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How to Prevent Diabetes and Heart Disease for $16

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In the last article in this series on diabesity and metabolic syndrome, we discovered that the blood sugar targets established by the American Diabetes Association are far too high, and do not protect people from developing heart disease, diabetes or other complications. And we looked at what the scientific literature indicates are safer targets for fasting blood sugar, hemoglobin A1c and either OGTT or post-meal blood sugar.

On the other hand, we also discussed the importance of context: why it’s important not to rely on a single blood sugar marker, and how healthy people can sometimes have blood sugar spikes above 140 mg/dL one hour after a meal. Please keep this in mind as you read through the rest of this article.

In this article I’m going to introduce a simple technique that, when used properly, is one of the most effective ways to maintain healthy blood sugar and prevent cardiovascular and metabolic disease – without unnecessary drugs.

I love this technique because it’s:

  • Cheap. You can buy the equipment you need for $16 online.
  • Convenient. You can perform the tests in the comfort of your home, in your car, or wherever else you might be.
  • Personalized. Instead of following some formula for how much carbohydrate you can safely eat, this method will tell you exactly what your carbohydrate tolerance is, and which carbs are “safe” and “unsafe” for you.
  • Safe. Unlike the oral glucose tolerance test (OGTT), which can produce dangerous and horribly uncomfortable spikes in blood sugar, this strategy simply involves testing your blood sugar after your normal meals.
The strategy I’m referring to is using a glucometer to test your post-meal blood sugars. It’s simple, accessible and completely bypasses the medical establishment and pharmaceutical companies by putting the power of knowledge in your hands.

It’s one of the most powerful diagnostic tools available, and I use it with nearly all of my patients. Here’s how to do it.

Step One: Buy a Glucometer and Test Strips

A glucometer is a device that measures blood sugar. You’ve probably seen them before—they’re commonly used by diabetics. You prick your finger with a sterilized lancet, and then you apply the drop of blood to a “test strip” that has been inserted into the glucometer, and it measures your blood sugar.

There are literally hundreds of glucometers out there, and their accuracy, quality and price varies considerably. The one I recommend to my patients is called the Relion Prime, which can be found at Walmart.com. (Note: as a rule I don’t like to support Walmart, but I haven’t been able to find this unit anywhere else at a similar price.) Even better, the test strips, which you’ll need on an ongoing basis to monitor your blood sugar, are relatively cheap for the Relion Prime. You can get 50 of them for $9.00 at Walmart.com ($0.18/strip).

If you’d like the option to sync your readings to an iPhone or iPod Touch, the Relion Prime syncs with the Glooko MeterSync Cable. The Glooko cable (with the free app on your iPhone/iPod Touch) allows you to sync all readings, as well as track factors that affect your glucose level, such as carbohydrate intake, activity level, and how you’re feeling. Though the cable costs $39.95 on Amazon, it’s a worthwhile investment if you plan on tracking your glucose levels over a long period of time.

I’m sure there are many other choices that work well, but this is the unit I have the most experience with, and in general it is very reliable. Another good choice is the TrueTrack meter drugstores sell under their own brand name (i.e. Walgreens, Sav-on, etc.). Other models to consider are the One Touch Ultra or one of the Accu-Chek meters. The problem with these, however, is that the test strips tend to be more expensive than the Relion Prime.

Step Two: Test Your Blood Sugar

  1. Test your blood sugar first thing in the morning after fasting for at least 12 hours. Drink a little bit of water just after rising, but don’t eat anything or exercise before the test. This is your fasting blood sugar level.
  2. Test your blood sugar again just before lunch.
  3. Eat your typical lunch. Do not eat anything for the next three hours.Test your blood sugar one hour after lunch.
  4. Test your blood sugar two hours after lunch.
  5. Test your blood sugar three hours after lunch.

Record the results, along with what you ate for lunch. Do this for two days. This will tell you how the foods you normally eat affect your blood sugar levels.

