Doctor's Note

Note the boost in calcium absorption described in the video can only compensate if you’re taking enough in. For example, dietary acid load may be associated with lower bone mineral density in those getting under 800mg a day.

I previously touched on this topic in my video Is Protein Bad to the Bone? But I promised I’d take a deeper dive, and here it is! If there are other topics you’d like me to cover in greater depth please note them below in the comment section.

Plant Protein is Preferable to animal protein for a variety of reasons (tends to have less methionine, is less IGF-1 promoting, etc.), but it’s not clear how much of an advantage it has when it comes to bone health.

Note to chemistry geeks: of course it’s the calcium salt anions that really do the buffering (carbonate in Tums and phosphate in bones), but I’m trying my best to simplify for a largely lay audience! Get ready for some kitchen chemistry (actually bathroom chemistry!) in my next video Testing Your Diet with Pee & Purple Cabbage.

For more context, check out my associated blog post: Does Animal Protein Cause Osteoporosis?

If you haven't yet, you can subscribe to my videos for free by clicking here.

To post comments or questions into our discussion board, first log into Disqus with your account or with one of the accepted social media logins. Click on Login to choose a login method. Click here for help.

  • elsie blanche

    So am I understanding this correctly… “excess protein consumption boosted calcium absorption, from down around 19% up to 26%.”?

    It seems to me that this lends itself to the possibility that a more acid-forming diet
    is better for calcium absorption. Is my (our) plant based diet too alkaline? Vegan bodies becoming less able to absorb the calcium than our fellow carnivores? I’m a bit thrown off by all this thinking. Anyone?

    • Veganrunner

      Absorption (intestine) but that doesn’t mean it is being used by the bones. In the studies it is turning up in the urine.

    • Maha

      Agree with you Elsie….true, this is confusing.
      That leaves me thinking, should we also infer that calcium from animal sources is not used by the body in the sense, it simply passes through the digestive tract and gets excreted! Whatever calcium we derive from the diet is ONLY from plant sources?! We need more research..
      – Vegetarian since birth

    • Alex

      I believe that’s precisely what the video is not saying. Acid/alkaline has no or little influence on the absorption of calcium in the digestive system but protein seems to increase calcium absorption.

      Why is there more calcium excreted in the urine? I didn’t quite catch that. Maybe because there tended to be more calcium to begin with from animal sources?

  • Merio

    i wait the test…

  • The science is a bit confusing and these studies do challenge the scientific paradigm of acid base. As we see the science keeps coming however it is important to remember that our bodies consist of many systems working together. Bone health is about alot more then calcium… Amy Lanou’s book, Building Bone Vitality, lists 18 other substances needed for bone health. From a general health standpoint a varied non GMO whole plant based diet with adequate Vitamin B12 seems to be best supported by the science. For patients with osteoporosis the “best” diet is now being rethought. It seems that there is general agreement that weight bearing exercise is beneficial for everyone. The problems with animal protein in the diet as far as other diseases such as kidney disease and cancer are still there. These studies demonstrate the need to keep up with the science but also point to the limitations of reductionistic studies when dealing with complex systems.

  • Martha

    My mind leaps ahead – then why do countries whose people eat more meat and consume more dairy have proportionally higher rates of osteoporosis? One theory I have heard is that these people are more sedentary. There’s always another question!

    • Terri

      There’s also a vitamin D link with bone health, and most of the high dairy consuming countries are further north of the equator. (or perhaps the casein protein in dairy damages the bones as well??)

    • beccadoggie10

      When I ate meat and dairy I was NOT sedentary. But, for the most part, other than walking my dog 2.5 miles per day, I was not doing weight bearing exercise. Instead, I was swimming 1.5 miles per day plus walking.

      Since fracturing my spine, going vegan to reduce pain and inflammation, I’m doing Pilates, which is more weight bearing to build stronger bones, and am trying to walk, which is very painful.

  • Adrien

    Wow, Exactly the kind of exciting video I was waiting for ! Since “Is Protein Bad to the Bones” we were in lack of explanation. Can’t wait for the next video !! I used to believe in this theory and I find it really sane to challenge my own dogma, that’s the only way to move forward. Congratulation Doc.

  • beccadoggie10

    I still find it more painful to consume dairy or meat including fish than eating a plant based diet and getting my calcium from collards, and to a lesser extend kale, and bok choy than yogurt, which I loved but did not help me prevent osteoporosis.

