May 28, 2011
Now scientists have discovered a mechanism that may explain why this is the case. The study is Glycation of LDL by Methylglyoxal Increases Arterial Atherogenicity: A Possible Contributor to Increased Risk of Cardiovascular Disease in Diabetes. Naila Rabbani et al. Diabetes. Published online before print May 26, 2011, doi: 10.2337/db11-0085
You can read a good explanation of what this study means in this report from Science Daily:
Science Daily: Super-Sticky 'Ultra-Bad' Cholesterol Revealed in People at High Risk of Heart Disease
In brief the finding is this: LDL becomes dangerous mostly when it becomes glycated--i.e. when sugar molecules become bonded to it. When that happens it is more likely to stick to the artery walls. The oft-demonstrated close correlation between A1c and heart attack suggests that this dangerous glycation of LDL occurs at the same rate as the glycosylation of red blood cells--which what the A1c test measures.
This goes a long way to explaining why there is such a poor correlation between measured LDL levels and the occurrence of heart attack. Though the makers of expensive statin drugs have brainwashed doctors into believing that high cholesterol translates into high risk of heart attack quality research has never borne this out--just as it hasn't borne out the idea that lowering cholesterol with statin drugs will prevent heart attacks in the general population.
If this newest research finding holds up, it may turn out that testing for glycosylated LDL will predict with good accuracy whose LDL levels put them at risk for clogged arteries.
If that turns out to be the case, it may finally get through to doctors that the best approach for preventing heart attacks will not be statins--which don't alter the glycation of LDL. Instead, the key to preventing heart attack will be to keep blood sugar from rising outside of the truly normal level after meals.
What is that truly normal level? Research has made it crystal clear. It is under 140 mg/dl (7.7) at one hour after eating. Additional heart=attack-specific research suggests that the likelihood of having a heart attack rises significantly when post meal blood sugars go over 155 mg/dl (8.6 mmol/L) at one hour after eating.
Not so surprisingly, if you keep blood sugars in the truly normal range you will also end up with an A1c that is in the range 5% and under range that other research has found correlates with a very low risk of heart disease.
Insight into Why Trials of Lowering A1c in the Elderly Don't Lower Heart Attacks
This new finding about glycated LDL also explains why studies of elderly patients who have lowered their A1c only after decades of exposure to very high blood sugars do not show that lowering A1c reduces heart attacks. The longer the time period during which your arteries are exposed to glycated LDL, the more of it is going to accumulate in your arteries. When thick plaques have established themselves in your arteries it may be too late. The ideal time to get aggressive about blood sugar control is as soon as you see a slight elevation in your fasting blood sugar or see one hour values over 140 mg/dl when testing your blood sugar after meals.
In fact, it's my guess that the single best thing we could do to screen for potential heart disease would be to ask people to buy a cheap blood sugar meter and test their blood sugar one hour after eating ten different meals. If the test results show repeated readings over 140 mg/dl aggressive steps should be taken to lower blood sugar.
What are those steps? You'll find them here:
How to Lower Your Bood Sugar.
This technique looks so simple, it's easy to dismiss it. But give it a try. If you do, you may be shocked at how well it works. I hear from dozens of people each week reporting that it does just that--including nurses and even, occasionally, registered dietitians. They start with A1cs that range from only slightly elevated in the low 6% range to those that are as high as 13%. But every one of my correspondents reports that they are able to achieve normal blood sugars in the 5% range--and so can you.
Start with the dietary strategy described in the link above and if dietary change isn't enough ask your doctor about adding metformin, the only oral diabetes drug that has been shown over decades of research to lower the incidence of heart attack.
If your doctor brushes off your request for help in lowering your blood sugar and suggests that all you need is to take a statin drug, it's time to find another doctor.
NOTE: I'm hearing from a depressingly large number of people who when they ask for metformin are put on drugs that are very expensive combinations of metformin and new or dangerous drugs like Onglyza, Januvia, or Actos. These drugs cost literally 15 times as much as plain, generic metformin and there is no research that suggests they result in better long term outcomes.
