Cheryl Martin (Host): We're hearing a lot about the keto diet these days, so let's learn more about this diet and the role of nutrition in cancer prevention with registered dietitian, Denice Hynd. She has a Master's Degree in Public Health. This is Mountain Medicine, a podcast from Northern Inyo Healthcare District.

I'm Cheryl Martin. Denice, welcome. So glad you're on to discuss the connection between diet and cancer prevention.

Denice Hynd: Thank you, Cheryl. I appreciate the time and opportunity to speak to our listeners.

Host: So, we hear a lot about the keto diet. What is it?

Denice Hynd: The keto diet is a diet that was created in the 1920s by different physicians because they were trying to find a diet therapy that would be beneficial to children actually suffering from seizure disorders like epilepsy. And they found that people suffering from epilepsy benefited from a very high-fat moderate protein diet. But with the advances in Pharmacy and Medicine, slowly that diet was no part of their prescription due to the creation of anti-seizure medications. However, they also saw weight loss during this time over a hundred years ago. And within the last 10, 15 years, this diet has resurfaced as another form of an Atkins diet or South Beach diet in that it promotes very low intake of carbohydrates and a very high intake of dietary fat.

Host: So specifically, what foods you've covered in general terms do the majority of Americans eat when following the keto diet, if you can just be more specific?

Denice Hynd: Typical foods that Americans eat following a keto diet would include things like butter. Some people would say that they choose grass-fed butter versus conventional butter. Conventional butter would be dairy cows, eating a diet that is rich in corn, which is not their natural diet. We know that alfalfa and greens, those are the natural diets of cows. Many people would be eating a lot of egg yolks, because the yolk is the primary source of fat in an egg versus the egg white is primarily protein. A lot of people might be consuming higher intakes of coconut oil. It might be consuming larger amounts of beef fat, so we always say four-legged animals like beef and pork have much higher concentrations of saturated fat versus our two-legged animals like chicken and turkey. They have less amounts of saturated fat. But this is what we call kind of like a whole foods keto diet where it's actually food in its intended form from nature. But unfortunately, due to processing and manufacturing and cheap foods, there's a lot of what we call packaged or there's a term that people use dirty keto, which would be things that are kind of like Slim Jims Jerkies that are really high in preservatives, high in sodium, a lot of packaged foods that a lot of scientists would say it's kind of like a food-like product, but not necessarily food. And so, the goal here for those who are wanting to have weight loss is to eat whatever they can that's high in fat and see the results, which would be weight loss. But in fact, it could be very harmful to your cardiovascular system.

Host: So, here's a big question, does the keto diet help reduce the risk for cancer?

Denice Hynd: If we look at the types of cancers that are in our communities, we see a rise in breast cancers, gastric cancers, and colorectal cancers. And these are the kind of cancers that really benefit from a high-fiber diet. We know with colorectal cancer across population studies communities who have a higher intake of packaged deli meats like bologna or highly preserved things like ham and pastrami, cooking on a high flame with four-legged animal products, those are the foods that can increase our risk for cancer. And so, those are also the foods that are part of the keto diet.

So, what we would prefer as dieticians is to really advise the community to increase their protein sources and their dietary choices from plant-based proteins, or even those animal proteins that come from two legged animals like turkey and chicken, or what we call no-legged animals. Fish don't have legs, and beans and lentils, they also don't have legs. And so, those contain the cancer-fighting properties like fiber, antioxidants, omega-3 fatty acids, as well as the obvious choice that a lot of people overlook is the foundation of our nutrition, which is fruits and vegetables in any form. Whether they're frozen, fresh, or canned in their own juice, those are all very beneficial. It could also be canned in light syrup. We would just encourage you to drain and rinse any canned fruits that are in syrup to reduce glycemic index.

Host: So you are more in line with the dietary choices that we've heard more about from other physicians and just across the board, more fish and chicken, less starches, more vegetables and fruits.

