In this episode, Dr. Amy Von Sydow Green and Dr. Anastassia Amaro join Dr. Williams to discuss the evidence for what types of foods and diets are most healthy for our patients.
Kendal Williams, MD, MPH, is Director, Center for Evidence-based Practice, and Professor of Clinical Medicine. Dr. Williams is board certified in Internal Medicine. He currently
sees patients at Penn Internal Medicine Radnor
Refer a patient to Dr. Williams:
Transcript
Podcast transcript (PDF)
Kendal Williams, MD (Host): Welcome everyone to the Penn Primary Care Podcast. I'm your host, Dr. Kendal Williams. So welcome back to another year of podcast. We're a little delayed in getting our year started this year, but we're starting off with a bang, with a huge and important topic, something that affects every human on the planet and is often discussed in our primary care setting, and that is what should human beings eat?
So there's a tremendous amount of confusion on this topic over the years. People are always being marketed different types of diets, various forms of supplements, and they come into our offices and ask us about it. And so we're supposed to be experts on all this and also help people guide through this.
So I wanted to bring this question to the fore. This isn't about weight loss. This is about what are the dietary patterns of eating that lead to a longer life, [00:01:00] that lead to a reduction in some of the cardiovascular outcomes, reduction in the risk of cancer and so forth. So that's what we're going to talk about today.
This particular podcast is directed to patients as much as providers. I'm hoping in my ever efficient way of doing things to ask my patients to listen to this podcast and rather than me repeating everything. So I'm hoping that we can have that discussion today and use it in our offices for patients to educate themselves.
So, to do that, I invited on one of Penn's great experts, Dr. Amy Von Sydow Green, works in the Obesity and Metabolic Center at Penn. Dr. Von Sydow Green is an M.D. from Sweden. And came to this country and did a master's in nutrition and is a Registered Dietitian. She not only works with the Obesity Metabolic Center, she also runs nutrition programs and group nutrition classes. She's a cookbook writer. So she's really the person to ask [00:02:00] about this basic question of what should humans eat. Amy, thanks for coming.
Amy Von Sydow Green, MD: Thank you so much. I'm so happy to be here. I'm excited about this discussion and, yeah, I just look forward to talking about nutrition, which is my passion.
Host: So Amy, I know you do this every day, all day and probably on weekends, but let's start with, I think, what is in some ways a ball of confusion. I mean, if you go on the internet, and start looking around, you will get recommended all kinds of dietary patterns; low fat, low carb, different other diets that are named different things, and marketed supplements and so forth.
And it seems to me, and I want you to comment on this, it seems to me that in the last decade or so, we've moved away from some of this focus on nutrients themselves, you know, proteins, the carbohydrates and so forth into more an understanding of whole foods and dietary patterns. But you can [00:03:00] correct me on that.
Amy Von Sydow Green, MD: Yes. So I would absolutely agree with that. So there has been an evolution in nutrition recommendations. So, even if we look back to the 90s, the dietary guidelines for Americans, the first sentence was eat a diet low in fat, saturated fat, and cholesterol. Then we moved on to recommending fruit and vegetables.
There really has been an evolution. So now we are more the American Heart Association, the Dietary Guidelines for Americans. They're all focusing on an overall dietary pattern because as humans we don't eat percentages of macronutrients. macronutrients I think telling someone to eat 30 percent fat in their diet, it's unlikely to change much because it's not going to mean much for us, and most of us are not going to be measuring x grams of this or that.
So it makes more sense to recommend a dietary pattern, and within that pattern, make sure that our patients, [00:04:00] ourselves, that we can follow this pattern, with our personal preferences, our cultural preferences, childhood memories. There's so much that comes into food. So really focusing on sort of an overall healthy diet pattern, makes a lot of sense.
Host: So let's talk about those dietary patterns and what has been shown to be most effective scientifically. And when we say most effective, what we mean is, because we've studied these now in trials of various forms, to see if certain dietary patterns lower cardiovascular outcomes, lower the risk of heart attack and stroke specifically, if people have a lower risk of cancer, and if they live longer, right?
So when we're talking about these dietary patterns, we want to ask the question, does it really work? And when we ask that question, does it really work? We mean, does it reduce the things that people die of, right? And so, in my mind, I think the two ones that I know most about or at least, understand best are Mediterranean diet and [00:05:00] the DASH diet that seem to have the largest degree of scientific evidence behind them.
Amy Von Sydow Green, MD: Yes, so the Mediterranean diet and the DASH diet are two great dietary patterns and I really do want to bring up also the dietary guidelines for Americans. So the USDA and the HHS, they have been publishing these evidence based guidelines since 1980, every five years. They are based in science. There's going to be a lot of overlap if we look at the Dietary Guidelines for Americans, the DASH diet, and the Mediterranean diet. But I do think, let's not forget about the basics, the Dietary Guidelines for Americans that do recommend a healthy pattern at all life stages. A lot of similarities between these three. It really, I would say, in a way is, a different way of recommending patterns. So, slightly different focus, so if we look at the DASH diet, for example, dietary approaches to stop [00:06:00] hypertension, was formulated specifically to reduce hypertension, and it will give you recommendations that are similar to the Mediterranean diet. But there will be a bit more of a focus on portion sizes. There's more of a focus on limiting sodium. So sodium typically is not mentioned in the Mediterranean diet. So, I agree, there's so much overwhelming information out there on the internet for us as health professionals, for our patients.