    It is actually painful for me to eat dairy or flesh of animals and it is not just in my mind. My injured (but now healing) spine and legs where I have had a total hip and knee replacement scream in pain. Perhaps, the pain is caused by all the poisons that have built up in animal protein (and fat) from excessive use of pesticides that are falling from the sky as rain, in surface and groundwaters. Livestock and wildlife do not drink carbon or RO filtered water. They drink whatever comes from the tap or the waterways. So, even if the livestock are raised by the organic method, they are still consuming pesticides and industrial poisons.

    It’s healthier to eat very slow on the food chain –plants!

  • DrBarbaraHoldeman

    You mention that the calcium in and the calcium out are pretty much a wash… so in my thinking you are not getting calcium to build bone mass if you are getting rid of what you consume. Eating a plant based diet may not give you the calcium absorption but you also would not be excreting what your eating. Why do the countries that consume the highest amount of dairy have the highest amount of osteoporosis? Maybe it is because they are excreting the calcium they consume and so there is not enough for bone building?

    • Scott

      Is exercise the missing factor here? The body will only absorb what it needs and excrete the rest. If the bones is not being “built” through weight bearing exercise, it would be logical to assume that the body excretes any excess, regardless of where it comes from (plant or animal origin). I am very much in favor of a vegan diet and I do believe it is more efficient to provide calcium to the body, but if the body is not being challenged through exercise, it has no need of excess calcium.

    • Dr. Jack Sibrizzi

      My sentiments exactly Dr. Holdeman!! If there is a wash then what is happening long term to the density of our bones? I am seeing an alarming number of patients in my office over the age of 40 with T scores at least in the osteogenic range with lower extremity stress fractures.

      • Dr. Jack Sibrizzi

        I meant osteopenic range

  • Plantstrongdoc M.D.

    The only interesting thing is hard end point. Calcium here and calcium there – as Dr Forrester points out, bone health is about alot more than calcium. We are too reductionistic when we think of bone health and calcium. The question is, who is getting more hipfractures, meat eaters or people on a WFPB-diet. Well off to my calcium-pill………

  • Dr.Bill

    HEY, I’m a meat eater along with good source of vegetables (cruciferous mostly) ,I have a bone density of a forty year old .I’m sixty-five. So what gives!!
    Dr .Bill Natusch

    • John

      Perhaps an exception to the rule, or you don’t eat that much meat. ;)

      • mrcircumspect

        DrBill is on target. The five-dollar term he might have used ,’bio-chemical individuaity’ predicts and allows for bio-chemical variants … like yourself.

    • Plantstrongdoc M.D.

      And arteries of a ninety year old….

    • LouisaD

      Perhaps you do strength-training?

    • Terri

      Bone density in and of itself is not an indication of health – obese people generally have very high bone density because of the excess weight they carry around.

      • beccadoggie10

        I thought that also. But, it is not true. Despite my initial weight gain prior to going vegan, I was carrying around a lot of weight and fractured my hip and later my spine, and was diagnosed with osteoporosis.


    I think one could est s pirce of meat with hot peppers. hot peppers lower stomach acid. i have them with every meal to prevent GERD which started after gall bladder surgery. gall bladder went bad (dr said) from a combo, low fat diet and long time vegetarianism. then i beceme anemic and had to eat beef liver and their were new guidelines from healthy fats……. perfect storm

    • Lynn Maas

      Interesting about hot peppers for GERD. Hope you have better health in the future.

    • guest

      Your gall bladder did not go bad from a low-fat vegitarian diet, LOL! Your making this stuff up to dog on veggie diets. Oh, so eating guts and liver healed ya huh? hahahahaha.. That’s a bunch of old Weston A Price malarkey. lol! Try a WFPB vegan diet if you really want to re gain your health.

  • alanroy

    According to the studies cited, the extra absorption accounted for 93%
    of the extra excretion, or “nearly” the same amount. That still leaves a
    7% loss. We wait to see where that is coming from. We also wonder
    what is the actual mechanism increasing absorption, and how we might accomplish that without meat protein.

  • abeleehane

    2 questions.
    1> What if someone has very low calcium intake from his diet but still consumes lots of meat products, thus requiring buffering of the acidity in the blood. Where then, would the calcium be coming from.
    2> Since some of the “marked” calcium would be absorbed and integrated in the bones, how can we know for sure which is excreted (short half-life ?)

  • Denis Spasyuk

    would be nice to know about the yield of ALA transformation to EPA and DHA in our body. Wiki says that it’s virtually non existent. Is this true? If it is true why do people take flax seed oil?

    • Toxins

      This study showed that the conversion rate in Vegans is 2x that of a fish-eater from ALA to DHA/EPA.