Denice Hynd: Exactly. Because sometimes when we prioritize weight loss, we're prioritizing weight loss and we fail to see or we don't want to see our risk for other conditions that may arise. And although we may see weight loss on these very extreme diets, we are forgetting that we still need to protect our brains from neurological declines. So, we want to have omega-3 fatty acids. We want to protect our GI and our colon. And so, we also need to have high fiber diets. A lot of people will say, "Well, sugar is bad." And nothing is good or bad, we don't want to add shame to food. We just really want to remind people that nobody became unhealthy eating pineapple. Nobody became unhealthy eating potatoes. Nobody became unhealthy having berries. It's the absence of these fruits and vegetables in our diet that are making us very unhealthy as a society.

Host: So, you're saying the absence of fruits and vegetables, so does that mean occasionally it's okay to have the potatoes or a dessert?

Denice Hynd: Of course. Oh my gosh, potatoes have a negative reputation. A lot of it is due to the low carb craze. And what people don't realize is that a plain, russet, humble Idaho potato has four times the potassium of a banana. And it just so happens that bananas are the gold standard for potassium because they travel well. They're ready to eat. You don't need to prepare them. And in reality, we know potassium is necessary as an electrolyte, but also to reduce cramping in our muscles as a person and as an athlete. But I always say we should throw baked potatoes at runners and at athletes because it would benefit them so much more than a banana.

Of course, you can't just eat a raw potato. So, potatoes are high in water, high in fiber, high in potassium, good sources of minerals because their skins are intact, and they come in direct contact with the soil, a lot of trace minerals in potatoes. All potatoes are beneficial. And the occasional dessert here and there absolutely is fine because we really want to also have a mindset of all things in variety and moderation, including moderation. And so, things are to be consumed intuitively, mindfully, and you don't ever want to feel shame for eating anything that you enjoy.

Host: Now, are there any other dietary choices that you would recommend for reducing the risk for cancer or reducing the risk of cancer reoccurring?

Denice Hynd: Yes. I've worked on one of the studies through the University of California, San Diego, and we were really looking at the recurrence of prostate cancer in men. And we looked at their lycopene intake and lycopene is a pigment. It's the red pigment that gives the red to tomatoes and to watermelons, similar to the beta-carotene or the carotenoids that we know give the orange pigment to carrots and pumpkin and things like that. And so, we always encourage men to increase their intake of lycopene-rich foods. And people would say, "Well, that's great because I love tomatoes." And although raw tomatoes are fine, we know that lycopene is more concentrated in its cooked form. So for example, a regular can of tomato sauce or tomato paste takes several pounds of fresh tomatoes to get it into sauce form. And so, one raw tomato is going to have an insignificant amount of lycopene versus a 14, 16 ounce can of tomato sauce that we would add to pizza or lasagna or chili or spaghetti. That's going to be great source of lycopene for men. And for women with breast cancer and men with breast cancer, we always encourage a lower glycemic, so lower, refined sugar, less sugar-sweetened beverages and higher complex carbohydrates. So, we're talking about brown rice, vegetables, the potatoes. We're talking about whole grains and oatmeal and quinoa, chia seeds and flax seeds, these kinds of things. Of course, omega-3 fatty acids.

At the end of the day, we want to eat foods that their pigments on the inside match their exterior skins. For example, a Granny Smith apple is green on the outside, but very pale in comparison on the inside. That's a good dietary choice. It's a great source of vitamin C and water and fiber, but it's a very low antioxidant food versus, let's say, a pomegranate or a cherry or a blueberry or a kale. Their exterior pigments match their interior pigments, so we know that those are rich in antioxidants just by the visualization alone. We don't need to know anything about nutrition when we go to the grocery store. We just want to look for those deeply rich pigmented food. There is an exception, of course, garlic, onions and cauliflower. They're very pale. They're very white in comparison, but they have a lot of antioxidants and a lot of vitamin C. But for the most part, your zucchinis, your cucumbers, and your apples, grapefruits and vegetables, but very low antioxidant due to their lack of pigmentation.

Host: Denice, any other eating behaviors or eating styles that are beneficial for optimal health? You've covered a lot already.

Denice Hynd: So, one of the things we always like to say as dietitians is there's an old Confucius saying, it's hara hachi bu, and this is a mantra that people living in Asia and also the longest lived people, we call them the Blue Zones or the Centennials, they practice this form of mindfulness where they only eat until they're about 75-80% capacity to allow the additional 20-25% of emptiness for digestion.

