Five Weight Loss Myths I am Constantly Fighting


I talk to people almost every day who think they can lose weight by exercising. I tell them that is impossible. I explain that it takes almost an hour of brisk walking to burn 100 calories, which equals one apple or a ten second binge on junk food. To lose a pound a week, you need to reduce your calorie intake by about 500 per day – that would be the equivalent of five hours of moderate exercise every day. We’d have to quit our jobs to do that.


The other fallacy I hear all the time is that, somehow, adding “healthy” fruits and vegetables can make a person lose weight. I tell them that adding anything to their daily calorie intake will have the opposite effect. I more or less patiently explain that our job is to figure out what to take away instead of what to add. Maybe substituting a fruit for a Whoopie pie is healthy in other ways, but it has almost nothing to do with weight loss.


A third fallacy is that eating a healthy breakfast will ensure weight loss. To explore this one, I ask: “Are you often hungry?”

So many of my overweight patients deny ever feeling hungry – that gnawing feeling in the pit of your stomach and the low blood sugar onfusion and weakness I feel by 9 or 10 am after doing barn chores on an empty stomach (only coffee).

When I hear “I never feel hungry”, I don’t recommend starting a good breakfast habit because that would likely increase a person’s daily calorie intake. But when I hear that a breakfast skipper goes for the doughnuts mid morning due to hunger, I certainly recommend eating breakfast. When I do, I always point out that the typical American cereal and banana breakfast, along with soft drinks, is actually the major reason for our obesity and diabetes epidemics.


The fourth myth is that you somehow have to eat a certain number of meals. That depends on how you feel. If you’re in the habit of eating, say breakfast and supper and have no symptoms if you were to skip lunch, then why eat it, unless you’re trying to put on weight? The problem, again, is when a meal-skipper gets the munchies. We need to avoid that trap.


Number five is all the overweight diabetics who have been told by dieticians and diabetic educators that they must eat a certain amount of calories or carbs or number of meals just because they are diabetics. That is sometimes the case, because some diabetic medications can cause low blood sugar if you skip meals, but it is by no means a universal truth. If you want to lose weight and feel just fine not eating all the meals and snacks those people tell you to consume, why force yourself to do it? Why not listen to your body (instead of your desires or prior indoctrination)?

It is a sad state of affairs that almost everybody knows complicated things like operating their smartphone but are so lost when it comes to knowing what to eat. (We can thank the food/snack industry for that.)

51 Responses to “Five Weight Loss Myths I am Constantly Fighting”

  1. 1 DrJKH May 10, 2021 at 11:22 am

    Those aren’t all myths.

    -Board Certified Obesity Medicine Specialist

    • 2 Steven Rapp, FNP May 14, 2021 at 2:06 pm

      Can you expand on that? Which myth isn’t so mythical? I promise that is a true question not a smart quip…

      • 3 DrJKH May 17, 2021 at 10:19 am

        Expanding on that is an entire medical specialty. Go to medical school and learn medical science. Complete a primary residency and learn the practice of medicine and science. Then do the fellowship or self study in obesity medicine to earn the board certification. Contrary to what the nursing organizations tell everyone, there are no shortcuts to knowledge.

      • 4 Kirk Andrus May 18, 2021 at 10:46 am

        Ignore DrJKH his reply was condescending, quite rude and blatantly absurd.

      • 5 Laquisha Carroll May 29, 2021 at 12:34 pm

        Truly a ridiculous reply from DrJKH! It does such a disservice to patients as well. The vast majority of persons in this country don’t have access to an obesity medicine specialist (whether they are MD, DO, or NP). Going to medical school and doing a residency won’t fix that problem as those routes have few nutritional/lifestyle modification content, hence the very reason why a separate obesity training fellowship was even created. If every person who is overweight or obese had to see a specialist, his ‘specialty’ is not going to be able to handle that. The problem is too big for a specialty and has to be a part of primary care. He should be elated to share his knowledge with as many providers who want to learn because it moves us forward. But his reply shows his character that when someone asks for knowledge he chooses to reply in that manner. His ire should be towards our food/farm industry and health insurance that makes the majority of our weight loss therapies and access to nutritionists such a barrier. And FYI you don’t need to be an MD/DO to do obesity medicine training. It’s available to all independent licensed providers.

      • 6 DrJKH May 29, 2021 at 1:06 pm

        To actually understand medicine and science you need to become a physician. Period.

