In sharp contrast, the study revealed that diets high in dietary fiber - tomatoes, broccoli, vegetables, et al - were associated with a reduced risk of NHL.
"An association between dietary intake and NHL is biologically plausible because diets high in protein and fat may lead to altered immunity, resulting in increased risk of NHL," said principal investigator Tongzhang Zheng, associate professor of epidemiology and environmental health at Yale School of Medicine. But the antioxidants found in vegetables and fruits may result in a reduced risk of about 40 per cent, he added.
The news may find a tepid response from proponents of the burgeoning Atkins-style dietary regime - that promotes meat and egg consumption - currently estimated to be followed by 59 million Americans.
The Yale study, conducted between 1995 and 2001 on 601 Connecticut women between the ages of 21 and 84 diagnosed with varying subtypes of NHL, used a food frequency questionnaire developed by the Fred Hutchinson Cancer Research Center.
Each participant was asked to characterize her usual diet in the year prior to being interviewed. The FFQ collects consumption frequency and portion size data for approximately 120 foods and beverages and is periodically updated to reflect US food consumption patterns and major market changes.
After completion, the FFQ was sent to the Fred Hutchinson Cancer Research Center for calculating average daily nutrient intakes. The study included a control group of 717 women.
"So far, risk of NHL associated with animal protein and fat intakes has only been investigated in American women, in three studies," said Zheng. "If the association could also be demonstrated in American men, it would provide important information towards understanding the cause of NHL."
The full findings are published in the March 2004 issue of the American Journal of Epidemiology (volume 159,issue 5, pp454-466).