Which Heart Health Diet Should you Recommend for Your Patient?

Podcast Transcript

Announcer:

Welcome to Cleveland Clinic Cardiac Consult, brought to you by the Sydell and Arnold Miller Family Heart, Vascular, and Thoracic Institute at Cleveland Clinic.

Julia Zumpano, RD:

Hello, my name is Julia Zumpano. I'm a registered dietitian with Preventive Cardiology and Rehabilitation at the Cleveland Clinic.

Today I am going to discuss dietary controversies, including the ketogenic diet, the low-carb diet, plant-based diet, and intermittent fasting, and what is the evidence on the best diet for clinical practice and how to apply it. I will review the clinical implications of each plan, the pros and cons of each plan, and how to choose the best plan.

What is ketosis? Ketosis is a change in your metabolism from burning carbohydrates or glucose to burning fat for energy. Fat breakdown produces ketones, which can come from your diet in the form of dietary fat or your fat stores in your body. Ketones become your body and brain's main source of energy. Glucose levels decrease, insulin decreases, and your liver produces more ketones for energy for your brain.

The traditional ketogenic diet or keto, is a high-fat diet, which is very low in carbohydrates and provides moderate protein. Fats are your primary source of nutritional calories or energy. Another form of the ketogenic diet is called the protein-sparing modified fast. This diet is low in fat, it's still very low in carbohydrate, but high in protein. Fat and ketones are the primary source of energy, although protein is the primary source of calories.

The benefits and disadvantages. The traditional keto produces rapid weight loss. It also has been shown to help lower blood pressure, blood sugars, your waist circumference, triglycerides, and inflammation. Although it may increase LDL and it does not spare your muscle, so it can break down muscle in the rapid weight loss. The protein-sparing modified fast also produces rapid weight loss about three to five pounds per week, and there is potential for weight regain because of the strictness of the diet. Just like keto, it does also lower blood pressure, blood sugar, waist circumference, triglycerides, and inflammation. In addition, though, it can also lower total and LDL cholesterol.

How to get started? At Cleveland Clinic, we offer the protein-sparing modified fast as a ketogenic plan. It is a medically supervised program, which means that a physician or a nurse practitioner must supervise the patient on the program. They meet with the patient initially and generally every three months. The dietician's role is to provide the education of the diet, the diet supervision, and routine followup. The patient would meet with the dietician every four to six weeks.

As a part of the diet, there are labs that are required, which is a basic metabolic panel and a uric acid level. Because gout is quite common on this plan, we check uric acid every month. Daily supplements are also required in the form of potassium, which is prescribed by the provider that is supervising the plan, then over-the-counter supplements include magnesium, calcium, a multivitamin, additional sodium to your diet and supplemental fiber as needed.

There are contraindications to the ketogenic diet. We do not recommend keto if you're in end-stage renal disease, if you have diabetes Type 1, if you're in liver failure, if you're currently undergoing cancer treatment, if you've had a recent stroke or heart attack, if you suffer from cardiac arrhythmias, if you're pregnant or breastfeeding, if you have current gout or gallstones, and we do not recommend it for children or those who are normal or underweight.

Next plan that I will be discussing is the low carbohydrate diet. A low carbohydrate diet is classified as less than 26% of your total calories coming from carbohydrates or less than 130 grams of carbs per day. Moderate carb is anywhere from 26 to 44% of total calories from carbohydrates, and high carbohydrate would be 45% or greater.

What is a carb? Carbs are considered not only what we think of as grains and bread, but fruit are carbohydrates, and so is milk and yogurt are also considered carbohydrates. We have some items, grains such as oats, quinoa and barley, bread products, noodles, fruit as I mentioned, starchy vegetables like potatoes, peas, and corn, beans and lentils, of course all those snacky foods like crackers and chips and popcorn, sweets and desserts, and sweetened beverages, and of course milk and yogurt as well.

The good and the bad. So the benefits to a low-carb diet is it can reduce insulin, blood triglycerides, blood pressure, glucose, and body weight. The disadvantage though is that a low-carb diet can be hard to follow because in order to stay within your specific grams or percentage of calories, you do need to monitor your carb intake. Whether you use a food diary or an app, you need to measure your foods, you need to read labels, and in some cases you might actually need to carb count and calculate the amount of carbohydrates you're consuming for the day.

Next plan I'm going to discuss is the plant-based diet. At the Cleveland Clinic, we also encourage a whole foods plant-based diet, which is slightly different from just a plant-based diet. The whole foods plant-based diet really does focus on whole foods and very minimally processed foods. But a plant-based diet includes all foods that grow from the ground and excludes all foods that come from or that walk on the ground.

There are several clinical benefits of the plant-based diet. It can reduce your risk of developing Type 2 diabetes, obesity, heart disease, high cholesterol, and cancer. The mechanism that the plant-based diet does this is that the diet is very high in fiber, which regulates blood sugars in cholesterol. Fiber binds around something called bile in our guts, and that bile is composed of cholesterol and it can eliminate that bile with the body's waste. A plant-based diet is naturally low in saturated fat because it eliminates animal products, which are a primary source of saturated fat, which therefore can improve insulin sensitivity to the cells and reduce LDL. It promotes weight loss due to providing lower calorie foods, and it avoids group 1 and group 2A carcinogens: red meat and processed meats.