      “Comparison of the PLLC n23 PUFAs:DALA ratio between dietary-habit groups showed that it was 209% higher in vegan men and 184% higher in vegan women than in fish-eaters, was 14% higher in vegetarian men and 6% higher in vegetarian women than in fish-eaters, and was 17% and 18% higher in male and female meat-eaters, respectively, than in fish-eaters This suggests that the statistically estimated conversion may be higher in non-fish-eaters than in fish-eaters.”

      • Denis Spasyuk

        interesting, thank you!

  • Denis Spasyuk

    another topic to cover is racemization of amino acids by microwave irradiation. Also, how method of cooking influencing isomerization of cis fats?

    • Lenard

      Excellent suggestions, Denis. I second your motion!

  • CoeyCoey

    The idea that consuming calcium will strengthen your bones is about as silly as thinking protein consumption will build muscle mass. In both cases, physical strain is needed to promote growth/strength.

    There are many articles about some studies that show vegans have lower bone density. They are all extremely misleading. If you read the studies, you will find that they do not compensate for the weight of the participants. And since vegans, on average, weigh less than non-vegans, their bone density is going to be less because they don’t have to support that extra weight. When the data is adjusted to include weight, there is no significant difference in bone density between any of the groups.

  • Javier

    This was way to confusing. The thing I understood was dietary calcium with meat was absorbed better into the body but no evidence showing it actually going to the bones. It mean it could have been laid down on the arteries for all we know. So then there is the acid problem which calcium then is leaching from the muscle to neutralize this. So two different situaitons going on. Protein helps absorption from diet but then the acidity of that protien causes mucles to leach calcium therefore weakening the muscle.

    So if dietary calcium is absorbed but then the excess gets filtered out do we know that any calcium is reaching those bones? A lot of unanswered questions about the whole process.

    And yes to much focus on calcium, innactivity and lack of sun are factors as well and probably thousands of other reasons we have not accounted for. Even gladiators had good bone density and markes that showed that they were vegetarian alkaline eating people. So the take away to me here is more greens, enough sun and physical activity keeps good bones. More junk and high acid forming foods, low D and low to no exercise is a recipe for bone fractures.

  • David Camerpong

    If the body sees ‘radioactive’ calcium being dumped into the system wouldn’t the body dispoae of the ‘radioactive’ calcium… straight away?? I know i would!
    I have osteoarthritis in the hips… I have never been a great consumer of dairy, hated milk as a kid still do, loathe cheese, but have a fondness for new zealand butter but in no great quantities sometimes on bread or a baked potato. And i would walk everywhere.

    But my diet choice was the atkins diet! 1lb of sausage for breakfast, piece of chicken for lunch…. So i reckon i am going to stick with the calcium down the toilet theory1

    • Alan

      I would concur – calcium is extracted from the bones to neutralise acid.

      People’s lives are saved by applying the theory that acid causes calcium from the bones to be extracted to neutralise the acid.
      Explanation: Hydrofluoric Acid is lethal in the smallest of topical applications to any extremity of the body; the HF acid draws (over the period of a number of days) calcium from the bones to the extent where the body is no longer able to regulate the electrical signals to the heart (as this is mediated through the skeletal bone structure) resulting in the patient dying from multiple ever increasing heart attacks. So how do they protect against this in industry? Besides having complete PPE (covering everything including hair, etc.) there are fully funded hospital wards for the application of calcium cream should the need ever arise (much like the addition of calcium to neutralise an acidic stomach).
      The system of death resulting of exposure to HF acid is stronger proof than any radioactive studies that the body does extract calcium from the bones to neutralise acid.
      They’ve also forgotten the obvious – what happens if there is no calcium in the diet – where do the researchers imagine it would come from then?

  • harvey

    Perhaps John Bergman’s You tube video Healthy bones,Healthy Life :
    Osteoporosis Cause and Solution will help . 45 minute lecture with some great points.

  • Ravi K

    Very interesting video. I am all for learning, unlearning and relearning :). So eating an animal protein diet increases blood calcium levels to a point that it is excreted in the urine. Why is this calcium not getting into the bone matrix to supplement the daily calcium loss (due to natural causes of course)? Would it be beneficial for these folks to take high doses of Vit D3 to help this calcium get into the bone matrix or some other transport agent (for eg R-ELF)? Would this slow down the excretion process and actually utilize the calcium better?

    • beccadoggie10

      I am now taking 2,000 IU vitamin D3 per day, as recommended by several physicians. Before I fractured my hip in 2006, I was swimming laps outside in the sun or walking my dog, again, outside. Wouldn’t I get enough vitamin D from the sun if I was exercising outside 45 minutes to 2 hours per day year around.

      We are living in South Louisiana.

      We all need calcium for other bodily functions, not just our bones, but I was trying to minimize bone loss without taking dangerous severe symptom drugs.

