Scientists make ‘profound’ discovery about diet and cancer as they search for cause of explosion in colon tumors in young people

Scientists studying the explosion of colon cancers among young people say they have made “profound” discoveries about the role played by differences in diet.

Researchers compared and contrasted 176 previous scientific studies to delve into the details of how six popular diets impact the gut microbiome in humans — and which diets lead to increases in gut bacteria linked to tumor growth.

Drawing on nearly two hundred studies, their comprehensive review found that a Western diet high in sugar, saturated fat and processed foods posed the greatest risks.

But the team found that a high-fiber diet used to control blood sugar in diabetics had a protective effect against cancer-related changes.

The study also sparked widespread skepticism about the health benefits of high-protein, ketogenic diets, often popular with health-conscious athletes.

A microbiologist who worked on the new review study called it an “important milestone” that provides “hard data” on the relevance of the microbiome to health.

The Western diet appears to reduce the diversity of bacteria in the gut, leading to an explosion of Bacteroides species linked to obesity.

These foods also left behind a soup of additives and preservatives that these researchers said were linked to a “chronic flare-up of inflammation” in the gut.

A Western diet, low in fiber, fruits and vegetables, also made it harder for the digestive system to break down healthy fiber after eating it, the team found.

People eating a Western diet also had fewer species of bacteria that produce short-chain fatty acids, the researchers said, which may help reduce inflammation in the gut.

Chronic or long-term inflammation of the intestine is of concern because it can lead to damaging mutations in cells, increasing the risk of them becoming cancerous.

Ultra-processed foods — like doughnuts, pizza, and chips — have already been linked to a higher risk of inflammation and associated health risks.

In contrast, those who followed a green Mediterranean diet — rich in fruits, vegetables and olive oil as well as green tea and protein-rich aquatic plants, such as mankai (duckweed) — had the best health outcomes overall.

The researchers said this triggered an increase in “health-promoting bacteria” in the gut and reduced the abundance of those linked to cell damage.

Many of the 176 studies reviewed for the new analysis, published this week in the journal Nature Reviews Microbiology, turned to a bacterial genetic identification technique called “metagenomic sequencing” to study the gut microbiome.

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This method has also been used by ecologists to study the hidden microbial world in nature and to assess the environmental health of polluted post-industrial sites.

Just one of these studies, for example, tracked changes in the gut bacteria of 307 male participants as well as their eating behaviors for six months.

Overall, the scientific reviewers divided this mountain of research into studies covering six different broad categories of diets: the Western diet and the Mediterranean diet, but also high-fiber, high-protein, plant-based and ketogenic diets.

A diet high in fiber, or including plenty of whole grains, is popular among people with chronic constipation or wanting to lose weight.

The study suggested it had a protective effect against colon cancer, type 2 diabetes and inflammation, particularly because it changed the mix of bacteria in the gut microbiome.

It was found that consuming high-fiber plant material led to a “substantial increase” in populations of Lactobacillus And Bifidobacterium bacteria — which release beneficial compounds, such as short-chain fatty acids, that can reduce inflammation.

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A plant-based, or vegetarian, diet has also been shown to reduce the risk of colon cancer because the polyphenols in plants promote the growth of other beneficial bacteria.

The plant-based diet in particular showed an increase in a particular group of bacteria, such as Akkermansiathat help fight bacterial diseases, the researcher wrote.

Researchers have called for more research into the ketogenic diet — or high-fat diet — warning of a history of past studies that show it can cause sudden drops in populations of 19 different species of beneficial bacteria, called Bifidobacteria.

As Akkermansiathese Bifidobacteria They also play a crucial role in “regulating the immune system,” the researchers said, by slowing the growth of infectious bacteria.

But the team also raised concerns about high-protein diets, particularly those high in red meat.

In their study, they noted that the breakdown of meat in the intestine can lead to the release of hydrogen sulfide, which can cause damaging mutations in nearby cells.

“Our study highlights the profound impact of different diets on the gut microbiome,” study lead author Dr. Catherine Stanton said in a statement.

“This understanding is crucial for developing dietary recommendations that promote health and prevent disease,” said Dr Stanton, who works for Teagasc, an Irish public-private organisation that studies food and agriculture.

“It’s fascinating to see how food choices can influence the balance of microorganisms in our gut,” she added, “and their metabolic functions.”

The study comes as researchers struggle to understand the explosion in colon cancer cases among people under 50.

Around 17,000 people under 50 now develop the disease each year, an increase of almost 50% in just two decades, compared with 12,000 cases a year in 1999.

The rate of colon cancer among people aged 20 to 30 increased by about 70 percent during the same period.

Other cancers are also on the rise among young people, including those of the bile duct (in the intestines), breast and appendix.

Kate Middleton, 42, is among the young celebrities to bravely reveal they have cancer this year, while actress Olivia Munn, 43, revealed last year she had breast cancer.

Scientists are puzzled as to what is causing the rise in cancers among young people – and have so far attributed several causes to the increase, from rising obesity rates to regular consumption of processed foods.

Meanwhile, a separate study suggested that an additive used in Red Bull and other energy drinks may promote the growth of cancer cells.

A government-funded team of researchers has launched a $25 million investigation to determine the cause of the spike in March this year.

Colon cancer is particularly concerning because it often does not cause symptoms until it is more advanced, when it is more difficult to treat.

Current guidelines say all Americans over age 45 should be screened for cancer, but some doctors are calling for that age limit to be lowered further.