I have so many patients who come in to me and say, there's just nothing that I can eat anymore. There's something wrong with everything, and I don't know what to choose. So I think we have a lot to win by going back to the basics. So if we're looking at what Americans eat today, so about 1 in 10 adult Americans will meet the recommended intake of fruit or vegetables.
So that's pretty low. So we got a lot to offer if we [00:07:00] focus on just saying, increase fruit and vegetables, increase whole grains, reduce sweets and saturated fats. We can make life much less complicated for our patients and really focus on a few very simple guidelines. Most of our patients probably know about this, so we may also need to focus more on helping them figure out ways to make small shifts in their diets to move towards a healthier dietary pattern.
Host: So if I come in to see you and I say, forget, you know, what I eat now. I want to shift my eating pattern to something that's the most healthy for me. And I'm sure this comes to you often. What do you say? How do you describe the way people should eat? And which you said, you know, DASH, Mediterranean, they're all very similar. And so they boil down to some common themes. And what are those themes?
Amy Von Sydow Green, MD: They really do. They really do. So, I would always look at what [00:08:00] you're eating now, but if we're just starting and someone may ask me, what are you going to be thinking about when you're talking to me about my diet? So I will look at regular meals. That'll be my first step, talking about the mealtime routine throughout the day.
Then I will look at vegetable intake. I will look at fruit intake. I will ask about types of carbohydrates. So for bread, pasta, I will ask, is it a whole grain? So fruit, vegetables, whole grains. I will discuss protein because protein does help make a meal more satisfying, give you a longer lasting satiety. And then I will ask about the things that we may need to limit.
So sweets, saturated fats. And when it comes to fats, I will also discuss healthy fats, and we may get into a discussion about what the different types of fats are in our [00:09:00] diet.
Host: So when I do this, and I want you to correct me if I'm wrong, I start by saying, the first step is to sort of minimize things that are not good. So, processed carbohydrates, in any form, that are made from white sugar, you should minimize to the best of your ability.
You should minimize over processed, even vegetables, chips and so forth, right? And then, you should really focus on eating things that come out of the ground, ideally as close to when they were picked out of the ground as possible, So, that's fruits, that's vegetables, that's seeds, and nuts, and beans, and lentils. And then that should be the sort of the foundation.
And then, with olive oil. So, you talked about saturated, unsaturated fats and so forth. I always tell people you should eat olive oil for everything. And I think there are good studies that show that, olive oil, when used for cooking as well as for salads and other things is beneficial [00:10:00] and it is a real food that has demonstrable effect on health.
So I tell them you should start with that and everything else should sort of be layered on top. Is that a fair way to do it?
Amy Von Sydow Green, MD: I would say that is a fair way of doing it. I will say I typically go the other way around. So when I talk to someone. I will often start with saying, what can we add to your diet, right now? So can we add some fruits? Can we add some vegetables? Can we add some whole grains? Can we add some healthy fats in the form of nuts, seeds, olive oil, avocado, fatty fish?
So when we start adding these things in, so when we start, figuring out a healthy and delicious breakfast that you can easily make. If we have ideas for quick dinners, quick lunches, you may find that you're not needing the highly processed foods quite as [00:11:00] much, and without even thinking about it, you're cutting down on them.
So that is often the way that I would go about things. So start with what can we add in right now? What's one thing you can add in tomorrow to shift your eating habits towards a healthier pattern?
Host: I grew up in a rural farmhouse in Pennsylvania with a diet heavily influenced by British food, I'd say. I don't mean to knock British food, it was very meat and potatoes heavy. We did have a garden. My grandmother was a Depression era person, and so knew to do a victory garden.
And so we had a garden and all of that, but we had a lot of baked goods. We had a lot of processed stuff. So you know, when I went off to college, I'd actually never had rice in my life. And I didn't know anything about Indian food or Persian food or even Italian food was pizza from the local place, you know.
So, it took years, I think, of shifting and experimenting with different foods [00:12:00] to eat what I eat now, which is largely what I recommended, and it's completely different. And I almost eat almost nothing of what I grew up eating. I don't eat any meat. I hardly ever eat potatoes, although potatoes are very good and so forth.
But so I think, you know, everybody has to go through that process on some level, right?
Amy Von Sydow Green, MD: Absolutely. Yes. And I think this is a really good story to bring up, that we all come into our diet with a lot of background. We grew up eating a certain way, that is part of what can make it really hard to make changes, and you may have to challenge yourself, trying new flavors, trying new foods, and that can be hard.