The disadvantage of a plant-based diet is that it can be very restrictive and strict, so we're eliminating a good part of a standard diet, American diet. It can be difficult to follow specifically in social settings, at family meals, eating out, or traveling. There's a potential to include too many carbohydrates, specifically because we're not eating meats and consuming only carbohydrate-based sources of protein that you can very easily get into too many carbs, and if you're not consuming enough protein on this plan, you could get into a trap of large portions of carbohydrate-based foods, such as pasta or rice or potatoes, to provide that fullness factor you could be searching for with the inadequate amount of protein or even fat.

There is potential for nutritional deficiencies. As I mentioned, you could be deficient in protein, calcium, B12, iron, zinc, Omega-3 fatty acid, and vitamin D. But note that these potential nutrition deficiencies are also present in a standard American diet, which is very heavily processed food-based.

Next, we'll talk about intermittent fasting. Intermittent fasting is defined as when you alternate between periods of eating and fasting. This type of eating is also described as patterns or cycles of fasting. There are several different forms of intermittent fasting. The five main ones include time-restricted eating, twice a week method, which is also called the five and two method, which is where you eat normally and healthy for five days, and you're eating a very low calorie diet for two days out of the week, which consists of about 500 calories. Alternate day fasting, which you're fasting every other day, and that's again, a very low calorie diet on every other day. And then the 24-hour fast is where you eat, stop, eat, so you take a full 24 hour. And then the one meal a day, very similar to the 24-hour method is where you're just consuming maybe just dinner and then the next day you just consume dinner.

I would like to focus on the time-restricted eating because it is the most commonly used in a clinical setting, and the reason it's because it's the easiest to follow, it's the least invasive, it's flexible, there's the least amount of negative side effects, and it can still provide all the same benefits, including decreasing your appetite, it can support weight loss, it can help boost brain function. It's been shown to improve concentration and alertness, and it can decrease inflammation.

We know, clinically, that time-restricted eating can improve your heart health by decreasing blood pressure, blood triglycerides, LDL, blood sugars, and insulin. It may also even boost brain function, which can improve nerve cell synthesis and protect against some neurodegenerative diseases.

The disadvantage. Weight loss can occur initially, although can taper off, and some people may develop symptoms when fasting for long periods of time, including dizziness or headache, irritability, weakness, fatigue, nausea, and hypoglycemia. These symptoms can be counteracted with adjustment of daily practices such as drinking enough water, or adjusting the fasting times, adjusting the fasting windows, and even supplementing with electrolytes.

The contraindications, we don't advise fasting if you're underweight or malnourished, if you are currently being treated for an eating or have a history of an eating disorder, if you're pregnant or nursing, and we do caution with menstruating women due to the potential to influence hormone fluctuations.

The benefits of intermittent fasting next to the benefits of a calorically restricted diet. The difference is there and in the middle, they both share the benefit of improving stress response, lowering blood pressure, improving insulin sensitivity, and lowering cholesterol.

Intermittent fasting does promote ketogenesis. It's linked with your circadian biology. The circadian rhythm is the natural cycle of your sleep and wake cycles. So we do encourage the time-restricted eating to be specific towards eating during the daylight hours and fasting during the nighttime hours. Weight loss is pronounced with those with elevated BMIs in intermittent fasting, and then there's promising long-term adherence, so it's pretty easy to stick to from a long-term perspective. On the other hand, caloric restriction obviously centers on the reduction of calories, does not include the ketogenesis or the circadian rhythm, but we do see weight loss amongst all BMIs.

Now, how do you find the right match? All these diets have been shown to have very many positive benefits, but really what's most important is that you ask questions, ask your patients questions. What do they think is a realistic goal for themselves, how motivated are they? Do they have family support or social support to follow a specific nutrition plan? What is their financial situation like? Do they do the grocery shopping? Do they prepare the meals, or is it someone else? Do we need to get someone else involved in their diet plan? And what are their dietary preferences? If we have a meat and potatoes kind of guy, I am not going to recommend a plant-based diet to him because it's going to be very unlikely that he's going to follow it.

The best diet is really the one that the patient will follow. There's so many influencing factors on what we eat, how we eat, and when we eat. There's diet history that plays a big role, their current dietary habits, their previous successes, what plans have worked for them in the past. I really try to look at what has worked and try to mimic or mirror that plan. Looking at their weight goal or their lowest adult weight. I commonly ask, "What was your weight when you graduated from high school? Where do you see yourself at a comfortable weight, a realistic and attainable weight?" I think a lot of times we get way too caught up in the number, and I try to reroute the patient to understanding the clinical benefits of even modest weight loss and just really focusing on what we can do to support healthy habits and modest weight loss. And then of course, looking at their medical history and their current health status. And then patient preference, as I mentioned, is really, really key.

So when it comes down to it, in summary, the best diet is really the one that you'll follow. I hope you learned something more about all the different diet plans we have to offer. If you're interested in any of these diet plans, I'd highly recommend you make an appointment to see one of the phenomenal registered dieticians at the Cleveland Clinic. Thank you.

Announcer:

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