        And sorry, you’re STILL stuck on the old food=obesity myth. Your entire argument has no cohesion because of it. If you understood science, then you’d begin to be able to grasp the actual facts. The specialty was started because it was realized that there wasn’t enough actual science to guide us, and that the old dogma about nutrition wasn’t working.

        Typical hateful, angry reply from a midlevel. 🙄

  2. 7 John R. Dykers, Jr. MD May 10, 2021 at 2:05 pm

    You will really appreciate “Pleasure Per Calorie” just out on Amazon Kindle and Paperback. It jibes very well with your good advice. Sure you will share with patients. Also share “How To Be A Happy Former Smoker(Even if you think you don’t want to)”, and likely some new tips for you!

    • 8 DrJKH May 17, 2021 at 10:13 am

      You simply don’t know what you’re talking about. You’re just repeating failed dogma that came from the puritanical beliefs of JK Kellogg and SW Graham. Food has very little to do with obesity, diabetes, HTN, etc. Stay in your lane or learn some science. That goes for everyone on here spewing opinion based, evidence lacking statements.

      – Board Certified Obesity Medicine Specialist

      • 9 acountrydoctorwrites May 17, 2021 at 10:28 am

        “Food has very little to do with obesity, diabetes, HTN, etc.” – REALLY???

      • 10 DrJKH May 17, 2021 at 10:41 am

        Yes really. And the fact that so many people believe it does, won’t let go of the myths, and won’t embrace the science, is why we’ll continue to struggle with these problems for a LONG time.

      • 11 acountrydoctorwrites May 17, 2021 at 10:43 am

        Please post references. And, if I may ask, what do YOU eat and what is your BMI?

      • 12 DrJKH May 17, 2021 at 10:47 am

        Like I said, that’s an entire medical subspecialty. How about YOU post references for the dogma you’re repeating. Be careful not to post “references” that are just others repeating the millenia old dogma. Post actual conclusive scientific evidence.

        Your quip about me just proves you aren’t interested in the actual science.

      • 13 acountrydoctorwrites May 17, 2021 at 11:10 am

        I would love to see it and since you make such radical statements about food having nothing to do with the chronic diseases of our time, I’d think you would welcome the opportunity to cite one single source. I have done the reading I can, from Atkins to Sears to Hyman. I would love to read something with a different conclusion.

  3. 14 Tony Glaser May 15, 2021 at 9:29 pm

    I agree with all of this in general. But I don’t think it is impossible to lose weight by exercising. Running a mile consumes about 100-110 calories, and it is perfectly possible to run 5 miles a day without quitting your job – ie. over 500 calories a day, or over 3500 calories per week. I don’t expect people to do this, but some do!

  4. 17 John E Walker May 15, 2021 at 10:30 pm

    I have to say walking a mile burns about 100 calories depending on your weight. I think it would be hard to walk a speed of 1 mile per hour. So I disagree that walking an hour burns 100 calories in general.
    The author’s point is correct in that the bottom line is if you reduce your calories, in general you will lose weight. The rest is details.

  5. 18 Anuja Sharma May 15, 2021 at 10:39 pm

    I agree with all of the points and patients often feel frustrated because of their belief in these myths. I share the 80/20 rule of diet/exercise contribution to weight loss and weight maintenance. Overweight and obesity remain a problem in our times.

  6. 19 Stephen Park May 15, 2021 at 10:49 pm

    I would argue that exercise is important for weight loss, not for calories burned, but for improvement in insulin and leptin sensitivity.

  7. 20 Craig Primack MD May 16, 2021 at 12:15 am

    Just a correction. I like the tone/message of your article but a mile walked or run burns about 100 calories and the average person can walk a mile in 20 min. 300 calories an hour. Still no different in the end but surely not 5 hours a day. Thanks.

  8. 21 Dennis K-Borna May 16, 2021 at 12:45 am

    I generally agree with this, but the numbers in the first point are patently untrue. One mile of physical activity will generally burn a little over 100 calories. A moderately-paced walk is about 3 miles per hour, or slightly more, which would make a moderate walk for an hour closer to 350 calories. The general idea that food plays a much larger role than exercise in the input/output of calories is certainly true, but the specific numbers given are quite a ways off from the truth.

  9. 22 Anthony Kane MD May 16, 2021 at 2:23 am

    One of the main reasons people overeat is that it makes them feel good. A person needs a certain amount of things that make them feel good every day. Once a person gets into exercising, that also makes him feel good. This can reduce the desire to snack and overeat. In my experience, 90% of weight loss is diet. However, for many people, exercise can be the 10% that drives the 90%
    Anthony Kane MD

    • 23 Faith Phillips, DNP, FNP-BC May 17, 2021 at 6:59 pm

      Well stated, Dr. Kane. Once the patient gets past the the initial feelings of, “I think I’m going to die”, the benefits of exercise far outweigh the actual calories burned.