And so, I often try to make that a little bit more simple and also to encourage a gradual approach. So it may not be about making a complete change in your diet. Add frozen vegetables to your dinner. It takes two minutes. Pop some broccoli in the microwave. If you want to get fancy, a squeeze of lemon and some Parmesan [00:13:00] cheese on top, then that's a good side dish that you're done with in a few minutes.
And so I think most of our patients and ourselves, we don't have unlimited time to get food on the table. And that's something that makes it hard for people. We don't have unlimited time. We don't have unlimited resources. And so that's something to really take into consideration when we're figuring out the healthy dietary pattern for ourselves or our patients.
How much time do we want to put in doing that. Many of my patients, love my idea of just bringing a salad kit for lunch at work. So get a pre made salad kit, add some protein, boiled eggs, a tuna pouch, grilled chicken strips, and you're done. And that took about two or three minutes to prepare.
So those are things that I often try to bring up. It doesn't have to be so complicated and so hard to eat a healthier diet.
Host: So [00:14:00] let's step back a little bit and just go into the evidence for these dietary patterns. And we've talked about DASH, which was developed by Harvard scientists, as I recall, for hypertension, the diet to stop hypertension, that's what it stands for. And then, the Mediterranean diet, as I understand it, came out of just the observation that people who lived in those regions, the so called blue zones, right, and related to that, but folks who followed similar patterns, at least to the peoples around the Mediterranean, which are heavy in seeds and nuts, heavy in vegetables that grew out of the ground, olive oil being used almost exclusively.
I, said these things before, but I think it bears repeating to say exactly what we mean when we say the Mediterranean diet. They weren't necessarily low carb, right, Amy? I mean, you're talking about folks that are eating rice, they're eating pasta daily, as part of their diets.
Amy Von Sydow Green, MD: Absolutely. Yes. So, when we talk about the Mediterranean diet, lots of fruit, vegetables, whole [00:15:00] grains. So yes, so not a low carb diet, a focus on healthy fats. Also not a low fat diet. And something that's interesting to know is also that in the Mediterranean diet, there are moderate amounts of meats and eggs and dairy.
So a little bit lower in meat, eggs, dairy. And what I think is interesting also to know, so there's a lot of research on the Mediterranean diet, and when we're looking at some of the most significant studies, so the Lyon study back in the 90s, a really interesting part of that, and when I was sort of going back and reviewing some of that science, is that they actually used canola oil margarine, as their intervention.
So the group with the Mediterranean diet, that diet was enriched with this healthy fat, canola oil, which actually, so I'm Swedish, so I have to mention that that's a type of fat, the rapeseed oil, canola oil, that is more common in the Nordic and Baltic countries, so sort of Northern Europe. However, a [00:16:00] big part of the Mediterranean diet, does seem to be about this replacing saturated fats.
So the saturated fats are fats that we're getting in animal products. So, dairy, meat, so replacing that type of fat with unsaturated fat that we get in fatty fish, olive oil. Also this canola oil, and nuts and seeds. So a big part of the evidence behind the Mediterranean diet is really based in this sort of, we're replacing the saturated fat with unsaturated fat.
And that seems to have a big difference for cardiovascular health. So that's really an interesting piece of information for us to use. Yeah.
Host: So for those who aren't familiar with the technology of saturated fats versus unsaturated fats, I guess you could roughly say that unsaturated fats come from vegetable seeds and nuts. Saturated fats come from animal products, cheese, meat, butter, so forth.
Amy Von Sydow Green, MD: Yeah. And you can say in a really easy way for someone [00:17:00] to know if it's a saturated or unsaturated fat is, so saturated fats are solid in room temperature. So butter, is a typical saturated fat, but the unsaturated fats are oils in room temperature. So olive oil, canola oil, of course the avocado, it doesn't quite add up there, but, it's about the chemical structure of the fat.
Host: I want to get to this topic of eating meat versus pescatarian versus vegetarian versus vegan. But before we get to that, I think it's important to note that the diets that were talked about that have good evidence for benefit were not vegetarian necessarily, although they were heavily favored vegetables as a primary food source. Right? Is that a way to describe it?
Amy Von Sydow Green, MD: That is a perfect way to describe it. So I like to describe to my patients that I see meat more as a side. So the vegetable you can see as the main. So we often, when we plan a meal, we often think, well, we're going to have chicken. [00:18:00] But I would really like us to instead say we're going to have amazing roasted vegetables and we may have some chicken to go with it.
Something like that.
Host: Years ago, I got married and my wife was a vegetarian and I had vegetarian leanings I guess you could say, and had phased the meat more and more out of my diet. But when I thought of what to eat, and we weren't married yet, and she was living in California, and I was sort of trying to make this shift on my own, I found myself basically just, instead of meat, potatoes, and a green, I was just eating the potatoes and the green, and, just leaving off the meat.