Indeed, the high risk of dangerous side effects from all of these new, expensive, and heavily marketed drugs suggests the opposite. But because the true dangers of a drug don't emerge until very shortly before they go off patent given the enormous clout that drug companies have, and the sneaky aggressive ways they market them, your doctor is all too likely to prescribe them.
In particular, I'm appalled at how many newly diagnosed people with Type 2 diabetes are now being given Kombiglyze XR, a combination of metformin and Onglyza. Onglyza has been shown by the very studies its manufacturer for the drug approval process to be less effective than Januvia, a drug in the same class, and to produce a higher rate of dangerous side effects. (Details HERE).
The side effects of Januvia are already disturbing. A doctor who would prescribe an Onglyza-metformin combo drug is a doctor who is strikingly ignorant about diabetes medications and who poses a danger to your health.
May 16, 2011
As is true with everything involving diabetes the answer is not simple due to variations in individual blood sugar responses.
The reason we test one hour after a meals is to learn how high our blood sugar goes in response to the specific meal. So we want to be testing at the moment when our blood sugar is at its peak.
Studies tell us something about the average time it takes for the carbohydrate in our food to turn into blood sugar (carbohydrates are the main nutrient that causes elevated blood sugars). Such studies suggest that most Americans who eat our meals fairly quickly will see a peak somewhere between one hour and seventy-five minutes after we start eating. But because studies only come up with averages, they don't take into account individual variations--and you are, of course, an individual.
And when we move from group averages to individual response we learn that when the blood sugar peak occurs depends on a multitude of factors that include how fast we eat our meals, how much we eat at each meal, how tightly bound the glucose is in the carbohydrates we eat, and how efficient our digestive system is at digesting the carbohydrate bound in our food.
That explains why the same meal consumed at the same time by two different people may peak at different times--and why I can't tell you exactly when to test.
That's why you might try varying the time at which you test a carefully chosen test meal to see if your personal peak is later than average. Choose a simple meal that contains a known quantity of carbohydrate--a single measured portion of something rather than a meal where you have to guess what you are actually eating. Test it on different days at a slightly different interval each time to see if your blood sugar might be peaking a bit later than average.
FACTORS THAT CAN AFFECT WHEN A MEAL CAUSES A BLOOD SUGAR PEAK
There are a couple things to keep in mind when you are testing your meals.
1. Hard Pasta (the kind that comes in dry form in boxes) takes several hours to digest and often will cause no rise in blood sugars at one or two hours. If you eat pasta you should test it at three and four hours to find a blood sugar peak. So-called "fresh pasta", however, digests at the same speed as bread. As discussed HERE Dreamfields Pasta produces the identical blood sugar curves as much cheaper normal pasta.
2. Pizza eaten with crust may also produce a delayed blood sugar peak due to the high fat content and the food volume involved.
3. Most people are more insulin resistant at breakfast than they are later in the day so you may see a higher reading after eating a food at breakfast than you will see if you eat the same food at lunch, even if you start the meal with the same blood sugar level.
4. If your blood sugar is very slow to come down after eating you may have elevated blood sugars left from a previous meal when you start eating your next. If you see much higher readings after dinner than you did eating the same food at lunch it is possible this is happening. In that case, you might want to test before you start eating, and if you see a high reading then, you would be well-advised to avoid eating any starch or sugar with your next meal. Eating only meat, green veggies, cheese and eggs won't raise your blood sugar significantly when it is already elevated.
5. If you have a condition called "gastroparesis" in which the stomach holds on to food for many hours at a time, delaying digestion, it may be impossible to predict when your blood sugar will be at its highest. This is not a common condition. It can be a diabetic complication, but usually it is a very late complication that affects people with Type 1 diabetes who have had very high blood sugars for decades. However gastroparesis can also be caused by other things that have no relationship to diabetes, for example, a viral infection.
