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Weight Loss: Fact and Fiction – What Works and What Doesn’t

Weight Loss: Fact and Fiction – What Works and What Doesn’t

Does sex really count as exercise?  Should you set conservative weight loss goals of 5-10 pounds instead of 50?  Does adding a little bit of exercise regularly over a long period of time really add up to significant weight loss?

A recent analysis of weight loss research by The New England Journal of Medicine, entitled Myths, Presumptions, and Facts about Obesity, attempts to answer these questions.

Some findings are surprising, some are not, and some common notions about weight loss are yet to be proven or disproven. I have my own opinions based on treating tens of thousands of patients over many decades.

We are all different. What works for some may not work for all, which is why I practice personalized lifestyle medicine, or functional medicine, that  allows me to discover the root causes of imbalances in the body that lead to weight gain and disease  – matching the treatment to the person.

The good news for me is that I was not surprised by the myths that are commonly held by doctors, nutritionists, and most people.  And I know that some of the presumptions will turn out to be true – we just don’t have enough data to “prove” it.

Remember, the absence of evidence is not the evidence of absence.  Just because something has not been studied accurately does not make it untrue.

So what are the top myths and facts about obesity and weight loss?

Myth #1:  If you make small changes in your lifestyle over the long term you will lose weight.

Most of us have learned that if we just cut our calories by 100 calories a day, or increase our exercise a little bit over the long haul, we will lose weight.  It’s all about the calories in or the calories out.

Sorry Mr. Newton, your laws of thermodynamics don’t apply in living systems.  Biology and metabolism are more complex.  If we just go with the math and burn an extra 100 calories a day by walking one mile or consume 100 calories less in 35 days, you would lose one pound (3500 calories = 1 pound).

And over five years you would lose 50 pounds. Yet, in studies they find you would lose only 10 pounds in five years.  This occurs because of changes in your metabolism and calorie needs as you lose weight.

Bottom line:  Big changes are needed to create big weight loss.

Myth #2:  Don’t set big weight loss goals because you will become frustrated and set yourself up for failure.

The fact is that if you set your sights on big weight loss, you have a better chance of losing a significant amount of weight than if you keep your goals “realistic”.  If you want to lose 50 pounds, then set that as your goal.

Studies have shown that if you don’t expect to lose a lot of weight, then you won’t!  Common sense, it seems, but conventional wisdom is to keep people’s expectations low because weight loss is hard and people will get frustrated if they fail to achieve their goals.  The truth is that you will only lose big if you think big.

Bottom line:  Set your weight loss goals high.  Don’t be realistic. If you set 10 pounds as your goal you might succeed, but if you need to lose 50 pounds you will fail. If you want or need to lose 50 or 100 pounds then name it. Own it.  And you will lose it!

Myth #3:  Don’t lose weight too fast or you will rebound and gain it all back.    

We have been taught that if you go for the quick fix, if you go for the rapid weight loss strategy, in the long run you won’t lose as much as if you go for the slow gradual approach.


Studies show that if you drop weight quickly you end up with more weight loss in the end.  Mark Twain said, “The problem with common sense is that it is not too common.”

When I give my patients a big jump-start with weight loss, which is how I have designed my practice and my programs like The Blood Sugar Solution, they do better and lose more weight over the long run.  They learn how to own their bodies and feel empowered.  The studies back this up.

Bottom line:  Kick-start significant weight loss with dramatic shifts in your diet.  Try things like cutting out all sugar, flour, and processed food.  You can follow the program I have created in The Blood Sugar Solution.

Myth #4:  You have to be ready to succeed and go through the “stages of behavior change”.

The science tells us that those who attempt weight loss without feeling ready still succeed.  You can act into the feeling instead of waiting for the feeling to act.  

Bottom line: Even if you don’t feel inspired, excited, or motivated to start taking care of yourself, just start anyway.  You are just as likely to succeed as someone highly motivated.

Myth #5:  Sex is good exercise.

