The RSA responded that it was not fair to compare the impact of a big meal to the impact of alcohol
Danny Healy-Rae has claimed that people can be a danger on the road if they "eat too much".
The Kerry TD was speaking at an Oireachtas committee earlier today, where representatives of the RSA were discussing proposed new drink driving legislation.
The proposals include an automatic driving ban for first-time offenders caught at the lower limit.
Addressing the RSA representatives, Deputy Healy-Rae called for more detailed statistics of road deaths where alcohol was a contributing factor.
He went on to claim: "Many people will agree with me - if you actually eat too much, and get in behind the wheel of a car, you're a danger on the road because you're liable to fall asleep after eating a big meal.
"I for one when anyway, when I'm going home out of here this evening, when I know that I won't eat going in behind the wheel because I know what it will do. There could have been many other overriding reasons and causes of the accident, as well as the consumption of a small amount of alcohol.
Velma Burns, research manager with the Road Safety Authority (RSA), disputed the claims.
She said: "I disagree that there are other overriding factors, because the research shows that when alcohol is consumed and driving, that leads to other risky behaviours. The alcohol consumption comes first.
"I don't think it's a fair comparison to talk about the impact of a big meal on driving compared to the impact of alcohol."
Earlier, Moyagh Murdock - the chief executive of the RSA - lashed out at vintners over their opposition to the proposed legislation.