Cancer cells need lots of energy to grow quickly, and what we eat plays a big role in whether cancer develops. Scientists have found that eating too much processed food, red meat, and sugar increases cancer risk, while eating plenty of fruits, vegetables, and whole grains may protect us. For people already fighting cancer, good nutrition becomes even more important to help their bodies handle treatment better. This research shows that while food alone can’t cure cancer, eating well is a key part of both preventing cancer and helping people recover.

The Quick Take

  • What they studied: How the food we eat affects cancer risk and how nutrition helps people with cancer
  • Who participated: This is a review article that looked at many different studies about diet and cancer, not a single study with participants
  • Key finding: Unhealthy diets high in processed foods and sugar increase cancer risk, while healthy diets with lots of plants appear to lower it
  • What it means for you: Eating more fruits, vegetables, and whole grains and less processed food may help reduce your cancer risk. If you have cancer, good nutrition can help you handle treatment better and maintain strength

The Research Details

This is a review article, which means scientists looked at many different research studies about nutrition and cancer to understand what we know overall. Instead of doing one new experiment, the authors gathered information from existing research to explain how food affects cancer development and treatment. This type of study is helpful because it combines findings from many different studies to give us a bigger picture of how diet and cancer are connected. The review focuses on how cancer cells change their metabolism (the way they use energy) and how the nutrients we eat can either increase or decrease cancer risk through different biological pathways in our body.

Understanding how nutrition affects cancer is important because cancer is one of the biggest health problems worldwide. Since many people can change their diet, knowing which foods help prevent cancer and which ones increase risk gives people practical ways to protect their health. For people already dealing with cancer, good nutrition can help them stay strong during treatment and may improve their chances of recovery.

This is a review article published in a respected scientific journal, which means it summarizes what experts currently know about nutrition and cancer. However, because it reviews many different studies rather than conducting new research, the strength of any single finding depends on the quality of the studies it discusses. The article acknowledges that more research is needed, which is honest about the current limits of our knowledge.

What the Results Show

The research shows that what we eat significantly influences cancer risk through several pathways in our body. Diets high in processed foods, red meat, saturated fats, and added sugars are linked to increased cancer risk. These unhealthy diets can cause chronic inflammation (long-term swelling in the body), insulin resistance (when the body doesn’t respond well to insulin), and obesity—all of which are known to increase cancer risk.

On the positive side, eating a balanced diet rich in fruits, vegetables, whole grains, legumes, and healthy fats appears to protect against cancer. These foods contain vitamins, minerals, fiber, and special plant compounds called phytochemicals that help protect our cells. They work by fighting harmful molecules called free radicals, preventing damage to our DNA, and helping control how cells grow and divide.

For people with cancer, nutrition becomes even more critical. Cancer and its treatments can change how the body processes food and what nutrients it needs. Personalized nutrition support can help patients maintain a healthy weight, keep their muscles strong, and better tolerate cancer treatments. This support may improve their overall health status and potentially help them live longer.

The review highlights that obesity itself is a major cancer risk factor, connecting excess body weight to hormonal imbalances and changes in how the body uses energy. The research also emphasizes that nutrition works through multiple biological mechanisms—including reducing inflammation, controlling oxidative stress (cellular damage), boosting immune function, and regulating hormones. These multiple pathways explain why diet has such a powerful effect on cancer risk.

This review aligns with and builds upon previous research showing that diet is one of the most modifiable risk factors for cancer. The findings support long-standing nutritional guidelines that recommend eating mostly plant-based foods and limiting processed foods. The emphasis on personalized nutrition for cancer patients reflects a growing shift in cancer care toward tailored treatment approaches.

This is a review article rather than a new study, so it depends on the quality of previously published research. The abstract doesn’t specify exactly which studies were reviewed or how many. While the connections between diet and cancer are well-established, individual responses to diet can vary. The review notes that nutrition is not a cure for cancer and should be part of a complete treatment plan. More research is still needed to understand exactly how to optimize diet for each type of cancer and for individual patients.

The Bottom Line

Eat more fruits, vegetables, whole grains, and legumes while limiting processed foods, red meat, and added sugars (High confidence). Maintain a healthy weight through balanced eating and physical activity (High confidence). If you have cancer, work with a nutrition specialist to create a personalized eating plan (High confidence). Remember that good nutrition supports cancer prevention and treatment but is not a replacement for medical care (High confidence).

Everyone should care about this research because diet affects cancer risk for all of us. People with a family history of cancer, those who are overweight, and people currently being treated for cancer should pay special attention. If you have cancer or are at high risk, talk to your doctor or a registered dietitian before making major diet changes.

Cancer prevention through diet is a long-term investment—it typically takes years of healthy eating to significantly reduce cancer risk. For people with cancer, improvements in treatment tolerance and strength may be noticed within weeks to months of improved nutrition. Long-term benefits like reduced recurrence risk develop over months and years.

Want to Apply This Research?

  • Track daily servings of fruits and vegetables (goal: 5+ servings daily) and weekly servings of processed foods (goal: reduce to fewer than 3 servings weekly). Log these in your app to see patterns over time.
  • Start by adding one extra serving of vegetables to one meal each day, and replace one processed snack with a whole food option each week. Use the app to set reminders and celebrate small wins.
  • Weekly check-ins on diet quality, monthly tracking of energy levels and how you feel, and quarterly reviews with your healthcare provider if you have cancer or are at high risk. Use the app to identify which dietary changes feel most sustainable for you.

This article reviews scientific research about the relationship between nutrition and cancer but is not medical advice. Nutrition alone cannot prevent or cure cancer. If you have cancer, are at high risk for cancer, or are considering major dietary changes, please consult with your doctor or a registered dietitian nutritionist before making changes. This information should complement, not replace, professional medical care and treatment recommendations from your healthcare team.