Somewhere we all got the idea that sex was good exercise.  A bout of sexual activity burns 100-300 calories for each participant.  That reminds me of a young teenage patient I saw when I was a resident.  I asked her if she was sexually active.  She said, “No, I just lie there.”

But even if you don’t just lie there, a vigorous love-making episode usually lasts about six minutes and burns about 21 calories.  If you just sat and watched TV you would burn 14 calories.   So find some other way to exercise or study tantric sex and make love for an hour.

Bottom line:  You can’t “love” your way to weight loss.  Get out of bed and start moving.

The article also had a few presumptions, which may or may not be true and still don’t have enough evidence to firmly put them in the fact category.  However, a few of them I do think are crucial for weight loss.

The Value of Breakfast

In the large weight registry of people who lost 70 pounds or more and kept it off for 4 or more years, the only things they had in common were breakfast and regular exercise.    It is one of the most powerful strategies.  But it can’t be a muffin and a latte. The secret is a protein breakfast, which speeds metabolism and controls appetite.

Eating Fruits and Vegetables

If you eat more fruits and vegetables you will be eating less junk and creating health through hundreds of other mechanisms.  In fact the only thing all nutrition experts agree on is that we should eat more fruits and vegetables.

Built Environment and Obesity

While it hasn’t been proven that more parks and sidewalks lead to a skinnier population, we do know that your immediate environment plays a big role in your health.   Dan Buettner did an experiment in Albert Lea, MN where he implemented changes in the environment that led to significant weight loss and health.

Kids lost 10 percent of their body weight after eating in classrooms and hallways was outlawed.  And the town’s population lost a total of 12,000 pounds by everyone agreeing to eat their meals using 10 inch plates and having grocers put healthy foods at the check-out counters.  Your environment does matter.

The good news from this article is we can lose weight, but we have to set big goals, think big, act big, and we will get big results!

Get started today!  Get your copy of The Blood Sugar Solution Cookbook  today.  When you purchase this book from this link you will gain access to these exclusive Dr. Hyman bonuses:

  • 1-Week Gluten-Free Meal Plan – Maps out a full week of breakfasts, lunches and dinners PLUS all new recipes for these.
  • Access to Dr. Hymans Kitchen Videos – Including cooking demos, Fridge and Pantry makeover, supermarket shopping tips and more.  Over 60 minutes of footage.
  • You will be invited to a live online presentation hosted by Dr. Hyman on March 27th, 2013.

Click here to learn more.

Please leave your thoughts by adding a comment below – but remember, we can’t offer personal medical advice online, so be sure to limit your comments to those about taking back our health!

To your good health,

Mark Hyman, MD

Mark Hyman MD is the Medical Director at Cleveland Clinic’s Center for Functional Medicine, the Founder of The UltraWellness Center, and a ten-time #1 New York Times Bestselling author.

Comments (37)

  • Great article Dr. Hyman! Very informative information! I love how you always keep things so real. I am looking forward to the next 90 days in your Beta Testing! Thank you for all that you do for us!

  • Dr. Hyman, I love the Blood Sugar Solution! After years of little or no success losing weight, I’m in week 6 of the advanced plan and I’ve lost 11 pounds and feel wonderful.
    I purchased the Blood Sugar Solution cookbook, but I found that some of its messages conflict with yours–ideas like its ok to use artificial sweeteners. Whats up with that?

    • Hi Susan!

      Are you talking about Dr Hyman’s new cookbook? If so, he advises to avoid ALL artificial sweeteners. Let us know what you are referring to so we can help clarify it! Thank you!

      For more personalized nutrition advice, Dr Hyman’s nutrition coaching team would be happy to work with you on an individual level to help you reach your goals. To work with the nutrition coaching team please go to: OR call (800) 892-1443 to get started.

  • Dr. Hyman — very insightful article on myths surrounding weight loss — it makes me wonder what other myths there are “out there” that most of us believe are true? (not only in the field of nutrition!)(Tantric yoga philosophy recommends that one keep a skeptical mind set in all things & continually makes one’s own analysis)

  • If you have sex while watching TV will that burn 35 calories? Ha!

