Why do I get constipated or not lose weight on green smoothies? Part 1 of 2

This is Chris, the GSG webmaster. Robyn has been in Michigan for a week and I have been posting her blogs. I accidentally posted part 2 yesterday without part 1. I remedy that here:

Dear GreenSmoothieGirl: I’m drinking green smoothies, and you said they were low calorie, high nutrition! Why have I GAINED two pounds in the last two weeks?

Answer: Most people quickly LOSE weight on green smoothies, and most people’s digestion improves, in my research. (Discussed in depth in The Green Smoothies Diet.) Logic bears that out, since drinking so much volume, of only 200 calories, bumps out other food that is invariably higher calorie. And green smoothies are so high in fiber that digestion should improve. Keeping all other things constant, simple physics DEMAND that you are increasing your metabolism in many ways, you are burning fat, and you WILL lose weight. Note that the sentence began, “KEEPING ALL OTHER THINGS CONSTANT.”

(I don’t want to insult anyone’s intelligence, so forgive me for this. Hopefully it goes without saying, that if you’re increasing your consumption of junk food, because you feel that your new green smoothie habit justifies it, that could be why you’re not losing weight. That’s all, on that topic.)

However, as 175 people in my initial study radically changed their nutrition with the green smoothie habit, these were fairly common reactions within the 18% who experienced a negative initial reaction:

Bloating, constipation, not losing weight

Why does this happen? First of all, anytime you change anything, there are always a number of consequences (some more noticeable than others). Hundreds of things are changing in your body. It is receiving nutrition it has needed from the beginning, but as you begin supplying it, you may notice fits and starts, hiccups and burps and discomfort.

All the new fiber is supposed to act as a broom, sweeping the intestines and colon. However, what happens when, in addition to lots of that, the colon begins loosening and releasing hardened material that has perhaps been there a long time?

The colon can get backed up. There’s over 30 feet of intestines and colon, and often when you’ve been eating the S.A.D., peristaltic action has slowed and become very sluggish. You can perk it up over time by clearing it out and feeding it high-fiber food at EVERY meal and snack.

Your kidneys can get backed up. (Do this for a couple of decades and you’ll need a kidney transplant.) Your liver can get backed up. (Ever seen anyone whose eyeballs are yellow?) The lymph system can get backed up. (Your neck has big, bulging, painful nodes.) The tonsils get backed up. (Doctors say, take them out! They are, in fact, yet another organ of elimination, little understood.)

The heart and arteries can get backed up (this is what ambulances were built for). The skin gets backed up (four letters: Z-I-T-S). Need I say more? We could go on for paragraphs. The parts of your body that aren’t holding things together, and building/repairing, and locomoting you? They’re detoxing you.

I know I’m grossly oversimplifying. But your colon is the most obvious, simple organ of elimination, and the toxic fuel you choose is 90% of why every single one of these organs gets weak, and gets sluggish, and THEN…..when the miracle happens that you change fuels, they get backed up.

This can happen within days of starting green smoothies, or at any point down the line. You didn’t get in the shape you’re in, in two weeks, and it’s going to take you longer than two weeks to truly “clean house.”

Read part 2 here


30 thoughts on “Why do I get constipated or not lose weight on green smoothies? Part 1 of 2

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  1. Thanks for this article!

    I have just re-started green smoothies and my face is breaking out horribly. It’s something I have had trouble with before, though I am in my 30s, but it has gotten worse since restarting my smoothies.

    Now I know why!

    Thanks for the reassurance. 🙂

  2. I’m asking this question to help a friend of mine. I was so excited about green smoothies that I got her into them, but now she’s thinking that maybe her body is “different” and they’re not good for her. She drinks smoothie in the morning (just 16 oz or so) and the rest of the day feels so bloated that she’s not hungry. And she probably only puts about a quarter pound (or less, just starting out) of greens in her blender. She’s at the point now where she feels like this most of the time no matter what she eats. She had a colonoscopy done about a year ago, only to be told she’s fine. Does anyone know how long it could take for her body to not be “backed up”? Do you think she just needs to do a cleanse? If so, which one? I’ve heard of some that are shorter term and affordable. Thanks for the help, I don’t want her to give up on green smoothies!!!

    1. Britni, it’s common to have that detox reaction. She needs some pretty significant education; give her my starter book, The Green Smoothies Diet? She may have a more significant problem of some food sensitivities, which will just get worse until she starts addressing the nutrition her body needs. Unfortunately, people don’t always do it just because we want them to!

