Can eating whole small fish protect against cancer?

For this study, researchers analyzed food frequency questionnaire data from more than 80,000 participants – about 34,500 men and 46,000 women – aged 35 to 69 in Japan. Based on the questionnaires, the scientists noted how often the study participants ate whole small fish.

The researchers followed the participants for an average of nine years, during which approximately 2,400 participants died, with approximately 60% attributed to cancer.

At the study’s conclusion, scientists found that there was a significant reduction in all-cause death and cancer among participants who habitually ate small, whole fish.

When researchers took into account lifestyle habits that could impact mortality risk, such as smoking, BMIAnd alcohol consumptionthey found that participants who frequently ate small fish were less likely to die from any cause.

According to researchers, it is common in Japan to eat small fish, including small horse mackerel, fry, Japanese smelt and sardines, whole, including organs, bones and heads.

“Previous studies have revealed the protective effect of fish consumption on health, including mortality risks,” says Chinatsu Kasahara, PhD, professor in the Department of Preventive Medicine at Nagoya University School of Medicine. in Japan and principal investigator of this study. “However, few studies have focused on the effect of consuming small fish specifically on health outcomes. This subject interested me because I have been used to eating small fish since my childhood. I now feed them to my children.

Smaller fish have the advantage of being sustainable because they are not normally overfished like larger fish and generally have lower mercury levels.

“I regularly recommend eating small fish because of their impressive nutritional value and lower levels of toxic mercury compared to larger fish,” Molly Rapozo, RDN, registered dietitian nutritionist and senior nutrition and health educator at the Pacific Neuroscience Institute at Santa Monica, California. , who was not involved in this study, said Medical news today.

“Small fish are part of traditional Japanese and Mediterranean diets, both touted for their longevity,” she said.

In addition to being a healthy source of protein, small fish also provide a variety of nutritional benefits, including omega-3 fatty acids and micronutrients such as calcium, vitamin A, iron, zinc and vitamin B12.

“The health benefits that have been associated with fish in general, such as it being a rich source of essential and protective nutrients such as protein and healthy fats such as omega-3 fatty acids, as well as a source of calcium from bones and a host of other vitamins and minerals have been pretty consistent in research,” explained Monique Richard, MS, RDN, LDN, registered dietitian nutritionist and owner of Nutrition-In-Sight. MNT.

“Often when someone eats small, cold-water fish, they also choose other foods that complement the health benefits of fish, such as fruits, vegetables and whole grains,” Richard continued.

“Small fish generally don’t lend themselves well to being breaded, fried and served with chips, but they are more delicate and naturally portion controlled. They tend to have a richer, savory taste on the palate, which lends itself to slower eating, savoring bites and perhaps needing less to feel satisfied,” she said. .

“This study adds to existing evidence on fish consumption and cancer mortality. We have seen in previous studies that regular fish consumption is associated with a reduced risk of gastrointestinal cancersin addition to being a potential advantage for cancer survivors who eat a diet rich in fatty fish.
—Molly Rapozo, RDN

“This type of research is important because what we eat has a significant impact on chronic diseases. Lifestyle changes, such as dietary choices, present an opportunity to reduce the risk of early death and disability. Evidence-based dietary strategies offer a practical approach to reducing the burden of chronic diseases, including cancer, and improving longevity,” said Rapozo.

MNT also spoke with Anton Bilchik, MD, PhD, surgical oncologist, chief of medicine and director of the gastrointestinal and hepatobiliary program at Providence Saint John’s Cancer Institute in Santa Monica, California, about this study.

Bilchik said he found the study interesting that eating whole small fish could offer protective factors against the development of cancer.

“But I think it’s very early in terms of… what exactly that means, what a tiny little fish is in terms of anti-cancer chemicals, vitamins, and the big cancer buzzword in this moment is inflammation. So, in a whole fish, are there various compounds and vitamins that have an anti-inflammatory effect? But there is still a lot to be resolved,” he said.

With many young people being diagnosed with cancer, especially colorectal cancer, Bilchik said it’s important that researchers continue to find new ways to protect the body against cancer, including through diet .

“The usual causes such as obesity, smoking, family history, are not frequently found in these young people diagnosed,” he explained. “So the only other potential link that we can look at is diet at a young age – whether these people who get early-stage cancer, like colorectal cancer, eat processed foods, are exposed to factors environmental factors that can influence cancer at any given time. a young age.

“So there is a lot of work to be done to better understand why so many young people are diagnosed with cancer, particularly colorectal cancer,” Bilchik added.

While eating small whole fish may be a normal dietary practice in Japan, the same cannot be said for other countries such as the United States or Europe.

When thinking about cold-water fish that contains less mercury, heavy metals and other contaminants, but is also quite versatile, flavorful and readily available, Richard said to remember the acronym SMASH – sardines, mackerel , anchovies, salmon and herring. .

Richard recommends adding a 3 to 4 ounce serving of fish or four to five small fish to:

• a piece of whole grain toast or crackers
• on a salad
• folded into a whole grain like farro, buckwheat, long-grain or brown rice, or quinoa
• added to vegetable soups, stews or pastas
• pureed as a spread or pâté

“A multitude of options are now available in most grocery stores, with canned or jarred variations using spices, oil, herbs, or a combination of enhancements. Go out and experiment – ​​SMASH could be the new spice of life! » added Richard.