I hardly kept anything I ate down at all, I puked every day at least 3 times for 8 1/2 months.
What I did eat, but then puked up, was fast food, home cooked food, oatmeal, Braums Chocolate Malts, potato chips, cookies, ice cream, everything looked good and I did not have any knowledge of eating better for the baby.
I think it does not really matter that much unless one is have issues like bulimia or anorexia, there food is not sustaining their own bodies and would not be able to sustain a pregnancy. The body is remarkable. All the nutrients are going to go to the baby first and the mother second so if the mom is eating food, even junk food, it will not really effect the baby that much. Think of all the hundreds of millions of babies that have been born over the life of humanity that did not have our knowledge. Of course they didn't have McDonalds on every corner either.
It won't hurt the pregnant woman to at least try and eat more food that would sustain her AND the baby better.If eating at some place like McDonalds they could chose a Big Mac instead of a Double Quarter Pounder for example. The Big Mac has more bread and more lettuce so it would be less fat. OR, instead of eating at McDonalds eat at Subway and have a 12" ham and cheese sandwich with some lettuce and tomatoes on it. They have lots of healthier choices than most fast food places. These are just examples.