Study: High-Fiber Diet May Help Some Melanoma Patients

Key TakeawaysResearch has shown that a high-fiber diet contributes to a healthy gut and immune system.A new study has found that patients with melanoma who are receiving immunotherapy to treat their cancer may have a better response to treatment if they eat a high-fiber diet.Most people benefit from a diet that includes many plant-based whole foods, even if they do not have cancer.

Key Takeaways

Research has shown that a high-fiber diet contributes to a healthy gut and immune system.A new study has found that patients with melanoma who are receiving immunotherapy to treat their cancer may have a better response to treatment if they eat a high-fiber diet.Most people benefit from a diet that includes many plant-based whole foods, even if they do not have cancer.

New research fromThe University of Texas MD Anderson Cancer Centerhas found that people who are receiving immunotherapy for melanoma skin cancer may have better outcomes if they eat a high-fiber diet that’s made up of mostly plant-based foods.

The findings were in line with those from previous studies that had shown having a healthy balance of certain gut bacteria improves the immune responses of people with melanoma.

What Is Melanoma?

What the Study Found

For the new study, the researchers looked at gut bacteria from 438 melanoma patients.Most of the patients had late-stage cancer and were getting systemic cancer therapy. All of the patients were having their tumor response and survival kept track of.

Of the patients in the study, 128 provided data on their dietary habits and were being treated withimmune checkpoint inhibitors.

The researchers put the patients into two groups: One group ate a sufficient amount of fiber (at least 20 grams per day), and the other group ate less than 20 grams of fiber per day. Their fiber intake came from fruits, vegetables, whole grains, and legumes.

Patients who did not eat enough fiber had shorter progression-free survival rates than the patients who did eat enough fiber daily. For every 5-gram increase in daily fiber consumption, the patients had a 30% decreased risk of melanoma progression or death.

The researchers also looked at whether taking certain kinds of supplements that may benefit the gut microbiome would have any effect on patient outcomes. They concluded that taking probiotic supplementsdid not improveoutcomes for patients in the study.

Should You Try a Probiotic Supplement?

What Is the Gut Microbiome?

Thegut microbiomerefers to all the different microbes that live in our intestinal tract. They play a major role in digestion, immunity, and inflammation. Recent studies have shown that our gut microbiome may even affect our heart health.

Jennifer Wargo, MDA healthy balance of bacteria in the gut can change and enhance our immunity.

Jennifer Wargo, MD

A healthy balance of bacteria in the gut can change and enhance our immunity.

Jennifer Wargo, MD, MMSc, director of theInnovative Microbiome and Translational Researchprogram at The University of Texas MD Anderson Cancer Center, told Verywell that having a balanced gut microbiome goes hand-in-hand with having a strong immune system.

Flavonoid-Rich Foods Could Improve Gut Health

“Within our bodies, we have trillions of microbes that outnumber our cells, and a lot of them sit in our gut," said Wargo. “You have the gut microbiome, and on the other side, you have immune cells. A healthy balance of bacteria in the gut can change and enhance our immunity.”

Here’s an example of what that could mean for your health: Some studies have suggested that taking antibiotics before getting a flu shot can decrease your immune response to the vaccine.

Sharing “Good” MicrobesAfecal transplantis a procedure where stool with a good balance of bacteria from a healthy donor is transferred to a person who is having treatment.Wargo said that these transplants may help patients with melanoma achieve better treatment outcomes.

Sharing “Good” Microbes

Afecal transplantis a procedure where stool with a good balance of bacteria from a healthy donor is transferred to a person who is having treatment.Wargo said that these transplants may help patients with melanoma achieve better treatment outcomes.

Afecal transplantis a procedure where stool with a good balance of bacteria from a healthy donor is transferred to a person who is having treatment.

Wargo said that these transplants may help patients with melanoma achieve better treatment outcomes.

Another example applies to people undergoing cancer treatment. Immunotherapy treatments for cancer help a patient’s immune system fight the cancer cells.

