Recently I interviewed Cynthia Thurlow, as she discussed the benefits of intermittent fasting, and of course she discussed whether or not it can benefit those with thyroid and autoimmune thyroid conditions. If you would prefer to listen the interview you can access it by Clicking Here.
I am thrilled to chat with Cynthia Thurlow, who is a nurse practitioner and author of the best-selling book Intermittent Fasting Transformation: The IF45 Plan. She is a two-time TedX speaker, with her second talk having more than 10 million views. She is also the host of the Everyday Wellness podcast. With over 20 years of experience in health and wellness, Cynthia is a globally recognized expert in intermittent fasting and women’s health. She has been featured on ABC, FOX 5, KLTA, CW, Medium, Entrepreneur, and The Megan Kelly Show. Her mission is to educate women on the benefits of intermittent fasting and overall holistic health and wellness, so they feel empowered to live their most optimal lives. Thank you so much for joining us, Cynthia.
Cynthia Thurlow:
Thank you for having me. I have been looking forward to our conversation.
Dr. Eric:
Same here. If you could start off by sharing your background and why you are so passionate about intermittent fasting.
Cynthia:
I am a traditionally trained allopathic nurse practitioner. My background as a nurse was in ER medicine. I am a bit of an adrenaline junkie. I trained in inner city Baltimore, so I got to see a lot of amazing things. It was a natural extension to then go into cardiology as a nurse practitioner. I did 16 years of clinical cardiology, both in-patient and out-patient management. I love everything about the heart.
After becoming a parent, I had a child that developed life-threatening food allergies. He had really terrible eczema. Having never really dealt with eczema as an ER nurse, it was really baffling. I kept saying to the pediatrician, because at the time he was exclusively breast-fed, “Do you think it’s something I am eating?” “No, not at all.” His eczema got worse and persisted. We used all the conventional allopathic treatments, like topical steroids, etc. I kept asking, “Is it something that he is eating?”
I finally got a referral to the allergist. Boy, was I surprised to find out that my beautiful, otherwise very healthy two-year-old had life-threatening food allergies. That set me down a proverbial rabbit hole. All of a sudden, I went from thinking of food as being a safe thing to all of a sudden we had to be very careful where we ate. We didn’t eat out much at all to begin with. I got very careful about where we ate in restaurants, ensuring he wasn’t getting cross contamination or exposure of these allergens. It really shifted my focus.
I always say it’s a blessing I had that experience with my son. Thankfully, he is nearly 17 years old and is otherwise very healthy. Only 30% of kids will outgrow their food allergies. He is one of the many children that has not outgrown their food allergy.
I really started looking more deeply. I read a book called The Unhealthy Truth by Robin O’Brien. Then I actually considered doing a doctoral program. I took one class and decided that wasn’t it. I went down another rabbit hole and did a wellness coaching program, which was interesting, but did not light me up. Then I read another book, and I reached out to that author and asked where they got their training.
I think nutrition is what I am most interested in because I was seeing patterns with my patients. Despite the best evidence-based medicine you can imagine, we weren’t curing their cardiovascular disease or diabetes. We were stabilizing symptoms. It was very disheartening. I did this functional nutrition program, and that lit me up. That was the beginning of the end of my traditional path.
Within about a year, even though I was going to work and following those evidence-based guidelines, I became acutely disconnected/frustrated, feeling like we were missing opportunities with our patients. I left clinical cardiology without a business plan. I wouldn’t necessarily recommend anyone do that. Almost instantaneously, I had a large following of women who started coming to me because they felt like their needs weren’t being met. For me personally, during that time period, for a lot of women, as they enter perimenopause, which is the 10-15 years preceding menopause, all the things that used to work no longer work.
For me, the value of the N of 1 was this is someone who had always done everything right. Nutrition, exercise. I thought I was sleeping enough. I thought I was managing my stress. In perimenopause, the game changes. I started having some weight loss resistance. Intermittent fasting to me was something I came to out of an interest to see if I would lose weight. That is how most people are.
What I found was that I didn’t lose weight initially. What I did find is I had more energy. I started sleeping better. I started to feel like I had a very different relationship with food. I could recognize true intrinsic hunger as opposed to “It’s X time. It’s time to eat.” I started with intermittent fasting. Then I started talking to everyone who was willing to listen to me about the strategy, not realizing it would be something I would be known for several years later.
