The Swiss Study Group for Complementary and Alternative Methods in Cancer (SKAK) and the Swiss Cancer League (SCL) is warning against the theories and products of Matthias Rath, M.D. According to the report, Rath claims that:
- Diseases arise when the balance between mechanisms breaking down and building the connective tissue shifts towards breakdown. If disease organisms or cancer cells can dissolve the surrounding connective tissue, a disease may spread in the body.
- The plasminogen activator/plasmin system plays a critical role in this process: the reaction chain results in the activation of collagenase, which breaks down collagen. By gaining access to the blood vessels, cancer cells can then spread in the circulatory system.
- The body can normally block enzymes that destroy connective tissue by means of two mechanisms: with the intrinsic enzymatic block or with the help of nutritional supplements.
- Nearly all people suffer from a chronic vitamin deficiency.
- Almost all diseases are caused by a lack of lysine and vitamin C. Lysine can allegedly suppress the plasmin-induced proteolysis by occupying the binding sites on plasminogen. In diseases, the body's production of proline becomes insufficient, which is why this amino acid also has to be consumed. The name "Cellular Health" was chosen because the nutritional supplements target the body's cells as their active site.
- The mechanism of cancer spread that he has identified is the decisive breakthrough in blocking cancer and a breakthrough in the struggle against infectious diseases (including AIDS) and virtually all other diseases .
The SKAK/SCL report concludes that Rath's underlying assumptions have never been scientifically tested and, based on current state knowledge, a cancer-preventing or curing action is not proven for any of his products, which cannot be legally marketed in Switzerland.
Rath also claims that conventional cancer therapy has never demonstrated a life-prolonging effect and often accelerates the disease's progress. This statement is false. Ads he has placed in many large newspaper have praised "natural health" methods and described the war against Iraq as part of a conspiracy to create a climate of fear that would enable the "drug cartel" to remain viable .
In 2000, the British Advertising Standards Authority upheld a complaint against claims in a Matthias Rath Ltd. newsletterâ€”"GOOD HEALTH, do it yourself"â€”which had stated that the company's vitamins could prevent heart attacks, strokes, high blood pressure, and other conditions mentioned in the newsletter . In 2002, the agency upheld a complaint against a claim by the Health4Us Foundartion of Emeryville, California, which had advertised in a British press that Rath's "remarkable natural approach is capable of controlling the spread of cancerous cells in the human body without damaging healthy cells." 
In 2005, the Advertising Standards Authority of South Africa ordered the Dr. Rath Foundation Africa to stop advertising that dietary supplements are safer and more effective than chemotherapy against HIV infections. The challenged ad, published in the November 26, 2004 Mail & Guardian, was headlined "Why should South Africans continue to be poisoned with AZT? THEREâ€™S A NATURAL ANSWER TO AIDS.â€ The objectionable claims included:
- AZT has been found to cause children in utero to develop brain damage, neurological disorders, dparalysis, mental retardation, epilepsy, other serious diseases, and early death.
- Daily doses of multivitamins slow down HIV disease and cut the risk of developing AIDS in half.
- Non-patentable natural therapies have very low profit margins.
- Every textbook of biochemistry recoignizes that vitamins and other micronutrients are the most decisive factor determining optimum function of the immune system .
- Dr. Matthias Rath's Cellular HealthÂ™. Berne, Switzerland: Swiss Cancer League, 2003.
- Dr. Rath's Open Letter Campaign. Dr. Rath Health Foundation Web site, accessed Aug 26, 2003.
- Details.htm?adjudication_id=30238 Matthias Rath Ltd. British Advertising Standards Authority adjudication, Nov 8, 2000.
- Details.htm?adjudication_id=34819 Health4Us Foundation. British Advertising Standards Authority adjudication, Oct 30, 2002.
- Ruling of the ASA Directorate in the Matter between Treatment Action Center and Dr Rath Health Foundation Africa, March 9, 2005