HSOS #11: Intermittent Fasting After 40: What You Really Need to Know

October means Halloween candy season—and Kim kicks things off with a confession about her Costco-sized candy stash and the tricks she uses to keep it out of sight until trick-or-treat night. From there, she dives into the question she hears most: should women over 40 be doing intermittent fasting? Kim explains what it actually is (no, it’s not magic), what the research really shows, and why it often ends up feeling like another quick-fix diet. She shares the sneaky downsides, who should skip it, and offers a saner, more sustainable way to support your metabolism that doesn’t involve rigid fasting rules.

Let’s talk.

Welcome to Her Season of Strength—where women over 40 reclaim their bodies, their energy, and their voices, without apologies. I'm Kim Duffy—registered dietitian, personal trainer, mom, and your biggest hype woman when it comes to aging like you mean it.

This show isn’t about chasing skinny or counting wrinkles. It’s about building real strength—physical, emotional, and hormonal. Each week, I’ll share straight-talking nutrition tips, sustainable fitness strategies, and conversations that help you feel powerful in your skin once again.

Menopause is not an ending, it is only the beginning. This is your season of strength.

🎙 Key Points in This Episode

• Halloween candy and why Kim hides hers until the last minute
• Client questions about intermittent fasting—why it’s such a hot topic
• The basics: 16:8, 5:2, and alternate-day fasting explained
• Research shows modest weight loss, similar to calorie reduction
• Possible benefits: simple rules, less nighttime snacking, appetite control
• Risks: low energy for workouts, harder to hit protein needs, sleep issues
• Food preoccupation and overeating once the window opens
• Who should avoid fasting: eating disorder history, pregnancy, meds, underweight
• Why it’s often just another quick-fix that slows metabolism
• A better path: after-dinner kitchen close, protein-forward meals, strength training, sleep
• Grab the one page cheat sheet➡️ "The Truth About Intermittent Fasting for Women 40+"

Quick listener ask

If this helped, a rating or review makes a huge difference. Share it with a friend who’s curious about intermittent fasting, or message me and tell me your Halloween candy strategy—I’m all ears!

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Free cheat sheet: "20 Tips to Crushing Menopause"

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Transcript

[00:00:00] Hi there, and welcome to her season of Strength, where women over 40 reclaim their bodies, their energy, and their voices, without apologies. I'm Kim Duffy, registered dietician, personal trainer, mom, and your biggest hype woman. When it comes to aging like you mean it, this show isn't about chasing skinny or counting wrinkles.

[00:00:20] It's about building real strength, physical, emotional, and hormonal. Each week, I'll share straight talking, nutrition tips, sustainable fitness strategies. And conversations that help you feel powerful in your skin. Once again, menopause isn't an ending. It's only the beginning. This is your season of strength.

[00:00:39] Hello. Hello. Welcome back to her season of Strength. I am so happy you're here and thank you for taking just a couple minutes outta your day to listen in. So it is officially October now and it is Halloween month. And I don't know about you, but like I have a hard time saying no to Halloween Candy if it's around.

[00:00:58] I'm so happy that I'm [00:01:00] not working in the hospital anymore 'cause I used to work in the cancer center. It was so sweet. Like patients and their families, they would wanna bring food and snacks and treats in to, to feed the people who are caring for their family members or caring for themselves.

[00:01:16] And it is so kind. But boy, it can really be challenging to stay away from, those fresh bagels or fresh donuts or fresh, foods and bakery items and treats that they're making, or the giant bags of Halloween candy. I like for me, I love Halloween candy, so what do I do? How do I keep from eating it the whole month long?

[00:01:38] I, when I do buy it, it goes up into a cabinet. Usually I try to wait until the last minute to buy it and we have millions of kids that come through our neighborhood, like we have a hot neighborhood where they. Shipping kids in from other towns and stuff. 'cause we live on this area where it's a nice cul-de-sac so the cars aren't driving through quick by any means.

[00:01:59] [00:02:00] And so we have tons of kids coming through. So of course I, I need to buy enough candy, so I will buy two giant Costco bags worth of candy. But I try to wait until the last minute and then I put 'em up in the closet and we do not open that bag. 'cause you know what, once you open that bag, then oh, I'll just have one or I'll just have two.

