Can Eating Too Many Fish Increase Your Risk of Getting Melanoma?
Experts and researchers agree that skin cancer-related findings are not sure enough to remove fish from the menu.
The increased risk of melanoma may be associated with fish biocontaminants, such as arsenic and mercury, rather than the fish themselves.
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Eating high amounts of fish, including tuna and fried fish, may be linked to a higher risk of developing malignant melanoma, according to a new study. The study, published June 9 in Cancer Causes & Control, tracked nearly half a million people over a 15-year period and found that the highest number of edible fish was associated with a higher incidence of fatal skin cancer
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"This study is important because it is very large and possible by design, which means that fish diets were tested before cancer progression," said author Eunyoung Cho, ScD, associate professor of dermatology and epidemiology at Brown University in Providence, Rhode Island, on release.
Melanoma is the fifth most common cancer in the United States, with a lifelong risk of 1 in 38 white people, 1 in 1,000 black people, and 1 in 167 people in Hispanic, according to the American Cancer Society. (ACS). Almost all people who die of skin cancer are from melanoma - an estimated 7,650 Americans will die of skin cancer by 2022, according to the American Academy of Dermatology Association (AAD).
It is important to note that the authors of the study do not look at the findings as a reason to avoid eating fish, and both ACS and AAD agree that the most important way to reduce the risk of skin cancer is to reduce exposure to the sun and avoid bed bugs. .
Consumption of tuna and fish was linked to an increased risk of melanoma - but fried fish were not
To examine the relationship between fish consumption and the risk of melanoma, the authors analyzed data collected from 491,367 adults from across the United States who enrolled in the NIH-AARP Diet and Health Study of the National Cancer Institute between 1995 and 1996. years, and more than 90 percent were white.
Participants reported how often they ate fried fish, fried fish, and tuna during the past year, and the size of their portions. According to the U.S. Food and Drug Administration (FDA) (PDF), the size of a fish feed is 4 ounces (oz), or 112 grams (g) - about the size of the palm of your hand. The cancer register was used to quantify the incidence of new melanoma that occurred over an average of 15 years.
The researchers listed a number of factors that could influence outcomes, such as income and education, BMI (body weight index), physical activity levels, smoking history, family history of cancer, daily alcohol consumption, caffeine and calories, and a ultraviolet. radiation levels in the local area of each participant.
During the study period, 5,034 participants (approximately 1 percent) developed malignant melanoma and 3,284 (0.7 percent) developed melanoma stage. Stage 0 of melanoma (also called melanoma in situ) has not yet penetrated the upper layer of the skin, according to the American Cancer Society.
The researchers found that a high dietary intake of raw fish and tuna was associated with an increased risk of malignant melanoma and stage 0 melanoma. Organization is a statistical link; findings do not prove that eating fish has caused further harm. The group that ate the most fish - about 3 servings a week - had 22 percent more malignant melanoma.
The researchers then looked at certain types of fish consumption and the risk of melanoma.
Compared to those with an average daily tuna diet - almost 0.3 g (0.01 oz), those with daily tuna intake of 14.2 g (0.5 oz) were at a 20 percent higher risk of malignant melanoma and a higher risk percentage. 17 stage 0 Melanoma.
Compared with an average diet of 0.3 g of raw fish per day, a diet of 17.8 grams (0.62 grams) of uncooked fish per day was associated with an 18 percent higher risk of malignant melanoma and a higher risk of 25 percent. in stage 0 melanoma.
The researchers did not identify any significant associations between the use of fried fish and the risk of malignant melanoma or stage 0 melanoma.
“This is impressive research; one strength of this study is to look at a large number of patients, although it is important to note that this data was not collected from studies designed to assess the risk of melanoma; it was primarily a study of nutrition, ”said Jeffrey Weber, MD, PhD, oncologist and co-director of the Melanoma Research Program at NYU Langone Health in New York City. Drs. Weber was not part of the study. That means that that was not the data collected about many known risk factors for developing melanoma, such as sunburn or sun exposure, eye color, number of moles or freckles, and hair color, he says.
Experts Say There Is No Reason to Avoid Fish
"The associated risk increase found here was very low - a 20 percent difference between low fish and high fish consumption," Weber said. A 20 per cent increase in risk risk means that if the incidence of melanoma is usually one in 50 people, it could be one in 42 people, he said.
Weber also points out that there are other findings in the study that appear to be inconsistent. “For example, why would there be an increase in the risk of tuna and fish diets but not fried fish? I love fish, especially good fish taco, and I will not change my eating habits on the basis of these findings, and I would not recommend anyone to do so, ”he said.
Can Mercury Pollution in Fish Contribute to the Risk of Melanoma Risk?
These findings indicate an organization that needs to be investigated further, said Dr. Cho. Researchers believe that increased risk may be related to fish biocontaminants, such as arsenic and mercury, rather than to the fish themselves.
“Previous research has found that eating too much fish is associated with higher levels of this contamination and has been linked to higher levels of this risk and higher risk of skin cancer. However, we note that our research did not investigate the prevalence of this contamination in participants' bodies so further research is needed to confirm this relationship, ”said Cho.
In a 2020 study of 29,000 adults (PDF), Cho and colleagues found a link between mercury and nonmelanoma skin cancer. Participants with high levels of mercury in their blood were 79 percent more likely to report melanoma-free skin cancer compared to people with very low levels of melanoma.
Although the study did not show that fish or contaminants were the cause of the increased risk, there is evidence that exposure to toxins may be associated with an increased risk of melanoma, Weber said. “We have found that 9/11 survivors are at high risk of melanoma. The accident was not caused by exposure to the sun, but rather by the toxins or substances that people were exposed to after the explosion which may have affected the skin's ability to repair the damage, ”he said.
According to the current study on fish consumption, there is no known link between possible contamination in some fish and the risk of melanoma, Weber said.
Reducing Sun Exposure Is The Best Way To Reduce The Risk Of Melanoma
The best way to reduce the risk of melanoma is to reduce your exposure to UV radiation, says Weber. That means when you are enjoying the outdoors, seek shade, use sunscreen or UV-resistant clothing, wear a hat, and avoid the sun during the day when the rays are very strong.