  10. 24 GLORIOSA R. ANTIPORDA May 16, 2021 at 5:56 am

    There is just too much cheap food in the supermarket compared to other countries!!!!

  11. 25 Alexander Nguyen MD May 16, 2021 at 11:06 am

    Agee that it’s difficult to lose weight with exercise alone, need to focus on dietary changes more so.

    However, substituting whole fruits/vegetables/grains/legumes for other calorie-dense foods/processed foods can help with satiety and weight loss. Fiber is excellent, healthy for you, and can make you feel full. Eat the whole apple, don’t drink apple juice. Consider a plant-predominant diet, whole food plant-based diet for healthy, sustainable weight loss. Minimize processed foods including processed carbs, meat, etc. Not all carbohydrates are bad (ex. whole fruits/vegetables/grains/legumes).

    Great article to start the conversation.

    • 26 acountrydoctorwrites May 16, 2021 at 11:13 am

      Personally, as a recovering vegetarian, I advocate a very low grain diet. (See my video about that.) Americans ignore the fact that grains milled into powder (flour) become glucose already in your mouth.

  12. 27 Carol Jellett May 16, 2021 at 11:58 am

    He said “whole” grains. And the concept of a Plant based, whole foods diet is that it is less calorie dense and nutrient rich. It will also improve the cholesterol profile and gut microbiome.

    • 28 acountrydoctorwrites May 16, 2021 at 12:02 pm

      A lot of people use the term whole grain for flour – unless you have to chew the grains, they are glucose in your mouth! Brown wonderbread is still wonderbread. Low carb has better outcomes data than plant based, which is poorly a defined term.

    • 29 madcat101 May 16, 2021 at 5:42 pm

      Agreed, thank you, I did say ‘whole’ grains, not processed grains/foods

  13. 30 James M Amberg May 16, 2021 at 3:05 pm

    Weight loss is nice but since so many Americans fail, it can lead to health care avoidance. “I will make that appointment after I lose 5 pounds.” Promoting good health habits like choosing healthy foods, moderate physical activity, no smoking, no or moderate alcohol, and good sleep may in the long run lead to better overall health. Sadly, no good scientific way to prove this or anyone else’s posted wisdom.

    • 31 acountrydoctorwrites May 16, 2021 at 3:08 pm

      Devil’s advocate: I read somewhere that 25% of smokers said their doctor never mentioned smoking was bad. Should we not talk about weight? If a patient expresses a desire to lose weight, should we not tell them how?

  14. 32 William Tong MD May 16, 2021 at 3:43 pm

    Form my experience:
    1. I agree that dieting is more effective than exercise. Hard to put numbers on it since every body’s metabolism is different.
    2. I also agree with Dr. Kane that exercise does seem to empower patients to further dieting.
    3. I have seen people lose weight principally with exercise but it usually involves a time consuming sport such as tennis. 3 sets and thus 3 hours less time eating. And in my own experience, after heavy exercise, I have no energy to eat; feel more like napping.
    4. But it all comes down to whether the patients can control their own eating habits. Thus if there are no metabolic problems and the patient is not grossly obese which may be better off in surgery then programs such as weight-watchers get better results, along with the primary care provider, … oh and of course the much maligned exercise. A Trifecta.

    Thank you Dr. DUVEFELT for stimulating our thoughts.

    • 33 Rick Kelly May 17, 2021 at 10:28 am

      ” it all comes down to whether the patients can control their own eating habits”
      That is a problem for all of us, I think. Modern processed and high carb foods are designed to make us crave more. Remember the Lays Potato chip ad, “No one can eat just one!”? I think hormones (insulin primarily) play a huge part in it, but others do also. I often pose the rhetorical question “why does a teenage boy eat you out of house and home?” or “why do pregnant women crave weird foods?”. It is not because of a moral failing, it is hormones.

      Rick Kelly MD

  15. 34 Margery Williams, P.A. May 17, 2021 at 8:47 am

    You also will increase your basal metabolic rate with exercise and that promotes increase calorie burning. I found that intermittent fasting promotes weight loss along with exercise. Also whole foods will increase fiber in the diet. We should strive towards 25 g of fiber a day with a minimum of 2 to 3 quarts of water to digest it. This digestion process will also burn calories.

