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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:

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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Join the conversation

  1. Readers should be aware that most pharmacies will give you a meter for free. We’re constantly inundated with coupons to process free glucometers for folks, and happy to give them to anyone interested.

  2. I had to remake that graph because I couldn’t get it to copy. The ones from the paper look far worse.


    You can imagine the results of telling a patient to come back in 6 months to a year and you’ll check it again.

    This is the reason I like what you’ve just put out. My blog is a “sick” blog related to a specific, if common, type of diabetes. My audience is limited. Yours is a “health” blog. As you can see from the graph, FBS and A1c won’t protect you from this problem. The meter, however, will work for almost everyone.

  3. Wow, that’s quite a steep curve! I know Jenny Ruhl has written a lot about the myth that the onset of T2DM is gradual. As often as not, it’s quite sudden as your graph indicates. This does support the idea that repeated post-meal spikes are problematic regardless of what the average (A1c) is. Of course this is supported by the literature, as well.

    • “This does support the idea that repeated post-meal spikes are problematic regardless of what the average (A1c) is. Of course this is supported by the literature, as well.”

      Could you expand on this or link to references?

  4. Given the action of counter regulatory hormones, genetics, environment, and the heterogeneous nature of diabetes, that graph is to be expected. The graph is for two days and tells us nothing about progression or diet. It is said that these people were not diabetic but that is taken from the A1c and we have already talked about problems there.

    Every single one of the people in that graph could, in fact, be a future diabetic. We have no way of knowing since diabetes is inferred from a group of tests. I suffer from abrupt type 2 diabetes onset. This is the graph I wish to show.


    What you see shows no real progression. It stays steady and then takes off. A person with this could pass all manner of tests and still be in the hospital within a year. My little experiment points me to cumulative trauma as the problem here, persistent glycemic excursions breaking down the normal insulin mechanism.

    We really have no idea what “normal” is but we do know what levels cause damage. There might be some who escape damage much like people who only smoke a little a day but the great majority are going to be harmed. The numbers are clearly there and going over them, in general, leads to damage and going over them consistently will lead to cumulative damage.

  5. Hi Chris. Yes, I agree.

    Another strange pattern that I think was discussed on Stephan’s blog was a marked increase in blood glucose several hours after a high-protein meal. This I suspect is also related to a delayed and abnormal glucagon secretion.

    Btw, I think you’ve seen this graph from Christiansen’s research group, which suggests that blood glucose varies chaotically, even in the normoglycemic:


    Tom Naughton suggested that the folks with the highest peaks of BG would probably develop diabetes later on (the participants were young at the time the measures were taken). I have my doubts, because the highest peaks were not consistently found in the same individuals after meals.

    • Hi Ned,

      I’ve seen that graph (and entire presentation) and I read your blog post about it too. The question that remains is how “normal” those subjects really were. We know that metabolism can be damaged very early on in life – even in utero. It’s entirely possible in my mind that the people having the greatest blood sugar fluctuations throughout the day were not normal, but metabolically damaged. Perhaps these are the folks that go on to develop diabetes. Perhaps they already had some degree of reactive hypoglycemia, swinging from 170 mg/dL to 50 mg/dL. A1c is just an average. If someone is bouncing around from 170 mg/dL to 50 mg/dL, they may have a normal A1c because that would be an average of very high and very low readings. But that doesn’t mean they have normal BG. There’s also a lot of research, which I mentioned in a recent article, suggesting that post-prandial BG is a much more sensitive marker for predicting future problems than A1c.

      It’s also possible, of course, that spikes up to 170 mg/dL and down to 50 mg/dL are normal and part of a chaotic daily fluctuation even in healthy people. I still wonder why that happens in some healthy people, and not in others. It certainly indicates some difference in glucose tolerance and utilization. Whether that difference is significant or not would be the more important question.

  6. This article and the comments section is so educational. I thought I knew lots about this issue, but it has been great to learn more about what RH is, and about strange PP numbers.

  7. Interesting. But these patients are not only gluten free, but completely grain free (paleo).

  8. “I’ve seen another strange pattern a few times where the patient’s blood sugar actually decreases after the meal at the 1- and 2-hour mark, ”

    FWIW, Before my spouse went gluten free, he had a similar pattern.

  9. Karen: thanks! It’s nice to be appreciated.

    Ned: I agree. That’s something I see fairly regularly in practice. Generally appears as a below baseline reading at the 3-hour mark after significantly elevated readings 1- and 2-hours after the meal.

    I’ve seen another strange pattern a few times where the patient’s blood sugar actually decreases after the meal at the 1- and 2-hour mark, and then increases at the 3-hour mark. i.e. it might be 105 before the meal, then 95 one hour later, and 90 two hours later, and then 110 again three hours later. That one definitely has me scratching my head, but I suspect cortisol/glucagon dysregulation.

    • Hi Chris, a friend sent me this article and both of us are trying it. I did mine before dinner, not lunch, so maybe that’s the problem. Before, it was 70mg, after an hour it dropped to 61, 2 hour it went up to 85, then stayed at 85 at the 3 hour mark. This morning, true FBG was 108. I’m so confused. I am eating VLC, about 20g a day for about 2 months. A professional blood test about 2 weeks ago put me at 88 FBG. Not sure if I need to be worried.

      Thanks for the site, I love it!

