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An M.D. On The Plant-Based Ketogenic Fasting Plan She Follows For Health

Liz Moody
Author: Medical reviewer:
Updated on February 4, 2020
Liz Moody
Contributing Food Editor
By Liz Moody
Contributing Food Editor
Liz Moody is a food editor, recipe developer and green smoothie enthusiast. She received her creative writing and psychology degree from The University of California, Berkeley. Moody is the author of two cookbooks: Healthier Together and Glow Pops and the host of the Healthier Together podcast.
Wendie Trubow, M.D., MBA
Medical review by
Wendie Trubow, M.D., MBA
Functional Medicine Gynecologist
Wendie Trubow is a functional medicine gynecologist with almost 10 years of training in the field. She received her M.D. from Tufts University.
Photo by Nadine Greeff
February 4, 2020

One of the most interesting panels at 2017's revitalize was a discussion on intermittent fasting and ketosis, two buzzwords of the health world. Mention a ketogenic diet, and those who are familiar typically picture something similar to a high-fat paleo diet, heavy in animal protein and plant and animal fat.

Because of this, panelist Carrie Diulus, M.D., made waves when she detailed using intermittent fasting and ketosis to maintain an almost 100-pound weight loss and manage her type 1 diabetes. Oh—and she does it all while being plant-based. Fascinated (and filled with questions!), we caught up with her after the panel to learn more.

mbg: Why have you chosen to eat a largely plant-based diet?

CD: I stopped eating meat because I thought it was healthier when I was 12, and I was vegan/vegetarian for about two decades. During my 20s, this resulted in me eating mostly processed junk, which resulted in me weighing 100 pounds more than I do now. I started medical school and lost the weight eating a calorie-restricted, low-fat, mostly vegan diet. During my orthopedic residency, I started eating meat again. I gained 60 pounds with each of my pregnancies and lost the weight (again!) eating low-fat vegan and exercising. My diet at the time wasn't healthy for me; it was super carb-heavy even though I wasn't eating many processed foods. My health declined and I was gaining substantial weight. Eventually, I was diagnosed with type 1 diabetes and started eating a low-carb diet with meat to keep my insulin steady and blood sugar balanced.

This worked nominally well for a while, but I never felt really, really great. Finally, I went back to being vegan but stayed keto. I've never felt better in my life, and my labs look amazing. As a perimenopausal woman in my mid-40s with a history of being morbidly obese and struggling with weight, I couldn't be happier with how good I feel.

mbg: Do you think it's harder for plant-based eaters to achieve ketosis?

CD: I actually find it easier because protein levels are lower in general, and too much protein kicks people out of ketosis. It definitely takes planning, and it's harder to eat out sometimes. At revitalize (where the food was very health-focused—you can see what a day on a plate looked like here!), I sort of picked through the dinner to eat what I could and then went back to my room and ate some of the stuff I had brought. Low-carb diets can be ketogenic or not. Many people do great low carb with higher protein (although the body has a limit with the amount of protein it can process) and moderate fat. A ketogenic diet isn't for everyone, and in fact may be too stressful on the adrenals for some women.

mbg: What do you eat on a typical day when you're trying to maintain ketosis?

CD: I have black coffee for breakfast, and then I have this smoothie starting around 1 or 2 in the afternoon. If I'm not fasting I add sacha inchi or hemp powder to it for protein. At dinner, I will have tempeh, hemp, or hempfu (hemp tofu) as a protein source. I often have natto for vitamin K2. I usually have a bunch of veggies with healthy fats like this cauliflower rice recipe, and I almost always have a salad with olive oil.

I snack on bacu nuts, sacha inchi seeds, macadamia nuts, nori wraps with olive oil and salt, pickles, kimchi, pumpkin seeds, olives, Nuttzo butter or other nut butters, and kale chips. I almost always have some homemade chocolate in the evening.

mbg: Do you think anyone could benefit from ketosis? What types of issues do you use ketosis to address?

CD: I use ketosis in almost all of the patients that I do surgery on, but it is really more of a low-carbohydrate diet than true ketosis. It helps them lose weight, and since a large percentage of my patients have pre-diabetes or diabetes [editor's note: Diulus is a spine surgeon], it helps them to keep their blood sugars managed for surgery, which decreases the risk of surgical complications, like infection or wound-healing problems.

I use true ketogenic diets in patients who have a lot of inflammation. Beta HydroxyButyrate (BHOB) is a strong anti-inflammatory.1 It inhibits COX2, inhibits the NLRP-3 inflammasome, and activates AMPK. This can be really helpful for reducing pain in my patients and has been demonstrated in studies. It is also helpful for neurological conditions. The brain and the nervous system can function very well with ketones. Also, all nerves are surrounded by a membrane that is high in fat. The low-fat movement has led to deficiencies in essential fatty acids and can be problematic related to depression and other neurological conditions.