    Thanks for another great artcile I read every single one you send and look forward to them.

  • Hi Dr. Hyman,

    For about 30 years, I have longed for functional medicine to emerge, and I am so grateful for your leadership and important contributions on this front. I especially appreciate that you work to address health at the system level, the population level, and the individual level.

    I really appreciate your efforts to make health information available online. My desire for gastronomic freedom while still living a healthy life, however, always leaves me wanting more information – provided with a little more nuance and detail. For example, you recommend eliminating dairy products from one’s diet, and adhering to this has helped me a lot. But it would be helpful to know, for example, if lactose-free milk is an option. What about products that just have whey in them? Many people tell me goats’ and sheeps’ milk products are safer – is this true? And are yogurt or kefir options? Are their components of milk lurking in cosmetics and lotions that should be avoided? It would also be helpful to know more about ‘why’ some dairy might be better than others (or ‘why not’ if that’s the case).

    You get the idea… While I’m curious about the dairy questions above, I’m eager on a whole range of topics to have more in-depth knowledge (both descriptive and explanatory) so I can apply it with more freedom in my life. I also love being armed with this kind of information so I can share effectively in my personal networks and help others understand and benefit from function medicine. In conversation, my friends and family routinely ask wonderfully curious questions, and I’d love to be better at engaging them with richer information. I hope you can help.

    Thanks again, especially for your recent books. They’ve helped a lot.


  • Dear Mark,

    Please do not make generalizations. I may not be a comfortable doctor with a financial incentive to give “advice”, but as a FUNCTIONAL nutritionist and exercise specialist, I have assisted many persons to heal themselves with the only assistance from a “medical” doctor being lab tests….


    • Dr. Hyman is right on the money. He recognizes our metabolic differences and the complexity of our bodies but reminds us to move forward more BOLDLY. Small changes are necessary too, but the big changes happen when we take big steps…imagine needing to rehydrate your body, but only allowing yourself one tiny sip. It’s better than nothing, but won’t rehydrate you either! Planting a few seeds will feed you for a day or so, but planning and planting a complete garden will feed you for months. You get the idea…:)

      I say “Be BOLD, Be HEALTHY!”

  • I’ve been dieting all 75 years of my life – starting at 6 months of age. (Dr’s orders) – and what you have stated above is ALL TRUE!!! I especially liked the “Think Big”statement. A close friend talks incessantly about losing weight – always says “2 lbs. a week is my goal”. She has gained 40 lbs. over the last 6 years.

  • Another informative article! Thank you.
    Why are so many people stuck in these myths? The diet industry and food manufacturers have brainwashed everyone into actually believing the hype. Especially around wheat as a health food.

  • Thank you Dr. Hyman for another great article!

    I think setting BIG goals applies to everything we do in life, not just diet and exercise.

    Generally, we tend to underestimate ourselves, not fully trusting in our ability to do amazing things and accomplish what we dream of.

    Always shoot for the stars; everything is doable if you want it bad enough 🙂

  • What do you think about Intermittent Fasting? Going for 24 hours, twice a week without food? Or missing breakfast each day and having 16 hours food-free each day?

    • Hi Catherine,

      Dr Hyman does not suggest eating in this cycle. He recommends allowing your body to find balance through rhythm and a diet of real, fresh, whole foods. To learn more about his specific recommendations for maintaining sustainable diet lifestyles, please see

      For more personalized nutrition advice, Dr Hyman’s nutrition coaching team would be happy to work with you on an individual level to help you reach your goals. To work with the nutrition coaching team please go to: OR call (800) 892-1443 to get started.

  • 1.On page 326 in the BSS you have a recipe for Honey Almond spread which uses honey. On the diet honey is out I have been on the diet for 0ver 5 weeks doing well. However am eating that snack. Am I shooting myself in the foot or is it OK.

    2.Am planning to reduce some of the supplements. In one of your articles you wrote that PGX plus a mulitvitamin would work. Is that so for someone who hopes to be able to go off her diabetes medican when I see the Dr. in two weeks. Will stay on the diet until I see her. Thank you, I tell everybody about the book,it has been helpfull and I feel in good health.

