Professor Allen said: "There have been sufficient studies clearly showing that when women avoid all animal foods, their babies are born small, they grow very slowly and they are developmentally retarded, possibly permanently."Now I don't know anything about the study but the response by the Vegan Society in the UK, in no way addresses the concerns that the study highlights:
"If you're talking about feeding young children, pregnant women and lactating women, I would go as far as to say it is unethical to withhold these foods [animal source foods] during that period of life."
She was especially critical of parents who imposed a vegan lifestyle on their children, denying them milk, cheese, butter and meat.
"There's absolutely no question that it's unethical for parents to bring up their children as strict vegans," she told the annual meeting of the American Association for the Advancement of Science (AAAS).
In a statement, it said increasing numbers of people were opting for a plant-based diet.Bursting with goodness? What the hell kind of response is that?
Kostana Azmi, the chief executive officer, said: "The vegan diet can provide you with more energy, nutrition, and is bursting with goodness."
She said plant sources were sometimes a safer, and cheaper source of nutrients.
For instance, animal sources of omega-3 oils, needed for the development of the brain and nervous system, were often contaminated with pollutants, such as mercury in fish.
In addition, the vegan diet was often a healthier alternative. She said dairy and meat products were rich in saturated fat, while plant based diets were low in it.
The society does recommend that vegans supplement their diet with vitamin B-12 pills.
The US Agricultural Research Service is part of the US Department of Agriculture.