[00:00:00] Adam Walker: From Susan G Komen, this is Real Pink, A podcast exploring real stories, struggles, and triumphs related to breast cancer. We’re taking the conversation from the doctor’s office to your living room.
[00:00:17] Joining me today is Dr. Jennifer Ligibel, a Susan G Komen scholar and Komen grantee, professor of medicine at Harvard Medical School, senior physician at the Dana-Farber Cancer Institute, and an expert in the impact of lifestyle factors, cancer risk and outcomes. Through more than a dozen lifestyle intervention trials, Dr.
[00:00:37] Ligibel has evaluated the impact of exercise, weight loss, fitness, body composition and quality of life in cancer patients and survivors. And I’ll admit, I love sweet treats and there are times throughout the year that I eat more than my fair share. Not recently. And I’m sure that I’m not alone, that this overindulgence, uh, about this overindulgence.
[00:01:00] So I’m excited for you to tell us what we need to know about. The foods that we eat and the lifestyle decisions that we make and how that affects our risk of cancer, in particular breast cancer. So let’s get into it. Dr. Ligibel, welcome back to the show.
[00:01:14] Dr. Jennifer Ligibel: Thank you so much.
[00:01:16] Adam Walker: Alright, so, uh, let’s start with, uh, our genes.
[00:01:20] Okay, that seems like a good place to start. Uh, we can’t change our genes, but what factors are within our control as it relates to outcomes and, and the risk of breast cancer.
[00:01:29] Dr. Jennifer Ligibel: Absolutely. And so there are a number of things about breast cancer risk that we can’t really change. So breast cancer is more common in women.
[00:01:39] Breast cancer is more common as people get older. Um, those are things that are, you know, generally beyond our, our control. Um. Breast cancer, as you say, is more common in people with certain hereditary genes, but breast cancer also is related to lifestyle factors, and so there’s a lot of evidence that shows that women, uh
[00:02:04] who are more physically active are at lower risk of developing breast cancer. And that’s true for both younger women and older women. Uh, that is true for different kinds of breast cancer. So hormonally driven cancers and non hormonally driven cancers. I say women, um, we do know that men also get breast cancer much less commonly, but we don’t know as much about the links between lifestyle factors and cancer risk in men, partially because it’s harder to study when it’s a smaller group.
[00:02:34] So I will say women a lot. It doesn’t mean that it isn’t applicable to men. We just don’t have as much evidence.
[00:02:41] Adam Walker: That’s fair. Yeah.
[00:02:42] Dr. Jennifer Ligibel: The other lifestyle factor that has really consistently been linked to breast cancer risk is body weight, and in particular obesity. Okay. Uh, we know that obesity is a very strong risk factor for the development of breast cancer in women after menopause.
[00:03:00] Hmm. And studies have shown that kind of each five kilogram per meter squared increase in body mass index. And I know this is a lot of, but that’s kind of when we, when we think about, um, these categorizations of weight, as somebody who is in kind of the normal weight range or the overweight range or the obese range, there’s usually about this five kilogram per meter squared
[00:03:26] difference. Um, and the, that like body mass index kind of takes, it basically normalizes your weight for your height. So 30 pounds for somebody who’s six feet tall has a different relationship to extra body weight, extra kind of fat tissue, which is really kind of what we’re trying to get at here than it does for somebody who’s five feet tall.
[00:03:47] And so that’s what this whole concept of body mass index is basically your weight normalized for your height. So this kind of increment is it where, what would take somebody from being overweight to being obese or kind of different levels of obesity. And so that kind of increment in weight is associated
[00:04:08] generally with about a 10% increase in the risk of breast cancer. So if you have two women and one of them has a body mass index in the normal range and one in the obese range, there’s about a 20% difference in their risk of developing breast cancer over the course of their lifetime.
[00:04:24] Adam Walker: So that sounds significant to me, like that’s, that seems very significant.
[00:04:29] Is that, am I overstating it?
[00:04:31] Dr. Jennifer Ligibel: No. Well, and it’s, so it is a 20% kind of relative increase. Okay. So it doesn’t mean like that there’s, I know this is all, we’re getting into statistics now. It got into this whole, this whole piece of normalizing height for weight, but Yeah, yeah. Right, right, right. You know, there’s.