On the third day, you’re going to do it a little differently. On step 3, instead of eating your typical lunch, you’re going to eat 60 to 70 grams of fast acting carbohydrate. A large (8 oz) boiled potato or a cup of cooked white rice will do. For the purposes of this test only, avoid eating any fat with your rice or potato because it will slow down the absorption of glucose.

Then follow steps 4 through 6 as described above, and record your results.

Step Three: Interpret Your Results

If you recall from the last article, healthy targets for blood sugar according to the scientific literature are as follows:

MarkerIdeal*
Fasting blood glucose (mg/dL)<86
OGGT / post-meal (mg/dL after 1 hour)<140
OGGT / post-meal (mg/dL after 2 hours)<120
OGGT / post-meal (mg/dL after 3 hours)Back to baseline
Hemoglobin A1c (%)<5.3

*To convert these numbers to mmol/L, use this online calculator.

Hemoglobin A1c doesn’t apply here because you can’t test it using a glucometer. We’re concerned with the fasting blood sugar reading, and more importantly, the one- and two-hour post-meal readings.

The goal is to make sure your blood sugar doesn’t consistently rise higher than 140 mg/dL an hour after a meal, but does consistently drop below 120 mg/dL two hours after a meal, and returns to baseline (i.e. what it was before you ate) by three hours after a meal.

There are a few caveats to this kind of testing. First, even reliable glucometers have about a 10 percent margin of error. You need to take that into account when you interpret your results. A reading of 100 mg/dL could be anything between 90 mg/dL and 110 mg/dL if you had it tested in a lab. This is okay, because what we’re doing here is trying to identify patterns—not nit-pick over specific readings.

Second, if you normally eat low-carb (less than 75g/d), your post-meal readings on the third day following the simple carbohydrate (rice or potato) challenge will be abnormally high. I explained why this occurs in the last article, but in short when you are adapted to burning fat your tolerance for carbohydrates declines. That’s why your doctor would tell you to eat at least 150g/d of carbs for three days before an OGTT if you were having that test done in a lab.
If you’ve been eating low-carb for at least a couple of months before doing the carbohydrate challenge on day three of the test, you can subtract 10 mg/dL from your one- and two-hour readings. This will give you a rough estimate of what your results would be like had you eaten more carbohydrates in the days and weeks leading up to the test.
It’s not precise, but it is probably accurate enough for this kind of testing.

Third, as I said above, an occasional spike above these targets in the context of other normal blood sugar markers is usually no cause for concern.

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Step Four: Take Action (If Necessary)

So what if your numbers are higher than the guidelines above? Well, that means you have impaired glucose tolerance. The higher your numbers are, the further along you are on that spectrum. If you are going above 180 mg/dL after one hour, I’d recommend getting some help—especially if you’re already on a carb-restricted diet. It’s possible to bring numbers that high down with dietary changes alone, but other possible causes of such high blood sugar (beta cell destruction, autoimmunity, etc.) should be ruled out.

If your numbers are only moderately elevated, it’s time to make some dietary changes. In particular, eating fewer carbs and more fat. Most people get enough protein and don’t need to adjust that.

And the beauty of the glucometer testing is that you don’t need to rely on someone else’s idea of how much (or what type of) carbohydrate you can eat. The glucometer will tell you. If you eat a bowl of strawberries and it spikes your blood sugar to 160 mg/dL an hour later, sorry to say, no strawberries for you. (Though you should try eating them with full-fat cream before you give up!) Likewise, if you’ve been told you can’t eat sweet potatoes because they have too much carbohydrate, but you eat one with butter and your blood sugar stays below 140 mg/dL after an hour, they’re probably safe for you. Of course, if you’re trying to lose weight, you may need to avoid them anyways.

You can continue to periodically test your blood sugar this way to see how you’re progressing. You’ll probably notice that many other factors—like stress, lack of sleep and certain medications—affect your blood sugar. In any case, the glucometer is one of your most powerful tools for preventing degenerative disease and promoting optimal function.

