fact sheet six - avoiding cancer

For a long time, scientists have promoted fruits and vegetables to help reduce the risk of heart disease, stroke and some cancers. It is unlikely that any one nutrient or compound in food provides the protection against future disease. It is far more likely that the synergy of many compounds in food combine effectively to offer protection to the body.

It is not surprising that mushrooms have been found to play their part in lowering cancer risk, even though they are neither fruit nor vegetable. Research shows that mushroom extracts reduced breast cancer growth (Chen 2006). “Eating 100 grams, or even less, of mushrooms per day could have an effect on preventing new breast cancers”, said lead researcher Dr Shiuan Chen. Dr Chen has begun human clinical trials and we await the outcome of those trials.

In 2009, research from the University of Western Australia showed that women who ate an average of only 10g of mushrooms a day had a 65% lower risk of breast cancer (Zhang 2009). To date, there have been three international studies linking women who eat mushrooms to a 50-60% lower risk of breast cancer compared to those who do not eat mushrooms (Shin 2010; Hong 2008).

How could mushrooms be helping to protect us? The mushroom contains compounds that suppress two enzymes called aromatase and 5-alpha-reductase. Aromatase converts the hormone androgen to estrogen, which in turn can promote the development of breast cancer, especially in post-menopausal women. Currently, aromatase inhibitors are being used in the treatment of estrogen-dependent breast cancer.

The enzyme 5 alpha reductase converts the hormone testosterone to dihydrotestosterone and is thought to play a role in the development of prostate cancer and benign prostate enlargement in men. The inhibitors of this enzyme reduce the incidence of prostate cancer. The research on animal cells suggest that compounds in mushrooms could have a role in the protection against breast and prostate cancer.

Although it is too early to say that eating mushrooms will stop you from getting breast or prostate cancer, the future looks very promising for the role mushroom could have in reducing the risk of these two common cancers. On-going research is checking to see if mushrooms play a very specific role in protecting against cancer. In the meantime, we can say with confidence that mushrooms are a very useful source of B vitamins, minerals and antioxidant compounds, as discussed in fact sheets #1, #2 and #3.

References:

• Chen S. Anti-cancer activities of white button mushrooms. Mushroom Science XVI 2004: 25-29
• Hong SA, Kim K, Nam SJ, Kong G, Kim MK. A case-control study on the dietary intake of mushrooms and breast cancer risk among Korean women. International Journal of Cancer 2008; 122: 919-923
• Shin A, Kim J, Lim SY, Kim G, Sung MK, Lee ES, Ro J. Dietary mushroom intake and the risk of breast cancer based on hormone receptor status. Nutrition & Cancer 2010; 62 (4): 476-483
• Zhang M, Huang J, Xie X, Holman CDJ. Dietary intakes of mushrooms and green tea combine to reduce the risk of breast cancer in Chinese women. Int J Cancer 2009; 124: 1404-1408

Mushroom & noodle stir-fry
Serves 4

250g dried rice stick or pad thai noodles
400g button mushrooms, halved
1/4 cup kecap manis
2 tbs olive oil
1 red onion, cut into thin wedges
1 red capsicum, quartered, sliced
1 bunch baby bok choy, shredded
125g bean sprouts
1/2 cup dry roasted unsalted peanuts, roughly chopped

1. Place the noodles into a large heatproof bowl. Cover with boiling water. Stand for 5 minutes until just tender. Drain and refresh under cold water.
2. Combine the mushrooms and 2 tbs ketcap manis in a bowl, toss well to coat the mushrooms.
3. Heat a wok over high heat until hot. Add the oil and heat until hot. Add the onion and stir-fry for 1-2 minutes or until tender. Add the mushrooms and stir-fry 2 minutes. Add the capsicum, baby bok choy, noodles and the remaining 1 tbs ketcap manis and stir-fry 1 - 2 minutes or until vegetables are tender.
4. Add bean sprouts and peanuts and toss well to combine. Serve immediately.

Nutritional information:
Mushroom & noodle stir-fry

Protein	17g
Fat	29g
Sat Fat	4g
Carb	22g
kJ	1725
Fibre	8g

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