For patients with cancer who are undergoing immunotherapy, a healthy digestive system supports a stronger immune system, which could lead to a better response to treatment. According to Wargo, gut microbes could also affect a cancer patient’s response to chemotherapy and radiation.

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Fiber and Gut Health

Fiber is food for the bacteria in your gut. The more fiber you eat, the healthier, more diverse, and more active your microbiome will be.

Carrie Daniel-MacDougall, PhD, MPH, associate professor of epidemiology at The University of Texas MD Anderson Cancer Center, told Verywell that many of the foods your gut microbes like are good for your body in general.

Jennifer Wargo, MDYour diet and what you put into your body matters.

Your diet and what you put into your body matters.

New Research Shows Eating Avocados Supports a Healthy Gut

There are also some things that you may put in your body that can deplete your gut microbes. For example, while antibiotics have a place in treating various health conditions, research has shown that using them indiscriminately canaffect the balance of gut bacteria.

Therefore, Wargo warned against the overuse of antibiotics, as it has the potential to do long-term harm to the microbiome and immune system.

Eating Yogurt May Protect Your Gut Health While on Antibiotics

Finding the Best Diet for Each Patient

Each person living with cancer has different needs. In the same way that one treatment may not work for everyone, the dietary needs of each person will be different, too.

Wargo said that people being treated for cancer “shouldn’t take matters into their own hands” when it comes to making decisions about their diet. In some cases, a patient may not be able to follow a high-fiber diet safely.

Luckily, most cancer treatment teams include a registered dietician, who can help patients figure out which diet will be the best fit for them.

Why Your Gut Flora Matter to Your Health

Should You Take Fiber or Probiotic Supplements?

For people who want (and safely can) increase their fiber, there are ways to do so besides eating more fiber-rich foods, mostly in the form of supplements.

However, fiber from whole foods provides broader benefits than you’d get from the fiber that’s found in supplements. Similarly, probiotic supplements are not necessarily better at restoring your helpful gut microbes than the probiotics you’d get naturally from food like yogurt and kefir.

“Prebiotic and probiotic foods seem to behave differently than supplements or pill form,” said Daniel-MacDougall. “Dietary supplements which often deliver specific nutrients or bacteria types in high doses should not be taken without careful discussion as they may have unintended effects.”

What Can the “Blue Poop Challenge” Tell You About Your Gut Health?

Benefits Beyond Cancer

Wargo said the study’s findings could be applied more broadly: the authors believe that having a healthy gut microbiome could lead to better outcomes for patients with other types of cancer, too.

The bottom line? Don’t wait until you get sick to start thinking about how your diet affects your health and wellbeing. The food you eat is, in a way, its own kind of medicine. It may even help prevent some negative health outcomes.

“We can all learn something from this,” said Wargo. “Your diet and what you put into your body matters. I don’t think there’s any substitute. We all need to eat well.”

What This Means For YouNew research has shown that some patients with melanoma might have a better response to treatment if they eat a high-fiber diet that supports their gut microbiome.However, a high-fiber diet is not the best fit for everyone. Before increasing how much fiber you eat, talk to your doctor—especially if you’re being treated for cancer.

What This Means For You

New research has shown that some patients with melanoma might have a better response to treatment if they eat a high-fiber diet that supports their gut microbiome.However, a high-fiber diet is not the best fit for everyone. Before increasing how much fiber you eat, talk to your doctor—especially if you’re being treated for cancer.

New research has shown that some patients with melanoma might have a better response to treatment if they eat a high-fiber diet that supports their gut microbiome.

However, a high-fiber diet is not the best fit for everyone. Before increasing how much fiber you eat, talk to your doctor—especially if you’re being treated for cancer.

