I spent the majority of my teenage life and early 20s wondering how so many people I knew kept getting diagnosed with cancer. Cancer was just everywhere and it still is. I, like so many other people, thought that cancer was an unexplained mystery in the medical world and that we had no leads on what contributes to it. Then I did a health science degree and I learned that we've actually come really far in learning what increases someone's chance of developing particular cancers and we have a small, yet sound understanding on how to help prevent it.
I feel like it's my role as a nutritional medicine practitioner to share the current research on cancer prevention. No conspiracy theories, no attacking the pharmaceutical companies and no assumptions on what caused someone's cancer. Just cold hard facts on what the current medical research says and what you can do to minimise your risk. Please read this and share it with your friends and family. It is some of the most relevant information you and your family can abide by.
The statistics relating to cancer diagnosis are quite astounding. Please note I am not suggesting that nutritional deficiencies or not getting an 8 hour sleep is why anyone you know got cancer, there are multiple contributing factors, and I am not pretending to be a doctor or an oncologist. I am a clinical nutritional medicine practitioner who has extensively studied and been examined on the effects of nutrients and their lack of on the human body. Whether this plays a small or large part in cancer development and diagnosis I am not certain (the research is mixed). Also dietary effects vary on the type of cancer. For example, the links with diet and colorectal cancer are strong. However, genetics, smoking, alcohol, obesity and inactivity all play a role too.
There are more than 20,000 different phytochemicals (plant compounds) that have been identified in food to have a cancer protective effect. 20,000. Amongst these are mostly antioxidants such as resveratrol and quercetin, sulphur compounds such as indole-3 carbinol and a wide range of vitamins and minerals.
Isothiocyanates, compounds found in cruciferous vegetables such as broccoli, brussels sprouts, cabbage, cauliflower, collards, kale, mustard greens and turnips possess the ability to express genes that are needed to halt tumour progression and are therefore associated with cancer prevention. A meta-analysis published in 2012 found that a high intake of broccoli was linked with a reduction in breast cancer risk. Cruciferous vegetables are also rich in nutrients including carotenoids such as beta-carotene, lutein and zeaxanthin, vitamin C, E, and K, folate and minerals. They are also a good source of fibre too.
Green tea also contains an amazing plant compound called EGCG (epigallocatechin gallate) which activates genes in our body that have the purpose of halting the progression of tumours. This is incredible. Research has shown that regular green tea drinking has a significant and clinically noticeable impact on skin, stomach and lung cancer. EGCG exerts this action through its powerful antioxidant activity.
The skin of an eggplant contains a particular flavonoid called ‘nasunin’, which is a potent antioxidant, meaning it will help protect your cells against damage. But most importantly, nasunin protects the cholesterol in your blood from being a highly reactive toxic form - which in turn may contribute to cancer development. Other foods that contain cancer preventative flavonoids are all purple, red, orange or yellow fruits and vegetables.
Garlic has been shown to contribute to the eradication of cancerous cells. Onions have a similar anticancer profile, where there are actually 30 different plant compounds present in these two foods combined to help reduce tumour growth and prevent cell mutations. One particular study concluded that eating 85g of garlic, onion and other vegetables in their families can significantly reduce stomach cancers.
Fermented, organic soy proteins also contain powerful anticancer properties in the development of breast cancer. These compounds are called isoflavones and they have contributed to protecting large soy eating populations all around the world from increased incidences of breast cancer. Whilst soy is quite an unpopular food choice among many people, the type of soy being consumed makes all the difference. Soy oil, isolated protein and GMO soy flours is absolutely not what we are discussing here. GMO soy can be detrimental to health. However organic, fermented soy products in the form of miso, tempeh and beans have been associated with a protective effect against prostate cancer and breast cancer. I am yet to find any research illustrating its detriment. Most impressively, soy products containing isoflavones consumed by a child have shown reduced risk of breast cancer incidence as an adult.
Whilst the research around processed meats and cancer got a little exaggerated and extrapolated, there is still an association with the preservation of meats by smoking, curing or salting and an increased risk of cancer. This includes ham, bacon, smoked chicken, pastrami and salami. Reducing these foods or educating my clients around their potential impact (mostly because I've found these make up a large part of a lot of my clients diets) is a huge priority for me in clinical practice.
Let’s talk about fibre. I know I’ve focused on this food group a lot recently on my social media but fibre’s one of the most, if not the most important food groups to ensure you are incorporating into every single one of your meals. One of fibre’s most impressive qualities lies in its cancer prevention mechanisms. Fibre has the ability to protect the cancer cells naturally present in our colon and stop them from replicating. FASCINATING.
A folate deficiency (Vitamin B9) has been linked to cancer through its effect on DNA damage. This means that the impact on not having enough of this vitamin in our cells can impair normal cell structure and therefore increase risk of mutant cell replication, i.e cancer. Deficiencies in Vitamin C, E, B2, B6, B12, magnesium, iron and zinc are all risk factors due to this same pathway.
Selenium has been found to be a promising chemopreventive and anticancer agent. Many studies have concluded selenium is hugely indicated in cancer prevention and recently has shown to be useful as a cancer treatment and to halt tumour progression. One particular study demonstrated that selenium can be used as an anti-metastasis (anti-growth and development) agent in breast cancer treatment. Selenium can be found mostly in brazil nuts, organic fatty fish such as salmon and trout, organic eggs, broccoli, cabbage, spinach, mushrooms, beans and brown rice.
Vitamin D is one the most researched cancer protective vitamins. It’s mostly researched in relation to breast cancer and colorectal cancer. The mechanism of action for vitamin D being protective against cancer lies in its ability to help our cells recognise foreign pathogens and activate the pathways we need to fight it.
Curcumin, which is the active compound found in turmeric, is one of the most extensively researched compounds for its cancer preventative qualities. Curcumin is involved in regulating gene expression in various cancer cells and has been shown to possibly inhibit inflammation and carcinogenesis in cancers of the breast, esophagus, stomach, and colon.
Tomatoes also contain an antioxidant called lycopene which has been found to effectively inhibit the growth of cancer cells.
Whilst there is weak evidence on the link between pesticide use from conventional farming and cancer, some small scale studies have linked herbicides with soft tissue sarcoma, non-Hodgkin's lymphoma and leukemia. However, what HAS been studied is the levels of antioxidants and plant compounds in organically farmed fruit and vegetables. They are found in much higher amounts. Therefore, eating organic fruit and vegetables increases your intake of the antioxidants, nutrients, vitamins and minerals that we have discussed here, that are required for preventing cancer growth.
This is just a SMALL PART of what you can include in your diet to help you prevent cancer. There are so many other researched nutrients that have these effects as well as other lifestyle factors that simply cannot be ignored.
But there is a common theme here, and that’s a diet high in fresh fruit and vegetables may help you prevent cancer. We have everything we need in food to help us stop disease forming. Our bodies have healing and repair mechanisms in every. single. organ. Our healing abilities are incredible, but we definitely don’t give them enough credit. We’ve seen all these compounds and nutrients that have actions to help prevent cancer, yet we mostly don’t prioritise getting them into our diet. Some think we have no control over a cancer diagnosis, but now we know we do have some control. Eat well to save your life. It’s very simple, really.
Disclaimer: Cancer is extremely multi-factorial and cannot be put down simply to food. This is merely for educational purposes only to elucidate the link between nutrients and reduced disease risk.