How Many Cancer Cases Are Tied to Unhealthy Diets
Cancer is one of the leading causes of death worldwide. But studies suggest that simple lifestyle changes, such as following a healthy diet, could prevent 30–50% of all cancers (2Trusted Source, 3 Trusted Source).
More than 80,000 cancer cases diagnosed each year in the U.S. may be tied to an unhealthy diet, according to a new study. What’s more, nutrition is thought to play an important role in treating and coping with cancer. This article covers everything you need to know about the link between diet and cancer.
Thought It’s difficult to prove that certain foods cause cancer. However, observational studies have repeatedly indicated that high consumption of certain foods may increase the likelihood of developing cancer.
According to the current study researchers used a mathematical model to estimate the number of U.S. cancer cases tied to suboptimal intake of seven dietary components known to be related to cancer risk. These included diets low in whole grains, dairy, fruits and vegetables; and diets high in processed meats, red meats and sugar-sweetened beverages.
Based on 2015 data, among U.S. adults, an estimated 80,110 new cancer cases, or about 5 percent of total cancer cases diagnosed that year, were tied to a poor diet. That’s on par with the percentage of cancer cases tied to alcohol consumption, which accounts for about 4 to 6 percent of yearly cancer cases, the authors wrote in their study, in the journal JNCI Cancer Spectrum. [What Are Parabens?]
The researchers looked at data from two national surveys on Americans’ diets and, using a computer model, linked this with reported U.S. cancer cases in 2015. The model also included data from the World Cancer Research Fund on the link between, diet and cancer.
Among the seven dietary factors, low whole grain and low dairy intake were linked with the most cancers, followed by high processed meat intake.
“Our results call for nutrition policies to address the U.S. cancer burden” related to diet, for example, by including government-backed, standardized labels for whole grains on foods, and warning labels for processed meats, the authors said.
The researchers note that their model assumed that each dietary factor had an independent effect on cancer risk, and they were not able to account for potential interactions among the dietary factors that may affect cancer risk.
Are Cancer Risks Vary?
Researchers also found disparities among subgroups of the population. Diet-related cancer risks were higher among men, middle-aged adults, and racial as well as ethnic minorities.
Drilling down further, they discovered that colon cancer was the most common type linked to subpar eating habits. Other manifestations of the disease attributable to poor diet, listed in order of new cases, were:
- cancer of the mouth, pharynx, and larynx
- uterine cancer
- breast cancer (postmenopausal)
- kidney cancer
- stomach cancer
- liver cancer.
Mistakes We Make With Our Diet
Looking at which diets were most often associated with new cancer cases, scientists determined they were those that skimped on whole grains, such as oatmeal, brown rice, and bread containing whole-wheat flour.[Danger For Overweight, & Diet Cause For Overweight]
The study’s authors noted that although Americans have been eating more whole-grain foods over the past 14 years, the one daily serving that they were averaging in 2013 to 2014 was still significantly less than the three servings per day the federal dietary guidelines recommend.
Other dietary missteps listed according to the cancer risk they posed from high to low were:
- insufficient intake of dairy products
- eating too much processed meat
- not including enough vegetables and fruits in meals
- overconsumption of red meat
- drinking too many sugar-sweetened beverages
Adults currently eat less than half of the three daily servings of dairy foods endorsed in the 2015–2020 Dietary Guidelines for Americans Trusted Source.
How What You Eat Can Influence Cancer
What you eat can drastically affect many aspects of your health, including your risk of developing chronic diseases like heart disease, diabetes and cancer. [Is Measles Sickness Dangerous To Cancer? Symptoms, Treatment And Vaccination]
The development of cancer, in particular, has been shown to be heavily influenced by your diet. Many foods contain beneficial compounds that could help decrease the growth of cancer. There are also several studies showing that a higher intake of certain foods could be associated with a lower risk of the disease.
Such food include the following, which are:
Sugar and Refined Carbs
Processed foods that are high in sugar and low in fiber and nutrients have been linked to a higher cancer risk (Trusted Source).
In particular, researchers have found that a diet that causes blood glucose levels to spike is associated with an increased risk of several cancers, including stomach, breast and colorectal cancers.
One study in over 47,000 adults found that those who consumed a diet high in refined carbs were almost twice as likely to die from colon cancer than those who ate a diet low in refined carbs. It’s thought that higher levels of blood glucose and insulin are cancer risk factors.
Insulin has been shown to stimulate cell division, supporting the growth and spread of cancer cells and making them more difficult to eliminate.
To protect against cancer, limit or avoid foods that boost insulin levels, such as foods high in sugar and refined carbs.
The International Agency for Research on Cancer (IARC) deems processed meat a carcinogen — something that causes cancer. Processed meat refers to meat that has been treated to preserve flavor by undergoing salting, curing or smoking. It includes hot dogs, ham, bacon, chorizo, salami and some deli meats.
A large review of studies found that people who ate large amounts of processed meat had a 20–50% increased risk of colorectal cancer, compared to those who ate very little or none of this type of food.
Some observational studies have also linked red meat consumption to an increased cancer risk. However, these studies often don’t distinguish between processed meat and unprocessed red meat, which skews results.
Cooking certain foods at high temperatures, such as grilling, frying, sautéing, broiling and barbequing, can produce harmful compounds like heterocyclic amines (HA) and advanced glycation end-products (AGEs).
Certain foods, such as animal foods high in fat and protein, as well as highly processed foods, are most likely to produce these harmful compounds when subjected to high temperatures. These include meat — particularly red meat — certain cheeses, fried eggs, butter, margarine, cream cheese, mayonnaise, oils and nuts.
To minimize cancer risk, avoid burning food and choose gentler cooking methods, especially when cooking meat, such as steaming, stewing or boiling. Marinating food can also help
Several observational studies have indicated that high dairy consumption may increase the risk of prostate cancer.
One study followed almost 4,000 men with prostate cancer. Results showed that high intakes of whole milk increased the risk of disease progression and death. More research is needed to determine possible cause and effect.
Theories suggest that these findings are due to an increased intake of calcium, insulin-like growth factor 1 (IGF-1) or estrogen hormones from pregnant cows — all of which have been weakly linked to prostate cancer.
Foods Containing Cancer-Fighting Properties
There is no single super food that can prevent cancer. Rather, a holistic dietary approach is likely to be most beneficial. Scientists estimate that eating the optimal diet for cancer may reduce your risk by up to 70% and would likely help recovery from cancer as well. However, nutrition is complex, and how effective certain foods are at fighting cancer varies depending on how they’re cultivated, processed, stored and cooked.
Some of the key anti-cancer food groups include:
- Flax seeds
- Beans and Legumes,
Though there are no miracle superfoods that can prevent cancer, some evidence suggests that dietary habits can offer protection.
A diet high in whole foods like fruits, vegetables, whole grains, healthy fats and lean protein may prevent cancer.
Conversely, processed meats, refined carbs, salt and alcohol may increase your risk. Though no diet has been proven to cure cancer, plant-based and keto diets may lower your risk or benefit treatment. Generally, people with cancer are encouraged to follow a healthy, balanced diet to preserve quality of life and support optimal health outcomes.