From my perspective, it was traditional allopathic medicine, cardiology, ER medicine. Then pivoting and taking this opportunity.
The other thing that is probably worth sharing is that in 2018, as an introvert, I decided I was going to challenge myself. I was going to do a TED Talk. My husband thought I was nuts. “No, I’m an introvert. This will be a scary challenge.” I didn’t realize I would get multiple offers. I did one talk on perimenopause, that super sexy topic. Around the same time I did my first talk, I was offered a second. That changed everything. Obviously, now I am known for intermittent fasting in women because that talk went viral and really changed a lot of things for me.
Bringing greater awareness to a strategy that is not new or novel, and certainly one that thyroid patients appropriately can integrate into their lifestyle is something that I take as a great honor. I am able to impact more people than I ever would have or could have being just in a hospital or in clinic.
Dr. Eric:
Speaking of thyroid, you have been diagnosed with Hashimoto’s, correct?
Cynthia:
Yes, I have. That is why I like women in particular to understand that you can successfully utilize intermittent fasting and have thyroid disease. As we were talking before we started recording, there is always exceptions. If we really understand that intermittent fasting is not just about weight loss, it actually improves the health of our mitochondria, which are the powerhouses of our cells. From substantive to less substantive, there are lots of benefits. Thyroid patients in particular can benefit from this mitophagy, autophagy, getting rid of these diseased, disordered cells that are no longer serving us.
Dr. Eric:
Can you talk a little bit about metabolic flexibility, what it is? How does it improve when practicing intermittent fasting?
Cynthia:
This is something I have gotten very outspoken about. As you can imagine, in cardiology, I saw a lot of metabolic inflexibility, metabolic syndrome. When we are talking about metabolic flexibility, it is specific to our body’s being able to use both fats and carbohydrates as fuel sources. We don’t want to just be using one over the other. Most individuals, we know based on recent data, it’s 92% of the population here in the United States, is not metabolically flexible or healthy. That is most of us.
How do we actually define what metabolic syndrome is? I look at a couple of variances. We look at waist circumference. This is very important. If people have a waist circumference greater than 35 inches or men greater than 45 inches, that is one.
Another is triglycerides greater than 150. I would advocate it should really be under 75. It’s really a reflection of the quality of carbohydrates someone is consuming.
Looking at HDL. HDL is considered to be “heart healthy cholesterol.” There is more to it than that. In men, we want to see that number greater than 45, and in women, greater than 55.
You also think about fasting glucose. To give you a sense of how long I’ve been practicing, when I graduated from my nurse practitioner program in the early 2000s, you wanted to see blood sugar under 140, which makes me cringe. Now we are saying we want it under 100. I would argue your fasting blood sugar should be under 90, or at least under 95.
When we are looking at these metrics, there are more, like fasting insulin or uric acid. These are all metabolic markers of health. It’s important for you to know these numbers. Some of these things, you can measure at home, like waist circumference. Every year, you should be getting fasting blood sugar, triglycerides, HDL. You should know those numbers, so you can trend and track them.
When we are looking at metabolic inflexibility, these are the people who struggle with weight loss resistance, energy. They will probably get sleepy after meals. They may in fact have poor quality sleep. They won’t have the energy to get up and play with their children or go for a run or engage in sustained exercise. These are individuals who will get hangry. They get this hungry grumpiness that you see in little children because they don’t have the ability to articulate that they are hungry, or they just get grumpy. They also generally tend to gravitate toward foods that are carbohydrate-dense as opposed to protein and healthy fats. These are obviously generalizations.
When we are looking at someone who is metabolically healthy, they won’t deal with weight loss resistance. They are going to be able to go for longer stretches without eating. They will put their meals together differently. They will use protein and carbs or protein and healthy fats.
This is really important for people to understand. I am not anti-carb, but if you are insulin resistant or diabetic, you should absolutely be on some degree of carbohydrate restriction. We can talk more about that.
When I am looking at someone who is metabolically flexible, they sleep well, have plenty of energy, have lots of cognition so they can power through tasks. They don’t think about when their next meal is.
The person who is less metabolically flexible is going to be focused on watching their watch. When is my next meal? I’m hungry. I am running out of gas. I need that candy bar, energy drink, soda in the middle of the afternoon because I get a slump. Those things shouldn’t be happening.
