1. Ultra-Processed Foods
One of the most popular foods that fill our grocery store shelves and often our pantries are ultra-processed foods, like chips, crackers, cookies, packaged baked goods, etc. They can also include frozen foods, certain 'health' bars, and more.
While these foods are so convenient, as they're sold in abundance, and can certainly be enjoyed in moderation, keeping too many ultra-processed foods in your diet can end up being dangerous, as they can cause certain health conditions that make you more vulnerable to developing cancer.
"They don't typically cause cancer directly," notes Tierney. "Instead, they can contribute to weight gain, chronic inflammation, and lower overall diet quality, all of which can influence cancer risk over time. Enjoying these foods occasionally isn't the issue. The concern is when they make up a large percentage of someone's regular diet."
2. Processed Meats
Some people might not realize just how often they eat processed meats, especially processed red meat. These can range from hot dogs, bacon, deli meats for sandwiches, and more. These products are often convenient, popular at family gatherings, and even eaten as part of people's daily routines. However, they're notorious for being linked to cancer when consumed frequently and in large amounts.
"Processed meats are one of the most strongly linked dietary carcinogens," says board-certified oncology dietitian Alison Tierney with Wholesome LLC. "They're classified as a Group 1 carcinogen by the World Health Organization and the International Agency for Research on Cancer — the same category as tobacco in terms of strength of evidence (not level of risk)."
Tierney notes that these meats often contain "nitrites/nitrates, heme iron, and compounds that are formed during high-heat cooking."
"In the body, these can convert into N-nitroso compounds, which are known carcinogens," she continues.
2. Alcohol
Although alcohol is not a food, it's still a big part of many people's lives, and year by year, it is proven to be very dangerous to our bodies when drunk frequently.
Alcohol is linked to various types of cancer, including breast, colorectal, esophageal, and liver cancer. While a drink here and there in social situations or special occasions won't do as much harm, being a regular drinker and consuming alcohol several times a week can drastically increase your risk.
"Alcohol breaks down into acetaldehyde, a toxic compound that damages DNA," explains Tierney. "It also increases oxidative stress and can alter hormone levels (including estrogen), which is one reason it's linked to breast cancer. For cancer prevention, the WCRF/AICR states that it's best not to drink alcohol. Breast cancer survivors are generally advised to limit intake to three to four drinks per week."