AR-News: Atkins diet may cut chance of pregnancy, study shows

[jim robertson]

Atkins diet may cut chance of pregnancy, study shows

Sarah Boseley, health editor, in Berlin
Tuesday June 29, 2004
The Guardian

The high-protein Atkins diet may be damaging the chances of weight-conscious 
women getting pregnant and having a healthy baby, scientists said yesterday.
They advised those hoping to conceive to switch to more normal eating 
patterns.

Researchers in Colorado revealed at a European fertility conference that 
embryos from mice that had been fed a high protein diet showed a failure to 
implant in the womb. They believe the results should be a warning to women 
who want children.

"Although our investigations were conducted in mice, our data may have 
implications for diet and reproduction in humans," said David Gardner, 
scientific director of the Colorado Centre for Reproductive Medicine in 
Englewood.

Some 3m people in the UK and 30m in the US are believed to have tried the 
controversial Atkins diet, which advocates high meat, fish and egg 
consumption and severely limited intake of carbohydrates such as bread, 
rice, pasta and starchy vegetables.

Animal research has previously shown that the amount of protein in the diet 
can affect the levels of ammonium in the female reproductive tract of cows 
and mice.

Laboratory tests have also demonstrated that ammonium can interfere with the 
development of mouse embryos. It appears to affect the H19 gene, found on 
chromosome 7, which is important to growth.

The Colorado team fed mice a diet which contained a relatively high 25% 
protein. A con trol group were given a diet which was 14% protein.

People trying to lose weight on the Atkins diet tend to consume around 35% 
protein initially, dropping to 25% later, although Atkins representatives 
say there is no upper limit to the amount of protein that can be consumed.

"We definitely don't set a limit on how much protein people should eat. It's 
as much protein as you need to eat until you are full. Protein is quite 
satisfying so people don't tend to overeat," said a spokeswoman.

In the study, detailed at the European Society of Human Reproduction and 
Embryology conference in Berlin, only a third of the mice (36%) on the high 
protein diet developed with a normal H19 gene, as opposed to 70% of the 
control group.

Of the embryos in the high protein group, only 65% developed into foetuses 
once they had been transferred to the womb, compared with 81% in the control 
group.

"Not only did fewer embryos develop into foetuses when transferred from the 
high protein group, but of all the embryos that implanted, only 84% 
developed further, whereas in the control group 99% of the embryos that 
implanted con tinued to develop," said Dr Gardner.

By the 15th day of gestation, foetuses from the high protein group were a 
third of a day behind the control group in their development.

One foetus had a neural tube defect - damage to that part of the foetus 
which becomes the spinal cord or brain. In humans the defect most commonly 
leads to spina bifida.

"These findings, together with similar work carried out in cows, mean that 
it would be prudent to advise couples who are trying to conceive, either 
naturally or via ART [assisted reproduction technology], to ensure that the 
woman's protein intake is less than 20% of their total energy consumption," 
said Dr Gardner. "The available data certainly indicate that a high protein 
diet is not advisable while trying to conceive."

A spokesman for Atkins Nutritionals Inc cast doubt on the findings. "It is 
important to note that there was no mention of carbohydrate control in the 
research conducted by Dr Gardner," he said. "The study subjects were mice, 
which are herbivores. Whether or not these findings or effects would apply 
to humans, who are omnivores, is unknown."

Ben Gocial, a reproductive endocrinologist from Thomas Jefferson University 
Hospital, speaking on behalf of Atkins, said that controlling carbohydrate 
consumption had been shown to have a positive effect in women who were 
trying to conceive and who were over-weight and/or not ovulating properly.

http://www.guardian.co.uk/uk_news/story/0,3604,1249565,00.html


So many gods, so many creeds,so many paths that wind and wind, while just 
the art of being kind is all this sad world needs.
-- Ella Wheeler Wilcox (1805-1919)