6. Januvia, Onglyza, and Byetta all cause delayed stomach emptying (usually accompanied by constipation or cramping). If you are on these drugs, you may be experiencing blood sugar peaks later than usual and should experiment with later testing times.
7. Pure glucose--the sugar used in glucose tolerance tests--is absorbed directly from the stomach without having to be digested by enzymes. Other sugars have to be digested which takes longer. There is a theory beloved by nutritionists that says that whole grains and "complex sugars and starches" digest much more slowly than other carbohydrates, too. My experiences and that of many people with diabetes is that there is a difference in the speed with which glucose (and things like maple syrup or honey which contain pure glucose) hit the blood stream but that starch is pretty much starch (except for pasta) and whole grains digest at the same speed as potatoes or white bread. A study you can read about here confirms this.
Once you establish the interval after eating at which your blood sugar is likely to be at its highest, you need only test at that time to assess the impact of a new food (or meal) on your blood sugar.
DON'T OBSESS ABOUT TESTING TIMES--OR EXACT READINGS
But don't make yourself crazy worrying about the timing of the test. Because of the shameful inaccuracy of our overpriced blood sugar strips the readings these strips produce can easily be off by 10-15 mg/dl (approx .5 mmol/L) when blood sugar is in the range around 100 mg/ld (5.5 mmol/L) and by a lot more if it is over 200 mg/dl (11 mmol/L).
So when you test, look for ranges rather than exact data points. Your goal when you start testing is to find foods that keep your blood sugar in the low 100s (6s) and to avoid those that push it up into the 200s (11s) at any time. Very small differences in your readings--120 mg/dl compared to 128--are not significant because they fall within the range of meter error.
What you don't want to see is readings that are consistently in the range of 160 mg/dl and higher (8.9 mmol/L) at one hour after eating or readings that don't drop below 140 mg/dl (7.7 mmol/L) at two hours after eating. And consistency is key here. Readings that are high day after day are what we have to avoid. But if you see one or two high readings occasionally, don't panic.
That's because diabetic complications come from prolonged exposure to high blood sugars: from many hours spent above 140 mg/dl every day for months and years. An occasional brief high won't make you go blind. It's the overall pattern that matters here.
WHICH IS BETTER, TESTING AT ONE HOUR OR TWO?
Both one and two hour readings are informative. The one hour reading tells us how high a food pushes our blood sugar. If we know how much carbohydrate there is in the meals that keep our blood sugar in the safe zone (learn what that is HERE) we can predict what other foods are safe to eat simply by looking up how much carbohydrate they contain. (You can find software and apps online that makes it easy to do this.)
The two hour reading tells us how efficiently our body was at getting rid of that temporary high. If it is elevated (over 140 mg/dl (7.7 mmol/L) it gives you warning that your blood sugar peak may be lasting long enough to start damaging your organs. If that is the case, you will need to cut back more on your carbohydrate intake or talk to your doctor about the safe medications that can help you achieve healthier blood sugar levels.
But it usually is a waste of time to talk to your doctor about your post-meal values until your readings are consistently over 140 mg/dl at two hours after eating. And even then they may dismiss your concern. That 140 mg/dl is the level that the American Association of Clinical Endocrinologists has set as the target that all patients with diabetes should be encouraged to reach. But most family doctors have been trained (by the American Diabetes Association) to believe that any two hour reading under 180 mg/dl (10 mmol/L) is "good control." This is, of course, why all the patients these doctors treat eventually develop diabetic complications, but it can be very hard to get treatment from a doctor who has absorbed this toxic ADA teaching.
WHAT ABOUT HIGH HALF HOUR READINGS?
There is one last, related issue that people write to me about which needs to be disposed of and it is this: If you test at half an hour after eating you are likely to see a high even if your blood sugar is completely flat at one hour. A surprising number of people write to me in a panic because they saw blood sugars over 140 mg/dl (7.7 mmol/L) half an hour or even fifteen minutes after eating.