Nutrient deficiency is another critical factor to consider if you’re struggling with high blood sugar. Studies have shown that inadequate intake of vitamin D, magnesium, biotin, chromium, thiamine, choline, vitamin C, and EPA/DHA may contribute to both diabetes and obesity and that correcting these deficiencies helps to maintain normal blood sugar.

A nutrient-dense, whole-foods diet should always be the foundation of how we consume nutrients. Sadly, due to declining soil quality, a growing toxic burden, and other factors in the modern world, we can no longer rely on food alone to meet all of our nutrient needs. This is where smart supplementation can play a role. I formulated Adapt Naturals to add back in what the modern world has squeezed out and provide you with all of the nutrients you need to feel and perform you best.

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306 Comments

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  1. Hello, I’ve read a lot of your information regarding Diabetes, and learned a lot. I had a question for you Chris,
    I eat a lot of fast-food like burgers, fries,(I’m a 28 yr old male, lightwieght,) but lately i checked my Blood Sugar with Accu-check Aviva a couple of times, the results after eating wheat bread and now are:
    1 hour later: 103mg/dl
    3hours later: 100mg/dl
    I have been feeling somewhat thirsty more than usual and using the restroom more often, would i be able to reverse this? I’m not sure if i should go see a doctor? I hope its not T1.
    –>Anyway, thanks for all the information you gathered, It’s amazing work you have done and I read most of these comments, really helpful 🙂

    • Nice article, and thanks for posting the link. It presents an equally impressive argument, though i would have been more convinced if there were more scientific studies for reference point. The truth could be multi faceted, where many parties could be on the right track, and reach the peak truth, which is effective health.

  2. I’m a bit confused about the effect of carbohydrates on a low carb diet. Do they increase insulin resistance or improve insulin sensivity?
    My experience is that in the beginning, few days after the adaptation period, eating carbs (sweet potato, a piece of fruit, rice) wouldn’t spike my blood sugar… It always remained on the 100-110 range. I decided to stick with it for a couple more weeks to see what happens but now I have blood sugar spikes to 130-150 (just from eating an apple(!), or eating the occasional sweet potato). What does this means and why does this happen? should I be worried?
    thank you for your time and sorry for my english, I’m from Spain.

  3. Hey Chris,

    When doing the OGTT at home, you mentioned using an 8 ounce boiled potato. But when I look it up online, it appears that a potato does not have 75 grams of carbs. Also, do I eat the skin, or just the flesh?

    The reason I am wondering is that I have seen creeping FBG over the last few years: 84, 92, then 84, and in January 95, and am wondering about the OGTT. I failed the one hour test when pregnant, but passed the 3 hour OGTT (over four years ago).

    In February this year I did the 3 year OGTT, but they administered 100 grams of glucola, rather than 75 grams. Keep in mind that I am a 90 pound, 36 year old woman. Here were my readings with the 100 grams: fasting 95, 30 min 174, 1 hours 221, 2 hours 191, 3 hours 132.

    Now I am scheduled to have a repeat OGTT on Monday where they will give me the 75 grams.

    I have reduced my carbs to fewer than 50 per meal and seem to have normal readings, never getting above 120 or 130. I ate 50 grams last night, and it went like this: 89 at 1 hour, 134 at 2 hours, and 111 at 3 hours. Fat and protein were part of the meal.

    I also tried 38 grams of carbs of buckwheat hot cereal a few days ago, with coconut oil, rice protein powder, macadamia nuts, and flaxseed meal in it, and I spiked to 166 at 1 hour, but dropped to 99 at 2 hours.

    I am an active, thin, healthy woman, but concerned about the possibility of being pre-diabetic. What are your thoughts? Also, my cholesterol/triglycerides numbers are fantastic, blood pressure 90/58, and have no family history of diabetes.

