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Blood Glucose and Diet

I just got one of these cool little devices that you use to monitor your blood glucose. It is absolutely fascinating to play with. I can monitor my blood glucose before and after a workout and see what different meals do to my blood sugar. The device is fairly cheap (about $60, but they really nail you with the supplies, the test strips and lancets.) Anyway, I want to monitor how my diet affects my long-term blood glucose levels. I’ve figured out what my average personal fasting glucose level is and I want to see if it changes with diet. Does anybody know how long you have to maintain a changed diet before you’ll see a change in the average fasting glucose level? Can I expect my “set point” to change in a matter of days? Weeks? Months? I hope somebody has some more experience with this and can help.

Depends on what you are changing in your diet. I noticed a significant decrease in fasting glucose levels after about 2 months of 6g/day EPA/DHA. Supposedly research shows it takes about 52 days for cell membranes to change and become more sensitive to insulin. If you are talking about consuming lower GI/II foods I would assume about the same time period.

Thanks. I’ll save money on those test strips if I’m not checking all the time. I’ll assume it takes a nice round 60 days to see some changes and monitor accordingly.

Another intresting note: I have found that pickle seeds may increase insulin sensitivity by up to 300% in adult males.

Ha! Whoever wrote that last one (JW) didn’t capatalize the “D” in my last name, a mistake the true Marc would never make.

Back to the point, don’t just track fasting glucose, but check for improvements in glucose challanges, like drinking gatorade and seeing how long it takes glucose to peak and return to baseline, the quicker the better.

Mark is exactly right. Doing regular glucose challenge tests (by ingesting a constant amount of carbs) on an empty stomach will give you great information.

You'd test right before you eat, 1 hour later and 2 hours later. You could test more frequently like every 30 minutes assuming that you have the cash, but it may not be necessary just to see improvement. BTW, whatever you eat should be cleared by 2 hours - even if it is Thanksgiving.

Hi Jason, is there any studies that prove that everything clears your stomach in 2 hours no matter how much you eat? I find this hard to believe.

I just visited my doctor and he said my levels were a little on the high side, but quite acceptable considering the degree of control my body seems to have. He suggested doing a two hour glucose tolerance test at the lab so I have a baseline.


One of the experiments I wanted to try was to see how my body handles a dose of Surge. I was going to track my blood sugar pre-workout / pre-Surge, then about 15 minutes after the first dose of Surge (that is, after I stretch), again after the workout, and then one and two hours after the final dose of Surge. That’s five tests (about $3.75 in test strips.) Do you think a scoop of Surge is a sufficient dose of carbs to test against?


Dr. Mercola thinks that a low fasting blood glucose is a good thing. Is there really any advantage to keeping fasting glucose levels low? I didn’t really understand his reasoning.

I’m not saying that all of the food is digested and cleared out of the stomach after 2 hours - I don’t know how long that takes. What I’m referring to is blood glucose clearance. I don’t have the references with me, but standard protocol for glucose screening or an oral glucose tolerance test notes that glucose should return to normal fasting levels (70-110 mg/dl) within 2 hours of ingesting food.

I just visited my doctor and he said my levels were a little on the high side, but quite acceptable considering the degree of control my body seems to have. He suggested doing a two hour glucose tolerance test at the lab so I have a baseline.

One of the experiments I wanted to try was to see how my body handles a dose of Surge. I was going to track my blood sugar pre-workout / pre-Surge, then about 15 minutes after the first dose of Surge (that is, after I stretch), again after the workout, and then one and two hours after the final dose of Surge. That’s five tests (about $3.75 in test strips.) Do you think a scoop of Surge is a sufficient dose of carbs to test against?

Dr. Mercola thinks that a low fasting blood glucose is a good thing. Is there really any advantage to keeping fasting glucose levels low? I didn’t really understand his reasoning.

Keep in mind that glucose uptake during and after exercise is significantly increased. This is a good test, but you should also do a similar test without the workout and compare those levels throughout the next couple of months. Check out the threads called “Fun With Glucose” from a while back, I posted some of my values with and without ALA combined with surge. Maintaining a low fasting glucose level is a sign that your insulin sensitivity is high, because excess glucose doesn’t float around in your bloodstream, it gets stored as liver/muscle glycogen. If your fasting levels are high, that means that glucose is struggling to get into your cells. I have been able to go from a fasting glucose of high 80’s to low 50’s through change in diet/supplementation alone.

Sorry about reposting your original reply yorik, that turned out to be a clusterfu%$ of a reply.

I can attest from following my glucose levels that I’m back to normal fasting levels after about 2 hours, so Jason is right.