[00:04:49] Yeah. So, um, so it’s, it’s, it’s, it’s kind of a, um, ba you take whatever your risk was and you kind of amplify it by 20%. The other thing that’s, that’s interesting is the relationship between weight and breast cancer risk in younger women. Um, there have been data over the years that have suggested that, for reasons that we don’t completely understand, having excess body weight when you’re younger seems to actually have a, be a linked to a lower risk of developing breast cancer.
[00:05:22] Recently there’s been some data that have suggested that that might not be so simple. Um, okay. That in fact, um, that there may be a relationship specifically in kind of European populations of Caucasian women with heavier body weight and lower breast cancer risk for hormonally driven cancers. But in fact, there seems to be a higher risk of some of the more aggressive tumors, the hormonally insensitive tumors with excess body weight in younger women, and
[00:05:56] we’re learning more about this. Um, but it is probably not a good breast cancer prevention strategy to try to have a lot of extra body weight in your premenopausal years. Probably not good for health more generally. Yeah. Um, yeah.
[00:06:09] Adam Walker: Feels like that cause a, a whole load of other problems as well. So Yeah, I, I, I get that.
[00:06:15] But, but it is interesting to me, like, like that, that seems to be a major, uh, risk factor for, for women, you know, that are of kind of breast cancer age, uh, which is really interesting. Um, has your, has your research revealed anything about whether like increasing or decreasing breast cancer risk when these factors are modified?
[00:06:33] Like how they can be affected?
[00:06:35] Dr. Jennifer Ligibel: That is a great question. Um, and something that there’s not enough research looking at, you know, how we actually lower somebody’s risk of developing breast cancer through lifestyle modification. But there’s some really interesting evidence that has come from the bariatric surgery, um, literature.
[00:06:55] So, um, these usually aren’t randomized trials. It’s really hard to randomize people to get a surgical procedure versus not. But what they’ve done is that these groups that do large numbers of bariatric surgery procedures create these kind of registries where they match the people who have bariatric surgery.
[00:07:15] To other individuals that have kind of the same body mass index, we’re getting back to that body mass index, um, the same age, the same kind of number of medical conditions. And then they follow the two groups over time. And what they’ve seen actually is that the people that have bariatric surgery, have about a 40% lower risk of developing cancer of any type compared to people who don’t have the procedure.
[00:07:40] And then looking at breast cancer specifically, there is about a 40 to 50% lower risk of men of, uh, breast cancer after menopause in people who have bariatric surgery, which is incredible when you think about it. It’s half the risk. Um. So, you know, I think that there’s a lot of interest in the GLP-1 receptor agonist, the weight loss drugs, whether they will have a similar
[00:08:06] link to lower breast cancer risks. So far that hasn’t really been shown, although they have shown that people who are using weight loss drugs seem to be at lower risk of developing other kinds of cancer compared to people who don’t. Colon cancer, um, risks seems to be lower, um, as well as some other cancers, but not breast cancer so far.
[00:08:25] So I think more we need to learn there.
[00:08:28] Adam Walker: Interesting. All right, so we’ve talked about, you know, lowering risk to prevent diagnosis. Uh, what should breast cancer survivors know? Like how can they make choices to reduce risk of recurrence?
[00:08:40] Dr. Jennifer Ligibel: Absolutely. That’s such an important question because I think a lot of people,
[00:08:44] when they’re diagnosed with breast cancer, the first thing they’re thinking about is, what can I do to help improve my long-term odds? And we do know from, again, studies that kind of look at patterns and connections that are not randomized trials, we know that, um, having a higher body weight when you’re diagnosed with breast cancer and not exercising when you’re diagnosed with breast cancer are both linked to a higher risk of having the cancer return and unfortunately of dying from breast cancer.
[00:09:15] Mm-hmm. We also know from that same kind of evidence, kind of asking people what they do, following them over time. That people who exercise regularly after they’re diagnosed seem to have a lower risk of their cancer coming back. So even if you’re not exercising a lot when you’re diagnosed, if you start to do that, there does seem to be a favorable effect.