But actually, what really helped me was to start to learn some ethnic cuisine, to learn to cook dal, Indian, lentil, dish, which is delicious, and, you know, some Persian food as well, that could be made vegetarian that was heavy and really just wonderful stews that you put over rice.
And, that really helped me shift my diet away [00:19:00] from meat, into these healthier options and become a vegetarian where I actually had stuff that I could eat because for a while there I was like, I don't think I have anything to eat, 'cause I was so used to starting my plate out with a meat and then adding the vegetables in as opposed to what you're describing where you shift the difference.
Amy Von Sydow Green, MD: Absolutely. If you're moving away from meats, and into a more vegetarian or even vegan diet, it will take a little bit of exploration and thinking to make sure that you're getting that protein in, that you're feeling full and satisfied, that you are actually making a healthy change.
And, what you're describing there, legumes, beans, lentils, there's definitely some good evidence that those are great protein sources, may have some benefit preventing Type 2 diabetes, tons of fiber, good for our digestion. So, that would be another small shift, even, saying, well, once a week, I'm going to [00:20:00] replace meat with chickpeas, kidney beans, lentils, one of those.
Host: And what we call the Mediterranean diet. I mean, the core of it can really be shifted into a Japanese diet or an Asian, more East Asian diet with stir fries you know, Indian culture has this long history of vegetarian heavy vegetable eating. So there's a lot of what we say is Mediterranean. We think about the regions around the Mediterranean, obviously, from North Africa and Israel and Lebanon and so forth. But really that dietary pattern is reflected in a lot of areas of the world where they're eating healthy foods. And you can simply take those same components and make a stir fry out of them, right?
Yeah
Amy Von Sydow Green, MD: Yes. And I would say, I think the Mediterranean diet is an amazing dietary pattern, but I very rarely find myself using that word because I think it's a word that can easily confuse someone. So you may think of, well, what actually for me myself, I know what it is, but still if someone says Mediterranean diet, I [00:21:00] think of an Italian vacation with an Aperol spritz and a pizza.
So that's just me. And I know that's not what it's about, but I would say yes, the guidelines of the Mediterranean diet can be put into place with any type of cultural food. I think that makes, maybe sometimes the Mediterranean diet, the word may not be the most helpful because it actually may confuse someone. And so that brings me back to thinking about the dietary guidelines for Americans, where we really focus more on just those food groups that all Americans would do well with eating more of and without bringing in any cultural component, for the patient right there.
Host: If you read the medical literature, they say you should advise people the Mediterranean diet, but I understand what you're saying. I mean, I'm often looking for somebody who's not from a Mediterranean culture, has no idea, doesn't particularly like hummus.
And you know, you're sort of there saying, well, that's not quite what I mean. And I see exactly what you mean with the terminology. But the [00:22:00] basics are the same, even if you're going off of the guidelines from the U S. And, in my reading on this, and you can correct me on that, in terms of things like cardiovascular outcomes, lower risk of cancer, and so forth, we're talking about probably about a 20 to 30 percent reduction in those outcomes.
In my experience in reading this literature is if you can't remember what it is exactly, it's roughly 20 to 30 percent. Is that about right?
Amy Von Sydow Green, MD: Yes, that's just about right. There are, of course, some varying numbers, but, yeah, larger trials are showing around that 30%, yes.
Host: So, I want to get into this meat eating versus pescetarian versus vegetarian versus vegan. I listened to a very interesting lecture recently of a gentleman sort of reporting on the findings of the Oxford studies that have been done comparing these dietary patterns, particularly meat eaters, vegetarians versus vegans.
And they looked at biomarkers, so that, they had various laboratory studies. And of course, being [00:23:00] Britain, they had all the national health records, so they were able to tie it to outcomes. And it, was very interesting, and, for the most part, the vegetarians were the ones that did the best.
Again, sort of a 20-30 percent reduction cardiovascular outcomes. Depending on the cancer, it seemed to be a bit of a mix. Bowel and GI cancers more clearly reduced with vegetarian diets than with meat eating diets. And then, of course, veganism was another piece that we can get to, but what is your understanding of this literature?
Amy Von Sydow Green, MD: I would say that it's difficult because when we're looking at literature on red meat, there are different definitions on what is considered a high meat intake, what is considered a low meat intake. And so we can see that there are consistent health risks, it seems, with eating more than about five, six ounces of red meat per day.
Whereas we can't see much health risk when we're looking at [00:24:00] under three, three and a half ounces per day. We can see health benefits when we're replacing red meat with poultry, fish, vegetarian types of protein sources. So I think where we are right now is we may not be able to say that someone necessarily needs to be a vegan or vegetarian for health benefits, but we can say definitely that it's a good thing to reduce red meats to a moderate level. And so a small serving, a few times a week. And when we come to the processed meats, such as pepperoni, different types of ham, hot dogs; those do seem to increase health risks, even at relatively small intakes.
