Most young children do not like to eat vegetables and fruits. Partly it could be because their parents do not set an example for them to follow. The lack of emphasis on vegetables and fruits in the menus of fast food outlets like McDonalds and Burger King does not help either. Consuming very little or, worse still, omitting vegetables and fruits from our diet may store up certain health problems in our later life.

Researchers from the Tokyo National Cancer Center studied the relationship of isoflavone intake and the risk of breast cancer (J Clin Oncol 2008; 26: 1677 – 1683). During a mean follow up period of 10.6 years on 24,226 women, aged 40 to 69 years, who were involved in the Japan Public Health Center study, 144 of these women developed breast cancer. The blood level of isoflavone and food frequency questionnaires from these breast cancer patients were compared to those women without cancer. The study showed an inverse relationship between genistein level and breast cancer risk. Individuals with the highest blood level of genistein were 66% less likely to get breast cancer than those with the lowest level of genistein. (Genistein is a type of isoflavone and soya is a rich source of genistein. Other types of isoflavones include daidzein, glycitein, O-desmethylangolensin and equol.)

A Dutch study looked at the blood levels of isoflavones and lignans (enterodiol and enterolactone) in 383 breast cancer women involved in the European Prospective Investigation into Cancer and Nutrition (J Clin Oncol 2007; 25: 648 – 655). The study found an inverse relationship between genistein level and risk of breast cancer. Compared to women with the lowest level of genistein, those with the highest level of genistein were 34% less likely to develop breast cancer. (Isoflavones and lignans are phytoestrogens. These are plant compounds which are structurally and functionally similar to mammalian oestrogens. By competing for the oestrogen receptors, phytoestrogens may well inhibit the binding of the more potent endogenous oestrogens and thus decrease their potential effects on breast cancer risk.)

Examples of foods and herbs rich in isoflavones include bulb onion, garlic, lettuce, cabbage, asparagus, fennel, soy, lima bean, basil, dill and thyme. The best source of genistein is soya bean and soya based food stuff. Soy beans, soy cheese, soy drinks, miso, tempeh and tofu (bean curd) are rich in genistein. Not all types of soy sauce contain genistein; soy sauce made from hydrolysed vegetable protein contains no genistein. So choose your soy sauce well.

It is important to ensure that fruits and vegetables are a regular feature in your child’s daily diet. They contain all sorts of goodies in addition to isoflavones which are necessary for them to grow healthily. Remember the saying ‘An apple a day keeps the doctor away’, it may well be true in more ways than one.

On Friday, the government of Canada announced that it would bring in rules to outlaw plastic polycarbonate baby bottles within the next year. The ban is on bottles made with bisphenol A (BPA), which is also used in making food and water containers. Canada’s action is in response to concerns over BPA’s possible health effects on infants and toddlers since BPA overexposure at an early age has been found, in some studies, to cause behavioural and neurological symptoms in later life. (BPA is also used in the lining of infant formula cans.) While the US government, on Tuesday, said that BPA could be tied to early puberty and prostate and breast cancer, the US Food and Drug Administration considers BPA safe for use by infants and children.

The National Centre for Environmental Health assessed the exposure of the US population to BPA and 4-tertiary-octylphenol (tOP), both chemicals used in the manufacture of polycarbonate plastics, epoxy resins and nonionic surfactants (Environ Health Perspect 2008; 116: 39 – 44). They measured the total urinary concentrations of BPA and tOP in 2,517 participants, aged ≥ 6 years, in the 2003 – 2004 National Health and Nutrition Examination Survey. The study showed that, compared to males, females had more BPA in their bodies. Children had the highest concentrations of BPA when compared to adolescents and adults. The BPA concentration in adolescents was still higher than in adults.

In the body, vascular endothelial growth factor (VEGF) is an important molecule that promotes angiogenesis (growth of new blood vessels) and tumour growth. In animal studies, it has been shown that VEGF increases capillary permeability (leakiness of the small blood vessels) and breast tumour angiogenesis. The VEGF gene is regulated by the hormone estrogen. BPA is a type of xenoestrogen and a group of French researchers studied the effect of BPA on 2 types of breast cancer cells with estrogen receptors on their surface (J Endocrinol 2008; 196: 399 – 412). The study showed that BPA increased VEGF secretion by these cancer cells.

