Whole grains are among the foods that can help to protect against cancer. The regular consumption of three portions per day (roughly 90 g/day) has been found to reduce the risk of colon cancer by 17% for example.
The breast cancer case
Various meta-analyses have recently confirmed the protective role whole grains can play with regard to other types of tumour, including breast cancer. Studies have shown that women following a diet based on the regular consumption of whole grains were at 16% less risk of breast cancer, compared to those women who consumed a very low quantity or none at all. Furthermore, every additional 50 g of whole grains consumed each day was linked to 17% lower risk of breast cancer. This protective action in terms of reducing the risk of illness that whole grains offer can be partly attributed to the presence of fibres and phytoestrogens, principally isoflavones, that modulate the hormonal response, reducing the level of oestrogen circulating, to both inhibit re-absorption by the intestine and facilitate elimination though faeces. Yet a large part of the antitumour action is attributed to the abundant amount of phytochemical substances, mainly phenolic acids, carotenoids, alkylresorcinols (AR), phytosterols, lignans and anthocyanins present in the different types of grains, which have powerful antioxidant, antitumour and anti-inflammatory properties. Various experimental studies have shown that these bio-active components exercise antitumour activity by both modulating the immune system and restricting the proliferation of cells and the progression of cancerous cells, thus obstructing the development of breast cancer metastasis. In other words, the consumption of whole grains can be useful in preventing breast cancer but also in the case of a diagnosis.
How to choose grains
Grains make up a significant class that includes rice, sorghum, millet, naturally gluten free oats, barley, spelt, rye and wheat. Among these, it is the ancient varieties that stand out for their nutritional properties, for example Khorasan wheat, Gentilrosso wheat and Cappelli durum wheat. Various studies have shown us that ancient grains grown organically are much richer in polyphenolic substances and phenolic acids than modern varieties of grain. In addition, we have long known that grains grown using pesticides are a source of exposition to carcinogenic compounds that are found as residues in the end products. One of the compounds we might find as a residue in pasta and flour is glyphosate, a herbicide classified as probably carcinogenic by the International Agency for Research on Cancer (IARC). The impact this herbicide can have on our health is rather worrying, also in terms of the effect it has on the intestine. In fact, a recent study has highlighted how glyphosate is able to reduce certain bacterial species that are known to be beneficial, including Lactobacillus spp., a lactobacillus, and Butyricicoccus spp., an important producer of butyrate, a short-chain fatty acid that has an anti-inflammatory action and is essential for our entire immune system, closely linked to well-being and the balance of the intestinal microbiota.
The cooking of grains
One last interesting fact about grains regards their cooking. If we compare various methods of cooking grains, a significant increase in phenolic, vanillic, syringic and ferulic acids and overall anti-oxidant content is often observed. Whole grains have therefore shown to be a healthy choice, although it is best to favour organic varieties so as to better exploit their potential.
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