[00:09:36] Now, we don’t know if it’s really from the exercise because people make all kinds of lifestyle changes when they’re diagnosed. Mm-hmm. And so, right. Hard to know. But people who have kind of a healthier fitness pattern are less likely to have their cancer come back. In terms of weight loss, it’s a huge question and it’s one that we’re trying to answer with a large randomized trial that we’ve been conducting now over almost the last decade.
[00:10:02] Uh, very much supported by Susan G Komen, as well as National Cancer Institute, breast Cancer Research Foundation, a very big trial. That is looking at whether losing weight through a diet and exercise based weight loss program will reduce the risk of cancer recurrence for women who have overweight or obesity when they’re diagnosed with breast cancer.
[00:10:25] Hmm. So we enrolled 3,200 women. Um, they’ve all now finished the lifestyle program. Um, we actually, uh, the, the Komen Foundation has recently funded a really interesting. Study looking at kinda long-term changes in diet and exercise behaviors, and we’re still collecting that information, uh, to be able to look at how this
[00:10:47] weight loss program affects people’s cancer recurrence risk, and then being able to look at, one of the things with breast cancer that’s so hard is that some people have these recurrences years after their diagnosis, what we call late recurrence. And so we’re really excited now to be able to not just kind of look
[00:11:07] overall at whether people’s cancer comes back after they’ve been in this weight loss program, but whether there specifically is an impact on some of these recurrences that happen 10, 20 years later.
[00:11:20] Adam Walker: Mm.
[00:11:20] Dr. Jennifer Ligibel: So we don’t have the answer to that yet, but hopefully in the next few years we’ll know a lot more.
[00:11:25] Adam Walker: It’s coming. The answer’s coming. Okay. And that’s, that’s why the studies are happening, right? Uh, so, all right. So I’m curious, like starting a new exercise regimen or program, starting a new diet, it’s like very overwhelming, right? Like no, like it’s so hard to know where to start. So do you have any tangible advice on where someone should start if they’re just getting into an exercise program, maybe they’re overwhelmed or where or where to start by adjusting their diet?
[00:11:49] Dr. Jennifer Ligibel: Um. So, you know, you kind of raise a question about whether it’s best to try to change your lifestyle more broadly at the same time, or to make change. Fair point. Yeah. Sequentially. Yeah. There’s been some research that’s looked at that that’s been kind of inconclusive and I think it kind of depends on the person.
[00:12:08] Sometimes if you are exercising more, you feel a little bit compelled to change your diet and eat better and vice versa. Sometimes if you are eating better, you kind of have more energy and you wanna do things, you know, you wanna take a more holistic look at your lifestyle, but then other people feel like you know one thing at a time.
[00:12:28] It’s a lot to focus on. So in our large scale weight loss trial, we actually started with dietary change and then added exercise later. Um. I think conversely, if somebody is just starting treatment, if they’re getting chemotherapy in particular, the evidence is stronger for making exercise changes during chemotherapy to help prevent losing all your muscle mass and becoming really deconditioned.
[00:12:54] So if I’m talking to a patient who’s just starting some chemotherapy or radiation, I would say to them, start with exercise. Hmm. Kind of look at what you’re doing now and try to add exercise gradually. Try to incorporate some strength training exercise, which doesn’t mean necessarily like weightlifting, but even doing like abdominal work core exercises to kind of maintain muscle.
[00:13:17] So, um, people starting treatment, I would start with exercise. For someone who wants to start with a weight loss program, I think one of the most important things is to kind of recognize the portion sizes that you’re eating because that is so out of whack in this country. Mm-hmm. Yeah. Um, you can consume really healthy food, but if you eat too much of it, you still won’t lose weight.
[00:13:40] And so, kind of thinking about portion sizes, um, thinking about it’s often helpful to start with meeting with a dietician in some way, shape, or form to kind of take a look at your dietary plan and what you’re eating. Um, but I, if people wanna do something simple, I usually tell them to just start by looking at, you know, what’s the portion size of the food that you’re eating?
[00:14:01] And then, you know, you, you can look at the ingredients label and then see what you’re eating, how many servings you’re eating of that food.