      1. If it’s food sensitivities, and it likely is, then it will get worse until she figures out what they are and remove them from the diet or find another way of prepping it that won’t cause constipation/symptoms. Simply addressing nutrition will not overcome this. There are food intolerances to just about every food imaginable, including nutritious foods like cruciferous vegetables.
        Some people can’t eat raw veggies and that includes those in smoothies.

        Oatmeal is a very severe food intolerance for me, even when it’s steel cut oats and cooked with prunes, doesn’t matter what I cook it with or how long I cooked it, it always constipated me. And I tried different kinds of oats. Turns out I have selective grain sensitivities and nothing, AND I MEAN NOTHING, NOT EVEN CLEAN EATING, NOT EVEN COLONICS (and I’ve been to 3 hydrotherapy clinics), works for as long as I’m eating simmered grains. I only began to see relief when I stopped eating oatmeal, millet, etc.

        Finally, everybody’s body is different and there are bodies that just won’t respond well to smoothies even if they did everything right.

        To work out which foods are causing symptoms, I recommend food to symptom tracker apps. The best apps to date I found for this are MySymptoms and Symple-Symptoms. I’m using MySymptoms myself.

        1. true that food sensitivities are an issue for many. not true that addressing diet, over a significant period of time, can’t turn food sensitivities (to good foods) around. in fact, for many, those food sensitivities are constantly shifting. and, rebuilding gut is key to the body NOT attacking itself once it is healed. being reactive to good foods (like simmered non-gluten grains) is indicative of needing some gut healing….we always suggest learning cultured foods, like in our 12 steps to whole foods course, step 8, trying several of those habits from around the world. everything changed when i rebuilt the healthy flora in my gut. avoiding antibiotics, avoid gmo and processed foods and allergens, while getting lots of good nutrition and especially eating homemade cultured foods, really does work. the body is not meant to be highly reactive to whole foods and this, as well as many diseases and symptoms, the body DOES know how to heal from. we aren’t teaching that “smoothies” are what heals us…..we’re teaching a far broader message than that. GREEN smoothies are just one way to get a lot of greens, superfoods, even a cultured-foods base, in the diet, pretty easily.

  3. Some people cannot lose weight because of thyroid problems. It doesn’t matter what you even if you eat a raw diet. I struggle. With hoshimotos disease Which causes my thyroid to fluctuate from exteme high to lows. If you can’t lose the weight and are.eating as you should. You might get want to get your thyroid levels checked.

  4. Robyn,

    I just watched your video of all the rejections you got for the green smoothie at the SLC airport. You need to package it differently. I wouldn’t take a drink of something that someone else had drank out of and had their straw in the bottle. But I would take a drink if something were poured from a bottle into a little cup (and the person giving it to me poured some in a separate cup and drank first 🙂 We live in a suspicious world. I like green smoothies and drink them all the time. But I have to say I also would have rejected your offer at the airport even though I know what green smoothies are all about. Just saying…..

  5. I have been doing green smoothies for 8 months now. Total diet change, but, of course, I do eat other solids of healthy foods.

    But, I am totally discouraged, and confused, I went in excited to have a cholestrol check on the new diet, and to my amazement, my total cholesterol is HIGHER than it has ever been.

    What is your thinking on this? Is there a specific combination of fruits/veggies that I should be doing, rather than just random combinations?

    Thanks for your input.


  6. I’ve gotten bloated by drinking a smoothie too fast. I have to slow down and then it’s not a problem.

    I add a little bit of Udo oil, essential omega 3/6/& 9. No constipation & I’m getting “essential oils”.

  7. hi Robyn:

    My question to you is that I have Hashimoto’s Thyroiditis. Won’t green smoothies aggravate my condition because of all the raw greens? Any info you can give me would be great.



    1. Yvonne, I can’t advise people about specific medical conditions. I was hypothyroid and greens did very well for me. Many compounds in greens are NURTURING to the thyroid. You will have to consult with your practitioner; hopefully you have one who understands the complex interplay of systems in the body, rather than an M.D. specialist who operates exclusively in drug approaches that don’t heal anything.

  8. Hi Robyn,

    I have been on green smoothies and 70% raw food, vegetarian diet for over 2 years now. I am on gluten, casein and eggs free diet as well due to sensitivities. I feel very good overall and many health issues I have had are gone or improved tremendously. There is one thing however that I have difficulty managing and that is my blood iron. My Ferrum was at 16 in April and dropped down to 6 this month. My GP prescribed me FaraMax 150 that is not supposed to cause constipation and I take it every other day. Constipation and hemorrhoids, the problem I had since childhood, is a reoccurring issue and I am wondering if and how this might be impacting my iron absorption. I am often constipated even if I don’t take iron supplements; I have 1 bowel movement per day. Thank you in advance for taking the time to respond.


