Several factors are believed to bring about changes in the cell's DNA leading to Non Hodgkins Lymphoma.

The causative factors inducing non-Hodgkins lymphoma is not clearly understood. Cancers in general are caused by changes in a cell's DNA such as translocations or deletions. These changes induce a normal cell to become malignant and it begins to divide in an uncontrolled manner.

But what triggers these changes?

1. Virus- Two viral agents have been understood to play a role in causing NHL. They are:

 Epstein-Barr virus (EBV)- 1-2 % of those who are immuno- suppressed immediately after organ transplantation or those who have HIV/AIDS, test positive for EBV. These individuals are also at a greater risk for developing NHL. In these cases, the lymphoma regresses once the immuno deficient status is corrected. EBV is positive in most cases of African pediatric Burkitt's lymphoma.

 Human T-cell lymphoma/leukemia virus (HTLV-I) - It is understood that individuals who are infected early in life with the HTLV have a 3 % chance of developing T-cell lymphomas or leukemias, and diseases related to the central nervous system.

2. Other possible causes

A few of the NHL causes listed below are yet to be scientifically proven. Nevertheless all of them are strong contenders for the role of causative agents.

 Herbicides/Pesticides, including the household variety, are believed to play a role in causing cancer

 Evidence indicates that nitrates present in drinking water may give rise to NHL.

 Some studies show that hair dyes may play a role in causing NHL. However there is no unanimous support to corroborate this theory.

 A few studies indicate that there is a possible connection between high consumption of milk or meat and NHL development. This has however not been supported by other studies.

 Long-term use of illegal drugs, tobacco and alcohol have been shown by some to increase an individual's chances of developing the disease.

 Other infections, such as those with Helicobacter Pylori, are capable of predisposing a person to develop certain lymphomas, like those affecting the Mucosa Associated Lymphoid Tissue (MALT).

 There is a greater risk among the elderly to develop NHL after a blood transfusion. This could arise from the inability of their immune system to cope with foreign blood products.

 A familial history of lymphoma or leukemia predisposes an individual to develop NHL, two to three fold.

 Certain speculations exist regarding a link between NHL and illnesses like asthma, tropical celiac disease, certain types of arthritis and allergies.

 Continuous antigenic or immune system stimulation could trigger NHL and other related illnesses.

 Age diminishes the efficiency of the immune system, which is rendered incapable of repairing the damages inflicted by the toxic agents on the DNA.