The total daily calories consumed by people globally, which mainly come from ultra-processed foods, has been continuously increasing in the past two decades
According to the National Cancer Registry Programme India report 2022, the estimated number of incident cases of cancer in India for the year 2022 was found to be 14,61,427 (crude rate:100.4 per 100,000). In India, one in nine people is likely to develop cancer in his/her lifetime. Lung and breast cancers were the leading sites of cancer in males and females, respectively. Among the childhood (0-14 yr) cancers, lymphoid leukaemia (boys: 29.2 per cent and girls: 24.2 per cent) was the leading site. The Indian Council of Medical Research (ICMR) studies predicted that the incidence of cancer cases is estimated to increase by 12.8 per cent in 2025 as compared to 2020.
The report further says that the rise in urban pollution has led to an increased rate of obesity, tobacco and alcohol consumption. As a result, the rate of cancer is growing in India. Lifestyle-related factors are the most important and preventable among environmental exposures. Dietary practices, reproductive and sexual practices, etc. account for a significant percentage of cancers.
A study conducted by researchers at George Washington University found the presence of Phthalates- a compound that helps to make plastic pliable, in 70 per cent of collected samples of junk food. This chemical has been linked with several health problems including being wildly carcinogenic, causing liver damage, infertility, and even asthma. In India, the junk food consumption pattern has been quite significant in the last few years, making the population more prone to the risk of lifestyle diseases and even cancer. In a study conducted in South India, 73 per cent of respondents were regular consumers of fast food, making the population more vulnerable.
“Industrially processed foods are laden with hydrogenated oils, high-fructose corn syrup, artificial sweeteners, flavour enhancers, and thickeners. And consuming such products frequently can considerably raise the chance of developing certain malignancies like cancer. The increased risk of cancer associated with eating processed foods may also be influenced by some food additives and chemical contamination from food packaging. Hence, in order to lower the likelihood of developing such health problems, it’s critical to make an effort to reduce the intake of these processed foods,” said Dr Vivek Srivastav, Senior Vice President, Zeon Lifesciences.
Why junk food should be junked
A new study by researchers at Tufts University and Harvard University found that men who consumed high rates of ultra-processed junk foods were at 29 per cent higher risk for developing colorectal cancer than men who consumed much smaller amounts. Men consuming ultra-processed foods like meat, poultry, or fish-based, ready-to-eat products and also sugar-sweetened beverages, like soda, fruit-based beverages, and sugary milk-based beverages were found to be strongly associated with colorectal cancer. Colorectal cancer — sometimes also called colon cancer or rectal cancer — is the third-leading cause of cancer death in both men and women in the United States, according to the American Cancer Society.
“We started out thinking that colorectal cancer could be cancer most impacted by diet compared to other cancer types,” said Lu Wang, the study’s lead author and a postdoctoral fellow at the Friedman School of Nutrition Science and Policy at Tufts. “Processed meats, most of which fall into the category of ultra-processed foods, are a strong risk factor for colorectal cancer. Ultra-processed foods are also high in added sugars and low in fibre, which contribute to weight gain and obesity, and obesity is an established risk factor for colorectal cancer.”
Moreover, two studies published by the British medical journal found links between high consumption of ultra-processed foods and increased risks of bowel (colorectal) cancer, cardiovascular disease, and death.
Even women were not free from the risk of processed food-driven colorectal cancer. A study led by the Washington University School of Medicine in the US, found a link between consuming sugary drinks and an increased risk of colorectal cancer among women under 50. The researchers calculated a 16 per cent increase in risk for each 8-ounce sugar-sweetened beverage served per day.
Even milk is not safe, if processed
Limiting energy-dense foods, fast foods, and sugary drinks that promote weight gain is a cancer prevention recommendation, but no recent studies have evaluated intake in relation to breast cancer risk. However, according to Marisa C. Weiss, MD, chief medical officer and founder, Breastcancer.org (the world’s most utilised online resource for expert medical and personal information on breast health and breast cancer), although more research is needed to better understand the effect of diet on breast cancer risk, it is clear that calories do count — and fat is a major source of calories. High-fat diets can lead to being overweight or obese, which is a breast cancer risk factor. Overweight women are thought to be at higher risk for breast cancer because the extra fat cells make estrogen, which can cause extra breast cell growth. This extra growth increases the risk of breast cancer.
A study conducted by researchers at Loma Linda University Health, California revealed that even relatively moderate amounts of dairy (milk) consumption can increase women’s risk of breast cancer — up to 80 per cent depending on the amount consumed. In the United States, and in many industrialised countries, raw cow’s milk is processed before it is consumed. During processing, the fat content of the milk is adjusted, and various vitamins are added. The U.S. Dietary Guidelines recommend three cups of milk per day, however, evidence from this study suggested that people should view that recommendation with caution.
The controversy over fibre
Many people commonly consume fibre-enriched foods to promote weight loss and prevent chronic diseases such as diabetes and cancer. Dr Ajaikumar B. Kunnumakkara, Professor, Cancer Biology Laboratory & DBT-AIST International Centre for Translational and Environmental Research, Department of Biosciences and Bioengineering, Indian Institute of Technology (IIT), Guwahati said, “Growing lines of experimental evidence have proved that a diet comprising various bioactive compounds such as polyphenols and carotenoids, vitamin C, and dietary fibres have a beneficial effect on different types of cancers. According to joint research by the World Cancer Research Fund and the American Institute for Cancer Research, a high-fruit and vegetable diet can lower the risk of malignancies of the mouth and throat, esophagus, lung, stomach, colon, and rectum.”
However, researchers from the University of Toledo, US have a different opinion on the fibres. They recently found that diets rich in highly refined fibre like inulin may increase the risk of liver cancer, particularly in individuals who have a vascular deformity in which blood from the intestines bypasses the liver. Fibre is formally classified into two main types, dietary fibre which is found naturally in foods, and functional fibre which is extracted and isolated from whole foods, then added to processed foods. While the researchers did not argue broadly against the health-promoting benefits of fibre, they urged attention on what kind of fibre certain individuals eat, underscoring the importance of personalised nutrition.
Cancer raises an urgent need to develop a dietary intervention to provide treatment and preventive strategies to individuals. Like this dietary fibre controversy, there are many other food ingredients that require a thorough examination and analysis to develop dietary recommendations. An alliance between academia and industry is crucial to achieve this.
Various studies have confirmed that a dietary change could be key to enhancing cancer treatment, especially colorectal cancer. Cancer cells need nutrients to survive and grow. According to the University of Michigan Rogel Cancer Center, when nutrients are limited, cancer cells dial down the nutrient-sensing cascade which leads to massive cell death. Hence this study suggested a low-protein diet for colon cancer.
Likewise, various other nutrients like licorice, curcumin from turmeric, Vitamin D, etc. were found to be beneficial in the prevention and treatment of various types of cancers. Although the studies are small, they provide a strong impetus for research in the field. There is a dire need to initiate global-level studies to unlock the links between various processed foods and cancers. A lack of India-centric efforts and data on this subject is problematic. For developing appropriate dietary recommendation guidelines, such studies are the need of the hour in 2023 and beyond.
Mansi Jamsudkar