Some experts are skeptical of the research, but they say a healthy diet in general will lower cancer risks.
Eating more organic foods may help lower your overall risk of developing cancer, suggests a new study.
The research involved 68,946 French volunteers beginning in 2009.
The participants answered questions about the foods they ate and how often they chose organic over non-organic.
In 2016, those who most frequently ate organic food products, including produce, meat, and dairy, had 25 percent fewer cancers than adults who never consumed organic foods.
The researchers concluded that “a higher frequency of organic food consumption was associated with a reduced risk of cancer.”
“Although the study findings need to be confirmed,” the researchers wrote, “promoting organic food consumption in the general population could be a promising preventive strategy against cancer.”
The study was published in
The study authors noted several limitations in their work.
For example, those who volunteered for the study were well educated and likely more health conscious than the general population.
Seventy-eight percent of the participants were female.
Notably, the researchers didn’t check pesticide residue levels of the participants.
They also pointed out that the questionnaire was not validated, so it’s difficult to understand what was actually being measured.
Self-reported intake of organic foods doesn’t necessarily translate into lower pesticide exposure.
Dr. Timothy Byun is an oncologist with The Center for Cancer Prevention and Treatment at St. Joseph Hospital in California.
He told Healthline that the major strength of the French study is its large sample size. But it’s limited, due to its reliance on questionnaires.
“There were no urine or blood tests to actually measure a person’s pesticide exposure and correlating with organic food consumption,” he explained.
Like the Harvard experts, Byun said it’s not clear if there is a benefit of organic food for cancer prevention.
The Harvard commentary states that there are dietary factors that are known to reduce cancer risk.
“I agree with the American Cancer Society recommendation of a healthy diet rich in fruits, vegetables, reduction of red meat and processed meat, alcohol intake moderation, smoking cessation, and regular exercise,” said Byun.
He believes a vegetable-based diet or Mediterranean type diet is best.
Dietitian Kailey Proctor also works with patients at St. Joseph Hospital.
“At the end of the day, I really just want my patients or those looking to reduce their risk of cancer, to eat fruits and vegetables,” she told Healthline.
“Americans don’t eat enough to begin with so I’d rather people focus on increasing how many they are eating, compared to not eating an apple because it isn’t organic and instead opting for organic potato chips,” she said.
Proctor said that some vegetables and fruits have more pesticide exposure than others.
She suggests checking the Environmental Working Group’s (EWG) Dirty Dozen.
Updated every year, the list includes those fruits and vegetables with the most pesticide residues.
“This is helpful for consumers who want to eat more organic but can’t afford to eat all organic produce, meats, poultry, and dairy. For 2018, the top five are strawberries, spinach, nectarines, apples, and grapes,” said Proctor.
EWG also publishes a yearly Clean Fifteen list of fruits and vegetables with the least pesticide residues.
Organic foods are often more expensive than non-organic. And in some parts of the country, fresh produce of either type is difficult to get.
When that’s the case, Proctor advises that frozen fruits and vegetables are just as nutritious as fresh.
“Sometimes they have more vitamins, minerals, and antioxidants because they are flash-frozen at the peak of harvest so they retain their nutrition compared to produce that has to be transported across the country,” she explained.
She said that canned vegetables and fruits are also good options. Vegetables packed in a salt brine should be rinsed. Fruits should be packed in their own juice rather than in heavy syrup.
“If you have access to a farmers market, that is another way to shop for produce. You get to know the farmer, how they grow their crops, and support the local economy,” said Proctor.
The EWG recommends washing produce thoroughly in cold water to minimize exposure to toxic pesticides.
In the United States, the U.S. Food and Drug Administration (FDA) doesn’t regulate the term “organic” on food labels.
Administered by the U.S. Department of Agriculture (USDA), the National Organic Program is responsible for developing standards for organically produced agricultural foods.
The agency makes sure that foods with the USDA organic seal meet uniform standards. But they don’t address food safety or nutrition.
“The term organic is a federal guideline that crops are not grown with pesticides or synthetic fertilizers,” said Proctor.
“For animals, organic means that their living conditions are similar to their ‘natural behavior’ and they are not given antibiotics or hormones,” she continued.
When you come across a USDA seal that says “Made with organic….,” it means that at least 70 percent of the ingredients were organically produced (not including salt and water).
“Organic” on the seal means the product contains at least 95 percent organic ingredients. There’s also a “100 percent organic” seal.
“Natural” is another word found on food packaging, but consumers need to dig deeper.
There are no formal regulations for use of the word on food products. It does not mean the food is organic.
“It is a huge marketing word because food companies know that if they use ‘natural,’ consumers are more inclined to think the product is healthier. Foods that contain highly processed sweeteners, such as high fructose corn syrup, can be considered natural,” said Proctor.
“I try to meet my patients where they are at in terms of eating organic or conventional produce. I just encourage consumers to try to increase their consumption of fruits and vegetables,” she added.