There are a lot of opinions on nutrition during pregnancy, there are also a lot of legitimate facts. Fast food and junk food seem to be pretty common cravings while going through a pregnancy, but how safe is giving into all these cravings? It's obvious that occasionally giving in to a junk food craving won't hurt, but will giving in to every craving cause you any harm?

There was a study that was conducted that showed rats who ate a heavy fat, sweet diet while pregnant gave birth to heavier babies who had a preference for fatty and sweeter foods that lasted all the way into adulthood. Humans aren't rats, but it did show that eating too much junk food could wire the baby's brain in a way that made them prone to eating junk instead of a healthy, balanced diet.

Another study found that giving in and eating too high a fatty, sugary diet while pregnant actually changed baby's genes making them more prone to obesity, heart disease, diabetes type 2 and junk food addiction. It showed in a lab rat study for three generations.

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It's recommended to avoid junk food altogether when you're pregnant, everything you eat is passed to the fetus, and the additional 300 calories needed can be made up by adding healthy fats like avocados or even peanut butter. It's not always easy to ignore a craving, so it's recommended to stick to limiting junk food to 1-2 times a week or less.

There have also been findings that avoiding junk food in later pregnancy is more important than earlier. Later seems to do more damage than if you caved to your craving earlier on. In a way, you can kind of make up for caving early on by avoiding fully in the last trimester.

But what actually is "junk food"? Junk food, in the instance of the advice given means high fat, high sugar, overly processed and most fast foods. Fast food may be convenient, but the servings are so large and calorie dense, it gives more calories than needed with many more fillers, additives, sugar, and transfat.

Fast food may be the "best" go-to option, but if you pay close attention to how many calories and the nutritional value of your meal, even your salad, you'll see how many empty calories and how much excess is involved. The best option is to take the free time you have, days off work or times your significant other is home, to batch cook and freeze individual meals. When you batch cook, you end up with enough to last a few meals at least and if you freeze individual portions, you can heat it fast like a microwave meal.