By Arthur A. Burley 
Fish is an excellent choice if you want to maintain a healthy diet. Fish is rich in protein and low in saturated fat. It also contains omega-3 fatty acids, vitamin D, and many other nutrients. Consuming more fish may mean consuming fewer foods high in harmful fats and a higher number of calories. Nutritionists often recommend eating more seafood (and fewer cheeseburgers) to improve your diet. Nutrition guidelines encourage fish as a part of a healthy diet.
It’s not surprising, then, that a new Cancer Causes and Control study has suggested a link between eating seafood and skin cancer. This is especially true since the greatest known risk factor for developing melanoma, however, is sun exposure. Your risk of developing melanoma is doubled if you have five or more sunburns.
Study shows that eating fish more often is associated with a higher risk of developing melanoma.
Melanoma is the most severe form of skin cancer and causes more than 7,500 deaths yearly in the US. cases are on the rise.
Researchers found that people who ate more fish had a higher chance of developing melanoma. This is the largest and best-designed study to investigate this link. In 1995 and 1996, nearly 500,000 Americans completed a questionnaire about their diets. Participants were on average 61 years old, and 60% of them were men. Over 90% of participants were white, while 4% were Black and 2% were Hispanic.
The researchers tracked how many people got melanoma over the next 15 years and discovered that:
- The rate of melanoma in people who reported eating more fish was 22% higher than those who ate less (about 0.2 servings per week or one serving every five week). Similar trends were observed for tuna intake.
- Similar results were seen in those who ate more fish.
- Researchers found that fried fish had no higher risk of developing melanoma. This is surprising, as frying fish does not eliminate the risk.
Is this a sign that eating fish can cause melanoma?
It doesn’t. It is too early to draw any definitive conclusions regarding the relationship between melanoma and fish in our diets. There were important limitations to the study, such as
- Types of studies – These observational studies can detect a link between diet and cancer, but they cannot prove it.
- Based on self-reported survey data – People reported how many fish they ate each week. This may not have been accurate. Researchers assumed that the 15-year-old fish consumption reported in the initial survey was consistent, but this may not be the case.
- Other factors – There are many factors that can affect melanoma risk, including sun exposure and where people live. Although the analysis did consider some important factors, the study didn’t include information on sun exposure, past sunburns or sunscreen use — all crucial in melanoma risk. Researchers did not ask about skin type and number; melanoma risk is higher in those with fair skin.
- Contaminants – Mercury and arsenic may be responsible for the link to melanoma. Although this study didn’t record contaminants, prior studies have linked mercury exposure to the risk of developing skin cancers including melanoma.
- Inadequacy of diversity – Nine in ten study participants were white.
Is it safer to eat certain fish than others?
This question was not explored in the study. The FDA has advice on what fish are safe to eat for pregnant and breastfeeding women, as well as for those who may be exposed to mercury in fish.
Even if fish is a contributing factor to the risk of developing melanoma from fish, there may be other benefits such as cardiovascular benefit.