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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. What type of diet is recommended for reversing diabetes type 2? Should I eat to the glucometer? I’m having a hard time finding a medicine that I can tolerate. I could stand to lose a lot of weight. I’ve lost 45 lbs. Thanks

  2. I tried to read through all the comments but I didn’t see the answer. On the 3rd day, it says eat 60-70 grams CHO, and no fat, but can I include chicken or vegetables?

    • Not sure what Chris’ answer would be, but I would guess you should just have the starch. He did say “instead of eating your typical lunch.” Protein and veggies can definitely slow down the absorption of glucose into your bloodstream, so I would personally just do the carb.

    • no. the point is you eat only the carbohydrates specified, and nothing else that would impact how your body processes carbs into glucose. additional protein (chicken) would slow that down. addition carbs and fiber (veg) would impact it as well.

  3. The one thing i haven’t seen mentioned here is if you have issues at the 3 hour mark. I had a fasting 3 hour glucose test done at the clinic back in 2014. I’ve been told i have pcos which can affect blood sugar. My results were as followed after drinking the sugar drink…
    1 hour: 152
    2 hour: 108
    3 hour: 35

    Why would it drop SO low? I felt fine- just hungry. They unfortunately forgot to do insulin during the test- that was just glucose. My a1c came back at 5.7 about a week ago. Ice also had 2 unexplained really early miscarriages. Amy input would be greatly appreciated.

    • Some people have more of a tendency to get hypoglycemia than others. Sugary stuff is more likely to cause it since the quick highs it causes are more likely to lead to lows. The bodies of people with hypoglycemia tend to overreact by producing too much insulin. Even if you didn’t feel really sick, it sounds like you need to be particularly careful to avoid sugar. The solution is frequent, small meals that help to keep your blood sugar from going too high or too low.


      (Please ignore the part about low fat. It is unfortunately still conventional dogma.)

    • what’s probably happening here is that your pancreas produces insulin to clearing the glucose from your blood, but it’s not enough because you’re insulin-resistant – so your BG goes up. but then in response, your pancreas ends up flooding your system with insulin, which eventually clears out the high levels of glucose and then some — and voila, you have low blood sugar. this is a common pattern among diabetics / prediabetics.

      btw, the other solution, other than frequent small meals, is to eat a diet very low in carbs and high in fat, ie. ketogenic. this way your blood glucose never goes high OR low, and you don’t have to constantly be eating throughout the day.

  4. I have 2 questions:
    1. My baseline after many days of testing at different times seems to be 85mg/dl. Does this mean that the spike in blood sugar I am looking for should be adjusted since I seem to be on the low end?

    2. Does your blood sugar levels rising after a workout sound normal, and if so should you wait for it to go down before eating? Most often it will be higher (say 120) and then I eat my breakfast immediately after and an hour later (maybe 2) it is back down to 85.

    • Because the difference between 85 and 86 is like splitting hairs, you may be missing the point. As written in the post, “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.” In other words your BG shouldn’t regularly go real high, and it should return to “normal” after a few hours every time you eat something. If you’ve been exercising and it’s elevated some when you eat doesn’t matter; after a few hours it should return to “normal.” So what if it doesn’t? Then you may be insulin resistant, prediabetic or worse, and you need to be looking at making life changes to prevent diabetes.

  5. I seem to have the opposite issue- low blood sugar after eating. My fast BSG is usually in the low 80’s. A typical breakfast, 2 eggs, a little meat, and maybe have a sweet potato. 1 hour later I feel terrible and my BSG is 65-68. 2 hours after breakfast my BSG is 75-80 but I still feel crummy. If I have 50 grams of carbs, swet potato or white potato, for breakfast, my BSG at 1 hour is low 100s, and mid 80s at 2 hours, and I feel fine. From what I’m reading these low blood sugar may be from a overly large insulin release and might indicate that I’m insulin resistant. But if the cure to insulin resistance is to lower my carb intake, how so I so that without feeling like crap? Any thoughts are greatly appreciated.

    • Protein helps to stabilize blood sugar. Maybe an increase in protein would do you good. Also make sure to eat enough healthy fat. Lean protein and carbs together without fat would cause me major reactive hypoglycemia.

      • Airia, read his question again –
        the meal higher in protein caused him more problems with hypoglycemia. ‘Eat more protein for breakfast’ is not the answer for everyone.

  6. Here is question for you folks, that know more about this blood sugar thing then me……..when I wake up in the morning after a 12 hour fast….my sugar is in the 107-108 range…..testing during the day between meals it drops to the 90’s….even high 80’s…a safe range……..why after sleeping all night is it over 100….doesn’t make sense…….

    • Are you eating a low carb diet? Physiological insulin resistance is a common occurrence among low carbers—Google it for info . I had this issue and when I increased my carbs, the problem was resolved.

      • Hi there.
        I have the same issue.
        I am not sure how insulin resistance is the problem as someone else mentioned because your issue is earlier on in the morning.
        My educated guess for myself is cortisol. Cortisol is high in the morning and causes the release of sugar into the bloodstream.. My blood sugar is correlated to my cortisol level aka stress level/feeling. Always lower in the evening.