What I think people have forgotten about is that metabolic flexibility is our birthright. It is the way that our bodies are designed to thrive. We have just forgotten. The processed food industry has convinced us as a nation, as a society that we need to eat snacks and mini meals to stoke our metabolism and to have energy. I am here to tell people that eating less often with very few exceptions is the way our bodies are designed to thrive. It is definitely a way to support metabolic flexibility.
Unfortunately, the lay press and magazines like to focus in on this hot new diet system. I remind them that this is our birthright. Intermittent fasting has been incorporated in all major religions. We wouldn’t be here as a species if our bodies had not been able to go through periods of time with food scarcity or even periods of feasting and famine. Metabolic flexibility is something that every single person that is listening should be focused on because our health care system and our nation can no longer support this kind of sick care system that is potentiating and exacerbating metabolic inflexibility.
I will give you an example. Obviously in cardiology, we are dealing with people with disease. They have cardiovascular disease, whether it’s their heart, their brain with strokes, peripherals vascular disease. More often than not, almost all of them have diabetes. Unfortunately, we go about addressing inflammation, oxidative stress, insulin resistance. We wait until someone has disease. We don’t go proactively and say, “Your fasting insulin is abnormal. Your fasting blood sugar and hemoglobin A1C look great. Let’s wait until they look abnormal.” Being more proactive and being truly preventative.
I technically am trained in primary care medicine. I never worked in primary care because at the time, there wasn’t as much of a desire to educate nurse practitioners in acute care medicine. Of course, that makes me laugh because that’s all I did as an NP. The reason why I’m sharing this with your community is that we have to start taking accountability as individuals and as clinicians to be more proactive and not wait until someone is diagnosed with disease. Diabetes takes 10-15 years to be diagnosed.
There is lots of things that start to happen in our bodies, and especially for andropause and menopause and perimenopause. These times we are all going through reverse puberty, there are things we have to be more proactive about in terms of the hormonal changes that are happening in our bodies. It doesn’t mean that you will develop diabetes, but you could become insulin resistant. We want to do everything we can to shift that happening.
We want to be as proactive as possible. This is where the hard work comes in. There is no magic pill. I don’t know if this has been your experience, but I have patients who say, “Give me the pill. I’m not going to change. I’m not going to stop smoking or change my diet or exercise.” I always tell them that’s so disheartening. Yes, lifestyle changes are hard, but the long-term yield is pretty significant.
Dr. Eric:
You mentioned carbohydrates. If someone has insulin resistance, they definitely need to restrict their carbohydrates. If you could talk about if someone has insulin resistance, on average, how many grams of carbohydrates they should be eating? Also, if someone doesn’t have insulin resistance. Like you said, we want to prevent someone from developing insulin resistance. If someone doesn’t have it on a wellness basis, how many grams of carbohydrates should they be consuming?
Cynthia:
Unfortunately, I am sometimes labeled as anti-carb. That couldn’t be further from the truth. I eat lots of carbohydrates: lots of non-starchy vegetables, low glycemic berries. When we are approaching this topic, the first question is are you insulin-sensitive? If you are part of the 8% of the population that is, you probably get a bit more leeway than the rest of the population. What does that look like? On days I earn my carbohydrates, and by that, I mean lift heavy things, I lift at least three days a week.
Every person listening should be doing and incorporating strength training because you have to think of your muscles. Dr. Gabrielle Lyon says they are the organ of longevity. After I started leaning into her work, I started to fully understand and appreciate that she is absolutely correct. Muscles help with insulin sensitivity. We want to maintain lean muscle mass for as long as we can.
Why is this relevant to this discussion about carbohydrates? The more muscle mass you have, the more high quality carbs you can consume. That may look like sweet potatoes, rice (if you tolerate grains). That is the unprocessed stuff. I am not a fan of people eating lots of bread and pasta. I’m sorry to say that. Cookies, candy, that is not the quality carbohydrates I am referring to. But if you are working out hard, and you go to the gym and lift, and you are lean, and you’re insulin sensitive, you can utilize carbohydrates.
I typically recommend that people consume no more than 30-40g in a meal. You have to understand that a candy bar could be 60g of carbohydrates. Just to give you an idea. Really understanding that if you are insulin sensitive, you can very likely get away with 30-40g in a meal. For me, that might be half a sweet potato. We are not talking about a starchy carbohydrate.