    1. Alexandra, I’m always a fan of getting iron from foods rather than pills that aren’t very bioavailable and can in fact be harmful. Prunes, greens, whole grains, etc. are rich sources of iron; however, you should also convert to a whole-foods diet in general to improve, over time, your mineral absorption overall. You can get it all but if your body isn’t using it, it does you little good.

  9. Hi Robyn,

    Thank you for your reply; I have been on whole foods for over 2 years. As a matter of fact I mostly use recipes from your 12 Steps Book when I am preparing a cooked meal. I had gastroscopy done and I don’t have Celiac disease nor allergy to gluten, but I don’t eat gluten or wheat because I have heartburn afterwards.


  10. When increasing your fiber consumption, you have to also remember to increase your water intake, or else constipation will definitely be an issue. This is especially the case if fiber is increased heavily in a short amount of time. Good luck!

  11. I am curious why I could add to my smoothie that will help me with not being constipated. I am really enjoying the green smoothie but have completely lost my urge to go to the bathroom at all. Thanks for any help!

  12. I am searching the web for reasons I have gained at least 5-7 pounds since starting green smoothies. I started drinking two green smoothies a day about two MONTHS ago. Neither have much fruit in them. One has unsweetened almond milk (morning) and the other water. The bulk of both smoothies is kale, spinach, tomato (one small), carrots, cucumber, brussel sprouts, etc. I do add wheatgrass powder, and sometimes chia and flax seed. I eat a mid-morning mean of raw cashews and a banana (not a ton of cashews either), my lunch is light and often vegetable based. I do not keep sweets in my home so snacks are egg whites, etc. I workout twice a day most days now for 20-30 minutes. However, while I am eating the most nutritious diet of my LIFETIME and working out more than ever (I always worked out, but not like this) I feel bloated, some of my work clothes feel tight and the scale shows a 5-7 pound gain. Now, I have not gained more in the last 3 weeks but no matter what I do I can’t get the scale to head in reverse. I’m not heavy by any means, but I should see my body firming up and NOT gaining weight. Also, I am not speaking muscle. My belly feel bigger and I feel heavier so while maybe a pound of two is new muscle, something is not right.

    1. This is a late reply I know but I might have an answer for you. Are you obese or really overweight? At first your body will be resistant to losing, when you cut back you mau notice the scale increase a few pounds. It’s your body trying to hold on to fat, it can be stubborn,even up to 3 months but you keep up and it will kick in. Trust me. Once you reach your ideal weight, losing a few pounds will be easier.

    2. I didn’t read your whole post…sorry. cardio, at least hour a day, hard will up the fat melting. My opinion is if your trying to lose watch out eating nuts, alot of high calorie seeds. That’s just how I lost weight. Whenever I put nuts ..peanut butter or any…I gained! Best of luck!

  13. This may sound silly but when drinking green smoothie for weight loss, is it replacing a meal or on top of the meals? I drink about 1.5 litres of green smoothie (sipping throughout the day) with no added sugar and little fruits and homemade kombucha, I am putting on weight so quickly!

  14. My son has been doing a 90 day challenge working out and taking more of his protein shakes. He is eating healthier but not the green smoothies or vegetable protein. I believe he is still detoxing because his tonsils enlarged and he ended up in the emergency room. They gave him steroids and antibiotics. They wanted to admit him also. Now they say he needs his tonsils out. I would love to help him not have surgery and learn about how to get healthy and detox so this will not happen. Any suggestions? He is concerned that since this incident happened in the last 3 weeks and still is not completely over that they will again enlarge.

  15. Medically speaking, constipation usually is defined as fewer than three bowel movements per week. Severe constipation is defined as less than one bowel movement per week. There is no medical reason to have a bowel movement every day.

    I used to have constipation issues, but i started taking a supplement that keeps me regular. I have a bowel movement EVERY DAY since I started taking the Lady Soma Fiber Cleanse. I take them for about 2-3 weeks out of the month. I do not always need it every day, but it has totally regulated my system.

  16. Hi, anybody relate with green smoothies causing acne? I almost always get a bump on my chin after a green smoothies, particularly spinach and half green apple, celery. Could these be affecting hormones…anyone know?

  17. You aren’t “backed up”, you lack the necessary intestinal flora to digest the food properly. Take lots of probiotics, drink lots of water and back off on the greens for awhile. Have some raw seurkraut and Kombucha every day, you’ll get there.

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