6 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Spencer CN, McQuade JL, Gopalakrishnan V, et al.Dietary fiber and probiotics influence the gut microbiome and melanoma immunotherapy response.Science. 2021;374(6575):1632-1640. doi:10.1126/science.aaz7015Gopalakrishnan V, Spencer CN, Nezi L, et al.Gut microbiome modulates response to anti–PD-1 immunotherapy in melanoma patients.Science. 2018;359(6371):97-103. doi:10.1126/science.aan4236Asnicar F, Berry SE, Valdes AM, et al.Microbiome connections with host metabolism and habitual diet from 1,098 deeply phenotyped individuals.Nature Medicine. 2021;27(2):321-332. doi:10.1038/s41591-020-01183-8Hagan T, Cortese M, Rouphael N, et al.Antibiotics-driven gut microbiome perturbation alters immunity to vaccines in humans.Cell. 2019;178(6):1313-1328. doi:10.1016/j.cell.2019.08.010Johns Hopkins Medicine.Fecal transplantation (bacteriotherapy).National Center for Complementary and Integrative Health.Probiotics: What you need to know.

6 Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Spencer CN, McQuade JL, Gopalakrishnan V, et al.Dietary fiber and probiotics influence the gut microbiome and melanoma immunotherapy response.Science. 2021;374(6575):1632-1640. doi:10.1126/science.aaz7015Gopalakrishnan V, Spencer CN, Nezi L, et al.Gut microbiome modulates response to anti–PD-1 immunotherapy in melanoma patients.Science. 2018;359(6371):97-103. doi:10.1126/science.aan4236Asnicar F, Berry SE, Valdes AM, et al.Microbiome connections with host metabolism and habitual diet from 1,098 deeply phenotyped individuals.Nature Medicine. 2021;27(2):321-332. doi:10.1038/s41591-020-01183-8Hagan T, Cortese M, Rouphael N, et al.Antibiotics-driven gut microbiome perturbation alters immunity to vaccines in humans.Cell. 2019;178(6):1313-1328. doi:10.1016/j.cell.2019.08.010Johns Hopkins Medicine.Fecal transplantation (bacteriotherapy).National Center for Complementary and Integrative Health.Probiotics: What you need to know.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

Spencer CN, McQuade JL, Gopalakrishnan V, et al.Dietary fiber and probiotics influence the gut microbiome and melanoma immunotherapy response.Science. 2021;374(6575):1632-1640. doi:10.1126/science.aaz7015Gopalakrishnan V, Spencer CN, Nezi L, et al.Gut microbiome modulates response to anti–PD-1 immunotherapy in melanoma patients.Science. 2018;359(6371):97-103. doi:10.1126/science.aan4236Asnicar F, Berry SE, Valdes AM, et al.Microbiome connections with host metabolism and habitual diet from 1,098 deeply phenotyped individuals.Nature Medicine. 2021;27(2):321-332. doi:10.1038/s41591-020-01183-8Hagan T, Cortese M, Rouphael N, et al.Antibiotics-driven gut microbiome perturbation alters immunity to vaccines in humans.Cell. 2019;178(6):1313-1328. doi:10.1016/j.cell.2019.08.010Johns Hopkins Medicine.Fecal transplantation (bacteriotherapy).National Center for Complementary and Integrative Health.Probiotics: What you need to know.

Spencer CN, McQuade JL, Gopalakrishnan V, et al.Dietary fiber and probiotics influence the gut microbiome and melanoma immunotherapy response.Science. 2021;374(6575):1632-1640. doi:10.1126/science.aaz7015

Gopalakrishnan V, Spencer CN, Nezi L, et al.Gut microbiome modulates response to anti–PD-1 immunotherapy in melanoma patients.Science. 2018;359(6371):97-103. doi:10.1126/science.aan4236

Asnicar F, Berry SE, Valdes AM, et al.Microbiome connections with host metabolism and habitual diet from 1,098 deeply phenotyped individuals.Nature Medicine. 2021;27(2):321-332. doi:10.1038/s41591-020-01183-8

Hagan T, Cortese M, Rouphael N, et al.Antibiotics-driven gut microbiome perturbation alters immunity to vaccines in humans.Cell. 2019;178(6):1313-1328. doi:10.1016/j.cell.2019.08.010

Johns Hopkins Medicine.Fecal transplantation (bacteriotherapy).

National Center for Complementary and Integrative Health.Probiotics: What you need to know.

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