[00:02:17] We do not open that bag into Halloween night. And then it's I, I have as much as I want. Because that's my, that's one night to splurge a little bit and then the next day I'm done. I try, but as the kids start to kinda wind down for the night, we're not getting as many trick or treaters.

[00:02:32] I'm looking at how much candy I have left and I'm starting to hand out handfuls. Just I wanna get rid of this. I don't want anymore sitting around the house. My husband's kind of the same way. I don't know about you. Like how do you deal with Halloween candy? Do you have any problem?

[00:02:44] Can you say no to it? Do you get the kind of candy to give out that you don't like? So you don't have to worry about that? I think everybody has their tricks. I think it's, regardless, that's, that can be challenging to say now to that, to the delicious chocolate and treats and stuff that you get at Halloween.

[00:02:59] But [00:03:00] anywho, so today, I. I was preparing for, what I wanted to do for this week's podcast, and I started thinking about questions that I most frequently get from new clients and past clients and current clients that I'm working with. And I have to say the one that kept coming up in my brain is by far about intermittent fasting.

[00:03:27] Women are like, ah, I just wanted to ask you what are your thoughts about intermittent fasting? Or Can you tell me a little bit more about it? Or, how can I do it? It. And I get it because everywhere you turn, someone is talking about intermittent fasting or somebody that you know has done it. You see it on social media, you hear your friends doing it.

[00:03:44] You read an article saying it's the secret to weight loss and energy. And when you're in midlife navigating those changing hormones and metabolism that doesn't feel like it used to, and maybe that little bit of frustration with how your body responds, it can [00:04:00] sound super tempting. You can be like, Hey, this is, this has gotta work for me.

[00:04:04] But here's the thing, intermittent fasting, it isn't the magic pill. It isn't automatically the right fit for every woman over 40. So in this episode, I wanna break it down for you. I wanna talk about kinda what it actually is, what the current research says for women over 40, the benefits, the risks, and who really should not be doing it.

[00:04:23] And then I wanna share a little bit about why it often becomes another. Short-term, quick fix, and how you can make, smaller, more sustainable changes that actually support your energy and metabolism long-term. Rather than jumping straight into intermittent fasting. Okay, so if you've been wondering, whether it's the missing piece for you, let's clear up that confusion.

[00:04:45] Let's talk about what really matters for women in midlife. So first of all, let's start with the basics, because before you can decide if it's right for you, you need to know exactly what intermittent fasting even means. It's not a specific [00:05:00] diet or a food plan, it's actually an eating schedule.

[00:05:03] You might also hear the term time restricted eating, which is actually a type of intermittent fasting where you eat all your meals within a set number of hours each day. While intermittent fasting is a broader term for any type of eating pattern that cycles between periods of eating and periods of fasting.

[00:05:23] And this can include things like whole day fasting or alternating eating and fasting days. The most common version of intermittent fasting is called 16 to eight. So basically it's 16 hours fasting to eight hours. It's is your eight hour eating window. And for example, you can stop eating maybe at 6:00 PM at night, and then you wouldn't eat again until 10:00 AM.

[00:05:48] Or maybe you stop eating at 4:00 PM and then you can start again at 8:00 AM the next morning. Another approach to intermittent fasting is called the five two approach, where you can eat [00:06:00] normally for five days a week and then you cut your calories down. Significantly two days a week. There's also, alternate day fasting where you eat every other day.

[00:06:12] So really at its core, intermittent fasting is about when you eat, not necessarily what you eat, okay? There's no specifications about what fe foods you should eat during those periods where you are eating. Now, here's what where it gets interesting and what the res current research says for women, 40 plus.

[00:06:30] It has. The research has greatly exploded over the last decade. Some of those studies do include women in midlife, and here's what they show. Intermittent fasting usually leads to a modest weight loss, about three to 8% of your body weight over three to 12 months. Okay? Huge range there, and that's about the same as what you'd see with good old fashioned calorie reduction.

