poorly absorbed in that form.

Newer compounding techniques include binding the silymarin with a lipid molecule that makes it much more absorbable as well as more bioavailable. Siliphos is a high-absorption form of silymarin available without a prescription.

The dose is one capsule three times a day with meals.

Another technique is to nanosize the molecule, making it very tiny — a process that greatly increases the extract’s bioavailability and even its penetration into cells.