"Some people subscribe to the myth, 'I'm eating for two people,' " Parks tells PEOPLE.
"Well, not really. The other person is half of a pound. I wouldn't really count that as an individual. It's obviously a living organism, but something weighing 7 lbs. doesn't really allow you to eat two meals. Doctors say you only need an additional 500 calories."
Parks – who already has a son Ayden, 2, with her husband Apollo Nida – doesn't find it difficult to remain a healthy weight while pregnant.
"I don't count calories," she says. "I just try to eat organic, healthy food. I eat a lot of small meals per day. If I want something, I try to eat it in moderation if it's something that's not good for me. I don't really have any cravings. The only thing I [craved] during my last pregnancy were oranges. I love citrus fruit."
Adds Parks, "I really have little or no time to ponder about food all day. I just eat to live. I don't live to eat. Some people are living to eat, and I try to have a healthy relationship with food."
Nutrition habits aside, Parks – who recently released a new exercise video, Phine Body: Volume 2, on Jan. 31 – stays in shape with a rigorous fitness routine.
"Now I'm really doing a lot of water aerobics and stretching," she explains. "When you're pregnant, everything's moving and shifting and you've got aches and pains that you never even knew of."
The new video, she says, "focuses on arms, chest area, the entire body. It's a little more challenging than the first one, but it's still anaerobic. You're going against your own body weight and you're only using household products – milk jugs, cans of green beans, things that everyone has in the house. We try to make it easy for everyone."
Once baby is born, Parks strongly advises breastfeeding for getting a woman's body back post-pregnancy.
"I tell people to nurse their baby," she says. "It tightens up your uterus. It brings everything back in places very quickly. And it cuts down on buying milk and going to the grocery store. Milk does a body good, and if you can make it yourself, then why not?"