    • My numbers are all over the place. I have hypothyroidism and in four months I’ve had my medicine adjusted from Synthroid 112mcg to 100mcg to 88mcg. My A1C has gone from 5.8 to 5.3 in four months. During months 1 and 2 , as my meds were being adjusted, my fasting blood sugar readings were 81 and 83 in the doctor’s office. I purchased a glucose monitor a month and a half ago and began closely monitoring my sugar levels. Though I have recorded a few fasting blood readings in the low 80’s earlier on, my fasting readings are routinely in the high 90’s. Oddly, upon eating a low, moderate carb meal or a non restrictive carb meal, my readings are near always within the optimal/normal ranges. For example, I had a 12 oz cup of Mango Lassi, 3/4 of a piece of naan, a serving of curried chicken and about 3/4 cup of white rice. In one hour after my last bite, my reading was 91 ( about 90 minutes from the start of this meal). Another example: I ate a serving of homemade lasagna and had a diet coke. In 1 hour and 35 minutes my reading was 83.
      What is happening here? How can I lower my fasting sugar levels? Most all of my 1 hour -2hour after meal readings are below my fasting. Help!!!

  10. One thing to consider adding to these suggestions is a simple test of reactive hypoglycemia. This would be useful, because reactive hypoglycemia so often precedes a pre-diabetic condition.

    I don’t have the references now, but if I recall correctly, RH usually occurs 2-4 h after a high-carb. meal, and the key piece of evidence is a BG reading that is significantly lower than the baseline.

  11. I’m totally with you Chris, regarding Walmart. I took it upon myself, with the suggestion of a diagnosed diabetic friend, to get the ReliOn Ultima at Walmart. I don’t patronize that store, but made the exception because in his experience, this meter had the least error because each pack of lancets comes with a calibrator for that particular pack.

    Testing my glucose has been eye opening, in that I’ve discovered on my own, that balance in food really works. The feedback loop of having a meter has made all the difference in my life. I can have whatever I want, so long as I control portions, and eat carb fat combos. I didn’t understand why this was working until I read this post. You’re brilliant, helpful, wonderful, and I’m thankful for your work and genuine caring about health. I read you religiously.

  12. I just made a trip to Wally World and bought the ReLion Ultima for $9. No strips, but 10 lancets come with it. Strips were $20 for 50, or $39 for 100. The WalMart site says that ReLion is a brand made specifically for them, so that is why it can’t be found elswhere, unless it is under a different brand name from the same manufacturer.

    I have a strong family history of diabetes and at age 45 finally checked my sugar while visiting a relative recently. My fasting was around 102, and a 2 hr post pancake binge was around 125 or so. It surprised me because my weight is fine and I do exercise. I also love sugar, and now finally have a “hit home” reason to deny myself all of those frequent guilty pleasures. Clearly now is the time to buckle down on the diet a bit. I will now be able to follow my progress directly with the new monitor.

    Thanks for the outstanding service you provide. The education is priceless!

    • The ReliOn Prime has strips for about half the amount than the Ultima. So just wanted to point that out for future purchasers.

  13. The Walmart meter and strips are also the only ones I’ve found that allow storage at temperatures under 59 degrees. We keep a cool house and nighttime temperatures dip into the 40’s upstairs. Most strips won’t tolerate that.

    That said, I do notice a difference with a cold meter and strips (even though within the Reli-on guidelines) and a meter and strips pre-warmed to 80 degrees or thereabouts. Any idea why that happens?


  14. Wonderful post! This is where the rubber hits the road – you and your meter can create the right diet for you. The comment about food intolerances is spot on too!

  15. I loved this!
    The one point that I keep reiterating on my site is that people should eat to their meter and that is what they should base their dietary guidelines on.

    I began taking this tack after talking with various diabetics on diet. Invariably, they were given advice on what to eat by their diabetes educators and docs. What I had to say was meaningless to them because of the prevailing wisdom being put out there by people who should know. There is a loop hole, however, and it relates to food allergies. No food, no matter how “healthy” it’s supposed to be, should be eaten if the person has a bad reaction to it. This loophole allowed to me to put this diet information in a form that is allowed by both FDA and ADA so I could get around the credentials issue.

    Testing for food intolerances using a glucometer is something anyone can understand. Healthy becomes what does not push that meter over 140. All the rest of the diet seems to fall in place after that.

    The other way to couch it is through vanity. Tell people that they can use this meter to lose weight and suddenly they will pay the 60 bucks so they can look better on the beach next summer.

    Jenny is a wonderful resource. No matter what arcane piece of research I’m digging in, her site or blog always seems to pop up.

    My most recent post, having to do with self-experimentation, points up the fact that prediabetes is diabetes. My loss of 1st phase insulin response, due to glucose desensitization, in the “prediabetic” range shows there’s nothing “pre” about it.

    Again, good job!

    • Michael,

      Food intolerances (other than carb intolerance) raise blood sugar above 140? How does that work?

    • Thanks for the clarification, and for the direct links. I’ve been wanting to be able to do that for a long time.

  16. What would a compromised phase II insulin response be? How could one fix that? Re: cortisol, would it be high or low cortisol causing issues?

    When you say back to baseline, does that mean the exact figure? Like if the pre meal figure was 85, would the 3 hr PP of 89 be okay?

  17. Kim: thanks for the tip!

    Lynn: in general it’s suggestive of poor glucose tolerance, but specifically may point to a compromised phase II insulin response or cortisol dysregulation.

  18. Great post! I have done the fasting and one and two hour PP’s, but I never did the 3 hour one. Interesting…

    I will get some new strips and go for it.

    BTW, what does it mean if the 3 hr PP is not back to baseline?


  19. Hi Chris! Just wanted to tell you a little research will net a FREE glucometer. I got mine last week and it included a free membership to get the test strips@ a discount. It’s a Freestyle Life and uses the smallest blood sample on the market. The offer is probably still available.