  • Brilliant article Dr Hyman, I will make sure to follow these rules and will give you some hopefully positive feedback soon.

    Many Thanks

  • I just wanted to thank you Doc. for all your great advise.I glean much from your wealth of information

    Many Blessings!!!!

  • Since I started reading the blood sugar solution I’ve lost 15 pounds I’ve been walking 4-1/2 miles a day. I will increase speed and soon be a runner. 45 more pounds to go and I will do it! I am so glad my doctor recommend I read your book thank you

  • Great reminder to treat weightloss as I treat other goals. I intend remind and let myself lose the weight I need to lose and promise to treat my body well with whole foods, water, and good nutrition so it can do its job. So far so good, down 38 lbs in 3 wks following your detox plan!

  • This is great advise I am glad I check back here often.
    if done right I definitly think sex should be considered excercise

  • Fantastic post, very informative. I wonder why the other specialists of this sector do not understand this. You must continue your writing. I’m sure, you’ve a huge readers’ base already!|What’s Taking place i’m new to this, I stumbled upon this I have discovered It absolutely useful and it has helped me out loads. I hope to contribute & help different users like its aided me. Great job.

    • Hi Angie,

      Moderate intake of low glycemic fruit can be part of a tasty and successful weight management program. Have you seen Dr Hyman’s The Blood Sugar Solution book? He lists examples of the best fruits (and foods in general!) to eat to burn fat and sustain normal blood sugars to keep weight off for good. Check it out!

      For more personalized nutrition advice, Dr Hyman’s nutrition coaching team would be happy to work with you on an individual level to help you reach your goals. To work with the nutrition coaching team please go to: OR call (800) 892-1443 to get started.

  • Is it true that imbalance of hormones can effect loosing weight! I’ve been doing cross fit training! I know it gives muscles and adding 5 lbs to lower half of my body but can’t lose weight! Legs and butt are heavy and I don’t feel great about that

    • Hi Linda,

      Thank you for your message and your interest in Dr. Hyman’s work. Your question cannot be answered in a responsible manner via the Internet.

      Wishing You the Best of Health!

      Dr. Hyman Staff

  • I have been on Phase 1 of the Ultrametabolism diet for 3 weeks now. The first week I lost 4 pounds and have not lost an ounce since. Any thoughts? I’m concerned that my body thinks I’m starving although I have been eating the meals recommended in the book.

    • Hi Kathy,

      Thank you for sharing your experience with The Ultrametabolism program. How are your portion sizes? Are you eating enough protein? Dr Hyman has a nutrition coaching service which is meant for exactly these types of questions. You can receive personalized advice to help you get the results you want. For more personalized nutrition advice, Dr Hyman’s nutrition coaching team would be happy to work with you on an individual level to help you reach your goals. To work with the nutrition coaching team please go to: OR call (800) 892-1443 to get started.

  • Many excellent tips here.

    I use to skip breakfast thinking it would help me lose weight. The only thing is, by 11 am I was tucking into my second cinnamon roll. Never lost weight, just put it on.

    Now, I eat a bowl of porridge, with banana, ground flaxseeds, and cinnamon sprinkled on top. This is full of fiber and keeps me going until lunch time. I’ve never had a problem with snacking before lunch since taking this.

    So don’t miss your breakfast unless its a milky latte and muffin!

  • Really it is very useful post & I like to read these types of post & thanks for sharing such type of posts…

  • I would like you to keep up the good work.You know how to make your post understandable for most of the people.

  • Great post. Such a good reminder. People who need to lose weight must understand that weight loss is already a reward in itself. Boot Camp Brisbane is one of the best avenues to lose weight. You will be surrounded with people who not only have the same goal as you do, but are also doing what you’re doing and working just as hard as you. Check us out at

  • I’ve been really hearing this a lot even from nurses, it’s just now that I’ve learned that it isn’t true. I really find it funny how you wrote “you cant love your way to weight loss, get out of bed and start moving”

  • Hey there, You have performed a great job. I will certainly digg it and individually suggest to my friends. I am confident they will be benefited from this website.

