Confused about coffee and diabetes

I read the Caffeine Roundtable (Strength Training, Bodybuilding & Online Supplement Store - T NATION) a while ago and left with the impression that caffeine decreases insulin sensitivity and thereby increases insulin resistance and JB states “coffee drinking will [not] cause “clinical diabetes” or clinical insulin resistance.” Confusingly enough, JB also says, “we all agree that sedentary individuals and those prone to diabetes are most at risk for caffeine induced insulin resistance.”

Then, this morning I hear a brief story on Good Morning America regarding coffee and diabetes. I say to my roommate, “look, the main stream media has finally caught up with T-Mag and JB!” I’m thinking the story will be about coffee and the increase likelyhood of type II diabetes. But no, according to GMA coffee intake will actually decrease chances of type II diabetes. And this article Coffee cuts diabetes risk.

I looked for the source of the reports and it appears to be Lancet. 2002 Nov 9;360(9344):1477-8 at PubMed Coffee consumption and risk of type 2 diabetes mellitus - PubMed.

Now, I’m really confused or just don’t understand diabetes and insulin. If I understand correctly, type II diabetes is caused by insulin resistance. But, these damn 7-cup a day habit Dutchers seem to be protected from type II by drinking a crap load of it. How can this be?

I saw that too, and the exact same question came to mind when I saw it.


I saw that story last night on the evening news, but I was at a restaurant and wasn’t able to hear the audio very well. I believe that the positive effects of coffee were not related to the caffeine but actually related to other substances that can be found in both regular in decaf coffee… but I’ll leave the details to the experts.

It’d be nice for the big man to comment on this.

yeah, there’s something fishy going on.

there was no mention as to whether or not the subjects injested de-caf or regular. (I still haven’t read the papers)

I know that caffeine is responsible for downregulating glut transporters which are insulin sensitive.

I don’t know man… fuckin scientists have their head way up their asses sometimes.

Type 2 diabetes is a disease characterized by insulin resistance. Coffee can cause temporary insulin resistance and make a non-diabetic’s blood sugar levels resemble a type 2 diabetic’s (probably during caffeine’s half life), but it won’t actually give a person diabetes.

The abstract at PubMed:

“Coffee is a major source of caffeine, which has been shown to acutely reduce sensitivity to insulin, but also has potentially beneficial effects. We prospectively investigated the association between coffee consumption and risk of clinical type 2 diabetes in a population-based cohort of 17111 Dutch men and women aged 30-60 years. During 125774 person years of follow-up, 306 new cases of type 2 diabetes were reported. After adjustment for potential confounders, individuals who drank at least seven cups of coffee a day were 0.50 (95% CI 0.35-0.72, p=0.0002) times as likely as those who drank two cups or fewer a day to develop type 2 diabetes. Coffee consumption was associated with a substantially lower risk of clinical type 2 diabetes.”

The article at Coffee cuts diabetes risk

"The researchers note that caffeine is known to reduce the body’s sensitivity to insulin, a phenomenon that should in fact worsen the diabetes problem.

However, coffee also has lots of chlorogenic acid and magnesium, which they speculate more than offset the effect of caffeine.

Chlorogenic acid, a substance called a phenol which plays a big role in coffee’s bouquet of flavour, has been found in lab tests to reduce absorption of glucose by the liver. Magnesium may improve sensitivity to insulin, they suggest."

The abstract appears to state that the subjects did consume caffeinated coffee.

Where is good ole’ JB on this?

I am hypoglycemic and really have to watch my caffeiane(sp?) intake, makes me really light headed and nausas from low blood sugar.

Mitch Green


"But how does a person’s coffee intake during the day affect diabetes-related processes?

To answer that question, Hu and his colleagues looked at two large studies involving 126,210 men and women. All had completed dietary and lifestyle surveys every two years for 12 to 18 years.

There were 1,333 new cases of type 2 diabetes in men and 4,085 cases in women, reports Hu.

They found that:

-Coffee intake lowered the risk of type 2 diabetes, and the lowering was independent of a person’s age, obesity, and other lifestyle factors that typically increase risk.
-Drinking more coffee had better effects: Those who drank six or more cups per day had the lowest risk of having type 2 diabetes compared with those who drank less coffee.
-Decaffeinated drinks and other caffeine sources had lesser effects on diabetes risk. While decaffeinated coffee seemed to offer some protection, decaffeinated tea did not.

Caffeine may stimulate muscles to burn fat and sugar more efficiently and could trigger the breakdown of fat in other tissue as well, Hu explains. Some studies have shown that caffeine does help with weight loss, he adds.

Also, coffee contains many other ingredients that could have beneficial effects on preventing type 2 diabetes – such as potassium, niacin, and magnesium, as well as antioxidants.

In fact, Hu says he believes the blood-pressure spikes found with caffeine may be short-term and that the body naturally adjusts to the jolt.

Though his study suggests long-term beneficial effects, it is too preliminary to prove a cause-effect relationship between caffeinated coffee intake and lower type 2 diabetes risk, Hu says. Don’t up your java intake – especially if you already have diabetes or heart disease."

The short term clinical trials which show coffee raises insulin resistance and the real life long term results ie less type 2 diabetes show the flaws in making too broad an assumption on a few weeks study results.
Much of the what the experts say as regards as to how and what to eat and reps and rest periods etc. are based on a very short term studys. I think most of what we read should be taken with a grain of salt. This isn’t to put down those making reccemondations but to realize most of what we read is based on assumptions from these short term studies.

Right, I’m thinking that, perhaps, the body is supercompensating for the acute insulin resistance and making up for it?