Scary headlines claiming orange juice causes cancer still float around the internet, even though the authors of a 2015 study themselves said their findings were not conclusive.
“Grapefruit and orange juices are breakfast staples for many of us. But consuming these in large amounts may be putting us at higher risk of melanoma – the deadliest form of skin cancer – according to a new study.
… Published in the Journal of Clinical Oncology, the study found people who consumed high amounts of whole grapefruit or orange juice were over a third more likely to develop melanoma, compared with those who consumed low amounts.”
Well, maybe. But as I have pointed out before, correlation does not prove causation.
“Though Dr. Wu and colleagues did not investigate the mechanisms underlying the association between citrus fruit consumption and melanoma risk, they speculate that it may be because the fruits are rich in psoralens and furocoumarins, which are believed to make the skin more sensitive to the sun.” So, just guessing, then.
Let’s suggest another, simpler, possibility. More citrus juices are consumed in places where more citrus is grown. Citrus fruit is almost entirely grown in warmer climates with lots of sunshine. Exposure to sunlight is the predominant cause of melanoma.
I think William of Ockham would prefer my theory.