  • Thanks for sharing such a valuable information. It will help the people who want to lose weight in natural way. Most of the people looking to lose weight but majority of the people unable to achieve their targets. This is because not control on their diet and even they don’t know what to eat and what not to eat. This blog gives the clear picture about weight loss myths. The people who are having weight issues follow these tips and I hope these tips help them to lose weight. I liked the statement “set big goals, think big, act big and get big results”. It sounds awesome.

  • Hello Dr Mark Hyman….. I can’t stop myself without saying thanks for your informative article. Your article might vanish many weight loss myths to so many of us. Really it’s awesome, thanks for providing such a valid article. Please keep in touch with us and please keep sharing your tips regarding weight loss.

  • Lessons learned from my own weight loss journey:

    Set a big long-term goal but don’t expect big results quickly. Initial rapid weight loss is going to be water weight.

    The weight you want to lose is fat. Healthy fat loss is about 1 pound per week, on average– maybe slightly more in the beginning, but less as you go. If 3500 calories = 1 pound of fat, then through diet and exercise there must be a 500-calorie deficit per day all seven days a week to lose 1 pound of fat. A 50-lb fat loss in one year is a fantastic accomplishment.

    Eliminating carbs completely will slow down your metabolic rate. Ketone metabolism is slower than glucose metabolism. Healthy carbohydrates consumed strategically (prior to exercise) get burned off during exercise, then fat is burned afterwards. (The afterburn effect.) Protein is best consumed after exercise, as that is when the body needs amino acids to rebuild muscle tissue.

    Not mentioned in this article but hugely important for weight loss are probiotics. The mechanism for this is not yet understood, but likely has to do with how dietary sugars are processed by the body. “Diabesity” is most certainly influenced by the types of gut bacteria present. This could explain why two people who consume similar diets and have similar activity levels, but one is fat and the other one is skinny. We all know someone who eats whatever they want and remains thin, and we all know someone who diets like mad and can’t seem to lose any weight. The answer may be in the type of gut bacteria each has.

    Diet is far more important than exercise for weight loss. In fact, heavy people are more likely to sustain injuries by trying to exercise too hard and too fast. With exercise, the focus should be on finding something that is not too difficult and is enjoyable, so that you will continue to do it. Just going for walks is enough to get started. For some people, even that can be challenging. When I was fat, I remember thinking how much easier exercise would be if I wasn’t so fat. The key is to find something fun and not to push yourself too hard at first. Once you are used to it and have made daily exercise a habit, then you can focus more on improving your performance.

    Doing a liver cleanse can help greatly with weight loss. All fat burning goes through the liver. If your liver is burdened with toxins (alcohol, chemical additives in foods, prescription drugs, polluted air and water, etc.) it will not be as efficient at converting fat into energy that the body can use. Eating an organic, whole-food diet and maintaining adequate hydration by drinking enough pure water will help your liver do its job most effectively.

    I lost 50 pounds in one year, and it was easy. By eating more nutrient-dense foods and eliminating junky processed foods and fast foods I found that I did not want to eat as much, so naturally consumed fewer calories without feeling hungry. I minimized watching TV to avoid being bombarded with junk food advertising and I made a commitment not to eat at restaurants until I achieved my weight loss goal. Now I find that I really don’t want to eat at restaurants anymore because their food offerings are just not as appealing to me as they used to be.

    By implementing the above changes I was able to transition from an unhealthy lifestyle to a healthy one. It was not as difficult nor as unpleasant as I thought it would be; it was actually quite refreshing. My reward is looking and feeling so much better. I think anyone can do it. You just have to tune out the advertising and focus on the new you.

  • I really like how much work went into this post. I also feel that you are right cutting carbs and calories with some light exercise can really go along ways. The problem is is that for some people this doesn’t work fast enough for them, so they look for other ways to boost their weight loss..and some products do work in order to aid the process of weight loss.