Researchers from Ege University in Turkey, studied the effects of BPA on the embryos and sperm of the sea urchin (Paracentrotus lividus). BPA caused a reduction in the rate of successful fertilization and increased the incidence of skeleton malformations in the embryos (Environ Toxicol 2008 Jan 23, epub). A study from Fox Chase Cancer Centre examined the effect of BPA on mammary gland (breast) morphology in young female rats born to mothers who were exposed to BPA during pregnancy (J Endocrinol 2008; 196: 101 -112). BPA exposure resulted in breast architectural modifications, mainly in the number of undifferentiated epithelial structures in the breast tissue and in up-regulation of genes related to the immune system. The architectural modifications and genetic up-regulation suggest that BPA exposure during pregnancy can affect the susceptibility of the breast tissue to transformation in the newborns.

Major Canadian retail chains have already started removing bottles and containers made with BPA because of public concerns. The US company, Nalgene, a major producer of baby bottles, announced last Friday it would phase out the use of BPA despite the FDA’s assertion that BPA is safe. Life is full of risks and we have to make choices on whether to take that risk or not. Sometimes, we have to make a decision not based on absolute certainty because if we wait for confirmation, many may have been affected. It is better to be safe than to be sorry.

French researchers just published their studies examining the association between serum phospholipid fatty acids and breast cancer among women in the E3N Study (1989 – 2002). (Serum phospholipid fatty acids are biomarkers of fatty acid intake in an individual and the E3N Study is the French component of the European Prospective Investigation into Cancer and Nutrition.) The study involved 19,934 women who had completed a diet history questionnaire and provided serum samples at the start of the study (1995 – 1998). During an average of 7 years of follow-up, 363 cases of invasive breast cancer were found in these 19,934 women (Am J Epidemiol 2008 Apr 4, epub ahead of print). The study found that, as the blood levels of the trans-monounsaturated fatty acids palmitoleic and elaidic acid increased, the risk of developing breast cancer increased. Comparing women with lowest to women with highest levels of trans-monounsatuarted fatty acids, the women with the highest levels were 75% more likely to develop breast cancer. The researchers concluded that ‘A high serum level of trans-monounsaturated fatty acids, presumably reflecting a high intake of industrially processed foods, is probably one factor contributing to increased risk of invasive breast cancer in women.’

trans Fatty acids (TFAs) are unsaturated fats with at least one double bond in the trans configuration. They are formed during the industrial hydrogenation of vegetable oils. In simpler terms, trans fats are made when manufacturers add hydrogen molecules to vegetable oils. TFAs are primarily used in fast foods, bakery products, packaged snacks and margarines. Humans cannot manufacture TFAs and thus all TFAs in the body are from the diet.

The potential health hazards of consuming TFAs was raised in 1993 when Willett and his co-workers of Harvard Medical School published an article in the prestigious medical journal, The Lancet (Lancet 1993; 341: 581 – 585). In it they reported that women who regularly consumed margarine as part of their diet had a significantly increased risk of coronary heart disease (CHD). The risk of CHD was increased by 67%.

Not all eating establishments worldwide have adopted the policy of not using TFAs in their cooking. While some fast food eateries have switched from using TFAs, not all have changed citing the reasons ‘not using TFAs will drive up manufacturing cost and the food will taste less palatable’. However, this argument does not hold water because the Danes have shown the world, many years ago, that this can be achieved without compromising on the taste of the food and without escalating the cost of the manufactured food.

CHD and breast cancer are two serious health problems worldwide. The cost of treating these two conditions will cost far more than the cost of using an acceptable substitute to TFAs in making fast foods, bakery products and packaged snacks. With time, perhaps more health problems may be discovered to be linked to consuming TFAs. I think it is prudent for society to drastically curtail the use of TFAs in order to reduce the societal burden in treating TFA-related health problems.