    Thanks so very, very much,
    Allison

  4. So basically if the carb challenge is outside the ideal range we must consume less carbs and are considered carb sensitive? My fc has been 75 and on average the 1 hour post meal 105, 2 hour 88, and 3 hour 76. Once I did the carb challenge, my levels were 175, 140, and 115. But I have been eating semi low cabr/primal for the laste 4 months or so and last month has been pretty high in fat. Also, for the carb chllenge I ate a bowel of rice as opposed to a cup!

  5. Thank you for the great information. I was convinced my blood sugar would show spikes, as I have found the ONLY way I can lose weight is to almost completely cut carbs. Creating a decent calorie deficit, but still including “healthy carbs” yields NO results for me. My results were consistently numbers below your “ideal” scale. Do you have any thoughts as to how carbs could be so detrimental to my ability to lose weight, when they do not seem to abnormally affect my blood sugar levels?

    • I’m the same way Kristin.

      My theory is this: Carbs cause insulin to spike, but we’re not testing insulin levels, we’re testing blood glucose.

      If I eat a lot of carbs, I won’t have enough insulin, so blood sugar goes high.

      If I eat medium to low carb, I have enough insulin, so blood sugar stays in normal range, but the insulin causes excess glucose to store as fat. So even if I’m low carb and at a calorie deficit, I fail to lose weight because of high insulin levels.

      If I eat very low carb (just vegetables), insulin stays low, blood sugar stays low and I’m able to lose weight.

  6. Chris,

    what can someone who is having higher than ideal FBG readings do? Mine are now 99 when tested at the hospital and over 100 when tested at home.

    i eat paleo, i eat low card, exercise – don’t eat SAD. If diet and lifestyle changes aren’t helping – what are next steps?

    I suspect that my high FBG is due to some meds i’m on: HC and cytomel. I dont think I’ll ever be able to get off the cytomel, but am starting to wean of HC (i’m only on a low dose 15 mg or less a day…hoping weaning wont be too painful).

    is metformin worth bringing up to my dr? Even if my FBG isnt due to lifestyle if my BG levels continue to be high, I have to assume its having adverse affects in my body.

    I have normal to low testosterone and hear metformin can affect that too.

  7. Dear Chris,

    Thank you for the very informative web site. I had misconception of every overweight people will have Diabeties and slim ones will not.
    I am trying to find an answer to my conditions, your input will be really helpful.

    In september of last year (2012) my a1c came as 5.9 (fasting glucose number was ok)
    and the doctor told me I am pre-diabetic, suggested to control my carb and sugar intake.
    I am 5 3 and 129 pound at the time

    In 3 months (usual time interval to go back for another lab work) ; I have increased my workout intensity (4 times a week, 30min each weight training)
    lost 11 pounds (118 pounds now),
    totally cut down white bread, rice, potato, dessert, juice, soda, any bakery related products (crackers, cookies etc) from my diest
    start watching the G Index and G load food that I am eating.

    In december my a1c number came exactly the same 5.9! I was in shock, and I am getting mixed messages from doctors from the same office, one says 5.9 prediabetic the other says it is not.

    I have the family history, so I know I should take care of that number (it is at the high end), but I am not sure what the next step would be…

    Thank you very much for your time
    Nurcan

  8. Hi Criss for the past week I been monitoring my blood sugar with a glucometer. My fasting blood sugar is always the highest of the day from 96-111 postprandial is 1 hour=106 2hours=88 before i go to bed 80-95, random glucose is never more than 100. If I fast 8 hours after breakfast my sugar is around 80-90. How come if I fast overnight my numbers are higher than fasting after a meal. I work at a hospital I work at night I dont know if the schedule has something to do with this number my doctor told me my Fasting blood sugar is not that high that I should lose weight and excercise but did give me an answer as why my sugar is high in the AM and good all day long

  9. Hi Chris,
    I did your the baked potato test after following my blood sugar levels for a couple of days. My question is this, at the three hour mark, what if you bs reading is less than what you started out with? For example, my fasting was 90, I ate the potato, at the 1 hour mark it was 137, at the 2 hour mark it was 112 and at the 3 hour mark it was 75(less than my fasting at 90). I have not been diagnosed as a diabetic or a pre-diabetic but I am trying to be proactive because both of my parents have type 2.
    Thanks for your wonderful site

