We need to shrink the stats.
The numbers are frightening. In 2017, it was estimated that 1 in 2 people will be diagnosed with cancer by their 85th birthday (1-3). That means either Batman or Robin, Bert or Ernie, Bonnie or Clyde, you or me. Perhaps even more horrifying is that as many as 30-35% of cancer-related deaths are linked to diet (4). And that’s not even counting those linked to physical inactivity and stress! We have more control over reducing our risk of cancer than we think.
OnCore Nutrition is passionate about spreading the knowledge to shrink these stats. It’s well established that diets rich in fresh fruit and vegetables, and lower in red and processed meat are protective against cancer. There is also some promising research that gut health can assist with cancer prevention and even unlock some secrets to treatment success (5).
The Bugs: Gut microbiome and cancer
Can the right balance of gut bacteria help us shrink the cancer stats? The research is suggesting maybe it can! Science linking the gut environment with health and chronic disease risk is growing. This includes studies that suggest our microbiota can alter our susceptibility to cancer (6), so listen up…
In 2013, researchers in Michigan found that when they transferred gut bacteria from mice with colon cancer into mice without cancer, the originally cancer-free mice went on to be twice as likely to develop a tumour (7). And it makes sense. When our gut microbiome is out of whack, (i.e. too many Jokers, not enough Batman), the bad bacteria (three specific culprits are E. coli, B. fragiliscan and fusobacteria) release toxins that cause DNA damage and inflammation in the colon which stimulates the growth and spread of cancerous cells(8). These cells not only multiply locoregionally but can spread to other vital organs and tissue. Compare this to a thriving healthy community of Batman-like bugs, which have been shown to reduced inflammation, modulate DNA damage, maintain our gut barrier function, enhance digestion and absorption and produce by-products involved in tumour suppression (6). I know which ones I’d want more of.
The impact of a healthy gut microbiome on cancer development, growth and spread may in some part be linked to the other ‘good fats’ – short-chain fatty acids (SCFAs). When our friendly gut microflora ferment resistant starch and fibre (prebiotics) from our diet, they produce SCFAs. SCFAs have been linked to reduced risk of developing gastrointestinal disorders, cancer and cardiovascular disease (6). The variety and quantity of microflora present in our gut influences the amount of SCFAs we produce and diet is one of the most important determinants of gut microbial diversity. So eat not just for you, but for your Batman bugs too!
Our bugs help in the fight
There is also potential that our microbiota can be manipulated to improve cancer treatment (5,6,9). Recent studies have compared response to immunotherapy treatment for melanoma. The researchers found that people with more diverse gut microbiome were more likely to respond to the immunotherapy treatment (9). We’re now looking more closely into how probiotics can be harnessed to improve cancer care, so watch this space!
Having a healthy gut is vital in ensuring we get the most out of what we eat. Studies have shown that when fed the exact same diet, mice injected with gut microbes from malnourished children didn’t grow as well, had weaker bones and less muscle mass compared to mice injected with gut microbes from healthy children (10). In order to achieve optimal nutrition from our diet, it’s important we keep our gut party pumping!
Probiotic bacteria in our gut feed off prebiotic fibre in our diet. So filling up on plant-based foods that pass through our gastrointestinal tract undigested will provide a banquet for our Batman bugs to feast on. Good sources of prebiotics include the skins and seeds of fruits and vegetables, wholegrains, nuts, seeds and legumes. To add to our hard sell, all of these fibre-rich foods also tend to be rich sources of various phytochemicals (such as isothiocyanates and glucosinolates – the reason why our OnCore dietitian Elise has her broccoli sprout dealer on speed dial!) that exhibit anti-cancer potential (4).
Tailor your plate. Our top tips to get your gut party pumping and reduce your cancer risk!
- Eat a diet rich in vegetables and fruits (and don’t ditch the skin!). Go for 2 fruit and 5 veg per day (a good guide is to fill half your plate with non-starchy veggies at each meal) and eat a rainbow. The prebiotics, antioxidants, micronutrients and phytochemicals will all help to reduce your risk of becoming one of those nasty stats!
- If fruit and veg are your rainbow, nuts and seeds are the pot of gold. Add a small handful of nuts and seeds to your daily routine and always choose wholegrain breads and cereals. The closer they are to their natural state the better. Anyone who wants to talk glycaemic response, insulin-resistance, insulin-like growth factor-1, or just be an anti-carb hater in general, please call me!
- Choose lean proteins, limit red meat to less than 500g per week and don’t forget your omega-3 rich fish (salmon, sardines, trout, herring, flathead, tuna). And if the fins don’t tickle your fancy, talk to a dietitian about taking an omega-3 supplement.
- Chill your grill. Avoid overcooking or charing meats. This process can produce heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs) that can increase cancer risk (11).
- Swap out nitrates, nitrites and other preservatives found in processed foods and deli meats for herbs and spices. Nitrates and nitrites can increase cancer risk. Herbs and spices such as curcumin (turmeric), ginger, cloves, garlic and tea can reduce your risk. Simple.
- Include fermented and probiotic-containing foods such as yoghurt, kefir, kombucha and miso. Pump up your party.
- And last but definitely not least, maintain a healthy weight. Seek the support of an Accredited Practising Dietitian on this one (we know a few good ones if you need some guidance). It can reduce your cancer risk significantly.
Fun fact/Remember: Sustained dietary changes are much more beneficial than short term changes in modulating our cancer risk (5). So don’t just make a change for today, talk to someone who can support you in making a positive change forever.
An exception to the rule
In some cases, during cancer treatment, probiotics and live cultures may not be safe. If your immune function is low, we don’t want to introduce and bacteria (even if they’re good guys) into the body. Make sure you speak to your oncology dietitian to check if probiotics are safe for you.
Tailor your plate. Reduce your cancer risk.
Many cancers have a genetic link. There are many other nutrients and dietary patterns that have shown promise in reducing cancer risk. This will vary for different cancer types. Particular strains of probiotic bacteria have also been linked to reduced risk of specific cancers developing or returning. If you or a loved one are at increased risk of certain cancer through genetics, you could consider speaking to a dietitian specialised in cancer to help build a protective diet to reduce your risk. The oncology nutrition specialists at OnCore are here to help and happy to answer any questions you have. Email us at firstname.lastname@example.org or visit www.oncorenutrition.com.
- Australian Institute of Health and Welfare (AIHW) 2017. Australian Cancer Incidence and Mortality (ACIM) books: All cancers combined. Canberra: AIHW. [Accessed February 2018].
- AIHW 2017. Cancer in Australia 2017. Cancer series no. 101. Cat. No. CAN 100. Canberra: AIHW.
- Anand P, Kunnumakara AB, Sundaram C, Harikumar KB, Tharakan ST, Lai OS et al.Cancer is a Preventable Disease that Requires Major Lifestyle Changes. Pharm Res. 2008 Sep; 25(9): 2097–2116.
- Bhatt AP, Redinbo MR, Bultman SJ. The role of the microbiome in cancer development and therapy. 2017. CA Cancer J Clin 2017;67:326–344.
- Anil R Prasad, Shilpa Prasad, Huy Nguyen, Alexander Facista, Cristy Lewis, Beryl Zaitlin et al. Novel diet-related mouse model of colon cancer parallels human colon cancer. World J Gastrointest Oncol. 2014 Jul 15; 6(7): 225–243.
Schwarzer M, Makki K, Storelli G, Machuca-Gayet I, Srutkova D, Hermanova P et al. Lactobacillus plantarum strain maintains growth of infant mice during chronic undernutrition. Science.19 Feb 2016: