“Until now fathers’ lifestyle choices have not seen any repercussion on their unborn children. This ground-breaking research provides the first definitive evidence that fathers’ drinking habits pre-conception can cause significant fetal abnormalities.”
That was from a press release for a paper in a little known journal called Animals, Cells and Systems. The foetal abnormalities they are referring to are related to the spectrum of mental and physical defects that can develop in a foetus exposed to high levels of alcohol in the womb, known as foetal alcohol spectrum disorders (FASD). Present in an estimated 1 in 100 live births in the US, FASD is believed to be the leading preventable cause of mental retardation in the developed world. That is why women are strongly advised not to drink any alcohol during pregnancy.
But could FASD also be caused by dad’s-to-be drinking pre-conception? A group of Korean researchers set out to investigate this question (1). They took male mice and divided them into five groups. Four of the groups were given different amounts of alcohol, twice a day for 7 weeks, while one group weren’t given any alcohol. After the 7 weeks, they had a week off the booze after which they were placed with females for mating. The resultant foetuses were then examined towards the end of gestation to look for any differences in litter sizes, foetal weights, or for any abnormalities.
Here are the results:
For the low alcohol group (0.5g/kg), 1/8 litters had a foetus with abnormalities (1/120 foetuses = 0.8%)
For the mid alcohol group (1g/kg), 2/5 litters had a foetus with abnormalities (2/65 foetuses = 3%)
For the high alcohol group (4g/kg), 3/4 litters had a foetus with abnormalities (3/63 foetuses = 5%)
The abnormalities were pretty awful – brains growing outside of skulls, swollen brains and missing organs.
What interested me was, how much alcohol were the mice given in human terms? If we work on the basis of an 80kg man, the doses of 0.5g/kg (low) and 4g/kg (high) equate to 40 and 320g of alcohol twice per day for seven weeks, respectively. So how much alcohol is that? I turned to this great website to find out.
It turns out that a standard 330ml can of 4% beer contains approximately 10g of alcohol, as does a 100ml glass of wine. So the ‘low’ dose mice were drinking the equivalent of 8 cans of beer or 8 glasses of wine each day, for 7 weeks. To put this in perspective, the guidelines for men are 3 standard drinks a day and no more than 15 standard drinks a week (preferably with 2 days off a week). At 8 drinks per day, the ‘low’ dose mice were on 56 drinks per week. That’s nearly 4 times the recommended weekly amount.
So what about the ‘high’ dose? According to the website, a 1L bottle of spirits contains approximately 370g of alcohol, while a 3L cask of wine contains 300g alcohol. So the ‘high’ dose mice would be on something like the equivalent of a L bottle of spirits and 3L of wine each day, or 448 drinks per week. That’s nearly 30 times the recommended weekly amount. Imagine the hangover they had after 7 weeks! Actually, I’m very curious to know how the mice behaved while they were exposed to so much alcohol.
So while it certainly may be that dad’s-to-be should join their partners on the wagon while trying to conceive, I don’t think this study deserves the “groundbreaking research” tag trumpeted in the press release.
I chatted to Kathryn Ryan about this story on Radio NZ’s Nine to Noon Programme today, after I enthused about glowing cancer cells.
1. Hye Jeong Lee, Jae-Sung Ryu, Na Young Choi, Yo Seph Park, Yong Il Kim, Dong Wook Han, Kisung Ko, Chan Young Shin, Han Sung Hwang, Kyung-Sun Kang, Kinarm Ko. Transgenerational effects of paternal alcohol exposure in mouse offspring. Animal Cells and Systems, 2013; 17 (6): 429 DOI: 10.1080/19768354.2013.865675