When you are insulin-resistant or diabetic, you have to be very mindful. You already have a sugar handling problem. This is where I would say to get your carbohydrates from green, leafy vegetables, low glycemic berries. That doesn’t mean one cup of berries. That means a quarter cup of berries. That means you can have lots of broccoli and cauliflower. Those are good things for your body. That does not mean you sit down with a massive bowl of pasta and have a miniscule amount of protein.
When you have carbs, you never want to have them naked. You should have your carbohydrates with your protein. There is a very interesting book I’m about halfway through by a biochemist called Glucose Revolution. She has some very interesting ways to buffer the net impact of carbohydrate intake. You start with vegetables, then protein, then the carbohydrates. I am very much a fan of pairing your carbohydrates with protein. Never carbohydrates and fat. They generally don’t occur that way in nature, and they are very easy to overeat. Think about chips and guacamole. Let’s be honest. Guacamole is delicious, and salted chips are fantastic, but you won’t trigger the same satiety cues in the body.
To get back to your original question, if you’re insulin-sensitive, you can probably handle 30-40g of carbs in a meal. Always with protein, not by itself.
Another thing people can do irrespective of where they fall on the insulin sensitivity spectrum, and this is well-researched. This is not just me telling you to do this because it’s good exercise. Walking for 5-10 minutes after a meal helps with insulin sensitivity. The organs of longevity are muscles. Your muscles will help with the glucose disposal and insulin sensitivity.
I always encourage people, especially if you have eaten a larger meal than normal that had more carbs than normal, to get out there and take a walk as a way to disperse some of the carbohydrate load that you consumed. A lot of people are thinking, “I eat way more carbohydrates than that in a meal.” You need to examine if you are metabolically healthy, if you are insulin sensitive. Everyone should know what their fasting insulin levels are; they should be between 2-5. If they are higher than that, you have work to do. It may take a bit of time. We don’t become insulin-resistant overnight. I don’t expect that people will become insulin-sensitive overnight. I do think adjusting your carbohydrate intake, lifting weights, taking walks after meals.
Checking your blood sugar. I am a fan of continuous glucose monitors. If that is not in your budget, glucometers can be very beneficial. You can track what your blood sugar response to your meal is. If it’s more than 20-25 points, you probably had too much carbohydrates. Hopefully I’m not busting people’s minds about how we navigate carbohydrate loads. I think a lot of it is dependent on where you are in your life stage, how insulin-sensitive you are, and getting nuance.
I know for myself, I’m 51 years old. I just had a birthday. I am very conscientious about how I time my carbohydrates, when I time my carbohydrates. Always earlier in the day we are more insulin sensitive. I think very thoughtfully about carbohydrates. I probably didn’t when I was younger. Now I definitely am very strategic about when I eat them and how much of them I eat.
Dr. Eric:
I’m glad you mentioned that because a lot of people do the exact opposite. When they have dessert, not that they should be having any bad dessert, but even if they are having a cup of fruit, it sounds like maybe have it early in the day and not after dinner.
Cynthia:
Yes. The other thing to think about is right now, it’s summer. It stays light until 9pm at night where I live. I remind people that in summertime, you can actually get away with a little bit more carbohydrate intake. When I say a little bit, I mean a little bit. I’m not talking about having a brownie sundae at 9pm; that’s a disaster. Maybe you can get away with a little more discretionary- We just got through stone fruit season. I love apricots. It’s one of my favorite things to eat during the summer. They’re not very sweet.
Being mindful of when you eat and what you’re eating. I remind people you really want to be done with eating within 2-3 hours of bedtime. I actually like an earlier stop to my feeding window personally. That is one thing the pandemic showed me. I actually don’t do well eating dinner at 7:30 or 8pm. I do better finishing my meals earlier.
The other thing is this is aligned with current biology, meaning it’s better for us to eat earlier in the day than later. We have these melatonin clocks. We have a centralized clock in our brain called the super chiasmatic nucleus. We also have peripheral clocks in the gut, the pancreas, the liver, and elsewhere. When we eat late at night, it disrupts these clocks. It disrupts melatonin secretion, which impacts our sleep quality, our blood sugar, our cravings the next day.
