Interview has been edited for clarity.
According to Dr. Talbert, a plant-based diet is good for female fertility and can particularly help with PCOS, which is one of the most common female fertility issues.
“There was a recent study that proved that people with PCOS who followed this plant-based diet and ate more fruits, vegetables, whole grains, nuts, and seeds increased their chance of becoming pregnant three times versus those who reported not having a diet as healthy and balanced. So it's pretty cool,” says Dr. Talbert.
Dr. Talbert does not recommend it because during pregnancy you need 28 grams of fiber each day for digestion. She says that during pregnancy, your digestion slows. So if you are going to follow the ketogenic diet, you're going to have even more issues with constipation on top of the issues with digestion during pregnancy. And constipation is a common symptom during pregnancy.
Plus, the ketogenic diet may not provide all of the other vitamins and minerals that you need during pregnancy.
“So, for example, you need a good amount of vitamin A in your diet, and you can get that through plant foods. And you need to get a wide variety of antioxidants in your diet when you're pregnant. Think about vitamin C — it would be hard to obtain as much as you need through following the ketogenic diet because the ketogenic diet is more animal-heavy and allows very minimal plant-based foods,” explains Dr. Talbert.
And as for post-delivery, it's not defined, according to Dr. Talbert. “Some say they're following a ketogenic diet, and in my opinion, they're just eating healthy. If they think they're following a ketogenic diet, and they're just eating whole grains and fruits and vegetables, I'm fine with that. But if they were to try to lose the baby weight and follow a very strict low-carbohydrate diet, I wouldn't suggest that long-term because they're definitely going to be deficient in particular vitamins, and specifically they're going to be deficient in fiber.”
Dr. Talbert says that pregnancy can be particularly challenging for people who are underweight with a history of eating disorders, especially if they have body image problems before their pregnancy.
Dr. Talbert encourages people to work closely with a dietitian during their pregnancy to help them focus on the health benefits of eating, help them manage the changes that their body goes through, and remind them that they are growing another person. It's important that they have a whole team to support them mentally and physically during their pregnancy because it may be hard to cope with the changes their body is going through.
“In terms of eating more calories, whenever I'm recommending more calories for weight gain, I'm obviously recommending healthy foods. What I typically suggest for easy quick things is to cook liberally with olive oil. So any time you're eating any dish that is savory, drizzle about a tablespoon or so of olive oil on it once it’s on your plate to add some extra healthy calories,” suggests Dr. Talbert.
Dr. Talbert also recommends being liberal with nuts and seeds when cooking or snacking or to add avocado to your meals/snacks for healthy calories.
With regards to patients who have higher BMIs, Dr. Talbert suggests following more of a plant-based diet. “And it's important to know that when you're pregnant, you actually only need an extra 300 calories a day. And that's the amount in something like yogurt or some fruit. So it's not a lot of extra calories.
If you can start the healthy habits during your pregnancy, it's a lot easier than trying to start them after pregnancy when you have a child that you're taking care of.
“But what happens is, when people get pregnant they have food cravings or certain symptoms that they're trying to manage with food, like headaches or nausea. And it's really important to just try to develop the healthiest habits you can during pregnancy. Because that's only going to benefit you when the baby's born,” Dr. Talbert says.
“When I meet with patients who have a pretty high BMI at the start of their pregnancy, I really focus on this whole plant-based diet. The way that I explain it is that it’s important to take the time now while your baby's inside of you to develop your healthy habits, so then when your baby is with you, you have more energy and better health so you can be with your child and take care of them. It can also help you lose weight, so it’s good for your own health too.
“So if you can start the healthy habits during your pregnancy, it's a lot easier than trying to start them after pregnancy when you have a child that you're taking care of,” Dr. Talbert explains.