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Diet Myths and the Real Truth with Dr Adrienne Youdim

05/08/19 Adrienne Youdim, MD, David Geffen School of Medicine at UCLA|Cedars Sinai Medical Center|Dehl Nutrition;

Season 1 | Episode 3

Description: Trying to lose weight can be extremely frustrating. With so many new diet myths and trends hitting the market, it’s hard for anyone to determine which are right for them. Some of these fad diets and weight-loss myths are not only unhealthy ways to quickly lose weight, but could actually cause long-term problems for your health. Dr. Adrienne Youdim is our guest today to break down today’s most popular diet myths and share tips for healthy, sustainable weight loss.






>> Newscasters: The Keto-diet. Many people including myself call it the holy grail when it comes to health. It is the latest diet fad- eating like the cavemen. The paleo diet is popular with …today we are talking about the Whole30 diet. So what exactly is Gluten and why is it so problematic.

We will be back with the meat lovers diet.


>> Narrator: Welcome to the medical myths podcast. Where we set the record straight on today’s most talked about medical topics and questions. On every episode, we’ll hear stories from the front lines of medical care to help dispel common myths and answer the questions you’ve been itching to ask your doctor. And remember you can always find more information on this week’s topic and hundreds of others on Now here’s your host editor-in-chief of the Merck Manuals, Dr. Robert Porter.

>> Dr. Robert Porter: Welcome to the medical myths podcast. I’m your host Dr. Robert Porter, Editor in chief of the Merck Manuals. On this episode, we welcome Dr. Adrienne Youdim. Dr. Youdim is an associate professor of medicine at the UCLA Geffen School of Medicine and Cedars-Sinai Medical Center. She’s a specialist in clinical nutrition and obesity and has a practice in nutrition and weight management in Beverly Hills, and she has over ten years of experience in this field. Dr. Youdim is also one of our Merck Manuals authors who’ve been very helpful to us over the years.

>> Dr. Adrienne Youdim: Hi Dr. Porter, thanks for having me it’s a pleasure to be with you.

>> Dr. Porter: Now there are a lot of diets out there, and some of them are extreme enough that they’re actually unhealthy and can cause some harm to people. So Dr. Youdim is here with us to break down some of today’s most popular diets and discuss what’s healthy. So Dr. Youdim, my clinical practice was all in the emergency room, so the only dietary problems I saw were a result of the seafood diet. Where a patient sees food they eat it. But I don’t see patients who were on unusual diets because they just wouldn’t come into the E.R., But you must have seen people who’ve gotten fairly sick following a diet, can you tell me about of those?

>> Dr. Youdim: Yeah most of these diets can be well tolerated even though they’re extreme but, in some cases, they can result in really serious and significant side effects. We did have one patient who was following the Keto diet for several weeks and came in with what we call pretty severe Keto flu. It is a consolation of symptoms that includes really significant fatigue, a certain degree of dehydration and in this case our patient also had some electrolyte abnormalities from following this diet. So again it can result in some serious side effects.

>> Dr. Porter:  So, it can really throw your body chemistry off. Well speaking of the Keto diet, what is that all about? What’s Ketosis?  That’s the goal of the diet, right?

>> Dr. Youdim: Exactly, so the Keto diet is the latest rendition of the low carb craze. It’s essentially a diet in which people consume high amounts of protein and fat in order to induce what we call Ketosis. So what happens in the body is that when carbohydrates are limited the sugar source gets depleted and is therefore no longer available to the brain as a source of energy. So the body begins to convert fat into what we call Ketone bodies which are readily accessible to the brain as an energy source and that’s essentially what ketosis is.

>> Dr. Porter: So, how do you enter into a state of Ketosis?

>> Dr. Youdim: Now in order to get into Ketosis people have to severely restrict their carbohydrate intake, and we tend to consider carbohydrates only as: bread, rice, pasta, but we forget that fruits and vegetables are also carbohydrates as well. In order for people to enter into ketosis, not do they have to restrict the so-called bad carbs but they have to restrict good carbs like fruits, vegetables even beans and legumes.