[00:06:57] But some studies show with intermittent fasting, they'll [00:07:00] show improvements in things like fasting insulin or hemoglobin A1C. You can see cholesterol changes and blood pressure decreases, and when you combine fasting with strength training and like a good adequate protein intake that you hear me talk about all the time, just because, we, the intermittent fasting, you can see weight loss with it.

[00:07:23] And as always, we wanna make sure that if you are trying to lose weight, you're focused on focused fat loss while holding onto that lead muscle. And the way we do that is, is by, whatever we are doing, we're making sure we're getting in enough protein and we're making sure that we're doing strength training alongside it.

[00:07:41] Because the last thing we want is to lose muscle in our forties. 'cause we know that's already happening, just naturally, right? We wanna maintain that muscle let's talk about some potential benefits. So I already touched on a few things like fasting insulin and cholesterol and blood pressure and that stuff.

[00:07:57] I think the benefits with intermittent [00:08:00] fasting is that it can feel really simple and who doesn't want simple? Just eat within that certain window of time. Doesn't matter what eat or how much you eat, just eat and it can cut out late night Snacking, which for many women adds a lot of extra calories.

[00:08:18] Some people also find it helps with appetite regulation. Maybe, they're like not quite as hungry and it can definitely fit busy schedules. If you don't wanna think about breakfast or think about multiple meals during the day, maybe that means that when you go to work you only have to think about bringing your lunch and then you go home and have dinner in the evening and you're done.

[00:08:38] So there's definitely benefits. Certain research has shown also that if your brain is not thinking on, or I should say, your brain and your body are not focused on digestion, 'cause how often are we eating up to the point we're going to sleep. When your body's not having to focus on digestion and what to do with this food that's still sitting in your stomach or going through your GI tract, right?[00:09:00] 

[00:09:00] It can move into. It's called ketosis. So basically it means that the longer you fast, usually, I think they say it's after maybe a 12 hour or a 14 hour fast, you'll see that your body starts to use fat stores for energy, right? That's ketosis. Like the keto diet, right? But also giving your brain that time to not, to not have to worry about digestion.

[00:09:23] As you're sleeping, your brain can actually focus more on rest and recovery and just processing what you've gone through during that day. So it is, there's definitely a restorative piece to intermittent fasting that that can be very helpful in that sense for brain health. So now I wanna just touch on maybe some of the risks and the downsides.

[00:09:45] Because it wouldn't, it wouldn't be the full picture without looking at kind of the, that other side of the coin. One is with exercise, if you work out in the morning and you're fasting until noon, your energy, you're not gonna have as good of a performance. You're not gonna have as much energy [00:10:00] when you do that work in the morning, workout in the morning, especially if you're working out and then not eating for an additional two hours, which you can really be missing that window of.

[00:10:10] Replenishing those muscle glycogen stores that you just basically depleted when you were working out. And also giving your body those good amino acids to basically repair and heal those muscles and, after your workout. That's how we see our muscle strength. Is by that adaptation after your workout.

[00:10:30] Our muscles repair and recover, but they need those amino acids, right? So if we're not eating within a certain period of time after our workouts, that can really, take, it can make it more challenging also to hit those protein goals by the end of the day. If you're having to put, 50 grams of protein into each of your meals.

[00:10:46] If you're only doing two meals during the day, that can be challenging. It can actually, we can see that, that we have lean muscle loss instead of protecting that lean muscle, which we know we're losing after 40. So another risk, especially in women who [00:11:00] already feel a lot of food pressure, is that it can increase your preoccupation with eating.

[00:11:05] You end up thinking about food all day, waiting for that window to open up. And then when that win window is open, some women can overeat. And this, that cycle can be stressful, not freeing. And that's, we're trying to free women of these restrictions and the deprivation and the the laws and so much structure about what we're eating.

[00:11:27] We're trying to make a healthy relationship with food. And this isn't always the way to go, right? So for some women, it can actually decrease the healthiness of that relationship with food. Now I just wanna talk about who should not, definitely not try intermittent fasting because that's just as important.

[00:11:44] There's some situations where it isn't safe, or at least not without medical guidance. So if you've ever had an eating disorder or just that crappy relationship with food, I would not recommend it. It can be triggering. It's not recommended if you're pregnant or breastfeeding, [00:12:00] if you're taking insulin or blood pressure medications.