Host: And so you said five ounces. How much is five ounces of meat?
Amy Von Sydow Green, MD: So five ounces of meat, if we're looking at say three, four ounces is typically a deck of cards, type of size. So it's not a huge portion. So I would [00:25:00] say probably a regular portion for most people of meat a couple of times a week, that would be a good guideline to go with.
Host: I'm just trying to put this as concrete as a hamburger from McDonald's or whatever, or a Big Mac, that's going to be more than five ounces of meat. That's probably sounds like what you're describing might be as much as eight ounces of meat.
Amy Von Sydow Green, MD: Something along those lines, yes, so I would say, eating red meat two, three times a week, most likely is going to be okay, and that will also be what you can fit if you follow the guidelines from the USDA, from the American Heart Association of eating fish two to three times a week, and also maybe trying to have a vegetarian meal once a week, then that's sort of where you end up.
Host: From my reading, it did not seem that being a vegan as opposed to vegetarian had proven benefits. The BMI of folks that are vegan tend to be lower, I guess for obvious reasons, [00:26:00] but, there's also the issue of B12 supplementation that needs to be taken to, because folks do have a deficiency sometimes in B12, B vitamins, because of the absence of exposure to animal bacteria, more than anything.
But how do you advise people who are thinking about those dietary patterns, meaning vegetarian versus vegan.
Amy Von Sydow Green, MD: I would say it depends a little bit on how much time and care the person would like to put into figuring out their diet. So with the vegetarian diet, you have a few really easy protein sources that you can use. So, you could use, for example, low fat or non fat Greek yogurt is a great protein source. Low fat cheeses, cottage cheese, eggs. That makes it much, much easier to manage a vegetarian diet, I would say, when it comes to getting your protein intake, when we compare it to a vegan diet. And a vegan diet can be a great diet, but it's going to take a little bit more [00:27:00] care to make sure that you're getting all your nutrition in.
Host: Let's talk about protein, because this comes up a lot. And I have patients who supplement their protein intentionally because they've been told to do so by somebody usually on the internet. How much protein should a human have a day?
Amy Von Sydow Green, MD: The lowest recommended daily intake is about 0.8 grams per kilo of body weight. For most people, it ends up so that you want about 20 grams of protein with each of your meals. Generally, a lack of protein is not something that we see commonly in someone's diet. However, as we get older, we need a little bit more protein to maintain our muscle mass.
If you're, for some reason, eating less, if you have a lower appetite, you may also not be getting enough protein. And also for someone who's struggling, feeling full after meals, feeling hungry soon after a meal, or is working on managing their blood sugar, [00:28:00] they may really benefit from making sure to add protein with each of their meals.
Host: Because it leads to a sense of fulfillment in your meal. I want to ask about this more because getting that amount of protein, so for a 70 kilogram human, that would be like roughly 56 grams of protein a day, which can be a fair amount. I mean, you know, if you start to look at what's in tofu or what are in nuts and seeds and so forth. I mean, even if you are a meat eater, you have to eat a fair amount to get that level.
So I've often wondered where those targets come from. And whether they're really accurate, I suppose. Because the point you made is that we don't have people walking around who are generally deficient in protein. That's usually not a problem.
Amy Von Sydow Green, MD: That's true, that's usually not a problem. I can't say that I know exactly how the 0.8 grams per kilo, how that was developed, but it is an established sort of lowest amount needed for bodily functions. [00:29:00] And I think the 56, 60 to 80 grams a day, it's easier than we think because we're getting protein from so many different sources.
And so, if I'm working with someone who is a vegetarian or is working on a more plant based diet, there's such a good saying in Sweden, many small drops of water or something like that. So what you'll need to do is you'll need to work with many sources of protein in each meal. So for example, say if you're having salad with chickpeas for dinner, the chickpeas are going to give you some protein. Maybe you're getting 8 to 10 grams from the chickpeas. You may sprinkle some seeds on, that'll give you another couple of grams. You may even make a dressing with some Greek yogurt. That'll give you a couple of grams. Maybe you chop up some nuts as well. Even your vegetables are gonna give you a few grams of protein.
So when we're talking about protein, sometimes we think specifically about those protein sources like meat, fish, eggs, yogurt, [00:30:00] dairy. But there are many other foods that also contain protein. Of course, the legumes, for example, that's, those are a great source of protein, fiber.
I wouldn't be surprised if many dietary guidelines in the next few years are going to include legumes as sort of its own food group, because it's a really great food to include in your diet in terms of fiber, protein, vitamins. So we may have to puzzle it together a little bit, but we can definitely reach that good amount of protein intake.
Host: How about protein supplements that some people take if they're doing heavy workouts and want to gain more muscle? Do they make a difference?