>> Dr. Porter: Wow that seems pretty restrictive; does it really help people lose weight?

>> Dr. Youdim: Right, it is pretty restrictive. So the Keto diet is primarily protein and fat, and while you are eliminating a whole food source, you’re eliminating carbohydrates. And, again about 80% of the American diet consists of carbohydrates so as you can imagine people are going to lose weight when they eliminate such a broad food group or food category.

>> Dr. Porter: Well, how sustainable is this diet?

>> Dr. Youdim: Over time this kind of intervention as you can imagine or this diet is not sustainable. So people will begin to reintroduce carbohydrates and therefore the weight they’ve lost often is regained. But in addition to that because of the significant intake of fat and protein rather people can develop metabolic problems like high cholesterol from that style of eating.

>> Dr. Porter: Now gluten-free I’ve certainly heard a lot about that. I think about half the non-medical people I know are following a gluten-free diet. Now just for our listeners that aren’t on one, what is gluten exactly?

>> Dr. Youdim: So, gluten is actually a protein that is found in various wheat’s, rye and barley. It is actually the protein that is found in the kernel of these grains.

>> Dr. Porter: Why are people steering away from gluten?

>> Dr. Youdim: A small subset, a very small number of individuals who have true celiac disease, which is diagnosed by blood tests and biopsies, they react to gluten. But the majority of the population does not have gluten sensitivity and does not have celiac disease. But this has become a way in which to eliminate carbohydrates from the diet. The problem with the gluten-free diet is that now a lot of snack food and packaged food are now being created to be gluten-free that have other kinds of filer that are nonnutritive, so it has no nutritional value, and really it isn’t associated with weight loss. So again a gluten-free diet has been extrapolated from celiac disease to a weight loss diet which really is not the case.

>> Dr. Porter: So, it’s sort of a way to trick yourself to follow a lower calorie diet than for most of the people who don’t have celiac disease.

>> Dr. Youdim: Well it turns out that people don’t actually end up following a lower calorie diet because they’re replacing gluten-containing products with gluten-free products that are packaged and again have no nutritional value. But somehow gluten-free diet has been associated now and become synonymous with a healthy or a weight loss and that just isn’t the case.

>> Dr. Porter: Well can you tell us about a more effective way to reduce calories?

>> Dr. Youdim: A better way of going about this perhaps is to eliminate packaged foods; processed foods many of which may or may not contain gluten and that would probably be a better way of achieving that objective of calorie restriction as well as ensuring that people are eating nutritious foods.

>> Dr. Porter:  What kind of nutritious foods would you recommend they replace those packaged foods with? I’m sure we can think of most of these but run down the list for our folks.

>> Dr. Youdim: So, I really like to give my patient’s broad strokes, and I give them anecdotes like more from the fridge less from the pantry, more from the earth less from the package. So Whole Foods is really a good way to go; lean protein, fruits and vegetables even grains, beans and legumes.

>> Dr. Porter: I’ve heard juicing has become another huge fad; does it really work?

>> Dr. Youdim: There are so many food myths out there; Myths that have somehow made it into the mainstream. One of my biggest pet peeves is juicing, so juicing has become synonymous with health and weight loss. But in fact, juicing is not a good strategy at all for health or weight loss. Juice essentially takes out the nutrients, the fiber and the health benefits of fruits and vegetables and leaves us only with the sugar. It is not a healthy way of achieving weight loss or better health. Also, keep in mind that juicing can contain up to 25 to 30 grams of sugar. That’s equivalent to the amount of sugar in a can of coke. So again we have to be careful of the foods that have kind of made their way into our healthy lexicon and recognize that juices, granola and many of these smoothies can be highly caloric, filled with sugar and not consistent with a healthy diet or a weight loss diet.

>> Dr. Porter: Another diet I’ve heard spoken of a lot is the Paleo diet. I guess that’s short for Paleolithic, which is the Stone Age, so I guess that’s the caveman diet. I presume that was good for caveman but is it good for us today?