A high shortly after eating is normal--as long as the reading has come down from that peak by an hour after eating. That is because, the way normal blood sugar control works, it may take a sharp brief spike in blood sugar to stimulate first phase insulin release.
But what makes a blood sugar response normal is that, in a normal person, as soon as this spike occurs, a burst of insulin is secreted which takes care of it completely. Blood sugar response is only considered abnormal if, after that initial blood sugar surge caused by glucose from a meal hitting the blood stream, the blood sugar level doesn't start heading back down.
You can see a graph of what happens to normal peoples' blood sugars when they eat a high carb breakfast HERE.
May 6, 2011
1. A mouse study confirmed that a ketogenic low carb diet (less than 70-100 grams of carbs a day) can reverse diabetic kidney disease.
Michal M. PoplawskiReversal of Diabetic Nephropathy by a Ketogenic Diet. Michal M. Poplawski et al. PLoS ONE, 2011; 6 (4): e18604 DOI: 10.1371/journal.pone.0018604
Explained here: Science Daily: Low Carbohydrate Diets May Reverse Kidney Failure in People With Diabetes
I hesitated to report on this because so much rodent research does not carry over to humans, however, I have heard anecdotally from enough humans who have reversed their own kidney disease over the years by eating a ketogenic diet and keeping their blood sugar completely normal, that it's nice to see some science suggesting it is indeed possible.
2. Another rodent study found that rats with heart failure did much better on a diet that was 60% fat. This makes sense since the heart prefers to run on ketones rather than glucose.Again, this is a rat study, so we have to be cautious, and the researchers are falling all over themselves to avoid concluding that their study proved that a high fat diet doesn't damage the heart--which was probably the opposite of what they set out to prove, but this is one more piece of evidence calling into question the theory that "eating fat will destroy your heart" theory so beloved by cardiologists.
Myocardial insulin resistance induced by high fat feeding in heart failure is associated with preserved contractile function.B. A. Christopher et al. AJP: Heart and Circulatory Physiology, 2010; 299 (6): H1917 DOI: 10.1152/ajpheart.00687.2010
Described here: Science Daily: Damaged Hearts Pump Better When Fueled With Fats.
3. Finally, a Spanish study found that sixty percent of a random selection of 2,270 adults attending a healthcare centre in Malaga, Andalucia, a region with one of the highest rates of cardiovascular disease in Spain were overweight and obese and had very high risks for cardiovascular disease. This suggests that there is nothing magical about the "Mediterranean Diet" that is usually described as the most heart healthy.
This does not surprise me. There is very little data supporting the healthfulness of this diet and what little there is was collected two generations ago. The few recent diet studies that purported to prove that the Mediterranean diet was healthy did so by comparing it with the "Froot Loops diet"--one made up entirely of junk food.
Though doctors always tell people to eat the Mediterranean diet, there is no study that compares the effect of a diet featuring significant carb restriction to the Mediterranean diet in terms of the effect on blood sugar or health outcomes. So don't let anyone talk you into eating pasta because it's "health food." It isn't. It's nothing more than a slow release glucose delivery system.
Prevalence of cardiovascular risk factors in an urban adult population from southern Spain. R. Gomez-Huelgas IMAP Study. International Journal of Clinical Practice, 2011; 65 (1): 35 DOI: 10.1111/j.1742-1241.2010.02543.x
Discussed here: Science Daily: Alarmingly High Cardiovascular Risk Factors Found in Mediterranean People
May 4, 2011
Here's the Kindle link:
Several of you have asked me for an e-book version, which is why I'm providing one. If this version proves popular, I'll do the work needed to convert the book to the other e-platforms. Unfortunately, the requirements for Nook and Sony Reader are completely different from those for the Kindle reader, and because the book is so rich in formatting, it's a job to do these conversions.
The Kindle version can also be read on iPads, iPhones, Blackberry and Android phones.
In response to your requests, I've also just uploaded a Nook version.