Is there an association between obesity and Non-Hodgkin's Lymphoma (NHL)?

From the Guidelines

Obesity is likely to increase the risk of developing non-Hodgkin lymphoma (NHL), as it creates a state of chronic inflammation and alters immune function, which may contribute to lymphoma development. The relationship between obesity and NHL is complex, and while obesity itself doesn't directly cause NHL in all cases, maintaining a healthy weight through balanced diet and regular physical activity may help reduce the risk of developing NHL along with many other health conditions. According to the American Cancer Society guidelines on nutrition and physical activity for cancer prevention 1, overweight and obesity contribute to 14% to 20% of all cancer-related mortality, and evidence suggests that obesity increases the risk of developing many cancers, including certain types of lymphoma.

Some key points to consider include:

• Obesity is thought to affect the risk of cancer through various mechanisms, including effects on fat and sugar metabolism, immune function, and levels of several hormones 1
• Studies have found that individuals with higher body mass index (BMI) may have a modestly increased risk of certain NHL subtypes, particularly diffuse large B-cell lymphoma
• The risk appears to be dose-dependent, with higher BMI correlating with greater risk
• Weight management should be considered as part of an overall health strategy for disease prevention, as recommended by the American Society of Clinical Oncology 1

Overall, while the evidence is not yet definitive, maintaining a healthy weight is likely to be beneficial in reducing the risk of developing NHL and other health conditions.

From the Research

Obesity and Non-Hodgkin Lymphoma (NHL) Risk

• The relationship between obesity and the risk of Non-Hodgkin Lymphoma (NHL) has been explored in several studies 2, 3, 4, 5, 6.
• A study published in 2007 found that overweight/obesity probably increases the risk of NHL, whereas moderate physical activity may reduce risk 2.
• Another study from 2007 reported that higher adult BMI was associated with an increased risk of NHL, particularly for those who were class 2 obese (BMI ≥ 35.0 kg/m²) 3.
• A meta-analysis conducted in 2007 found that excess body weight is associated with an increased risk of non-Hodgkin's lymphoma, especially of diffuse large B-cell lymphoma 4.
• A case-control study published in 2005 found that high body mass index (BMI) was positively associated with diffuse NHL, but not with follicular or all NHL combined 5.
• A pooled analysis from the InterLymph Consortium in 2008 found that severe obesity was not associated with NHL overall, but an excess risk was observed for diffuse large B-cell lymphoma 6.

Key Findings

• Obesity is associated with an increased risk of NHL, particularly for diffuse large B-cell lymphoma 3, 4, 6.
• Physical activity may reduce the risk of NHL 2, 5.
• The relationship between obesity and NHL risk may vary by histologic subtype 4, 6.
• Height was positively associated with risk of all NHL combined, and suggests a role for early life nutrition in NHL risk 5.

Study Limitations

• The studies had varying sample sizes and study designs, which may affect the generalizability of the findings 2, 3, 4, 5, 6.
• The measurement of BMI and physical activity may be subject to bias and error 2, 3, 4, 5, 6.