    • Just as exercise can cause your body to use insulin more effectively (the reason why exercise is included in life-style modifications for diabetics), rest can cause you to use it less effectively. This is part of what is known as Dawn Phenomenon.

      • what can we do about this?……I’m trying the bitter melon tea method before sleeping and when waking up in the middle of night….but I haven’t seen any change yet

        • well, an update…been on a low carb/no sugar diet for over 3 months and all my numbers are now good!….lost weight…( I didn’t really think I needed that)…but it did the trick……it is the sugar….I m convinced……even the dawn effect has dropped into below pre-diabetic range,

          • Hi Brian, I’m having the same issue as you described. How long were you low carb/no sugar until you noticed the morning BSL come down? And did you cheat at all in those 3 months?

      • thanks for the info Charotte……..the low carb diet seems to be correcting this issue……will have to wait and see……

  7. I am a T2 diabetic and for the last few years have had pretty good glucose and A1C levels with the help of Metformin 2x/500 and Tanzeum (6.1). My doctor took me off of Tanzeum after my total hysterectomy since my levels were good. After the surgery I began menopause, and now my levels are unbelievable high-fasting average 160, two hours after meals (around 200) and A1C (7.3). I exercise every day, eat a low carb diet, and drink coffee in the morning and water the rest of the day. I am so upset that I cannot lower my numbers, any suggestions? My doctor is threatening to put me back on Tanzeum and I really don’t want that.

    • I had 6.0 a1c, and 125 FBG while 220 lbs and on a std US type diet but without the junkfood. Meat at least daily, usually 2 or 3 times. I went whole plant food diet for other reason: coronary calcium score of 579 *very serious problem*. In a year I lost 40 lbs and a1c went to 5.5, fbg went to 97. But…this was using 2 x 750 metformin at same time, so… Anyway, interestingly my protein level went from lower-normal to mid-normal range on the plant diet with no meat or dairy. Before the metformin, but while on the plant diet, my urine test strips stopped turning colors, too, meaning postprandial glucose did not trigger the test anymore, even without metformin. I’ve heard that the whole plant food carbs are less trouble and raise insulin sensitivity, too. I have not added much exercise, this was by diet. The theory is the fat inside the cells goes away so insulin works better on this diet. Good luck with your efforts. Bob

  8. My father is a heart and diabetic patient from last 6-7 years. He takes a proper diet as well as he walks about 45 minutes daily in the morning but his blood sugar level is not decreasing. What should I supposed to do now?

    • This is a complicated, controversial issue with no quick, easy answers. You didn’t mention what he is eating or what pills he is/isn’t taking. Food is probably the most important issue. Some people swear by various supplements.

      IMHO, I would start by cutting out juice/soda if he is still drinking that, and cutting down on fruit and starch, if he is willing. If you want to help him, you and he will have to do your homework. I would start with Robert Lustig, MD’s books and youtube videos and Gary Taube’s latest book: The Case Against Sugar.

    • What is a “proper diet.” Most of the public dont have a proper idea of what a proper diet is. I would not be eating any carbs, and no sugar alcohols or fruit. Eat meat and leafy greens and fats like butter, olive oil, avocado.

      • I am currently enrolled in a FREE course given by Medicare. It is all over the nation, my Endocrinologist has a poster & referred me. Medicare wants to lower the cost of taking care of diabetes by educating the public. (Their words). Proper eating habits are a big part of it. The book they use (verbatim) is “Living a Healthy Life with Chronic Conditions”, the information comes from Stanford University School of Medicine. I feel the info is quite informative & of course as the title implies is for many conditions. The chapters for diabetes (if this eases the reading) in the order of the course are 1,2.11,18,5,6,12,8,9. They mention page #s too, which may not be in those chapters. Good Luck!

    • There was a Newcastle University study where an 8-week 800 calorie diet (600 calories on meal replacement sachets + 200 calories of non-starchy vegetables) reversed type 2 diabetes on some patients.

  9. I dispute the assertion that a low-carb diet makes you less tolerant of dietary sugar. I’m Type 2 and have been eating low-carb (lower and lower with time, until now I eat fewer than 30 grams of carbs per day) for over a year. As my A1c has lowered (from 10.2 to 5.0), I have become much MORE tolerant of sugar. I can now eat a “protein” bar that has 5 grams of sugar (8 total grams of carbs) without my BG going over 110 in the following hours. A year ago, when my dietary carb intake was much higher, such a bar would spike me above 150. Through this low-carb diet, I have pretty much normalized my BG without any drugs or insulin.

    • that’s what I want to hear….I was just told I’m prediabetic, never had this before, I work out, I’m slim…good diet…well, that’s about all I can do is cut some carbs and hope it works!

      • That’s sort of a strange argument that person is making. If you’re eating practically no sugar, your ability to tolerate it really is much less of an issue.