The Mediterranean Diet May Improve Response Rates to Immunotherapy

Our understanding of nutrition’s effects on health grows daily. Many patients, relatives and healthcare workers place their hopes in particular diets or supplements for preventing or treating disease. Scientific research shows that many expectations are exaggerated, although a few diets, such as the Mediterranean and MIND diets, stand out for their health benefits.

According to a new study, the Mediterranean diet may improve outcomes in melanoma, a rare, biologically aggressive skin cancer subtype, by increasing immunotherapy response rates and progression-free survival.

We anticipate that diet may play an important role in immunotherapy’s future success. Clinical trials are now expanding to examine different diets across tumour types, including digestive cancers.

Adherence to a Mediterranean diet rich in monounsaturated and polyunsaturated fats from olive oil, nuts and fish, along with polyphenols and fibre from vegetables, fruits and whole grains, was significantly associated with better response to immune checkpoint inhibitor immunotherapy in advanced melanoma.

What Is an Immune Checkpoint Inhibitor?

Immune checkpoint inhibitors are drugs that block checkpoint proteins such as PD-1 and PD-L1 on T cells and some cancer cells. They aim to prevent cancer cells from appearing friendly to the immune system and activate immunity against cancer. These antibody-based medicines are a form of immunotherapy and are administered by infusion.

This multicentre study by researchers in the United Kingdom and the Netherlands recorded dietary intake in 91 patients with advanced melanoma treated with immune checkpoint inhibitors and followed their progress with regular oncological imaging.

In addition to its significant association with overall immunotherapy response, the Mediterranean diet was significantly associated with progression-free survival, the duration of disease control on treatment, at month 12.

How Might Diet Affect Immunotherapy Response?

Laura Bolte of University Medical Center Groningen, who presented the study, emphasised that immune checkpoint inhibitors have helped revolutionise treatment across many cancers, adding: “Our study highlights the importance of dietary assessment in people with cancer starting immune checkpoint inhibitor treatment and supports the role of dietary strategies in improving outcomes and survival.”

The study also found that eating whole grains and legumes may have reduced the likelihood of immune-related adverse effects from immunotherapy, such as colitis. By contrast, red and processed meats were associated with a higher likelihood of immune-related adverse effects.

The relationship of immunotherapy response with diet and the gut microbiome offers hope and an exciting future for improving treatment responses. More clinical trials are investigating how high-fibre diets, plant-based eating, protein- and fat-rich diets, and various supplements affect immunotherapy response rates. These studies could help more patients benefit from immunotherapy in the future.