Marc, how do you feel with a fasting glucose level down around 50? My nurse seems to think that much below 80 is too low, and the body can’t function well. Does a very low fasting level mean your body is operating on ketones instead? BTW, did you intend to copy my post into yours, or did the forum engine screw up?

From what I’ve seen, an optimal fasting glucose level is somewhere between 70-90 mg/dl. While I see a benefit to havning a low blood glucose, I don’t see much reason to try to take it as low as possible.

Like most things, I think optimal fasting glucose depends largely on the individual. I would agree with Jason, however, no point in trying to go too low. I feel like a champ in the mid 50’s, whereas someone else might be shaking and looking for a pixi-stick. An interesting area that doesn’t get much attention, good to see some people experimenting. I feel this is underused by trainers when designing nutrition plans. Of course 24 hour fatness wouldn’t allow such a dangerous procedure as a finger prick, but some of the non-corporate training gyms like the one I work at can get away with such tests.

yes, diet definately has an effect on blood glucose levels. carbs,yes, but mainly fat has the most/worse effect on blood sugar levels. it takes two months to see a change is hbac levels(that is a true test, your doctor can perform for longterm glucose levels} i am not sure this will work for a nondiabetic, because your body produces insulin. so no matter what you eat, your body will correct itself with the insulin(from your pancrease) with diabetics our bodies either, don’t make enough insulin, or no insulin at all. and that means we have to diet,excercise, and take insulin to regulate the bloodsugars. whenever you take a blood test(being anon diabetic) your blood sugar levels should always be in the correct levels (70-140} i hope this helps. if you have any more questions. or i did not properly answer. i will be glad to help. i have been diabetic 27 years. so maybe i can help you.

Wow, I got a lot of good information here. Thanks guys. I think it might make an interesting article for T-Mag to sum up all this information (including the “Fun with Glucose” thread) so people can find it all in one place. Any takers for authorship?

Well Yorik, I think you have an interesting idea. Obviously, having good control over glucose would seem to indicate excellent insulin sensitivity, but I’m not sure it is that simple.

Without concurrent measurements of insulin, it is quite difficult to know what is exactly going on in the big picture.

For instance, say Marc McDougal and I come fasted for 8 hours and drink a 75g glucose solution and measure our glucose pre drink, 30 min, 60 min, 90 min and 120 min.

Say our numbers start out the same and progress at the exact same rate. Well, on the surface, it would seem that we have the same glucose clearance and most likely the same insulin sensitivity. Well, I'll agree to the glucose clearance, but not necessarily with the insulin sensitivity.

Going back to the previous example, what if Marc and I could also measure insulin with our glucose measurements. Well, it turns out that while our glucose levels were identical, our insulin levels may be totally different. Say it takes twice as much insulin for me to keep the same glucose values as Marc. Marc's insulin sensitivity would be significantly better than mine.

Ok, I think I'm rambling a bit and it is more than likely that an improvement in glucose tolerance would imply an improvement in insulin sensitivity (what we are really after), but it's a bit scary to look at only one side of the equation although looking at glucose would be the only reasonably priced option.

Marc McDougal: To use a glucosetester in the gym would be good for the results but at least in Sweden the person who is doing these test must have some kind of medicaltraining (If they do the test on klients/custemers.). I think that in USA you must be aware of the risk for a lawsuit and must consider the risk even more.

To perform fingersticks in the US, you do not need to be a certified phlebotomist. Being that I’m in California (the state with the strictest guidelines), I had to go thru phlebotomy training before I was able to draw blood. But in other states, you don’t even need be a certified phlebotomist to perform venipuncture.

So obviously, you'd have to find out your state's laws. Most likely, you don't need be certified to perform fingersticks, but I might suggest going thru the process anyway so that you have the certificate if anybody asks.

But, then you get into another problematic area. Is glucose tolerance testing wellness or medical? If wellness, you don't need to have a physician prescribe the bloodwork. If medical, a physician is required to order all the bloodwork.

So, whether you could do this in a gym setting is really a question of your state's phlebotomy laws and how well you could describe the process as wellness testing. Because right now, I know that glucose tolerance has a clear medical bulling code and would more than likely be looked at as a medical procedure.

Jason, I couldn’t agree more with your thoughts on glucose vs. insulin discrepencies. Just as it was once thought that the glycemic index was always indicative of insulin release, we now know better. But like you said, it’s just not practical to test insulin on a regular basis although I wish it were.

Where would I look to find out specific laws pertaining to bloodwork in Colorado? Does anybody already know the laws? I do occasionaly perform fingerprick tests at a couple of different settings and would like to know if any legal implications exist. I always have clients sign a waiver but that may not be enough.

Yorik, I would like to see an article about this topic as well. Come on Berardi, you know you want to.