[00:14:09] Adam Walker: Yeah. Yeah.It’s interesting you mention portions. because I was thinking more like, oh yeah, may, maybe you have like ice cream, but a small portion. But you were talking about having like two larger portions of, of healthy foods can also be like be a problem, which is inter like I’ve never thought of it that way. Well,
[00:14:26] Dr. Jennifer Ligibel: I would say that healthy-ish foods maybe.
[00:14:28] I would say that larger portions of unhealthy foods are probably a bigger problem.
[00:14:32] Adam Walker: Much bigger. Much bigger. Yeah.
[00:14:34] Dr. Jennifer Ligibel: Yeah. I do have people who come to me and say like everything I eat is healthy, but yet I can’t lose weight. And so I think it’s just important. Oh, right. Recognize dietary quality is important and I, I should have started this with the caveat that I am not a dietician and that
[00:14:49] Adam Walker: Of course.
[00:14:49] Yeah,
[00:14:50] of course.
[00:14:50] Dr. Jennifer Ligibel: Yeah. Always recommend. I’m sure of my nutrition colleagues are rolling their eyes and saying, yeah, just. Dr. Ligibel, just send your patients to us
[00:14:58] to start,
[00:14:58] send them over. We’ll take care of them. Yeah.
[00:15:01] Adam Walker: But yeah. Alright, so, alright, so, so then on the, uh, let’s say the less healthy food side of things, like, let’s say, you know, somebody loves a bowl of ice cream, or in my case, uh, Reese’s Cups or a glass of wine, but they, they do wanna be mindful and, and try to eat healthy and try to avoid cancer.
[00:15:18] I mean, do you have any, any advice for like, how to moderate that?
[00:15:22] Dr. Jennifer Ligibel: I think, you know, with all things, I am a huge believer in moderation. Mm-hmm. Um, if you create a dietary plan where there are many things that are just taboo or forbidden, people have a really hard time sticking to those types of diets longer term.
[00:15:39] And so, you know, I think that thinking about, you know, if your special treat is ice cream, then you know, a small portion occasionally is not something that is going, you know, and then you, you kind of shape your eating that day around knowing that you’re going to have that. And so, you know, perhaps you don’t have some other calories earlier in the day.
[00:16:01] You don’t do it every day. But I think the other piece that’s important is to not adopt this all or nothing kind of mindset that, okay, I had a little bit of ice cream, forget it. This day is ruined. Now I’m going to have the french fries to go along with it and I’m gonna have, you know.
[00:16:16] Adam Walker: Yeah, don’t double down.
[00:16:18] Right.
[00:16:18] Dr. Jennifer Ligibel: Exactly.
[00:16:19] Yeah.
[00:16:19] You know, kind of of recovering from, you know. Not, people are not perfect. You’re going to slip from the plan that you’ve made. The important thing, honestly, is how you recover from that.
[00:16:31] Adam Walker: That’s right. Yeah. It’s interesting to me too, like thinking about foods and there there’s a pretty big difference between sim sometimes like similar foods, like for example, um, I like peanut butter and I’ve got like a little app that I use to scan and tell me how healthy foods are labels that I, that I’m at the grocery store and I scanned one that I used to buy.
[00:16:48] It got a very bad score and I scanned another one and it got a pretty good score. They’re very similar peanut butters, and so I think maybe just like taking that next level up of like the next healthy option can also be helpful as you’re, you know, trying to eat more healthy as well. So buy the better version.
[00:17:05] Dr. Jennifer Ligibel: Yeah, I mean, I, I think one of the things that’s so confusing to people is like, what is healthy? And that’s a great, I think that trying to get to, you know foods that kind of are as much as they were when they came out of the ground. Probably, you know, we do the, all the alter processing and things changes
[00:17:30] foods sometimes makes people eat more than they would’ve normally, like they, you know, when you add a lot of additives and preservatives and things like that, sometimes it makes the food so palatable. All of your normal body signals that tell you to stop eating because you’re full sort of go out the window.
[00:17:46] Um, and so, you know, but it is, I think it can be confusing for people. Um, you know, for a while we used to think that healthy meant low fat and Right. Yeah. And that really, you know, that’s when all the additives and everything and that turned into high sugar, which
[00:18:02] Adam Walker: is even worse. Yeah, that’s right. Yeah. I mean, but you’re, you make a great point.
