Cancer is a disease in which some of the body's cells grow uncontrollably and spread to other parts of the body. As cancer becomes increasingly common, myths about it spread quickly - by word of mouth, viral social media posts, and claims from self-proclaimed, non-certified nutritionists or dietitians. This article examines some of the most common myths and aims to provide clearer, science-backed insights.

Common Misconceptions

❌ Verdict: False

You may have heard about alkaline diets for cancer patients, which include water, natural foods, and supplementation. An alkaline diet consists of foods and drinks in the alkaline category, with a pH of 7-14. It is true that incorporating more fruits and vegetables - which are rich in antioxidants and phytonutrients - can benefit your health. However, the body has robust mechanisms to maintain its pH level, largely independent of diet.

Any excess acid or alkali is simply excreted in the urine, with the kidneys playing a key role in keeping pH in balance. Therefore, it is nearly impossible to meaningfully alter the cellular environment within the body by changing your diet. Moreover, while cancer cells cannot survive in an overly alkaline environment, the same is true of normal body cells. The body's normal blood pH falls between 7.35 and 7.45 - straying too far in either direction signals a health problem and can be life-threatening.

There is no study demonstrating a direct relationship between an alkaline diet and cancer prevention.

⚠️ Verdict: Partially True — but misleading

The term "sugar" covers a range of molecules, including the simple sugars found in plants, glucose, and fructose. Carbohydrate sources such as rice, bread, and noodles are broken down into glucose by the digestive system and absorbed by the body for energy. Therefore, all cells - cancerous or not - use glucose, fructose, and other simple sugars for fuel. Because cancer cells tend to grow faster than healthy cells, they have a higher demand for these sugars.

That said, you should limit added sugar, not the natural carbohydrates found in whole foods such as rice, bread, and noodles. Limiting added sugar intake makes sense because excessive consumption can lead to obesity, which increases the risk of at least 13 types of cancer.

Key TakeawayCutting out added sugar is advisable, but eliminating all carbohydrates is unnecessary and not supported by evidence.

✅ Verdict: There is evidence — especially for processed meat

Yes, there is evidence that red meat consumption - especially processed red meat such as pork, beef, lamb, and veal - is linked to a higher risk of cancer. Processed meats such as ham, sausages, frankfurters, bacon, and salami undergo curing, salting, smoking, or the addition of chemical preservatives to extend shelf life or enhance flavour.

Processed meats also contain more nitrites or nitrates than unprocessed meat. These are added to inhibit the growth of Clostridium botulinum and other food-spoiling bacteria. Nitrites and nitrates can convert into nitrosamines, which have carcinogenic properties.

Additionally, when animal proteins are cooked at high temperatures, they produce substances called heterocyclic amines; when grilled or barbecued, they can also produce polycyclic aromatic hydrocarbons - both of which may pose a cancer risk. It is therefore advisable to avoid blackening or overcooking meat. Marinating before cooking can help prevent charring.

Practical TipCancer Council Australia recommends limiting cooked red meat to 65-100g per week. To replace red meat, consider incorporating fish, chicken, or plant-based proteins such as soy, tofu, and tempeh into your meals.

❌ Verdict: False — soy may actually help reduce cancer risk

No. Soy products contain isoflavones, which have been linked to a lower risk of prostate and breast cancer. Isoflavones possess cancer-preventive properties: they lengthen the menstrual cycle, modify estrogen metabolism away from cancer-promoting pathways, and demonstrate anti-proliferative properties in vivo.

Contrary to the claim that isoflavones mimic estrogen and raise cancer risk, they actually act as estrogen regulators. When estrogen is insufficient, isoflavones can carry out its functions; when estrogen is excessive, they block the receptors to which estrogen binds. This estrogen-antagonistic activity helps suppress cancer in the prostate and breast. Isoflavones also inhibit DNA polymerase II, tyrosine protein kinase, and mitogen-activated kinase enzymes, which reduces cell proliferation and promotes apoptosis (programmed cell death).

Examples of Soy ProductsTofu, tempeh, miso, and soy milk are all good sources of isoflavones.

✅ Verdict: Yes — evidence supports its protective effects

Yes. Flaxseed consumption has been shown to reduce the risk and occurrence of colorectal cancer. It is a functional food containing nutrients with antioxidant and/or antitumorigenic properties, including omega-3 fatty acids, lignans, alpha-linolenic acid (ALA), and dietary fibre - all of which help in preventing cancer and cardiovascular disease.

ALA also has anti-inflammatory and antiproliferative effects in animal models of premenopausal (high-estrogen) breast cancer. Increased fibre intake is similarly associated with a reduced risk of breast cancer; a large intervention trial found that high-fibre diets lower the risk of breast cancer recurrence, likely by influencing hormone metabolism and elimination.

How to Use FlaxseedAdd it to baking as a partial substitute for flour, butter, or margarine. Mix it into yogurt or smoothies with fruit. Sprinkle it over salads, overnight oats, oatmeal, fruit parfaits, or homemade granola.

In Conclusion

Many myths circulating in the community about cancer lack scientific support. Before accepting a claim, take the time to understand the mechanism behind it. Always seek information from credentialed healthcare professionals and peer-reviewed research rather than unverified sources.

References

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