There is evidence that regularly drinking scalding hot beverages can increase your risk of developing esophageal cancer.
There is evidence that regularly drinking scalding hot beverages can increase your risk of developing esophageal cancer.
Recent studies have suggested that tattoos, chemical hair straighteners and even hot tea might be a problem. Here’s what an oncologist recommends.
You probably know some of the most common causes of cancer, thanks to the efforts of public health campaigns. In 1964, US Surgeon General Luther Terry issued thefirst report on smoking and health, which concluded that smoking caused lung and throat cancer as well as what’s now known as COPD. After that, programmes to stop smoking are estimated to have saved about 3.4 million people from dying of lung cancer. Similarly, then-Surgeon General Vivek H. Murthy issued an advisory earlier this year on alcohol’s link to certain types of cancer.
There’s clear evidence that smoking and drinking alcohol can increase the risk of cancer, based on extensive data over decades. But you may occasionally see headlines linking other behaviours to cancer, such as getting tattoos and even drinking hot liquids.
Keep in mind that none of these factors has evidence on par with risks like drinking alcohol or smoking. That said, here are five surprising things that have been associated with developing cancer – and what you should know about them.
Two small studies found an association between tattoos and lymphoma. Photo / Lam Yik Fei, The New York Times
Almost one-third of Americans have a tattoo, and 22% have more than one, according to the Pew Research Center. Women and people under 50 are more likely than other people to get inked.
But if you’re debating between a discreet flower near your ankle or a full–sleeve homage to Game of Thrones, you should also know about a recent study.
In an analysis of about 5600 people in Sweden, those with lymphoma were 21% more likely to have received a tattoo in the past compared with those who did not have lymphoma. The size and colour of the tattoo did not appear to make a difference.
A small Danish study of twins also found an association between tattoos and lymphoma as well as between tattoos and skin cancer, possibly because the tattoo ink could make it harder to spot smaller cancers.
But these studies included just a few thousand people and don’t prove that tattoos are a problem. Scientists need to confirm the results in larger studies and with longer follow-up of people who have been inked. Even if the link is true, because lymphoma is a rare cancer diagnosis, affecting just 21 per 100,000 people in the United States yearly, the chances of developing lymphoma from getting a tattoo would be quite small.
Hookah smoking
Smoking hookah might actually be worse for you than smoking cigarettes. Photo / Unsplash
Despite what some people may think, smoking hookah might actually be worse for you than smoking cigarettes: people exposed to hookah tobacco absorb more carbon monoxide than people who smoke cigarettes, because hookah smoking sessions tend to be longer, according to the Food and Drug Administration. They also may absorb more of the toxic chemicals found in smoke. It’s estimated that in an hour-long hookah session, a person inhales 100-200 times more smoke than with a single cigarette.
Hookah tobacco typically contains a mixture of tobacco, sweeteners and flavouring. The device used to smoke it works by passing charcoal- or electric-heated air through the tobacco mixture and ultimately through a water-filled chamber.
In a study of almost 40,000 people living in northern Vietnam, hookah smokers had elevated risks of dying from liver, lung, head and neck, and stomach cancers over a median of 11 years than those who didn’t smoke.
Scientists are confident that tobacco intake is linked to an increased cancer risk. My recommendation: avoid all forms of tobacco, including smoking cigarettes and hookah.
Very hot beverages
In a study from China, more than 450,000 people were followed for a median of about nine years, with 1731 developing cancer of the esophagus. Those who drank burning–hot tea and had at least one alcoholic beverage daily had five times the risk of esophageal cancer, while those who drank burning-hot tea and smoked had twice the risk.
The theory is that drinking scalding hot tea – 140 degrees Fahrenheit (60C) or above – may damage the cells in the esophagus when the tea is consumed multiple times a day for years.
Two studies from the United Kingdom provide more perspective: the first found almost twice the rates of cancer of the esophagus in people who drank 4–6 cups of hot coffee or tea daily. On the flip side, another study from the UK found that tea drinking lowered the risk of death from cancer and cardiovascular or respiratory diseases, potentially implicating the temperature, and not the leaves of the tea, as being the problem.
The evidence for an association between regularly drinking scalding hot beverages and esophageal cancer appears to be consistent across continents, so here’s my advice: it’s reasonable to avoid regular intake of any very hot beverage, though it is more important for you to stop smoking and avoid drinking alcohol.
Chemical hair straighteners and dyes
Chemical hair straighteners and dyes may contain formaldehyde or endocrine-disrupting chemicals which have been associated with hormone-sensitive cancers.
Chemical hair straighteners and dyes may contain formaldehyde – a carcinogen – or endocrine-disrupting chemicals, such as phthalates, which have been associated with hormone-sensitive cancers, including cancers of the breast and ovaries. One study of sisters in 2020 that included more than 46,000 women found that permanent hair dye use was associated with an increased risk of breast cancer, particularly among Black women; while frequent use of straighteners has been linked to a higher risk of breast and ovarian cancer.
A more recent study in the same cohort found that any use of straightening products within the previous year increased the risk of uterine cancer. Using straightening products four or more times led to an even greater increased risk.
Though the data are limited, I suggest reviewing the contents of your chemical hair products before using them, to see if they contain formaldehyde or endocrine-disrupting chemicals.
Meats cooked at high temperatures
When summer approaches, many of us look forward to firing up the grill and having a delicious meal outdoors. But when meat, including beef, poultry, fish or pork, is grilled at high temperatures, it generates carcinogenic chemicals such as heterocyclic amines and polycyclic aromatic hydrocarbons, among others. This occurs as the meat proteins react to the heat and as fat and juice drip onto the fire’s surface, causing flames and smoke.
The evidence that this is a potential problem is stronger here than for some of the other factors on this list. Large population studies suggest that people who consume more meat cooked at a high temperature have a slightly higher chance of developing colorectal cancer.
Because there is strong evidence that red and processed meat is linked to cancer, my advice would be to limit grilling and consuming those in particular. Less grilling is better, and each of us must determine our own tolerance for cancer risk when deciding how often to consumed grilled meats. I limit my own consumption to no more than once per month.
Mikkael A. Sekeres, MD, is the chief of the division of hematology and professor of medicine at the Sylvester Comprehensive Cancer Center, University of Miami. He is author of the books ‘When Blood Breaks Down: Life Lessons from Leukemia’ and ‘Drugs and the FDA: Safety, Efficacy, and the Public’s Trust’.