Getting attuned to your body might be that you have that watermelon or fun summer food that has some fiber in it, the digestion of which will be slowed. Have them earlier in the day. Don’t eat the brownie sundae at 9pm and think you’re doing yourself any favors. My teenagers can get away with that, but my husband and I can’t. Just be mindful of where you are in time and space.
Dr. Eric:
Let’s switch gears and talk about protein. I’m sure just in general there are people who are not getting enough protein. I know some people who do intermittent fasting definitely aren’t getting enough protein. Can we talk more about how people can get enough protein when doing intermittent fasting?
Cynthia:
This is a very important concept. I say this because I inherited co-hosting another podcast. I have one of my own, and I have Intermittent Fasting that I co-host with Melanie Avalon. My predecessor was a big fan of OMAD. OMAD is one meal a day. My biggest criticism, and this is irrespective of gender, is you cannot get enough protein in in one meal a day. I don’t know of anyone that can.
What is enough protein? I say at a minimum 100g a day. For most women, that’s going to blow their minds because they probably are getting 40-50g a day. You heard me mention earlier that muscle is this very important organ. We start to lose muscle mass at a fairly exponential rate after the age of 40. The less muscle mass you have, the less insulin-sensitive you are, the less calories you will actually burn. One of the ways that we circumvent the development of sarcopenia, which is muscle loss with aging, is we have to lift heavy things, eat enough protein, and sleep, amongst a myriad of other things. But those are the three big ones.
I remind women and men that when you are plating your meals, you need at least two food bolus a day. You need to eat at least two good-sized meals a day. I can eat 50-60g of protein in a meal because I have been doing this for a while. In fact, when I was on vacation, I was the person asking for a second portion of protein because I knew I wasn’t going to hit my protein threshold. In Europe, they have small meals. Everything is small, most of which is good, but protein can be a little less than what I’d like.
Maybe you have never tracked your protein intake. Chronometer is a good app. It’s cheap. It’s free in fact. I think it’s very helpful to track your macros for a period of time. Not forever. Not so you feel like you’re being obsessive. But it builds awareness. I find most people are probably doing 25-30g of protein a day. You can’t hit that 100g of protein threshold. Gabrielle Lyon talks about 1g per pound of ideal body weight. I’m 115 pounds. I aim for 115 a day. Sometimes I hit 120. Some days, I hit 90. Over time, it will even itself out.
Protein is not just about maintaining muscle mass. It’s also for satiety. You eat a big enough piece of steak, and you will be full. You won’t be looking at the brownie sundae or more pasta or bread. You’re full. Triggering these satiety cues and switches in our bodies is another really important benefit of protein.
When we are looking at animal-based versus plant-based. I’ll be the first person to tell you that animal-based proteins, the amino acid profiles, are superior to any plant-based protein. For a lot of vegetarians and vegans, they can be very low in protein at the expense of too much carbohydrate. Legumes aren’t a bad thing. Beans aren’t a bad thing.
In order to get the same amount of protein in a plant-based diet, people end up either deficient in protein, or they have completely dysregulated their blood sugar because they are consuming a lot of quinoa, beans, legumes, etc. It’s a careful dance to ensure that people who are predominantly plant-based are getting enough of protein macros.
Protein is very important. In fact, I will often say it is the most important thing you have on your plate. You can technically make carbohydrates from protein through a process called gluconeogenesis. We cannot make our own protein. We have to consume it. We want to consume high-quality, animal-based protein; that’s what I advocate for and speak openly about.
Dr. Eric:
What are your thoughts on protein powders? Obviously, a plant-based protein powder isn’t going to be as good as a hydrolyzed beef one, let’s say. If someone feels like they can’t eat enough protein, is it okay for them to have a smoothie with protein powder with hydrolyzed beef or collagen or maybe even an amino acid supplement?
Cynthia:
Great question. I am a total realist. I am not sitting here on this mountain saying, “I’ve never had protein powder.” I occasionally have a protein bar while I’m traveling. Plus I have teenage boys. The amount of protein they eat is astronomical. If you’re going to consume protein powders, you want to ensure you’re consuming a high-quality product. Something like Marigold, which is whey-based protein. New Zealand, grass-fed, grass-finished cows that you know aren’t being fed a bunch of chemicals. Less ingredients on the label are going to be better than not. I myself don’t tolerate dairy, so I have that one in my house for my kids. I have a bone broth protein.