Amy Von Sydow Green, MD: So protein supplements can be a very convenient and easy way to add extra protein. And so for someone who, for example, is a bodybuilder, which of course is not most of us, they may for optimal muscle synthesis, they may want up to even two grams per kilo of protein. And [00:31:00] so that can be really hard to do without getting a very high amount of calories, when you're using regular food. So for them, a protein supplement, a protein powder can be just a great sort of tool to get that extra protein in. And, and I also see some of my patients who are having a hard time getting protein in, they may enjoy a protein shake, something like that. And it can be helpful as part of a healthy dietary pattern.
Host: Well, we're starting to transition into a different question, and that is like the value of individual components. And I want to go back on this a little bit. So we talked about meats. Red meats are different than white meats, you know chicken and fish, I'm going to summarize and maybe you can comment but you said red meat in small amounts, two to three times a week, less than five ounces, you know, seems to be safe.
But some of the more processed meats can be dangerous even in small amounts; hot dogs, pepperoni, sausage, and so forth. Those [00:32:00] Slim Jims you get from the convenience store when you're doing long drives, I don't know anything about that. But, we know that diets that are rich in fish seem to be better even for you. So there's, there's actually a positive recommendation for eating fish.
Amy Von Sydow Green, MD: Absolutely yes. So fish, rich in protein, low in saturated fat. Some fatty fish has a lot of good healthy fats. It has vitamin D, minerals. So twice a week is a recommendation from the American Heart Association. Fewer than one in five Americans actually has fish twice a week. And I find that there are some people who shy away from fish because it's a little bit tricky to cook.
I can understand that. Getting a sort of whole fish, that's not so easy to manage. We also of course have canned tuna, that's a good option, or canned salmon. But yes, lots of benefits to eating fish twice a week. And then we may [00:33:00] have some people who have a good question. And that is, what about the mercury in the fish?
What about pesticides in fish? And that's a good question. So yes, especially some fish types are high in mercury, swordfish, shark. I'm not want to eat shark. I don't think we eat that very often, some types of tuna. But that twice a week.
That definitely for anyone would strike a good balance where you would not get high amounts of mercury or or other pesticides than you from the fish.
Host: My understanding is you can get some of those similar fatty acids in walnuts and some other sources that are not fish if you wanted to get omega 3 fatty acids, for instance, right?
Amy Von Sydow Green, MD: Yes, yes, definitely.
Host: I'm going to run some other ones past. I remember seeing a study years ago, that looked at just nuts, and folks that eat nuts, a handful or two handfuls of nuts a day versus those that don't, showed health benefits, just from eating nuts. Now, this is probably separated from a dietary [00:34:00] pattern. People who eat nuts tend to be folks that are more attentive and probably eating a Mediterranean based diet, which we now know is beneficial, but nevertheless. Any comment about nuts specifically?
Amy Von Sydow Green, MD: So I think nuts are a great, easy, easy way to improve your diet. So yes, having a handful of nuts every day, having some almonds and a banana or an apple as an afternoon snack. Great way to improve your diet. You're gonna get healthy fats, fiber. A couple of grams of protein, so yes to the nuts and the research 100 percent agrees with us there as well.
Host: When we talk about vegetables, obviously there's a wide spectrum of the types of vegetables. I remember years ago reading a very helpful book called Living on the Wild Side, which you may know, but it was about the different types of vegetables, their history and their health benefits, but it was very high on crucifers in particular. So broccoli, cauliflower, kale, at the high end of the vegetable pyramid, if you will, in terms of health benefits. [00:35:00] But, also tomatoes, potatoes, asparagus, all these other things. But is there any thoughts on the types of vegetables we should be bringing into our diets?
Amy Von Sydow Green, MD: I don't want to talk down any types of vegetables, so I think in my book all vegetables are amazing. It is a good thing to try to eat a variety of vegetables. They have slightly different nutrients in them. Some vegetables have a higher fiber content. Different colored vegetables are going to have different antioxidants.
So, I like the idea of trying to eat the rainbow, exploring, trying new foods. I think eating different colors of vegetables would be a good guideline. And yes, some of those vegetables you mentioned, they are going to have a higher fiber content compared to, say, cucumber or iceberg lettuce, something like that.
Host: Let's talk about preparation. We recently got an air fryer. That's actually quite a remarkable thing. Actually, you can spray olive oil on it and you get French fries that taste just like they [00:36:00] come from Five Guys, right? They're delicious. But they're remarkably more healthy than deep frying something in oil.
So, I know in our household, we've learned a lot about the preparation of vegetables in ways that I learned a lot from Philadelphia restaurants, you know, just getting, different vegetables and how they were dressing them up and how to make it better. But, do you have any recommendations in that regard?
Amy Von Sydow Green, MD: I also love the airfryer. It's a very fun tool to use. I was just making potato wedges in mine yesterday. And I will say if you haven't made it yet, cannellini beans in the airfryer, crunchy cannellini beans, really, really nice. It could be sort of a snack. Instead of croutons on our salad. So I love the air fryer.