And essentially, we don't want to eat until we're full, we want to eat until we're no longer hungry. And it's a very easy boundary to cross if you are distracted while you're eating. If you're multitasking and driving and working while you're eating, it's very easy to be like, "Oh my gosh, I am so full," we've now crossed that boundary past that 75-80%. So, we want to ask ourselves, "Am I still hungry?" And if the answer is no, then that's a good idea to drop the fork, put your food down and take a moment of mindfulness to say, "I can come back to my plate In an hour, 45 minutes, or even the next day. I don't need to finish this large portion, because we're very desensitized to the portions in this country.

Host: And that would help us lose weight, wouldn't it? If we just simply, I love what you said, don't continue eating until you get full. At about 70%, stop. I love that.

Denice Hynd: Yes. And we know that this is one of the mantras and one of the pillars of health. When we look at longevity studies, the Blue Zones, the people that live naturally to well beyond their 100 years of age, they follow this kind of mindfulness. And here in the U.S., we can put that into practice because we are experts at multitasking while eating, and that's really not helping us with our behaviors around food, our relationship around food and our health outcomes.

Host: I'm wondering as well, Denice, if one of the issues is we have so many options in this country with so many snacks in the pantry. You go to the store and we're just overwhelmed with all these choices. So, the more stuff you have in your house, you're tempted to eat it.

Denice Hynd: One hundred percent. And there's actually some field studies out there that show our supermarkets of just even 50 years ago had about 10,000, 12,000 products in their stores. And now, with these mega stores, big box stores, we have almost 700,000, 750,000 options. And you'll see that when people come to the U.S. on vacation, especially people from Europe or in Australia, they'll come and they come and they're like, "Look at the American chip aisle," "Look at the American cereal aisle," "Look at their beverage aisles, just long and long aisles." And having it in the home is easy access. And so, what I always say as a dietitian is I want you to have that ice cream, but I want you to have the entire experience. So instead of having ice cream at home, how about you enjoy your dinner, do your chores after dinner. And then, as a family or as an individual, take your dog for a walk, go get frozen yogurt, go to Dairy Queen, go to Baskin Robbins, whatever's around the corner from you and enjoy the entire experience of ordering an ice cream, people watching you get fulfilled in more areas than one. And then, when you go home, you don't have that easy temptation anymore.

One of my favorite food writers, his name is Michael Pollan. He's a professor and he narrates a lot of these food documentaries. And he says have all the junk food you want as long as you make it from scratch. And when was the last time you made potato chips? Or when was the last time you churned your own ice cream, or you grew the wheat for your cake, and then you may churn the butter for your frosting. And he's right, it's our access to these foods that are a hindrance. And so back just 80 years ago, 100 years ago, we put in good labor hours to get that milk, to make that butter, to make that cream. We deserved that piece of pie. And now, with our cheap calories, two for $8 at the deli at your grocery store, you pick up several pies and they just sit on your counter. And that becomes a snack and that is not the way we should be thinking about pie as a snack.

Host: Well, I tell you, I think that if we all thought about that first and thought, "Now, what if I had to make this?" This would probably keep us from putting that potato chip in our mouth.

Denice Hynd: Yes. And a lot of clinicians and professionals that want to change the nutrition facts panels to also include how much physical activity you would need to participate in to burn that food. So for example, in other countries like Mexico, on the cereal boxes or juice or soda, right there on the front label, it says, "This food is very high in sugar." And it's a red, big label. And in the U.S. they're pushing for, the food labels to also say you would need to participate in 120 minutes of vigorous activity to burn the calories and the sugar from this 12 ounce can of soda. And that would be also very eye-opening as well.

Host: I agree. Well, Denice Hynd, thanks for sharing your insights on the keto diet, on nutrition, and cancer prevention. Extremely helpful. I'm putting it into practice. Thank you so much.

Denice Hynd: My pleasure.

Host: To learn more about health services at Northern Inyo Healthcare District, visit visit nih.org. And to hear more Mountain Medicine podcasts, visit NIH.org/mountainmedicine. Thanks for listening.