I think collagen peptides are fine. It’s not a complete protein, but it’s good for hair, skin, and nails. What person isn’t looking to have better hair, skin, and nails, especially as we are getting older?
In terms of plant based, I have talked to some of the leading experts in the field about this. With regard to pea, because that appears to be a very in vogue plant-based protein, we don’t have any research to know what’s going to happen. Does it have estrogenic effects like soy does? We don’t know.
I would recommend if you are doing plant-based proteins that you source from a really high-quality company. Truvani is one that has been recommended. I have tried every protein powder out there to find one that is palatable. I generally don’t find them to be palatable; they are chalky. Truvani is the one I generally recommend if people are looking for a cleaner option, but we don’t know about long-term effects of pea protein.
There is a lot of rice protein that is out there. I always get a little concerned about making sure you have a high-quality product because rice can be heavily arsenic-laden by virtue of where and how it grows.
I am a complete realist. I am all about meeting people where they are. I do have a problem if people are choosing just to have protein bars and shakes and not eating real food. But if you are traveling, on the go, if it’s a busy morning, I get it. You definitely want to put your body through the mechanism of chewing food, swallowing it, having that food bolus hit your stomach because that is much more satiating than a shake or a bar is.
In fact, the hyperpalatability of some of those products, even cleaner-sourced ones, my concern is always if you finish that bar, and you’re thinking about another one, it’s because the processed food industry does a really good job of creating flavor profiles in a way that keeps us wanting more. That’s always the concern.
There are companies out there like Epic as an example that set a reasonable price point. They have a bar that is more like a meat bar. Or Paleo Valley is a company I definitely buy and enjoy their products. Jokingly, that is my protein bar. I take Paleo Valley beef jerky and some salted macadamia nuts, and that is a small meal if I’m on the go. It’s at least clean, and I can live with myself.
To answer your question, I think you want to find the highest-quality supplement with the least amount of ingredients if you go that direction. Things like Perfect Aminos, there is a company out there that has these amino acids. Three years ago, when I was hospitalized for 13 days, I took that product for a while because I could not get enough protein in my diet. My digestive system had gotten so rerouted that I only tolerated protein. Some days, when I was trying to push my protein intake without upsetting my stomach, I would take the aminos, and that worked really well. Again, no affiliation with that company either. Spending some time to think thoughtfully about how to get to that threshold where you are getting at least 100g of protein in a day.
Dr. Eric:
Let’s dive into some of the different intermittent fasting regimens if that’s okay, including of course your IF45 plan. If you could expand on that as well as comparing it to other popular regimens.
Cynthia:
My bulk intermittent fasting transformation, IF45, is a 45-day program focused on a 16/8. 16-hour fast with an eight-hour feeding window. I feel like that is a very approachable window for most people to work up toward. Obviously, there are lots of varieties.
I mentioned OMAD, one meal a day. There are people who do 24-hour fasts. There are people who do longer fasts. There are people who do alternate day fasting. There are individuals who do a combination like a 30/16, meaning they will fast for 30 hours, have a meal, then do a 16-hour fast. A lot of these variations are for different reasons.
I’m at a healthy goal weight. I’m not looking to lose weight, so I don’t do long fasts. After spending 13 days at a hospital and not being able to eat for almost two weeks, that cured me of any desire to go a long period without eating ever again.
I think if you’re metabolically unhealthy, you’re part of that 92%, doing alternate-day fasting, doing longer variations of fasting can be very helpful. If you are diabetic or someone who has high blood pressure or on chronic medications, you want to be having a conversation with your provider to see if you need to be monitoring your blood pressure or sugar more closely. Let me slide that caveat in there.
Typically, the plateau busting comes from variation. Once someone has mastered the basics, then you want to have some variety. Just like we don’t eat the same food every day, like we don’t do the same type of exercise every day, I think our bodies naturally desire to have some flexibility.
Today is a very good example. I broke my fast at 9am because I have a super busy day. I was up early this morning to get the workout in before my day started. I am going to have a wider feeding window today. I have been fasting for a long time. I was also very hungry when I woke up. That was the clue. I have been doing more lifting. I am more hungry.