  10. … interesting article.. but the whole science of leptin is missed and even if onces BS is ok after 1, 2 or 3 hours… that ignores the fact that insulin would have spiked and the sugar would have gone somewhere, t might be fine when you are younger but keep spiking your insulin and soon you will become insulin resistant and then when you follow this simple test.. then you will see your bs numbers unable to keep as low as they did when you were not insulin resistant. Would it not be better to just not spike your insulin in the first place and thus not become insulin resistant… and enable you to stay healthy for longer..

  11. Chris,

    I have been experimenting with this over the course of the week and it has been fascinating. I’ve found that my blood sugar is actually highest upon waking in the morning (First thing) usually after a 9-10 hour fast. If I wait roughly 2 more hours it seems to drop a bit.

    What was really interesting is that it stays very low 1, 2, and 3 hours after meals. roughly averaging 95-97. Then around the 4 hour mark dips quit a bit.

    I follow a modified paleo approach based on your Paleo Code (love it!) These results tell me their might be some cortisol issues due to the elevated blood sugar in the morning. I’d love to hear your thoughts if you have any. Or any other body hacks I might be able to play with over the course of the day. I geek out on this stuff

  12. I had a Fasting Glucose Tolerance Test some years ago and the test came back ok. But…..the thing is the test was just for two hours.

    Fast for 12 hours [by the time they tested me it was 15 because they forgot me]……they took a sample….I drank the drink…..they took samples at half an hour, one hour and two hour [I think] and sent me off home.

    On the way home my blood glucose crashed [I have only felt that way once before after working and only having chocolates for lunch….I know I know….] and I rang the lab and told them what happened……..go to your doctor…….doctor said pre-diabetic so eat like a diabetic……so I got Mum’s books and read up on it…….thank goodness for the internet…….because if I had followed the books I would be diabetic like my Mother and Sister.

    In my readings I found a section that stated that you have to be tested at 2.25 hours and/or at the point of time you have any negative reactions….demand it if you have too.

    I have always been curious about what that reading would have been so when I feel a bit like that now I test and the blood glucose reading is always too low but I have never felt that bad again…..and I am not keen to.

  13. Can SSRIs raise blood glucose levels? I read and heard that they deplete chromium levels, which in turn cause BS spikes.

  14. I started eating and now am quite fond of plain Kefir from Whole Foods(low fat variety: 12gm Carb per cup), after reading Dr Kresser’s writing on Kefir as a therapeutic food item. I take it with a tablespoon of Rice Syrup. After reading this article on monitoring Blood Glucose using a Meter, I measured mine for this item, as part of Lunch(along with other Paleo-esque Lunch items, no other significant Carb sources; total Carb = 5(Veg)+12+18=35gms):

    Pre-Lunch : 92 mg/dl
    1 HR Post Lunch : 92 mg/dl

    So this may be a good find for LC me(may be others as well), for a food choice that does not send my blood glucose sky high(Btw, the fruity versions of Kefir at Whole Foods, with added Sugars, do the opposite, where the 1Hr Post Lunch Blood Sugar goes 125+). I am not diabetic or pre-diabetic but may be beginning to have some Carb tolerance issues. The Glucometer is a big help.

    My 2C.

  15. Hi Kris,
    I’ve been on low carb/ketogenic diet for the last 3 months now. I monitored my glucose after meals and it was ok – Fasting 93 – 98, post meals averages: 101 – 108 in 1hour. Recently I wanted to check my glucose during exercise and I was surprised to see the result of 140 after 23min of High Intensity exercise (right before exercising was 89!). Do you think it is normal? Do you know what might be the cause of this? I’ve checked my A1C level recently and it was very high-6,4%. Do you think it might be caused by HIT alone?