>> Dr. Youdim: So, the Paleo diet is another type of low carbohydrate diet and essentially is recommending a lot of meat and fish, but in the case of the paleo diet we don’t restrict fruits and vegetables in the same way as recommended for the Keto diet. The paleo diet does, however, advocate for excluding dairy and grains which I don’t necessarily recommend. Again we talked about grains as a good source of carbohydrates that can be conducive to healthy weight loss. Also, they recommend eliminating dairy. There has been a lot of discussion about dairy and weight loss, and this I would say is one of the weight loss myths that you can lose weight with dairy, which is in fact not true. Dairy can be a great source of protein. For example, eggs and yogurt, which I recommend quite widely and this is eliminated in the Paleo diet as well.

>> Dr. Porter: Thanks, Adrienne. We are going to pause for a quick break.


Did you know you can check out to explore educational videos on procedures, exams, and conditions. Test your medical knowledge with quizzes, and see how you stack up against other website visitors! And you can do it all without distracting ads or sponsored content getting in the way. Now back to Dr. Porter and the Medical Myths Podcast.

>> Dr. Porter:  So, Dr. Youdim we talked about a lot of outrageous sounding diets. Do you think that adds to the credibility of the diet? Kind of like with medicine if it doesn’t taste bad it’s not going to be good for you.

>> Dr. Youdim: I do. I think people are looking for something new, looking for something different and it seems as though the more outrageous the diet, the more credible it becomes to the public. I’d like to encourage people to really fall back on their own instincts. It doesn’t have to be so difficult, and I think people really know the right way to eat. I think if people really trust their gut and their intuition they know what the right foods to incorporate are and what are the foods they need to exclude. If something sounds too good to be true, then it is probably too good to be true. Look I can appreciate people’s desire to do better and to want to lose weight and be healthier, but that desire to do better should not trump their own good judgment.

>> Dr. Porter: Now maybe one of the advantages of these kinds of branded diets, the gluten-free, the keto diet, is that they’re structured and people have something to follow that they can do and lookup and here’s how I’m going to eat. Now those may not be optimal but is there some place they can go and get information about the healthy diet that you described?

>> Dr. Youdim: So, there are various diets that have been studied for health and diets that have been looked at for weight loss. And again those two are not necessarily synonymous. The Mediterranean diet has been widely studied for its health benefits and has been shown to reduce heart disease, reduce Alzheimer’s and cognitive delay and reduces the risk of other metabolic diseases like diabetes and high cholesterol. It is a very healthy dietary plan and style of eating, but even the Mediterranean diet will not necessarily result in weight loss unless modifications are made.  So I do recommend the Mediterranean style diet, but I don’t want people to be discouraged if they don’t lose weight from following just a plain Mediterranean diet. We do have to make modifications in order to induce weight loss.

>> Dr. Porter: What can you eat on a Mediterranean diet?

>> Dr. Youdim: One of the major food groups that is included in a Mediterranean diet is nuts, oils, and seeds. Essentially the good fats and these good fats can be very heart healthy but they are ultimately fats, and if they are consumed in excess they are obviously not going to result in weight loss.

>> Dr. Porter: Right so it’s the amount you consume that’s important there, but probably that diet in smaller amounts would be effective. How can people tell how much they should be putting on their plates?

>> Dr. Youdim: I like to give people general guidelines, and some of those guidelines include first having protein with every meal. Studies show that having 20-30 grams of protein per meal is associated with a greater sense of fullness. It also is associated with less snacking later in the day as well as reduced portion sizes in the subsequent meal. Protein has other benefits in weight loss. It helps us preserve lean body mass or muscle mass, so when individuals lose weight, we’d like them to preferentially lose fat mass and not muscle. One of the ways in which we can achieve that is by consuming the 20-30 grams of protein for a meal. Another general guideline I like to give my patients is “Make half your plate green, so of course, it doesn’t have to be green but the point being that we want people to consume half their plate in fresh vegetables and even fruits. That also is a great strategy limiting portion sizes and making sure you’re getting all of the nutrients provided through fruits and vegetables

>> Dr. Porter: Should people be taking supplements if they’re following a diet?