      BTW, I took cal-mag and other nutrients as part of my multi-mineral supplement with vitamin D for decades. But the level of vitamin D in the supplement was low then…about 400 mg. Now, online physicians and most nutrition researchers recommend 2,000 IU. I’ve found that if I take 2,000 IU or more, I urinate constantly. But, when I took 1,000 IU of vitamin D, my bones were not repairing themselves. Now, I try to ingest all my vitamin D for the day by noon.

    • beccadoggie10

      When I consumed dairy, as well as supplements containing calcium, it did not prevent me from getting osteoporosis. I was getting enough vitamin D from the sun, as I was swimming outside mid-day.

      However, I was not getting enough weight-bearing exercise and that may have had a big impact on the weakening of my bones.

  • rick

    Do we know if higher dairy consumption leads to weaker bones? If we do know this do we have theories as to why?

    • beccadoggie10

      What I know is that I consumed one quart of milk and 1 quart of low fat yogurt per day, which helped my bad cholesterol rise, and did nothing positive for my bones after I passed menopause. I did this for my entire life.

      I now have osteoporosis, and have had a total hip and total knee replacement and 3 spinal fractures.

      Since going healthy vegan (two years), I’m breaking less bones, doing Pilates 3x week, and walking very slow and a very short distance 3 days a week. I’m getting stronger.

      I think eating healthy vegan is better because my calcium and other nutrients are coming from dark, leafy greens and calcium rich beans instead of dairy and I no longer eat any kind of meat. I think plants are more easily absorbed by the body. But, I’m no expert.

      • CoeyCoey

        Hi Becca,

        I travel quite a bit for work, and when on the road, I will seek out more ethnic vegan cuisine than the Americana vegan junk food. Vietnamese, Korean, Thai, Chinese, Ethiopian, etc, tend to be mostly whole foods. Sometimes I just get a salad from Whole Foods salad bar, but that is usually pretty expensive. There are still some restaurants that offer salad bars. Souper!Salad! is all you can eat, and they have a pretty good selection on their salad bar.

        Your Pilates and other exercises will do more for your bones than increasing nutrient intake.

        • beccadoggie10

          Thank you for your feedback.

          My main concern was getting enough calcium, as I am getting enough magnesium, manganese and other nutrients needed for strong bones, but calcium seem to be always lacking. With significant osteoporosis in my spine, I’m trying to ingest 1000mg of calcium from food per day. This is no problem at home, but a major problem when I have no control over what I eat.

          • Toxins

            Ingesting calcium is not the only factor for having strong bones.

            Calcium needs for humans are not as high as the DRI may recommend, and if we consumed a low sodium diet low in animal protein, our calcium needs can be as low as 450 mg per day as discussed more extensively in this article from the Food and Agriculture Organization of the UN. As represented in the figure below, and citing from the article “In a western-style diet, absorbed calcium matches urinary and skin calcium at an intake of 840 mg as in Figure 14. Reducing animal protein intakes by 40 g reduces the intercept [calcium balance] value and requirement to 600 mg. Reducing both sodium and protein reduces the intercept value to 450 mg.”


            “Under the extreme condition of immobilization, rapid bone loss occurs despite consumption of 1,000 mg (25 mmol)/day of calcium”

            So exercise is important. Cooked greens like collards and kale can provide a lot of well absorbed calcium.

      • Jen Drost, Physician Assi

        Hi Becca, great comment :) I know this probably seems obvious, but, if you can, call the restaurant you plan to visit ahead of time, and ask them about healthy plant-based options. I have been surprised several times in the last year when I was handed a “Veg Menu” at chains such as Cheesecake Factory and Roy’s. Good luck :))

      • Tom Porter

        I’d like to interview you – please send contact info to

    • Toxins

      We do have the data to suggest this, but it was attributed to the acid/alkalinity theory. I do not know at this point.

      • rick

        At least based on this video I would suggest that the theory still stands other than the calcium is used to boost alkalinity before it ever gets to the bones. Final result being the same – more animal protein equals weaker bones.

  • Susan Zinaich

    I have been meaning to contact you about my pet peeve: Alkalarianism.
    As a Respiratory Therapist we study acid/base balance extensively. We analyze blood gasses from persons coming in for a simple PFT to the most critical of patients. The results that we see are predictable and reproducible, the hallmark of very good science.

    Dr. Greger, you and I, both know that it is VERY HARD to shift your pH out of the range of 7.35-7.45. Our respiratory system responds quickly to acidic metabolic changes, and our kidneys respond more slowly to respiratory acidosis in order to bring us as close to the normostatsis of 7.40. You and I, both, know that it is only the MOST critically ill patients who have pHs outside of that normal range.

    Furthermore, Alkalarianism condemns vinegar, ph of 2.2, as an acidic evil, yet, promotes lemon juice, pH 2.0, to alkaline, angelic-status. AHEM, Alkalarians, lemon juice is MORE acidic than vinegar.
    So, then the Alkalarian responds, “But it PROCESSES in the body as acid or alkaline.”….and I’m thinking…WHAT!??

    Blood pH is the most accurate way to measure the body’s pH. Has anyone drank a quantity, say, a third of a cup, of said “poison”,vinegar, then had a blood gas measured?…and then drank the same quantity of lemon juice with a follow-up blood gas? I bet not.

    My conclusion: Alkalarianism is bad science and quackery!

    Susan Zinaich, BS, RRT
    20+ year ethical vegan.

    • Coacervate

      Thank you Susan, you had the courage to say what I did not. Where the heck is this coming from? What is an alkalarian?

      I’m a chemist. Calcium cannot be a not a buffer. Its a divalent ion. There are cations and anions… some, like quaternary amines and carboxylic acids or carbonate ions can accept or donate protons so they are buffers. Calcium ion does not do that.

      This is all too strange to me. but you know, its Dr G. So what gives?

      2.5 years vegan, ethics…not so much.

      • I agree with the posts always nice to have scientists and other health care professionals joining in to the discussion. In my experience people are just trying to negotiate a complex world by developing beliefs or paradigms… term coined in The Structure of Scientific Revolution by Thomas Kuhn and more recently popularized in The Tipping Point. Remers work in 1990’s which looked at the effect of specific foods on the pH of the urine is the best one I have seen that has contributed to the alkaline/acid issue. Looking at his list of acid/alkaline foods you realize that animal products are at the acidic end and plants at the alkaline end. When you read Dr. Campbell’s new book, Whole, you get a sense of the limitations of reductionistic science when looking at complex systems. For me at this point in time and given the science as a clinician it is clear weight bearing exercise and eating less dairy and animal products makes the most sense. I don’t know if that is do to acid/base issues or vascular issues (i.e. the effect of blockage of middle lumbar arteries on low back health for instance) or the other almost 20 factors associated with bone health. Given our anatomy and physiology we are designed as hind gut fermenting herbivores who are adapted to eating starches. If we eat according to our design we do better. It is not a guarantee but stacks the odds in our favor. If you put diesel fuel in a gas engine you have problems. Keep tuned in to as the science keeps coming.

        • Eastlynn

          What about the studies that show higher intake of animal protein, with adequate calcium present, increases bone density more than vegan diets? I am confused as to whether I should go back to eating meat for to maintain a higher bmd?

    • CoeyCoey


      Consider this. When a food is eaten that creates acids upon metabolization, the calcium, or more likely, phosphate in the blood immediately reacts with that acid and neutralizes both into salt and water. The body doesn’t see a change in blood acidity, but it does see a change in blood calcium or phosphate levels. So, calcium or phosphate is pulled from the bones to maintain the blood calcium level.

      When you exercise, your blood calcium and phosphate levels increase as your CO2 levels in your blood increase to maintain pH. If they didn’t, you would enter respiratory acidosis. If you were to hyperventilate, your blood calcium and phosphate levels would drop to maintain pH. If they didn’t, you would enter respiratory alkalosis.

      I wouldn’t call it quackery, I would simply call it misuderstood. Lack of evidence doesn’t mean something is false. There are plenty of people who have cured cancer and many other diseases by eating an alkaline diet. I know I have seen many health benefits.

      • nathan G

        “There are plenty of people who have cured cancer…”

        Who, and how do you know they had cancer, cured it through their actions, and in particular through a change in dietary pattern? There’s plenty of quackery which relies on the emotionally appealing promise of CURING CANCER but which can only provide the weakest of evidence in favor of that claim.

        • CoeyCoey

          Anecdotal evidence may not be proof, but it is evidence, and to ignore it is foolish. Most empirical studies are based on the reports of multiple people’s anecdotal experiences.

          There are numrerous studies that show the benefits of a plant-based diet concerning cancer risk and growth. Since most plant-based diets are alkaline, you can draw a parallel hypothesis between an alkaline diet and cancer risk and growth.

          There are many studies that suggest many health benefits are obtained from a alkaline diet. Why is it difficult to believe that it may help prevent, or even cure some peoples cancer?

          • Toxins

            I agree there is strong evidence to suggest that a plant based diet is the way to go for cancer treatment, prevention and reversal; but I would disagree on the point of anecdotal evidence. Anecdotal evidence is the lowest standard for evidence and is generally not accepted in the scientific community.

          • CoeyCoey

            Toxins, You will find that most empirical studies first started as reports of anecdotal evidence. If enough people claim that cranberry juice helps prevent UTI’s, then scientists conduct a study to determine if it is a real phenomena or imaginary.

            Of course, anecdotal evidence is the most powerful evidence by whom it is experienced.

    • Toxins

      Your body maintains the ph balance using many many complex buffers. Citrus fruits are acidic but metabolize to net alkalinity.

    • Elizabeth RN

      Susan I just read your note above and am so glad I did. I am an RN. I think a lot of good science gets lost for the sake of hearsay which in this case is dangerous. I was just about to ask for help to understand how this “lemon theory” is any different from Kombucha which becomes basically vinegar once it ferments. I have osteopenia and want more than anything to stay away from acidic foods, like Kombucha, and I think now I understand that all I need to do is continue a plant based diet, and get away from all the “theories” and hype about acid/base foods. I’m not eating animals and that is the most important issue here. Thanks again for your explaining about PH. I am in agreement.

      • Joseph Gonzales R.D.

        Thanks for reposting this question, Elizabeth RN. There are four videos that discuss acid/base balance that you may find helpful. There is so much good research on citrus fruits! I can’t speak directly to kombucha and how the stomach breaks it down. It may have some healing properties but there are concerns about its consumption I love what you added and feel it;s very true ” I think now I understand that all I need to do is continue a plant based diet, and get away from all the “theories” and hype about acid/base foods.” YES!


        • Elizabeth RN

          THANK YOU so much and for taking the time so quickly to get back to me. I never saw a video on Kombucha and I do not make mine with mushrooms, but it’s vinegar for sure when I drink it and it’s time to GIVE IT UP. If even a couple of T a day, I’m done.
          The person who taught me drinks 12 ozs. a day and am passing the video on to her.
          Have a wonderful life and thanks for being there for all of us.

          Elizabeth Berry RN

  • Tony and Judi Spadaro

    I was trying to play your videos and had no sound. tried several times on my Mac1 the video plays, but no sound. I then tried on my ipad and got some sound then went away. This is the first time I have had trouble. Any thoughts?

  • Don

    But aren’t there studies showing that country-by-country per capita osteoporosis rates correlate highly with per-capita protein consumption rates?

  • matt

    Interesting..makes sense. all that is needed now it work out what really promotes osteoporosis? Just like any disease or symptom there is more than one road that can lead to it.

  • Veganista

    I’ve been eating vegan for 2 1/2 years (whole plant diet) with lots of cooked kale and green veggies,(as I am hypothyroid) with 1/4 of diet in whole grains, but my urine ph in the morning is always very acidic. After eating, by lunch time I’ve gone up to 6.8-7.0, but don’t seem to sustain this. My question; why is my morning ph so acidic? Is this cause for concern? I’m post menopausal and have osteopenia and I am noticing significant bone loss in my mouth, not at the gum line but the bone above the gum line seems to be diminishing. I have good dental hygiene, but clench my teeth. Do I have a nutritional deficiency. My dentist and periodentist are not interested in this question as there is no bleeding or gingivitis. I went to a bone doc who said, ask your periodentist!

  • Clea Green

    It is certainly more complex than looking at just the calcium portion. However, minerals come from the soil, so they are abundant in plants…the only reason animal flesh has calcium and other limited amounts (vs. plant based) minerals is because they eat plants (used to anyway, now they are supplemented in their feed). Instead of going through an animal for these minerals or nutrients, it makes much more sense to go to the source.

  • Joe Mitchell

    Side bar here, I want to touch more on the alkaline diet and a video I saw about, “The New Biology” and Dr. Robert Young stating that fruits that are acidic are not healthy. Is there truth to this:

  • Kev

    Yes…which is not a good thing…We do not need a lot of protein in the diet. And there is not a single person on the face of the earth who has ever been calcium deficient on a healthy diet

  • Mindaugas Raulinaitis

    About being calcium deficient on a healthy diet and even having higher osteoporosis risk than standard american diet: More Osteoporosis Seen With Raw Foods Diet. March 28, 2005 — Raw-food vegetarian diets are associated with osteoporosis, a new study shows.

    The study appears in the March 28 Archives of Internal Medicine.

    The study compared the bone health of 18 vegetarians who ate only raw foods with a similar group that ate a standard American diet. All participants were about 54 years old.

    The vegetarians had been following this diet for 18 months to 10 years. Food diaries showed they ate various raw vegetables, fruits, nuts, seeds, sprouted grains, and cereals. They strictly avoided cooked, processed, or animal-based foods. That eliminated dairy products in their diet, a major source of calcium.

    The researchers measured bone mineral density and also took blood and urine samples to measure bone turnover.

    The raw-food vegetarians had low bone mineral densities, indicating osteoporosis.

  • Skeptic

    Meta studies show that hip fracture rates are proportional to the amount of per capita dairy consumed in a particular country. What’s causing the additional bone loss in countries that eat more dairy? Other studies have also calculated BMD and determined it is inversely proportional to acid food consumption. Are people who eat less animal products, and hence more fruit and veggies, being protected by micro-nutrients that stimulate osteoblasts?

  • Evie

    If you end up absorbing more calcium eating more meat-can’t that access calcium be used to neutralize the acid that is formed from the animal protein? .. and eventually you pee it out? Why is there a question still of how the acid is being neutralized? At the end of the video, Dr. MG claims that just because it is in the urine does not mean it is being used -but it also does not mean that it is not being used to neutralize.,,, correct?

  • William Dwyer

    See the following studies showing that the alkaline mineral potassium bicarbonate (KHCO3) attenuates bone loss. Potassium citrate, found in abundance in fruits and vegetables, converts to potassium bicarbonate in the body, and therefore does the same if fruits and vegetables are consumed in sufficient quantities vis-a-vis acid-forming foods, such as meat, legumes and grains.




    I’ve improved my own bone mineral density over a two-year period as demonstrated via dexascan by supplementing my diet with KHCO3 along with ensuring that my urinary pH is kept sufficiently alkaline.

  • mdouble

    The research done to provide the evidence you site is brilliant and exceptionally useful. As with all things, to resolve any issue you must deal with facts not conjecture. It just goes to prove the point that old beliefs are not correct simply because they are old. Those who have held to the idea of calcium loss is directly associated with bone loss will have to re-educate and re-evaluate. On the other hand, there are still outstanding issues with highly acidic diets as they relate to things like arthritis and cancer. For me being vegan is still the best option.

  • Katie

    Dr Greger, I have a question. Are amino acids destroyed in foods during the cooking process?

  • Jaqueline

    Hello Doctor!

    So this morning I was talking to another mom and she commented that cheddar cheese prevents cavities in growing children. I would love to prove her wrong. I also read an article saying that milk causes osteoporosis but cheese and yogurt don’t.

    Thanks for your time.

  • Paul Spring

    This is so confusing. Dr. Greger should either withdraw this or explain it more clearly. Just because someone pees dietary calcium doesn’t mean a small percentage isn’t from bone – does it? How much of a small percentage during years beyond menopause ultimately leads to osteoporosis? Does the fact that the National Cattlemen’s Beef Association funded some of this research need to at least be acknowledged by Dr. Greger? Shouldn’t Dr. Greger point to a sentence in the study lauding the increased IGF-1 due to meat consumption as a potential reason to eat meat for bone protection? What am I missing here?

  • Alex

    Well strike us down from our vegan high horses! Is this the new combining recommendation: Should we eat our collard greens with beans?

  • William Dwyer

    If this is true, then why does adding potassium bicarbonate to one’s diet stop bone loss and even help to restore it? because it does. See for example:

    Frassetto et al. Potassium bicarbonate reduces urinary nitrogen excretion in postmenopausal women. J Clin Endocrinol Metab 82:254-59 (1997).
    Frassetto et al. Long-term persistence of the urine calcium-lowering effect of potassium bicarbonate in postmenopausal women. J Clin Endocrinol Metab 90:831-4 (2005).
    Sebastian A, Harris ST, Ottaway JH, Todd KM, Morris RC Jr. Improved mineral balance and skeletal metabolism in postmenopausal women treated with potassium bicarbonate. N Engl J Med. 1994 Jun 23;330(25):1776-81

    See the following diagrams at the end of this post: The first diagram (the line graph) shows the effect on urine pH of adding various amounts of potassium bicarbonate to the diet. The more KHCO3, the higher the urine pH. The second diagram (the black bar graph) shows the results for net renal acid excretion, which is a determinant of calcium excretion. Before supplementation, the NEA is high, during supplementation it drops dramatically almost to zero. After supplementation, it again rises to the previously high level.

    Potassium citrate is also effective for preventing and restoring bone loss (although potassium chloride is not):
    M. Marangella, et al.: Effects of Potassium Citrate Supplementation on Bone Metabolism. Calcif Tissue Int (2004) 74:330–335 DOI: 10.1007/s00223-003-0091-8
    Moseley et al. 2013. Potassium citrate supplementation results in sustained improvement in calcium balance in older men and women. JBMR 28(3):497-504.
    See also: “Potassium Citrate Boosts Bone Density in the Elderly” —

    Despite their obvious benefits, these potassium supplements can interact with some medications, including ACE inhibitors, potassium-sparing diuretics, angiotensin receptor blockers and indomethacin, increasing your risk for hyperkalemia, or high potassium — so only take them under the the supervision of your doctor.

    • William Dwyer

      I’m trying without success to delete this post, which unfortunately included graphs and diagrams that were not intended to be part of it. But every time I try to edit my own post, the edited result is rejected. I’m baffled as to how correct this. Does anyone know?

      • Joseph Gonzales R.D.

        I am on it! Let you know asap.

      • Joseph Gonzales R.D.

        Hey William. Only moderators can delete comments, but you can edit yours in Disqus See if that link helps?

  • PaulaE

    Dear Dr. Greger,
    Here is a copy of a question that I posed for Dr. Campbell. I was wondering what you thought about the 10% of the calcium that was not radioactive. In other words, would the calcium(non radioactive portion) urine loss be the same if they fed vegans some radioactive calcium and then a vegan diet? The assumption is that they’d have less radioactive calcium but they would still have the same amount(not percent) of non radioactive calcium in their urine. I was wondering the effect of the protein on only the calcium in the body that was not ingested with the food. Does the protein increase, decrease or have no effect on this fraction? Thank you.


    Dr. Campbell indicated that animal protein causes an acidic
    state in the body which is buffered by calcium. The calcium comes from the
    bones which causes increased calcium loss from the bones and contributes to osteoporosis.

    I’d like to present to the TAs and to Dr. Campbell information
    gathered by Dr. Greger that shows a different mechanism for the calcium loss in
    those eating an animal based diet that was elucidated via a radioactive calcium
    I’d like to know if Dr. Campbell finds any flaws in this information. I’d also like to know if the 10% of the
    calcium that was lost in the urine that was not radioactive was the normal amount
    of calcium for a person on a WFPB diet. Or did the animal protein not only
    increased calcium absorption from the intestine but also increase calcium loss
    from the bone simultaneously. Thank you.

    • Joseph Gonzales R.D.

      Hi PaulaE. I am not sure the answer. I don’t think a study like that has been conducted so we can make assumptions, but we won’t know for sure. Have you read all the studies Dr. Greger references? I suggest starting there to understand the research better. Did Dr. Campbell respond?

  • 1992Matze

    What is about the bioavailability of the radioactive calcium? Is it the same like natural calcium, so it doesn’t matter?

  • Shaun Fernando

    This is good.
    People might be able to read more interesting articles on .

  • Frances Morey

    Does squeezing a lemon or lime in one’s glass of water contribute to acidity in the body? Some say that such citrus acidity once in the body becomes alkaline. Is there any logical explanation as to whether or not this is true?

  • thpalex
  • Gabi

    Calcium does not act as a buffer. In the case of TUMS the buffer is carbonate, in the case of the body it is the phosphate that buffers and the calcium goes with it to keep the charge balance.

  • Mary Ann T

    Does taking K2 with calcium in a plant based supplement such as Alive brand and spreading it out over 6 or 8 small doses work? I am concerned about the spike in large doses, but am also not sure how good the calcium in fortified foods are( do they use limestone or…???) I try to eat just whole foods and am post-menopausal , small frame and already have osteopenia.

  • dkimble

    I’ve just joined, so sorry to comment so late in the game.

    I’ve been vegan for over 30 years and had always assumed the “animal protein=bone loss” idea, so I found this video enlightening.

    I’ve just learned of another study (prompting me to come here) that actually goes farther and states that *lower* protein intake is associated with *higher* bone loss in the elderly, and even that lower animal protein intake is associated with increased bone loss.

    The abstract of the study is here:

    This seems counter to all I’ve read from sources recommending plant-based diets. I’d appreciate some input from someone more knowledgeable than I am about this.

  • Ella

    Dr Greger,
    I went to the ER today with severe chest pain. All tests were negative and all is well (i’ll spare you the details). The DR I saw asked me to read up on acid vs alkaline diets. He said if your diet is alkaline heavy and therefore less acidic, you’ll never get cancer. If you agree with that, I’d love to see a video that explains it in relatively simple terms.
    Thanks very much for all you do.

  • David Barber

    I’m not understanding this supposed “boost in Ca+2 absorption” which accompanied the acid surge. Can somebody please explain? That Ca+2 wasn’t in the blood before the acid-surge, it was in the soft tissues. If it was in the soft tissues and not in the blood, then, wouldn’t we say it had already been absorbed in the soft tissues. Then the acid-surge desorbed it from the soft tissues? I think you see where I’m confused about the acid “boosting absorption.” Thanks in advance for explanation.