  16. 35 Mitchell Mimier, DO May 17, 2021 at 9:26 am

    We as a society need to change our relationship with food. We have a mindset in this country that every time we eat it needs to be a gourmet meal. It doesn’t. For weight loss, find a handful of easy-to-prepare, filling/sustaining meals that you find appealing and eat those most meals of the week. Sure, go a little crazy a few nights a week to keep yourself sane. But we are constantly bombarded every day with imagery and advertisements of delicious but terrible foods. That’s like putting cocaine in the face of an addict. There’s a lot of money to be made in the American diet, so money is spent to keep it at the forefront of our thoughts. Change the mindset, be ok with a blah breakfast and lunch with appropriate macronutrients, optimize hormones, drink a lot of water, and the weight will come off.

  17. 36 Mikhail Berman May 17, 2021 at 2:32 pm

    I did practice Bariatric Medicine for a while and found out that most programs utilize appetite suppresants such as phentermine or bupropion or others and as soon as you need to discontinue them after 6-8 weeks weight gain starts.
    I think that most people are unable to loose weight for several reasons.
    1. They wait till they are really hungry, which usually is late in the everning and then indulge while eating very hungrily and fast. This will enable them to eat much more food than needed to achieve a state of satisfaction, which in general takes 20 minutes. By eating restaurant style serving instead of family style and eating slowly, starting with salad and a glass of water.
    They need to make sure to give 3-4 hours after dinner before retiring to sleep because release of GH which moves fatty acids into blood stream to be used as energy is triggered by hypoglycemia. Elevated insulin at night will instead slow the release of fatty acids.
    2. They need avoid sugars, even fruit, and starches ( everything made of grains including rice and corn and any vegetables that grow under ground e.g potatoes, yukka, etc.) and mostly eat colored vegetables: tomatoes, eggplant, cruciferous etc. Obese people have increased level of insuling which not only increases the conversion of sugars into fats, but also impairs release of fatty acids from adipose tissues into blood stream.
    3. By eating 3-4 meals ( greens and meats of course)every 4 hours or so will keep obese people from being hungry.
    Of course thyroid function has to be optimal, sex hormones balanced.
    The notion that exercise does not work for weight loss will only discourage obese people from even trying to exercise. There are other benefits of exercise except weight loss.
    My question for “board certified obesity medicine specialist”:
    Why do you have such a condescending attitude while having such dismal results of treating obesity?

    • 37 DrJKH May 17, 2021 at 6:30 pm

      I neither have a condescending attitude, nor do I have dismal results in treating obesity and its comorbidities. Not sure where you got either of these ideas, especially the latter. I do have disdain for people who continue to regurgitate the old myths as though they’re legitimize, and ignore the science that they’ve never learned, which is what most people are doing here. You’re the only one who’s made any sense, as your reason #2 is on the right track.

      • 38 acountrydoctorwrites May 17, 2021 at 6:35 pm

        I think this discussion is going around in circles. As far as I know, the prevailing belief/theory is that exercise and low fat (=high carb) diets are the way to go and some voices in the wilderness say that this theory is flawed. I, for one, am still waiting to hear from you, dear colleague, if there is a central idea you support or if it really doesn’t matter what people eat in terms of what happens to weight, diabetes, heart or autoimmune diseases.

  18. 39 DrC May 17, 2021 at 10:04 pm

    I agree the best way to lose weight is reducing calories. When I educate and help my patients, I also want them to be healthy both physically and mentally. Exercise is part of that. Just walking 20 minutes a day helps cardiovascular system as well as the mental system especially if you do it with a partner.

  19. 40 Karen Moore May 18, 2021 at 12:12 am

    And so how do you and your patients lose weight? You have left us all hanging.

  20. 42 Hector Arreaza May 20, 2021 at 9:59 am

    Calories are not just calories. 100 calories of ice cream is not the same as 100 calories of zucchini. The metabolic result of foods is different depending on the composition of the foods and not on the amount of calories they have.

    • 43 Kurt Reyes May 22, 2021 at 11:48 am

      In my obesity medicine practice, I often tell patients we go for weight control. We are the long term solution that does include weight loss. I train patients about the four principles of obesity medicine (medications, nutrition, exercise, and self monitoring). We have helped 400 patients lose 9400+ pounds over 3 years. The article reflects is misunderstanding of the principles of obesity medicine and does not recognize the change of the set point of appetite suppression that occurs in this disease. In short, the cravings that come with weight loss are the disease which is why long-term appetite suppression is needed.

