This article is exclusively for Business Insider subscribers, providing insight into a concerning trend: the rise in colon cancer rates among individuals under the age of 50. James Kinross, a gastrointestinal surgeon and researcher at Imperial College London, has delved into this troubling issue, pointing to what he describes as 'an internal climate crisis' affecting individuals in Western nations. He believes this crisis may play a significant role in this alarming increase.

Kinross emphasizes the importance of the gut microbiome, which comprises trillions of microorganisms residing in our digestive systems. These microbes, he explains, have a profound impact on our overall health. 'The gift of the gut microbiome is that you can change it,' he stated, highlighting its adaptability. He believes that through conscious lifestyle changes, individuals can positively influence their gut health and potentially reduce their risk of colon cancer.

Colon cancer stands as the second deadliest form of cancer in the United States, and Kinross has adopted various dietary practices to mitigate his own risk. One of the primary strategies he employs is adhering to a vegetarian diet; however, he acknowledges that diet is merely one aspect of the multifaceted issue of colon cancer risk.

Kinross has pointed out several environmental factors that may have contributed to the degradation of our gut microbiomes. Among these are the consumption of ultra-processed foods, the widespread use of antibiotics—which can disrupt the balance of gut bacteria, the prevalence of microplastics in our environment, and the decreasing exposure to nature. These factors collectively lead to a less diverse microbiome, which in turn, makes it less healthy and resilient.

To illustrate his point, Kinross described a scenario involving a child born via cesarean section. Such a child misses out on crucial microbes that would typically be transferred through the birth canal. If this child’s mother has a gut microbiome compromised by antibiotic use and if the child is then fed a diet predominantly composed of ultra-processed foods, the outcome can be detrimental. 'You’re seeing a generational loss in our internal ecology,' Kinross warned, referring to the cumulative environmental impacts that overwhelm our microbiomes' adaptive capacity.

This imbalance results in what Kinross describes as 'a very unhappy microbiome,' which can produce harmful substances that elevate the risk of colon cancer.

Kinross shared some key dietary recommendations aimed at reducing the risk of colon cancer. One of his foundational tenets is to consume at least 30 grams of fiber daily. 'What I really want in my gut is diversity,' he explained, adding that this can be achieved through a varied diet rich in fiber.

Fiber, abundant in plant-based foods like fruits, vegetables, nuts, seeds, legumes, and whole grains, is linked to numerous health benefits, including a robust immune system. Kinross aims to meet the Food and Drug Administration's daily fiber recommendation by ensuring his meals are colorful and diverse, packed with nutrients.

Moreover, Kinross has adopted a primarily vegetarian diet, partly due to the strong association between the consumption of processed and red meats and colon cancer risk. A significant study published in the International Journal of Epidemiology involving data from approximately 500,000 individuals over seven years concluded that those consuming an average of 79 grams of red or processed meat daily had a 32% increased risk of developing colon cancer compared to those who consumed less than 11 grams.

In 2015, the International Agency for Research on Cancer, part of the World Health Organization, classified processed meats as a 'definite' carcinogen and red meats as 'probably' carcinogenic. Kinross asserts, 'I don’t necessarily believe that we all have to be vegetarian, but I think meat consumption is a big part of our problem,' highlighting the concerning trend of rising colon cancer cases associated with meat consumption.

Another crucial aspect of Kinross’s dietary regimen is the inclusion of fermented foods, which are known to harbor probiotics—beneficial bacteria that support gut health. He strives to incorporate a daily serving of fermented foods such as sauerkraut, kefir, and kombucha into his diet. Research suggests that these foods can enhance the diversity of the gut microbiome. A study conducted by Stanford University in 2021 demonstrated that individuals following a diet high in fermented foods for ten weeks experienced greater microbiome diversity compared to those adhering to a high-fiber diet alone.

Kinross also enjoys sourdough bread and kimchi, the latter being a traditional Korean dish made from fermented cabbage. He shared a personal anecdote about his daughter, who has developed a deep fondness for kimchi, often preparing large quantities at home. This ensures that their household is always stocked with this beneficial food. 'They’ve got to be part of your regular food consumption, otherwise, the microbes just don’t culture and graft into your gut,' Kinross remarked, underscoring the importance of integrating these foods into daily meals.