>> Dr. Youdim: Supplements can be tricky because first of all, they are widely unregulated, so the supplements, including vitamins, minerals, and herbs that we find on the internet or over the counter are not regulated by anybody or agency. In fact, when it comes to weight loss supplements, a recent study found that over 80 % of them were what we call adulterated. In the case of weight loss supplement, in particular, I emphatically discourage people from purchasing these things from over the counter or on the internet because chances are they are going to be adulterated. Now to answer your question of whether or not people should be on vitamins and minerals; Studies do show that people who are overweight and obese are actually malnourished meaning that they don’t have the vitamin and mineral levels that they should in the body. So I think people who are overweight probably would benefit from a general multivitamin and again if people are losing weight and restricting certain categories of food, they also would benefit from a multivitamin in their diet.

>> Dr. Porter: What do you think is the reason for the emergence every couple of years of a new fad diet?

>> Dr. Youdim: People have busy lives. We are running around after our children after our parents acting as caretakers, we have busy jobs and work long hours, and this is not conducive to thinking about our nutrition. Increasingly people are looking for quick ways to get food in and quick does not necessarily mean healthy. So it is simple advice, but it is hard to follow because of the environment and the way in which we live.

>> Dr. Porter: That makes it a mental challenge as well as a physical one; can you speak a little bit to the mental side of maintaining a diet?

>> Dr. Youdim: Having these bad foods around like you mentioned really makes it difficult. There was a study that looked at free lunches in the workplace and noted that people were gaining an extra 1,000 calories from free food that was provided in the workplace. And usually these foods are not healthy, and there is a mental or cognitive component to that. We actually know that visual cues prompt people to eat more than they otherwise would and simple funny interventions like putting candy in an opaque jar as compared to a clear jar can reduce the amount of candy consumed. So it speaks to how powerful that visual cue can be.

>> Dr. Porter: Can you give me a little bit more on that?

>> Dr. Youdim: Another interesting component along those lines is the response to smells. There are researchers that talk about the pollution of smell in the environment. We all know how we feel when we walk past a bakery for example. That smell served as a cue that drives hunger.

>> Dr. Porter: Going to drive me away from a gluten-free diet that’s for sure.

>> Dr. Youdim: That’s true.

>> Dr. Porter: So, Dr. Youdim, one of the common factors in these diets that doesn’t sound so detrimental is that they have you eating protein; can you tell us about that?

>> Dr. Youdim: That’s right so protein is a very important component in a healthy weight loss plan and the reason being multifold. First of all, protein is a very satiating nutrient. Higher protein diets will actually suppress gut hormones or hunger hormones that signal hunger at the level of the brain. Our studies show that eating 20-30 grams of protein per diet will actually reduce gut hormones that signal hunger later in the day. 20-30 grams of protein can be hard to achieve, for example, a 3 ounces order of chicken or fish is on the order of 20-25 grams of protein it can be harder to achieve at breakfast time. An egg a common form of protein only has 6-7 grams of protein; cheese can provide less than that and can also be highly caloric. While it is important to get that degree of protein, it can be difficult to do.

>> Dr. Porter: In summing up could you give the three of the most important points you’d like to leave listeners with about dieting?

>> Dr. Youdim: First of all, eliminating entire food groups is not healthy. The second point that I would like to bring up is that diets that seem outrageous are outrageous most of the time. Follow your intuition and follow your instinct. The third thing people should remember is that people are different and that people will respond differently to different diets. Not all people are going to have the same results and be mindful of that.

>> Dr. Porter: A lot of good advice from our diet and nutrition expert for the Merck Manuals Dr. Adrienne Youdim and she’s also an author of content in the Merck Manuals, and we encourage anyone interested in learning more to visit and read what she has to say.

>> Dr. Youdim: I appreciate that and thanks for having me on.

>> Dr. Porter: And as we like to say here at the Merck Manuals…

>> Dr. Youdim: Medical knowledge is power; pass it on.