      As one of the physicians replied,to address what is wrong in this article is beyond this forum/ medium and requires training. I encourage those physicians who are interested in medical weight control to become boarded in obesity medicine. Just like any other disease and treatment, study, train, and then practice it.

      I absolutely love watching patients become healthier…younger appearing, putting diabetes and hypertension into remission, and improving their lives. Join the fight against obesity.

      • 44 Laquisha Carroll May 29, 2021 at 12:49 pm

        Once again. This problem is past the capacity of a sub specialty to handle. It needs to be part of all basic medical and nurse training, with the advanced portions/pharmaco interventions included in APN/PA courses, plus tailored to persons already practicing primary care, and any independently licensed provider who wants to learn. Period.

      • 45 DrJKH May 29, 2021 at 1:01 pm


  21. 46 Michael Geer May 22, 2021 at 1:02 pm

    I don’t think that is all true. Replacing nutrient dense foods with calorie dense foods is the corner stone of obesity issues. Fiber is the unrecognized champion of weight management. Fibers only found in plants.

  22. 47 Just another mid-level (Steven Rapp, FNP) May 30, 2021 at 1:16 am

    Well I’m surprised you even gave the effort to respond to such a lowly mid-level, hanging around with the other vermin of society. You learned from someone, sometime, as sharing knowledge is an inherent part of the oath to first do no harm. By withholding your “secrets” to obesity and weight loss, maybe many of our patients (the collective our for everyone else in this group, perhaps spare the other “bored certified obesity medicine specialist”) will suffer worse outcomes rather than live healthier, better lives. I wasn’t asking for your years of wisdom and hard work to be paraphrased; simply a “#3 and #5 were verdad” or something similar. Your response took much more time and contempt than was required or requested. Some just never play well with others.

  23. 48 MARY VANKO MD June 2, 2021 at 3:16 am

    I do weight loss in my OB GYN practice. It is not ok to gain 30 pounds with each pregnancy and not lose it.

    Recommended tactics:

    intermittent fasting and daily exercise
    1200 ADA diet found on the Lilly Diabetes site

    download an app to track calories, carbs protein and fat

    There is a role for weight loss meds including generic topamax used off label.

  24. 49 Matthew Collins August 25, 2021 at 9:35 am

    This post focuses on the arithmetic of weight loss and weight gain but not much on the psychology. Hunger can trigger a PTSD reaction in some people. Excess weight can make some people feel safe. There is so much going on beneath the surface.

    I do appreciate all the input from medical professionals. It is hard to know what to believe sometimes, especially around protein vs complex carbs. There does seem to be a consensus on several points – (1) water is the ideal beverage; (2) vegetables are really good for you ; (3) added sugar and refined carbs are really bad for you; (4) saturated fat is bad for you.

    I do exercise regularly and find it makes me much more likely to eat healthy, because I know how much time and effort it takes to burn off the calories. I also enjoy it.

    I also avoid certain substances like chocolate that I have never been able to consume in moderation.

  25. 50 foggysunset May 12, 2022 at 12:35 pm

    Dr Duvefelt, I’ve always enjoyed your thought-provoking posts, as well as your books. I’m coming across this one belatedly; I appreciate the comment by Matthew Collins as I think effective weight loss counseling is as much about motivational interviewing as it is about didactic “this is what you need to do.”

    However, I’m sorry to see that as moderator you don’t disallow NP/PA-mocking non-specialist-MD-mocking comments by the likes of JKH, who freely admits to his “disdain” yet denies his condescension. His self-righteous judgmental attitude truly represents the worst I’ve seen in my over quarter century in primary care.

    Unless open disrespect of colleagues aka hate speech is removed via moderation, I’ll stop reading & participating in these comment threads.

    • 51 acountrydoctorwrites May 12, 2022 at 1:09 pm

      I think in the future I will do exactly what you suggested. There were many responses discrediting the person who did the bashing. I will work to keep my platform free from such things in the future. I have not moderated much before.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

Osler said “Listen to your patient, he is telling you the diagnosis”. Duvefelt says “Listen to your patient, he is telling you what kind of doctor he needs you to be”.



Error: Twitter did not respond. Please wait a few minutes and refresh this page.

Top 25 Doctor Blogs Award

Doctor Blogs

Enter your email address to subscribe to this blog and receive notifications of new posts by email.


contact @
Bookmark and Share
© A Country Doctor Writes, LLC 2008-2022 Unauthorized use and/or duplication of this material without express and written permission is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given.

%d bloggers like this: