Category: Grain Brain


Blood Sugar and Your Brain

Several years ago, when I wrote Grain Brain, I had a long discussion with our publisher centered around choosing the best subtitle. Ultimately, we decided to emphasize the toxic role of sugar and carbs on the brain, and with good reason. Since that time, there have been a large number of studies that have confirmed the thesis that elevated blood sugar is profoundly detrimental, not just for the brain in general, but for brain function as well.

As the authors of a new paper entitled, Brain atrophy in ageing: Estimating effects of blood glucose levels vs. other type 2 diabetes effects point out, our brains shrink as we age with as much as 5% volume loss occurring between age 60 and 70. And as you would expect, this correlates with declining function.

A lot of the research has shown that type 2 diabetes (T2D) is what accelerates brain aging. But as this new study shows, it’s not the diagnosis of T2D that is the issue. Well before that diagnosis is made, brain structure is affected by blood sugar, even in the “normal” range!

As the authors state:

In conclusion, this study showed that the impact of blood glucose on the brain is not exclusive to T2D, and that blood glucose levels even in the normal range can have a significant impact on total brain and grey matter atrophy. These results emphasize the need to consider the role of higher normal blood glucose as a risk factor for brain health. 

So again, the mission here is to keep blood sugar low. Useful lab tests include the blood sugar with the goal of keeping it in the upper 80s to low 90s, the average blood sugar or “A1c” which ideally should be in the range of around 5.2, and the “fasting insulin level” with a target of 8 or lower.

These goals are best achieved by a diet that’s exquisitely low in sugar and welcomes healthful fat back to the table. Keep in mind that artificial sweeteners, paradoxically, are also know to elevate blood sugar, so no more aspartame!

  • JIll

    HELP!! i eat NO sugar, not even fruit and in a month my blood sugar level went from 102 to 114! i only eat veggies, olive oil, ghee butter and some meats, not even beef. No alchohol.I am at a loss. i have gone to SO many drs, have had Lyme disease for decades, cancer, heart attack . i have eaten healthy for years, organic, free range etc. I am close to giving up as no matter what i do i just keep getting worse

    • Lynn Dell

      I hope you can find a good functional medicine specialist. You can search here, and look by the names to see if they are IFM certified: https://www.ifm.org/find-a-practitioner/

      • JIll

        thank you. believe it or not i have seen several functional med drs… and on the list a few. lots of tests lots of $. 1 of them was even on the “top50 drs…of some list that Dr Perlmuter is on” I have gotten worse . I really dont even know what to do anymore..

        • Emmalee

          Jill…….please see my comments above. Do you have access to a health psychologist?

          • quiethinker

            So sorry Jill! It sounds like something is not quite right. There are good and bad functional docs also I’m sure. What part of the country are you in?

          • David Perlmutter
          • JIll

            thanks. they are on the list…. do you have any idea why it would go up when i cut out even fruit? 2 ( non drs) thought that it could be because my pancreas is working over time because i dont have ENOUGH sugar… I dont know. this same group told me i had CIRS 3 years ago and had brain damage. ( neuroquant MRI) but I went and had another MRI w Neuroquant and Neurologist says no… I am beyond confused.

          • Julie

            Have you tested B12 and ferritin? Low levels can cause brain fog. Maybe you’re not getting enough carbs for you. You could try upping them a bit and see if things improve. I don’t thing very low carb works for everyone.
            Sleep is the foundation of good health so try to get 8 hours. Also get regular exercise but also take time out for rest and relaxation, maybe try mindfulness to help counter stress. Good luck x

        • Kay Till

          Jill, have you heard of Envita Natural Health Center in Scottsdale, AZ? They have an in depth treatment protocol for Lyme Disease. Found it when I was researching Lyme treatment for a friend.

          • JIll

            Hi thanks yes i have heard of it tho not too terribly much . did your friend go? thanks!

    • Joe


      i do fasting glucose readings which are usually in the mid to upper 80’s. they spike to high 90s low 100s with poor sleep quality and or stress. The good thing about functional medicine is it identified underlying issues. The caution is once you find somehting that needs attention, avoid getting stresses or else you can count on poor sleep and then blood pressure, glucose etc rises.

      • JIll

        i dont sleep well at all. so i think it ha to be stress and lack of sleep. I am very frustrated tho as the drs just dont come up with anything to help. TONS of supplements, IV vitamin C( which has made me worse somehow) etc etc. thanks for your comments!

        • Joe Petrone

          you are welcome- if you have hot flashes related to menopause you may want to try relizen. My wife has had hot flashes for past 15 years. we started to be more intentional and found from her doctor this herbal supplement. she still gets hot flashes at night on occassion but not always which is improving her sleep quality dramatically.

          also supplements need to build on a foundation of good diet and exercise. my wife was under impression for a problem take a supplement. So she is starting to learn more about being personally accountable.

          • JIll

            Thanks, unlike your wife i have done the diet and exercise when i was capable. I am so sick now somedays i cant. I used to compete on the horse show circuit and have farms. I try and get on a horse every day but some days…I was a very fit person. Now my life is just shit… And i know most of it stems from Lyme but I cant believe there isnt anyone out there that can help.

        • eileenfb1948 .

          I heard that IV vitamin C is not good because it is synthetic and lacking in the whole spectrum such as rutin and flavonoids which causes an imbalance. Vitamin pills also are artificial – try to get vitamins from food or nutritional yeast.
          Dr Terry Wahls researched how to do that and had remarkable success.
          I wish you success on your journey to health.

          • JIll

            thanks. I just WISH i could find a dr that would look at everything and not just put me on a ton of supplements and run all these test that i have done over and over. I do everything they say and i KNOW i am a difficult case. BUT seriously if i could fix it myself i would! but no i spend thousands and thousands of $$ ( i am well over 300,000.00) and no better. probably worse.

    • Sharon Lee

      Jill You didn’t mention grains? I eat no bread, pasta, oatmeal, corn, or potatoes etc. They turn to sugar very fast and have the same overall effect as eating sugar and fruit. If you are doing a Keto way of eating, it just may take awhile longer to get the desired results. My numbers fluctuated greatly the first couple months. Also, the youtube videos by Jason Fung MD on how to cure diabetes are really great. Please don’t just give up, you are worth it. Hang in there you didn’t get to high blood sugars over night and they don’t go down immediately either. Best of luck.

      • JIll

        Havent eaten grains in YEARS! havent eaten even gluten free in months. Literally the only sugar i WAS eating was fruit and i have even stopped that. for 2 months +.I only eat organic meat eggs and veggies, and not even beets or high sugar veggies…

        • Sharon Lee

          I have the best results with intermittant fasting. Dr Fung is who I follow. His book” The obesity code” is good but “The complete guide to fasting” is fhe best one. I think the numbers difference is not all that significant from 102 to 114, it is the disease of diabetes you want to stop not just focus on numbers. Dr Fung helps people cure type 2 diabetes all the time. You might find this helpful The perfect treatment for Type 2 diabetes https://www.youtube.com/watch?v=1a2Fsfa8e4I&t=324s it is only 12 minutes

          • JIll


    • eileenfb1948 .

      High protein intake causes higher insulin.
      High cortisol – check it out as I think it can raise blood sugar.

      • JIll

        not tons of protien at all. protein bone broth powder in the am and then eggs, or piece of chicken, etc. just enough to survive…

    • Are you on a statin medication? Statins can raise your blood sugars by 60%! It happened to my husband. I’ve researched this issue extensively. Dr. Dwayne Graveline’s book’s Statins Thief of Memory and Statins Damage Crisis. Also Drs. Sinatra and Bowden’s book The Great Cholesterol Myth. Excellent starting points. Great research data.

      • JIll

        nope only took for about 2 months and told the dr I wouldnt take them due to the harm they caused. that was about 8 months ago. but certainly a valid point thanks!

    • a.savino

      Jill, diabetes runs in my family. ( 3 brothers 2 sisters & mom )One thing I believe strongly the amount of stress we allow in our minds and bodies can give us more than diabetes.!!!
      17 years ago I visited I well known Dr… my A1c borderline to become diabetic…. After he told me trough out all my supplements and do nothing because I will have full diabetes in less than a year..
      I told him he should give up his medical licence…. today 17 years latter my a1c and fasting blood sugar normal…
      Life Extension suplements learning how to live in the present moment be active eat healthy and don’t worry change my life:) hope this help ..Alicia

      • JIll

        thanks i do take a boat load of supplements, many form Life extensions.. the only thing left to blame IS stress as i dont eat anything with sugar! no diabetes i my family..

    • Onika

      Maybe you have Type I diabetes. Maybe you have a thyroid problem.

      • JIll

        hmm well i do have a bit low thyroid and am on Armour! Been on it for 4 months and in the last 3 weeks my glucose level went up which just makes no sense … thanks

    • Brian Mowll

      Jill, It sounds like yours is a more complex case. Your diet sounds good, so there must be something else driving up your blood sugar. You mentioned that you are taking Armour – I would make sure you’re getting thyroid levels checked (T4, T3, fT3, thyroid antibodies), and if they are not optimal, work with someone who can adjust your medication. You also mentioned Lyme. Chronic infections are a common source of elevated cortisol which will raise glucose levels in the blood. Physiological and emotional stress factors are a significant driver for blood sugar problems and diabetes. Lastly, make sure you’re supporting gut health, because there is a strong correlation between gut derived inflammation and insulin resistance, leading to blood sugar and brain problems.

      • JIll

        thanks.. I do have the thyroid checked, taking probiotics, enzymes AND seeing a functional gastro interologist 🙂 I do believe most of the prblems stem from Lyme but after going to at least 6 LLMD over the last 10 yrs still no better. I appreciate your comments tho! and i try everything i can think of… my cortisol at last check wasnt bad.

      • abby

        Also, a fascinating truth to the whole blood sugar regulation topic, is that paradoxically, Fat can block the receptors and you will end up with high blood sugar. You will see your blood sugar drop, very likely, if you reduce the amount of fat in your daily intake. It seems like totally wrong, but people are reducing their meds and eating fruit, just by restricting dietary fat. check out Anthony William website free blog on diabetes, one of his talks on Hay house radio he interviews a young type 1 diabetic who has started a business helping diabetics working with this protocol. unfortunately I cant remember his name but you can find it from Anthony William’s info on Hay House Radio. Good Luck!

        • Brian Mowll

          I’ve worked with thousands of people with diabetes and found that this is true in a certain percentage. There’s no doubt that elevate FFAs and visceral fat around the liver and pancreas will lead to insulin resistance and affect insulin production. It’s not about consumption of fat though, it’s more about what the body does with that fat. If the cells are properly metabolizing fat, then you can eat healthy fats without compromise. Fruit has a combination of sugars, between 20-65% fructose, depending on the fruit. A medium apple, for example, has 25 g of carbs, about 20 g of sugar. Fructose does not require insulin for metabolism and won’t raise glucose levels. It has been associated with elevating triglyceride levels though, increasing FFAs and insulin resistance. Even though more than half comes from fructose, an apple still has enough sugar to raise blood glucose levels in most people with diabetes. Some people with diabetes can tolerate fruit, others cannot.

        • JIll

          I am listening to the digestion summit and low and behold I thought your name sounded familiar 🙂 I so wish i could find someone to help me. The blood sugar issue is relatively new and maybe not that hi. 114? had the A1c test done yesterday so we shall see

          • JIll

            I guess i should have waited to post. 114 not so good. Im in Northern VA and then Gainesville Fl area after Nov. any suggestions? Also having lots of pain in stomach area nothing shows up on ultra sound. getting scan this week. Inflammation from endoscopy

    • abby

      Also, a fascinating truth to the whole blood sugar regulation topic, is that paradoxically, Fat can block the receptors and you will end up with high blood sugar. You will see your blood sugar drop, very likely, if you reduce the amount of fat in your daily intake. It seems like totally contradictory, but people are reducing their meds and eating fruit, just by restricting dietary fat. check out Anthony William website free blog on diabetes, one of his talks on Hay house radio he interviews a young type 1 diabetic who has started a business helping diabetics working with this protocol. unfortunately I cant remember his name but you can find it from Anthony William’s info on Hay House Radio. Good Luck!

    • Murray Pinkham

      Hi Jill, I am not a doctor or health expert but I am a Christian and I am praying for you.
      I have just had a triple bypass 11 weeks ago, so obviously I got some things wrong in the past. My pathway now is basically vegetarian and restricting animal protein(incl. meat, fish, eggs, dairy) to 5%. This is what the China study diet showed. Look up websites of Dr T Colin Campbell, Dr Esselstyn, Dr Mcdougall, Dr Dean Ornish for real life stories. Blessings, Murray

    • Lori

      Please reach out to Dr Gerbarg. She had a very challenging case of Lyme disease that nearly disabled her. She is fully functional again. http://www.breath-body-mind.com/patricia-gerbarg-md.php

    • Karen Conklin

      I just listen to nine days of parasite Summit Dr. Murray. If you’re harboring Lyme disease or have heavy metal toxicity parasites thrive on mercury. Do you have mercury fillings? The fibroid is the canary in the coal mine very susceptible to toxins

      • JIll

        Hi- i did have a parasite test a well as heavy metal 🙂 no parasites but some metals so working on that! thanks

    • sab1053

      Hi Jill

      Get another opinion from a Functional Medicine Doctor. Yes, it could be the thyroid. Stay away from chlorinated and flouridated water for drinking and bathing. Both can wreak havoc on the thyroid. You could have a chronic low level pancreatic infection, chromium deficiency etc. The function Medicine Doctor will order the right tests.

  • Lynn Dell

    Before blood sugar rises, insulin rises. When insulin resistance ensues, there is way too much circulating insulin except in crucial areas of the brain, for some reason, where levels are too low, and they are low as a consequence of insulin resistance. These crucial areas of the brain cannot then use glucose for fuel, and there is brain shrinkage. Insulin is as important as blood sugar in this matter.

  • Emmalee

    I do have to comment a bit more. I appreciate that less sugar is important. However, exercise helps as well. It would have been good to know if family history of Type 2 diabetes was a correlating factor. Stress, anxiety, pain, obesity…..all raise blood sugar levels…….I am pre-diabetic and can personally testify. I check my sugar levels twice a day…more if I am having pain, stress etc. A1C being checked routinely. My primary MD very open to new ideas, treatments.

    I am also a RN. I have had in the past, an opportunity to be a patient followed by a health psychologist. Again…very holistic approach and open to new ideas.

  • GC

    Have you tried ginger shots? That’s pure ginger juice from a juice machine. There are many simple dietary changes you can make that will help! I’m type 1.5, and don’t take insulin or any other medications- I manage my sugar exclusively with diet and activity.

    • JIll

      no but do grate ginger into my protien shake..

  • cshekoski

    What about stevia? Is that safe to have?

    • anon

      it is a natural product, if it doesn’t have additives, it should be safe.

    • Allison

      Use pure, Liquid stevia only. The powdered forms contain additives.

  • Ronna Berezin

    Jill … Go see Peter Osborne regardless of how long it takes to get an appt. He answers questions like yours daily and his book No Grain, No Pain is worth. reading. His research will fill the gap in yours.

    • JIll

      i will look into thanks

  • Clubstav

    Apart from the known effect of sugar consumption and insulin/blood sugar etc please specify regarding protein. I had read that there was some research that protein can also raise insulin levels. What would be the ideal amount of protein -since in a keto diet would be difficult to avoid?

  • Dahne Rodriguez

    Everyone seems to only mention t2d, but what about t1? I would think that there would be more of a brain decline risk. I gave been keto, no grain, for 2 years now and certainly see far less brain fog and my bg’s are mostly in the normal range.

  • Dale

    I have seen some studies that Berberine 500 mg twice a day acts like Metformin. I was able to get my bl sugar down on my own but can’t loose weight without the Metformin, so I will try to go on the Berberine to see if it will indeed act like the Metformin I had been on and was able to loose weight on.

  • Hnina Gourmet

    There are so many creative ways to eat gourmet decadent food without having to suffer from this poisonous substance. There are no other choices but to cut it out of our diet. More and more people are aware of it. Still there is so much more education work to do.

  • David

    Thanks for the info. My question – is it in every case that diabetes can result to brain aging? Correct me if am wrong but I know most decline or aging of the brain are age-related. And older people with diabetes could be expose to brain aging than younger ones. What do you think?

    Source: https://healthiack.com/health/what-is-normal-blood-sugar-level

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