  16. Chris, can you comment on low testosterone and insulin sensitivity?

    I was examined by a clinician recently and he was confident that I have hypogonadism (I’m having blood lab work done today to confirm). I was out searching for some causes and effects and I ran into the following article:

    http://care.diabetesjournals.org/content/28/7/1636.full

    Also, I did my first glucose monitor tests yesterday and I had values all over the place (88 after waking, breakfast – 117, 137, 83 (1 hour, 2 hour, and 3 hour), lunch – 104, 121, 100, and dinner – 190, 100, 112. Obviously having the macadamia nut cookie from Subway didn’t help!

    I had a 101 fasting glucose level measured a few years ago and had a follow up HbA1c measurement of 5.1 so I had been basically assuming things were fine.

    I have about 18% body fat so my weight is pretty good but I have ulcerative colitis and apparently it is a secondary cause for hypogonadism. I couldn’t find anything on Jenny Ruhl’s site about low testosterone.

    • Yes, one of the primary causes of low T in men (which I discussed in my radio show episode on andropause) is insulin resistance leading to excess aromatization of testosterone into estrogen. This can be confirmed by testing your estrogen levels. Optimizing insulin and leptin sensitivity and reducing aromatization is the key to reversing this pattern.

  17. Hi Bev,

    Thanks for your reply. I just visited the ReliOn website – and while there noticed that a home test for A1c is also available at an affordable price. Something else for my growing “arsenal”. What a great service for people without insurance, etc. I have good insurance so I’ve not given a lot of thought to getting lab work done when whatever is happening with my body started. But, after learning more about various tests – and experiencing what I have recently with doctors – I’m leaning more toward getting my own testing done.

    I’m coming to my own conclusions about what’s best for my health. I feel a bit like that saying about a person who acts as his/her own attorney has a fool for a client. I would have never gone so far out on this limb as I am now if it weren’t for experiencing two approaches from doctors. They either give lip service to the value of lifestyle changes and then pull out a prescription pad – or they just watch the slide further into poor health, like disease is inevitable. My current (newest) doctor actually sees me as “basically healthy” – for my age, I assume. In some ways I really am healthy for my age – for any adult age – but the areas that need work aren’t getting the right stuff – until now that is.

    Geez.

    Whatever happened to medical doctors who actually appreciate patients who are responsible for their own wellness? Have they all died or gone into doing talk shows?

  18. Thank you so much for your reply. Good to know that the pattern is familiar, even if my measures are extreme.

    I have a hunch about what might be happening. I’m a 59 yo post-menopausal female (no HRT) with recent diagnosis of mild hypothyroidism (not autoimmune) – and what looks (to me) to be metabolic syndrome: Elevated triglycerides, decreasing HDL, and central obesity. I am NOT morbidly obese, however.

    I’ve discussed that possibility with more than one MD but no one wants to give me that diagnosis. The reason given has always been that my blood pressure is excellent, 115/75 (as is my resting heart rate). And, of course the emphasis has always been on TC and LDL-C. The advice has always focused on low fat dieting. Right. You know the drill.

    Well, I tried the low fat route and fairly easily got the LDL returned to normal and the triglycerides also lowered – but not to normal. Great. So, that’s when I decided to give the low carb approach a try – and was immediately captivated by how little I miss the carbs and how much better I feel overall. I’m a solid convert.

    But, I am only a recent convert. Haven’t had any lab work since going low carb. I still have the tummy fat to melt off, the lipids to lower, and its winter so I am not exercising as much /regularly as I do the rest of the year. My bad, I know, but there it is at the moment. Anyway, I wonder if the issue is that I am “melting” adipose fat – depleting lipid stores – right now and that’s causing the extreme measures. Maybe the pattern will remain – but shift into a normal range as I lose the weight, lower the lipids, and increase exercise. As in the way we see even diabetic glucose and lipids improve with weight loss and exercise. While low carb diet may confer immediate benefits, wouldn’t the most benefit be derived over time with total fitness?

    Does my thinking on this subject seem reasonable to you?