[00:12:04] Fasting can put you at risk of having, dangerous lows. And it's also not for women who are already underweight or unintentionally losing weight. And if you've got a high training load or thyroid or adrenal concerns, fasting can actually add more stress to your system. So it's not a one size fits all answer.

[00:12:23] And we wanna always be safe. 'cause that's the most important right. Okay, so now let's touch on why it can be that kind of quick fix mentality trap. It's a reality check because intermittent fasting often works because it decreases the amount of calories that you're eating in a day. It's not, it's not magical, you just might eat less calories within that whatever window that you're choosing.

[00:12:47] As compared to when you used to eat from the morning, you, the minute you woke up in the morning to the minute that you went to bed at night. It's not some magic about the fasting window. There is [00:13:00] the idea that, you hit that, that period where you do move into burning fat. I talked about ketosis when we get past that 12 or 14 hour window.

[00:13:10] That can promote that weight loss, but for the most part it's, people are eating less calories. We're in a calorie deficit, and that is causing some weight loss, right? So they see, the problem is that for a lot of women, it does feel restrictive and they see some weight loss in that first few weeks or months, and then they stop.

[00:13:27] And what happens? Yeah, they get frustrated and they go back to what they were doing before and they regain the weight. And the problem is when we lose, we always know when we lose that weight quickly with these quick fix approaches, we will lose muscle with that. And unfortunately then when we, we regain that weight quickly, we are gonna regain it as fat while, that combination is gonna slow our metabolism down, making it harder to keep the weight off and being in a worse spot at the end of it.

[00:13:56] So for many women, intermittent fasting just ends up being that other, that next, [00:14:00] short-term fix that doesn't last. So now I wanna propose a sustainable alternative, which is what I always, talk to women about, is that instead of jumping on to that quick fix, let's talk about what you can do instead.

[00:14:13] So one of my favorite simple step strategies is, you know what I call the after dinner close. So set a time, say. Seven 30 or eight o'clock, maybe even at six o'clock, depending on when you have dinner. So once you finish your evening meal, the kitchen's closed. No more snacks, no more grazing. Just, have something to drink.

[00:14:28] Have some water, have some tea. That one small habit can stop hundreds of extra calories from creeping in at night without making you feel deprived. And it can also put you into that, a little bit longer. Fasting state can also put you into that ketosis. And then next, just focus on building your meals around protein 25 to 35 grams at each meal.

[00:14:52] That usually adds up to about 90 to a hundred grams per day, which is what most men, women in midlife need to protect that muscle. So pair [00:15:00] that with those fiber rich carbs and healthy fats, and it's just gonna help you to feel much more full and satisfied. And you're not gonna be searching for those snacks after dinner.

[00:15:11] And of course, incorporating in that strength training. Making sure that we're protecting the muscle we have, making sure we're protecting our metabolisms, trying to get as many steps as we can. So walking on those non lifting days, staying hydrated and prioritizing sleep. So these are the things that kind of create that long lasting energy and our metabolism support.

[00:15:29] These are the things that are gonna promote fat loss, which ultimately is gonna help us to make us more sensitive to insulin, just like with the intermittent fasting. And it's not gonna have, there's no fad that's required. So at the end of the day, intermittent fasting isn't magic. If you love it and it works with your life, that's fantastic, but it feels stressful.

[00:15:48] If it feels restrictive, if it feels unsustainable, skip it. What matters most is building those habits that you can actually live with. So ones that protect your muscle, your metabolism, and your energy. In this [00:16:00] season of life, if you wanna dive deeper into this, I've created free guide called Intermittent Fasting After 40.

[00:16:06] You can read this first, it breaks down what we talked about today and gives you a seven day checklist of simple habits that you can try right now. You can grab in the show notes and just see if maybe, if it would be something for you. And as always, if this episode has helped you, please take a minute to leave a rate a rating, share it with a friend, or send me a message and let me know your thoughts.

[00:16:28] I would really appreciate it. And as always, just remember this is about progress over perfection. We're in this for the long haul and this is your season of strength. Have a fantastic day.