Hard on the heels of impressive research findings that a glass of milk is good for reducing cancer risk , another recent study has highlighted the potential benefits of yoghurt consumption in lowering the risk of certain types of cancer - particularly colorectal cancer.
Author
- Justin Stebbing
Professor of Biomedical Sciences, Anglia Ruskin University
The number of new colorectal cancer cases among people under 55 has doubled globally in recent years , with diagnoses increasing by nearly 20%. As a consultant oncologist, many people have asked me how their risk can be reduced.
The emerging evidence suggests that regular yoghurt consumption may have a protective effect against certain aggressive forms of colorectal cancer by modifying the gut microbiome , the natural bacteria that live in the gut.
The gut microbiome plays a crucial role in overall health, influencing digestion, immune function and even cancer risk. The gut bacteria can live inside cancer itself, and in general a healthy balance of these bacteria is thought to be essential for maintaining a strong immune system and preventing inflammation, which can contribute to cancer development .
Yoghurt contains live cultures of beneficial bacteria, such as lactobacillus bulgaricus and streptococcus thermophilus , which can help maintain this balance.
The study found that consuming two or more servings of yoghurt per week was associated with a lower risk of a specific type of aggressive colorectal cancer, which occurs on the right side of the colon and is associated with poorer survival outcomes compared with cancers on the left side.
The study analysed data from over 150,000 participants followed for several decades, indicating that long-term yoghurt consumption may alter the gut microbiome in ways that protect against certain cancers. Researchers surveyed the participants every two years about their yoghurt intake, and measured the amount of Bifidobacterium ( a type of bacteria found in yoghurt ) in the tumour tissue of 3,079 people within the sample who were diagnosed with colorectal cancer.
While yoghurt did not directly lower the risk for all types of colorectal cancer, those who ate two or more servings of yoghurt per week had a lower risk of developing "Bifidobacterium-positive proximal colon cancer" , a type of colorectal cancer that occurs in the right side of the colon and has one of the lowest survival rates. This new work also validates and builds on previous studies showing similar findings.
Several mechanisms have been proposed to explain how yoghurt might reduce cancer risk. One key mechanism is the modulation of the gut microbiome . Yoghurt's probiotics can enhance the diversity and balance of gut bacteria, potentially reducing inflammation and levels of cancer-causing chemicals ( carcinogens ).
Additionally, yoghurt may exert anti-inflammatory effects on the colon lining cells, called the mucosa , which could help prevent cancer development. Improving gut barrier function is another potential mechanism, as yoghurt may reduce gut permeability , which is linked to increased cancer risk.
Choose wisely
Beyond its potential anti-cancer effects, yoghurt offers several other health benefits. Like milk, it is rich in calcium, which supports bone density and may reduce the risk of brittle bones, known as osteoporosis.
Regular yoghurt consumption has also been associated with lower blood pressure and reduced risk of cardiovascular disease . Some studies suggest that yoghurt intake may help prevent type 2 diabetes and other diseases too.
But when incorporating yoghurt into your diet, it's important to choose wisely. Opt for plain, unflavoured yoghurt to avoid added sugars, which can negate health benefits - for example by causing weight gain, which is a risk factor for obesity and cancer.
Different fermentation processes can result in varying levels of beneficial bacteria, so look for yoghurts with live cultures . Plain, unsweetened Greek yoghurt is generally higher in protein and lower in sugar, while full-fat yoghurt often has fewer processed ingredients than reduced-fat or non-fat variations.
Yoghurt contains all nine essential amino acids, and aside from improving gut health, a serving of plain Greek yoghurt contains 15 to 20 grams of protein .
There are nearly 45,000 cases of bowel cancer every year in the UK, making it the nation's fourth most common cancer, and third worldwide - but many of these are preventable .
According to Cancer Research UK data , 54% of all bowel cancers could be prevented by having a healthier lifestyle. Smoking, lack of exercise, alcohol, eating processed meat, and poor diet are all significant factors in the development of bowel cancer.
The emerging evidence suggests that yoghurt, particularly when consumed regularly, may play a role in reducing the risk of certain aggressive forms of colorectal cancer. While more research is needed to fully understand these effects, incorporating yoghurt into a balanced diet could be a beneficial choice for overall health.
But as with any dietary recommendation, it's crucial to consider the broader context of a healthy lifestyle, including a diverse diet rich in fruits, vegetables and whole grains, along with regular physical activity. While yoghurt is not a magic bullet against cancer, it is a nutritious food that can contribute to a healthy diet and potentially offer protective effects against certain cancers.
As research continues to uncover the complex relationships between diet, gut health and cancer risk, incorporating yoghurt into your daily routine may be a simple yet beneficial step towards a healthier life.
Justin Stebbing does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
