Protein Diet May
Affect Female Fertility
Eating a high protein diet may
make it more difficult for women to conceive, American researchers
Dr David Gardner, of the Colorado
Center for Reproductive Medicine in Englewood, said diets containing
25 percent protein disrupt the development of early mice embryos
and may have a similar impact in humans.
"Although our investigations were
conducted in mice, our data may have implications for diet and
reproduction in humans," Gardner told a fertility meeting.
In mice the high protein diet seems
to interfere with a genetic process known as imprinting, which
controls the activity of genes inherited from the father and mother.
The researchers fed mice a diet
of either 25 percent or 14 percent protein for four weeks before
mating them. Afterwards they examined 42 of the resulting early
embryos, which are known as blastocysts, to see if imprinting
for an important growth gene was altered.
They also transferred 174 early
embryos into the wombs of mice which were eating a normal diet
to study the impact of maternal diet before implantation on fetal
"We found only 36 percent of blastocysts
developed in mothers on the 25 percent diet showed a normal imprinting
pattern, compared to 70 percent in the control group," Gardner
Fewer embryos in the high protein
group developed into fetuses -- 65 percent compared to 81 percent
in the lower protein group.
"These findings, together with
similar work carried out in cows means that it would be prudent
to advise couples who are trying to conceive...to ensure that
the woman's protein intake is less than 20 percent of their total
energy consumption," Gardner told the European Society of Human
Reproduction and Embryology.
"The available data certainly indicate
that a high protein diet is not advisable while trying to conceive,"
But Dr Stuart Trager, the medical
director of Atkins Nutritionals Inc which developed the low-carbohydrate
Atkins Diet, said some studies have shown a positive correlation
between controlling carbohydrates and female fertility.
"The differences between mice and
human embryos have recently been demonstrated by the ability to
produce mice embryos from a single parent, a process that cannot
be replicated in humans," Trager said in a statement.
"This casts a large discrepancy
on the ability to derive conclusions about the clinical implications
of this study with regard to humans," he added.
Reference Source 89