With regard to blood sugar management, a low-carbohydrate diet can reverse type 2 diabetes and prevent pre-diabetes from progressing. Many people do not need to be in ketosis specifically, but protein does result in the liver releasing glycogen and thus can increase the blood sugar, so some patients need to be more ketogenic (at least temporarily) in order to normalize their metabolism. The receptors on the cell membranes change when the body shifts from burning sugars to burning ketones (for example, MCT-1 receptor in the brain gets activated when ketones are present). C-peptide levels (which are a marker of insulin) also decrease on a low-carbohydrate diet. Type 2 diabetes is mostly a problem of increased insulin in the early phases because of insulin resistance. By eating a low-carbohydrate diet, the high insulin levels go down.

mbg: Do you think it's healthier to be plant-based and in ketosis than to do the meat-heavier ketosis state many people end up doing?

CD: I think there are a small number of people who can thrive on a high intake of animal protein and few vegetables, at least temporarily, but in my clinical experience, a diet like this results in problems down the road, particularly if it is high in processed meats or foods.

If we don't give our patients a plan they can follow, none of the details of it matter. I'm in the Midwest and will sometimes start the conversation with, "Do you like bacon?" and we go from there. My philosophy is to meet people where they are at. In the end, though, my patients end up often eating more vegetables than they have ever eaten in their lives. They start to cut the meat down themselves if they are checking ketones because too much protein makes it hard to stay in ketosis. I find this strategy helps me change the diets of a lot more people than if I was dogmatic about any one program. We also check in with how they are doing and use lab markers. If they are plateaued or struggling with something, we adjust. I emphasize avoiding most of the processed low-carb foods, and if they eat a low-carb processed food, I have them count the total carbs from those foods. For whole natural foods like broccoli, I have them count the net carbs (i.e., total carbs minus fiber).

Ultimately, I recommend my patients to eat 2 cups of non-starchy veggies for lunch and dinner. If they eat a non-starchy veggie, I tell them to put a healthy fat with it, and if they eat a healthy fat, I tell them to put a non-starchy veggie with it.

mbg: You're type 1 diabetic. Every diabetic I've known has been very intense about keeping food on hand at all times in case they have a blood sugar crash—yet you do intermittent fasting. Do you ever get blood sugar dips? If so, how do you deal with them?

CD: Of course, I don't recommend a type 1 diabetic do anything without consulting with their health care team. Fasting is actually sometimes a recommended practice to see if your basal (long-acting) insulin is right. You fast during the day, and if you have low blood sugar, your basal rate is too high and needs to be adjusted lower, either with long-acting insulin or by pump; you should not have low blood sugars. When a type 1 diabetic follows a low-carbohydrate diet, you take much less insulin and have much less likelihood of having high blood sugars related to food. When you use lower doses of insulin because of lower carbohydrate intake, you are less likely to have hypoglycemia. These episodes happen to all of us, but they are much less common and much easier to treat because you don't have a lot of insulin. I can say I have not had a problematic low blood sugar in several years with this approach

Yes, I keep glucose tablets with me. Anyone on insulin should have them on hand at all times. I don’t use food or juice to bring up my blood sugar because it will raise my blood sugar too high above my target, and I am working for small corrections. I will bring my blood sugar up with half or one tablet if I need to raise it a little bit. For people following a higher-carbohydrate diet, much more glucose is needed to correct a low blood sugar.

Since we are talking about ketones and type 1s, we should mention ketoacidosis. There is a difference between nutritional ketosis and ketoacidosis. Ketoacidosis is still possible in a type 1 diabetic, but in a well-formulated diet with normal blood sugars, it is actually incredibly rare and usually is the result of serious illness with dehydration.

One other thing that may also be a factor in it being easier for some in a well-formulated plant-based keto diet to get into ketosis is arginine. Arginine is an amino acid that stimulates insulin release and, in fact, can be used in laboratory testing to see how much the beta cells are still functioning. Foods that are higher in arginine tend to stimulate insulin release, and insulin drives down ketones. There is arginine in plant-based proteins but much less than in animal-based proteins. This is just a theory, but it makes sense in my mind. When we want to see if someone still has beta cells making insulin, we can give them IV glucagon (which makes them sick) or IV arginine (which has fewer side effects).

It might feel intimidating to get started, but start slowly and work your way up. Like with any lifestyle change, it’s important to listen to your body.

And do you want to turn your passion for wellbeing into a fulfilling career? Become a Certified Health Coach! Learn more here.
Liz Moody author page.
Liz Moody
Contributing Food Editor

Liz Moody is an author, blogger and recipe developer living in Brooklyn, New York. She graduated with a creative writing and psychology degree from The University of California, Berkeley. Moody has written two cookbooks: Healthier Together: Recipes for Two—Nourish Your Body, Nourish Your Relationships and Glow Pops: Super-Easy Superfood Recipes to Help You Look and Feel Your Best. She also hosts the Healthier Together Podcast, where she chats with notable chefs, nutritionists, and best-selling authors about their paths to success. Her work has been featured in Vogue, Glamour, Food & Wine & Women’s Health.