I love roasted vegetables. I just bought a new cookbook by the two chefs that run Zahav restaurant. So they made a cookbook called Zahav at Home. And it has so many great vegetable, vegetable recipes. I made a salad with shredded carrots and cabbage and lots of herbs and some raisins in it. And it's the type of salad that [00:37:00] lasts for four or five days. So that's a cookbook I would recommend.
Host: There's a pattern in restaurants now where you go Sweet Greens is one of these places, Chipotle to some degree. You go and they give you a salad, but there's more in it. There's, guacamole and there's rice and there's beans. And I suppose that can be more referred to more generally as bowls as opposed to salads.
So it's like an augmented salad with some protein and some carbs that might make you feel more full. A friend of ours recommended that as a great way to sort of make a dinner quickly. Just throw something together and you have a variety of options there. I just threw that out there. It was a nice recommendation. It's been helpful.
Amy Von Sydow Green, MD: Yes, and I think also just that idea to sort of be inspired by what you see at, say, Chipotle. I know a lot of my patients love Chipotle. I love it myself. I have one around the corner.
So really making something like that at home, cooking some brown rice, mixing with black [00:38:00] beans, buying some store bought salsa, some avocado, and maybe grilled chicken strips.
You're pretty much there putting that bowl together and maybe a handful of lettuce or baby spinach. So I really like the idea of making bowls. I do a lot of bowls at home. It's also a good meal for a family because I think sometimes, it's hard when you have kids, different ages, everyone wants different things.
So if you serve a sort of bowl style meal, everyone can make their own. So you can just have, different toppings, but the base can be sort of the rice and beans and the chicken, and then, one child might add the cucumber, one child adds the corn, everyone can put together their own meal, because that's something also that prevents us sometimes from eating healthy, that, maybe you're cooking for family members and they're really whiny.
Host: That's right. I know something about that. Actually a fair amount about that. Okay. I have three more questions for you before we end this, coffee. It seems that every study I ever see about coffee, comes out in the positive for coffee, that we should be drinking [00:39:00] it up, you know, to a certain level. I think it's like four cups a day is the upper limit of what's healthy. But how do you advise your patients?
Amy Von Sydow Green, MD: I am with you there. It does seem like there's a lot of positive studies when it comes to coffee and health. And, when we're looking at cardiovascular disease, blood lipids. So two to four cups does seem to reduce the risk of cardiovascular disease. And that could possibly be because of some nutrients in the coffee.
Coffee actually has some minerals, it has some polyphenols that are sort of plant nutrients, that people may not get enough of from fruit and vegetables. So there's a logic to coffee being good for us. Unfiltered coffee has some lipid components that can increase cholesterol levels. So that may be something to think about. For the person who specifically is working on lowering cholesterol, if they're drinking, say, a Turkish style coffee an unfiltered coffee, that may be something to think about. And that's when we're really getting into the [00:40:00] details with someone who's maybe working very specifically. And then I would say it's important to know that caffeine, we metabolize it differently. There's genetic differences in, how quickly that caffeine, moves away from your system. So you may be a person who can drink a cup of coffee at 5 p.m. and fall asleep, or you may be someone who needs to have their last cup of coffee at 10 a.m. or otherwise you'll struggle. And so I think coffee is a little complex and sometimes I'm suspicious. I think probably a lot of researchers drink a lot of coffee and so they really don't want to see anything negative coming out about their coffee.
Host: It's like alcohol all those years that they had positive studies. All right. I'm confused about salt and, the DASH diet, of course, is a low salt. I just have no idea if I'm eating too much. I don't know. How do you advise folks about what's a healthy salt intake?
Amy Von Sydow Green, MD: So with salt, we come back to that there is a specific number that's usually [00:41:00] recommended. So it's under 2,300 or 2,500 milligrams per day. The average American eats around 3,500 milligrams a day. And I would say if we're eating more fruit and vegetables, more of all those whole foods, we are going to eat less sodium. So that comes naturally that way. And if we're looking at, for example, let's just say a classic cheesesteak, from Wawa, 2000 to 3000 milligrams of sodium in just that one sandwich. So eating out, definitely you're most likely getting more sodium than you do well with.
And we do know that increased sodium intake will result in higher risk of cardiovascular disease and higher blood pressure. So, if we're looking at that DASH diet, they have sort of two stages, and so the more intense version of the DASH diet, you want to lower your sodium intake to under 1,500 milligrams, and that's really hard to do because so many of the foods that we eat have [00:42:00] sodium in them.
Cheese, I mean, any type of packaged food, when we're eating out, foods tend to be really salty, soy sauce, so many foods have sodium in them. So it's tricky, but it is still worthwhile, especially for a patient who is trying to reduce their blood pressure, making lifestyle changes. It's a good idea to try to work on lowering sodium intake.
Host: And if you're cooking at home, and you're seasoning yourself, and you season your rice or something with a couple of pinches. I don't have a good sense of how much is okay. Do you have any specific advice that you say?