I don’t believe nor do I recommend anybody white knuckle fast. Meaning if you have a day you’re hungry, if there is a specific time in your cycle, maybe you are lifting heavier, maybe your body needs more macros, more protein, etc., there is nothing wrong with having some variety to your fasting window. But there are a lot of varieties, both time-restricted eating or intermittent fasting and then those longer fasts. Anything over 24 hours is a longer fast.
Dr. Eric:
It’s funny. I was thinking about asking you if you were in a fasting state. I figured we started after 10am. In the back of my mind, I was thinking you were in a fasting state. I’m glad you mentioned that. It’s not like someone has to every single day start at the exact same time, say at 11am and then end at 7pm, depending on how long of a fast you go. You pretty much listen to your body.
Cynthia:
Yeah. Intuitive eating is great. If you’re metabolically flexible. If you’re not, that’s very hard. You go back to the basics. It may take someone who is insulin-resistant six months to get to a point where they are attuned to the cues in their bodies, and that’s okay. I always tell women, “Put your blinders on, and just pay attention to what you’re doing.”
I don’t care how old you are or young you are. We are all influenced by what we see on social media. It’s the extremes. I’m seeing a lot of women in their 50s who are still very lean. Their rhetoric is very different than what I see in a very young 20-ish woman. What happens is people who are in between those age ranges see that, and they are influenced by that behavior. That is why it’s very important that those of us who are in the public eye and have podcasts and are out in the space are very cognizant of the messages we are sending to people our own age and people younger in us about what’s reasonable and attainable versus some stuff- I question if they naturally got to where they are. There is no judgment. We are all influenced by what other people are doing, whether we are aware of it or not.
Dr. Eric:
You mentioned earlier about fasting is not a perfect fit for everyone. Just a few minutes ago, you mentioned you have high blood pressure. Diabetes, you might want to check with your healthcare practitioner.
Let’s get back to thyroid health. Before we started the interview, I mentioned that a lot of listeners have hyperthyroidism or Hashimoto’s. You mentioned your experience with Hashimoto’s. If someone has a thyroid condition, autoimmune thyroid condition, it doesn’t mean they can’t fast. When I dealt with Graves’, I was losing a lot of weight. I lost 42 pounds. I probably wasn’t a good candidate for intermittent fasting then. Now I do incorporate it into my diet. I have been in remission for many years.
If you could expand a little bit more about when you work with thyroid patients, how do you determine who is a good candidate for intermittent fasting? Who might not be a good candidate? Maybe even tie in adrenal health. If someone has compromised adrenals, should that be an indication that maybe they are not ready to fast either?
Cynthia:
Those are good questions. First and foremost, intermittent fasting is a form of hormesis. Hormesis is a beneficial stress in the right amount at the right time. What I see is a lot of men and women desperately want intermittent fasting to be the thing that is going to change it all for them.
If you are newly diagnosed with Graves’, which is hyperthyroidism, or you are newly diagnosed with hypothyroidism/Hashimoto’s, it is not the right time to add more stress to your body. If you were going through a divorce, you were just in the hospital, you are in the midst of a move, you have a lot of stress going on in your life. Don’t add intermittent fasting. It’s not going anywhere. Wait until there is less stress. Your body can’t adequately distinguish intermittent fasting from the divorce or the hospitalization or this stress of a new autoimmune condition.
My standard refrain is if you are stable on medication, which means you haven’t had to have an adjustment, if you wake up and have energy, if you have energy to get through your day, if you’re sleeping, then it is certainly okay to have a conversation with your health care practitioner about whether or not this is the right strategy for you. Now there is enough awareness about fasting that those practitioners are aware of it. They know how to carefully navigate around the strategy.
I do find that there is still a lot of fearmongering about individuals with thyroid disease. I remind people that intermittent fasting can help improve mitochondrial health. We know that if you have an underactive thyroid as an example, your mitochondria aren’t functioning as optimally as they could be, largely because-There is so many reasons why you can become hypothyroid. Is it a nutrient issue? Is it because you have an autoimmune condition? There are so many reasons why you can be hypothyroid.
I think the bulk, somewhere from 80-85% of us with hypothyroidism have Hashimoto’s, even if you have negative antibodies. I want to publicly share that for many years, I was told I did not have Hashimoto’s because I did not have positive antibodies. That probably has everything to do with the fact that I don’t eat gluten and haven’t for over 10 years. More often than not, you have Hashimoto’s until proven otherwise.
