A REPORT by Britain鈥檚 Food Standards Agency has raised concerns about the health effects of soya-based infant formula. Although the evidence for harmful effects is not conclusive, it says a handful of recent studies have strengthened the case for avoiding soya formula.
The finding is part of a comprehensive review of the health effects of phytoestrogens. These compounds, found in plants such as soya and lettuce, act in a similar way to the hormone oestrogen. Dietary supplements high in phytoestrogens are also sold in health-food shops.
The report points out that infants fed soya-based formula (about 1 to 2 per cent of babies in Britain) receive higher levels of phytoestrogens than any other group. So any health effects are most likely to show up here. In one study the report looked at, women fed soya formula as babies showed small increases in the duration and discomfort of menstruation. A second study looked at around 8000 boys born in the Avon area. Those born to vegetarian mothers 鈥� who are likely to consume more phytoestrogens 鈥� were five times as likely to have genital abnormalities.
Advertisement
While such studies are far from conclusive, they do tie in with the results of recent experimental work on rodents and marmosets, says Chris Kirk, an expert in phytoestrogens at the University of Birmingham. 鈥淚 think it is right to raise concerns,鈥� he says.
The report calls on Britain鈥檚 Department of 午夜福利1000集合 to review its guidelines on soya-based formula. At present, these state that breast milk is still best 鈥� with cow鈥檚-milk formula second choice 鈥� but soya milk is appropriate where there are medical reasons or parents are vegan. But non-allergenic alternatives to cow鈥檚 milk are now available, leaving mothers who are unable to breastfeed and want their baby to eat a vegan diet as the only people who might want to use soya-based formula.
The main author of the FSA report, Frank Woods of the University of Sheffield, would not be drawn on what the new guidelines should be. 鈥淥ur job was to draw attention to the new data,鈥� he says. But the government鈥檚 Scientific Advisory Committee on Nutrition went further in commenting on a draft of the report. 鈥淲hilst there is clear evidence of potential risk鈥here is neither substantive medical need for soya-based infant formulae nor health benefit arising from their use,鈥� it says.
The report also reviewed the data on supposed health benefits. phytoestrogens have been claimed as remedies for various cancers, osteoporosis, menopausal symptoms and cardiovascular disease. The committee decided the evidence was either absent or contradictory for everything but osteoporosis. And even for that, any benefit was confined to a small region of the spine.
Kirk believes that people are being seduced by the health claims of supplement manufacturers. 鈥淓vidence for these claims is at best very thin and at worse extremely contradictory,鈥� he says.