[00:18:07] Like, like what? The definition of healthy does change over time, I think as we learn and, and grow more.
[00:18:15] Dr. Jennifer Ligibel: Yeah. You know, but I think if you get to the, the recommendation that people eat primarily plant-based foods, try to stay away from things that are processed. Yes. Right. Whole grains. Lots of fruits and vegetables.
[00:18:30] That hasn’t really changed. No, no, you’re right. You’re right. I think what changes that’s is we kind of go through these, we’re going to like, take a shortcut or create a, you know, I mean is that, that’s kind of what everybody wants in some ways is like, you know, this is the, the shortcut to keeping your weight in good range.
[00:18:47] And, you know, and I, I think that if we kind of stick to the fruits and vegetables. Whole grains, lean proteins.
[00:18:56] Adam Walker: That’s right. Yep. Avoid the fads Changed. Yeah, avoid the fads.
[00:18:59] Dr. Jennifer Ligibel: Avoid, avoid, avoid unhealthy fat.
[00:19:01] Adam Walker: Yeah, that’s right. Yeah, I totally agree. No, no, I fads like FADS, the, oh, fads. There’s all these, yeah, there’s all, because there’s all these, like, you know, these mo like this is the healthy thing and like, just to your point, just stick to the basics, you know, the, the, the stuff that we know is, is good food.
[00:19:15] All right, so all, so, uh, a different topic here. Let’s talk guilt after receiving a diagnosis for a minute. Um, I know I’ve heard a lot on the show guests talk about how they think back to their pre-diagnosis lifestyle and they wonder if they might have somehow, you know, done something, eaten something, whatever that caused their cancer.
[00:19:34] What would you say to women and men that struggle with that?
[00:19:38] Dr. Jennifer Ligibel: I, I think that’s really common. I mean, everybody wants a reason and part of that is because they wanna make sure that whatever that reason was, that they fix it. And so that, you know, that kind of gives some power to prevent cancer from happening again.
[00:19:54] Um, and you certainly, we wanna harness the energy, um, in a positive way of making healthy lifestyle changes after diagnosis. But I think the reality is for most individuals, unless they do have kind of a change in a gene that directly leads to cancer forming, we don’t know why they developed breast cancer.
[00:20:14] It’s so multifactorial. There’s a hormonal piece to it. There are probably epigenetic changes. I, you know, I usually try to have people harness that energy to think forward rather than think backward.
[00:20:29] Adam Walker: I mean, I, I think to your point, like there’s so many factors that you, we can never know. Like there’s no way to ever track all the factors that go into something like that.
[00:20:36] And, and so hard, like obsessing over it doesn’t help, right? No, but, but thinking for the future, like, like focusing on what’s next, that, that can be helpful. So, um, all right. So where can our listeners find support or resources to learn more about managing their breast cancer risk?
[00:20:53] Dr. Jennifer Ligibel: Absolutely. So, um, the Susan G Komen website, definitely a very good place to find evidence-based information
[00:21:01] because I think this is an area where it can be tricky. You can really find all kinds of things out there. American Cancer Society, also really nice materials, patient facing. The NCI has a, uh, booklet called Facing Forward that is kind of for cancer survivors focused on diet and exercise after diagnosis.
[00:21:21] Um, so I think that, you know, there are a lot of good resources out there.
[00:21:25] Adam Walker: That’s right. There’s great, lots of great resources out there, uh, hopefully including this podcast episode. So, uh, well, Dr. Ligibel, it’s so nice to see you again. I, I really appreciate the work that you’re doing. Thank you for talking to us about, you know, all these risk factors and nutrition and, uh, thanks for joining us on the show today.
[00:21:40] Dr. Jennifer Ligibel: Absolutely happy to be here.
[00:21:45] Adam Walker: Thanks for listening to Real Pink, a weekly podcast by Susan G Komen. For more episodes, visit real pink.komen.org. And for more on breast cancer, visit komen.org. Make sure to check out at Susan G Komen on social media. I’m your host, Adam. You can find me on Twitter at AJ Walker or on my blog adam j walker.com.