Can diet help with advanced breast cancer? All indications are positive, researchers say

Women with breast cancer who ate an exclusively plant-based diet lost weight, improved cholesterol levels and other important metabolic factors, had less fatigue, and found they felt mentally sharper and better overall.

The results come from a small study by researchers at the University of Rochester Medical Center and the Wilmot Cancer Institute. Study participants were individuals with stage 4 breast cancer, who will undergo lifelong treatment.

These patients are typically excluded from nutritional studies, but as the number of survivors increased presented an opportunity to make both a short- and long-term impact, said study leader Thomas M. Campbell, MD, assistant professor of Family Medicine at URMC and a expert in using plant-based diets to improve health.

What did the clinical trial require?

The study included 30 patients who received stable treatment and could tolerate food.

Researchers randomly divided participants into two groups: one received standard care and the intervention group ate meals provided by the research team for eight weeks. The diet consisted exclusively of fruits, vegetables, whole grains (including whole wheat pasta), legumes (beans), potatoes, and nuts and seeds. The participants agreed to avoid animal foods (meat, eggs and dairy products) and all oils and added solid fats. They also took a daily multivitamin.

Weekly assessments took place and the study reported 95% compliance.

“It is exciting to see that these major dietary changes were achievable, well tolerated and acceptable to the clinical trial participants,” Campbell said.

There was no calorie restriction. Individuals were encouraged to eat “on plan” foods as often as they wanted.

How a clean, plant-based diet makes a difference

The women started with an average BMI of 29.7, which is on the borderline of obesity. The patients in the plant-based group lost 1 to 2 pounds per week for eight weeks, without mandatory exercise.

This is important because people with breast cancer often gain weight during treatment, which is risky. Why? Too much body weight increases insulin levels and hormones (estrogen and testosterone) in the blood, which can cause cancer.

Another encouraging study result: Researchers saw a decrease in blood samples of IGF-1, a growth factor that has been linked to common cancers, as well as less inflammation.

“While we cannot yet say from this small study whether the diet can stop cancer progression, we have seen preliminary results that indicate beneficial changes in the body, which is very positive,” said Campbell.

To better understand the implications for cancer growth, the team is collaborating with Isaac Harris, Ph.D., at Wilmot, on a bench-to-clinic study.

Scientists know that cancer cells depend on amino acids to survive, and the patients who followed the plant-based diet showed changes in their blood levels of amino acids. Harris studies the effect of amino acid composition on the survival of cancer cells, and the effect of the amino acids on various cancer drugs.

The news Research and treatment of breast cancer published the primary study, which is believed to be the first of its kind. The breast cancer study had sufficiently significant results that two additional articles on the nutritional intervention were also published: second study in the same magazine, and a third study in Limits in nutritionall in March 2024.

How to start making healthy changes

Patients should consult their oncologists or health care providers first before making major dietary changes, Campbell said. This is especially important for people taking blood thinners or insulin medications.

Examples of foods provided in the breast cancer clinical trial included peanut soba noodles, steel-cut oatmeal, banana flax muffins, sweet potato enchiladas, and Mediterranean white bean soup.

To get started with plant-based recipes and meal ideas that are simple and affordable, Campbell recommends these websites: plantyou.com, shaneandsimple.comAnd monkeyandmekitchenadventures.com.

Several factors influence a person’s motivation to eat healthier, Campbell added, including family support, taste preferences and cooking ability.

Whether someone makes dramatic changes overnight, or simply decides to swap an occasional meal for a plant-based recipe, this can be a good choice: ‘You only need five to ten plant-based recipes that are easy, delicious and be useful. enough to make them regularly so that your diet gets a substantial overhaul,” he said.

Higher food costs are often cited as a reason to forgo a plant-based diet, but in 2023, co-author Erin Campbell, MD, published a separate study showing that the diets that led to the greatest health improvements – including Dietary Approaches to Stop Hypertension, or the DASH diet, which is also plant-based – were the same or cheaper in terms of food costs compared to standard American diets of ultra-processed foods and take-out.