With that being said, I do find that intermittent fasting for those with both thyroid health issues and adrenal health issues—adrenal health issues is really your body’s perception of stress. The hypothalamus and pituitary adrenal axis. A lot of what these individuals need to work on is managing stress. That is not five minutes of meditation once a week. It’s getting out in nature. It’s doing things to tap into the parasympathetic, which is the rest and repose side of your brain. It’s sitting down to digest your food. It’s acknowledging that digestion starts in our brains. It goes on and on. The right types of exercise. Doesn’t mean Orange Theory or Cross Fit five days a week. There are many lifestyle things that have to be adjusted before we add in intermittent fasting.
I speak from personal experience that I absolutely have had significant bouts of HPA axis dysregulation. I obviously am thriving with thyroid health issues. I am very stable on medication. My labs are stable. It’s an n of one. Bioindividuality rules. Getting your health care provider involved in the decision-making process. Is this the right time? The answer may be no, but maybe six months from now, you will be ready.
There is no one listening that can’t go 12 hours without eating. No one. Not one person. It’s not going to hurt you. When I walk women through intermittent fasting around their menstrual cycles, I tell them 12 hours of digestive rest, which is exactly what it is, is not going to harm you. Even my teenagers, who eat voluminous amounts of food and are growing like weeds, they can go 12 hours without eating. So can you. Is that technically intermittent fasting? No, but that’s digestive rest, and we all need that anyway.
If you look at the data on meal frequency here in the United States, it’s horrifying. 12 hours of not eating is not going to hurt your adrenals or your thyroid. You want to make sure that you are hooked in with your health care provider, so you can both detemrine when the right time, if at all, is to intermittent fast.
Dr. Eric:
There are so many more things we can cover, but we are running out of time. We may need to do a part two in the future. Everybody needs to dive into your book, which I have also been reading and find fascinating.
For those who are not intermittent fasting and perhaps are thinking about it, or maybe those who are currently intermittent fasting and may look to incorporate your plan, can you give some action steps they should take?
Cynthia:
The first step is to stop snacking. I know that seems trite, but we have been conditioned to believe we need to have snacks and mini meals and eat all day long. The only way you can get from breakfast to lunch and lunch to dinner and dinner to breakfast is to stop snacking because it will force you to restructure your meals. What does that mean? That means you will prioritize protein. You are either having protein and carbs or protein and healthy fats.
The next step is to do that 12 hours of digestive rest and see how you feel. For some people, it may take weeks to get to a point where they have their meals adjusted enough to go from breakfast to lunch and lunch to dinner and dinner to breakfast. That is a very good first step. Once you have mastered 12 hours, you go to 13 hours. Then you go to 13.5. You go to 14.
If you are not fat-adapted, if you are not metabolically flexible, it could take you 6+ weeks or longer. I remind people that if you are metabolically flexible, intermittent fasting is not going to be as challenging. A lot of it can depend on where you are in your menstrual cycle and what life stage you’re in. Those are some very straightforward logical first steps.
If people follow those—stop snacking, restructuring your meals, and doing 12 hours of digestive rest—they generally end up being pretty successful.
Dr. Eric:
Wonderful. Where can people find out more about you? Your website is CynthiaThurlow.com. I’ll let you take over.
Cynthia:
The website is a great place to start. You can catch Everyday Wellness Podcast, which is my solo podcast. I also have Intermittent Fasting Podcast that I co-host with Melanie Avalon. I am active on Instagram. I am a little snarky on Twitter. Depends on the day. I have a free Facebook group called Intermittent Fasting Lifestyle/Cynthia Thurlow, which you are more than welcome to join.
The easiest way to get a sense for who I am and what I’m about is to listen to the podcast. I get to interview really amazing people in the health and wellness space. I have been humbly surprised at how much I love podcasting. It’s one of my favorite things to do. That is probably a great first step if you want to learn more about me.
Follow my crazy dogs. I have teenagers who don’t like to be on social media at all, so out of an abundance of respect for them, you won’t see them much on social media. But I do feature my dogs quite prominently.
Dr. Eric:
Thank you so much for sharing your knowledge. It truly was a pleasure chatting with you.
Cynthia:
Awesome. Thanks so much for having me.