Amy Von Sydow Green, MD: So I would say, go as low as you can go because we still want the food to taste good. And this is something I will say, I really struggle with myself as someone who actually has high blood pressure and would like to reduce my sodium intake. I love a pinch of salt on the tomato or a little extra salt in my salad dressing. And so it's hard. Mrs. Dash, it's a good thing, but
Host: It doesn't [00:43:00] taste the same.
Amy Von Sydow Green, MD: Oh. Not quite the same.
Host: I know, neither do the potassium chloride supplements. They're good, but they're not as different, they're different. It takes a while to get used to it. But I did get used to Stevia over time, so I guess I could try and get used to the potassium chloride, which brings up the last question I want to ask you, and that is about sweeteners, because I think there's a fair amount of controversy.
When folks ask me about this, I make the point that, listen, highly processed sugar is not normal either, because a lot of people will say, I don't want to eat something that's so foreign to my body, but highly processed sugar is not normal either.
And we know it's highly harmful to people. But when you look at the low calorie sweeteners that are out there, there's sucralose and there's the red and pink packets that I don't use myself very often. I can't remember the name of, and then there's Stevia, you know, which is plant based, and then there's a couple of others, erythritol, which I think we have some growing concerns about. Can you help us navigate through that landscape?
Amy Von Sydow Green, MD: So there's a whole group of these sweeteners [00:44:00] that are called artificial sweeteners or non nutritive sweeteners. So, so it's aspartame, sucralose. The ones that we have here are approved as safe by the FDA, and really there's no human outcome data, that shows any negative health effects in the doses that they are consumed in.
So these sweeteners are typically between 200 up to 600 times more sweet than our sugar. And so we need so little of them. When we see things like that, sweetener has been shown to be very dangerous. It tends to be in animal studies in very, very large doses. And those doses we would not come up to unless we consumed, say, 30, 40 cans of Diet Coke a day and, not even, and that would have to be every single day.
So we're very far away from getting there. There has been some concern about artificial sweeteners having an effect on insulin, on blood sugars. [00:45:00] That hasn't been consistently shown either. So I would say what we can say right now is that, the evidence tells us that we can say it's safe to use these artificial sweeteners.
And for example, you can see in studies, there's one study on a group of people who had lost weight and maintained a lower weight for a while. They tend to actually have a pretty high consumption of artificial sweeteners. So of course I would say to my patients and for myself, water is the preferred drink, water with lemon, iced tea, but if you want that sweet, I would absolutely prefer you have a diet soda rather than a high sugar fruit juice or high sugar, some sort of drink. And, and a lot of drinks that we get out are so high in sugar. So I was just looking at the, something called the Energizer or something at Wawa and it had 49 grams of carbohydrate, which can be compared with two doughnuts or something like that.
So I would say let's not [00:46:00] be too scared of the artificial sweeteners. Most likely, having one or two diet drinks a day is not going to do any harm. It's probably not where we want to focus our energy in making changes. It comes far behind the important things that we've talked about earlier on. Fruits, vegetables, whole grains, legumes, healthy fats, all that stuff.
Host: Amy, this has been a great discussion. I really want to thank you very much. I mean, everything you said is supported by studies. We didn't go over all of those individual studies, but I know you know them. You sent lot of them to me before the podcast. So, this is really, I think, where the science is at right now in terms of understanding of the healthiest ways for humans to eat, right?
Amy Von Sydow Green, MD: I would say so. And, hopefully everyone listening has gotten some good ideas, some good advice. And I also want to say, really, there's no need to focus on perfection in your diet. I think we all need to focus on making the changes that we can make, in a reasonable way, [00:47:00] the changes that we can maintain. And, that may mean different things for different people.
Host: I just want to hover on that point because almost nothing that we eat is harmful in small amounts on an occasional basis, right? We talked about meats and ice cream and sugars. None of those are harmful on an occasional basis, right?
Amy Von Sydow Green, MD: That's absolutely right. And I think I would go as far as saying, they are healthy because some of those foods, when we eat them in small amounts, we typically eat them in situations where we may be together with people celebrating something, celebrating a birthday. And so I think, those ways of eating those foods can be giving us health benefits because it may mean that we're really enjoying community, being with our families, being with our friends.
Host: Amy, thank you so much for coming on. And, we may have you back again if more questions come in about this. And, this is really a wide ranging discussion and somewhat informal, but really, much appreciated. Thank you.
Amy Von Sydow Green, MD: Thank you.
Host: So we're going to be [00:48:00] tackling this a little bit from a different angle in another episode coming up where we talk about lifestyle medicine, but we're there, we're going to be sort of pulling it all together in sort of not just eating but also sleep and exercise and so forth. But for now, thank you everyone, for joining the Penn Primary Care Podcast. Please join us again next time.
Disclaimer: Please note that this podcast is for educational purposes only. For specific questions, please contact your physician, and if an emergency, please call 9-1-1 or go to the nearest emergency department.