We've been talking about coffee and caffeine in the Daily today. We know that Dr. A says to keep your daily caffeine intake to no more than two servings (in a beverage) a day. Many of us find it hard to stick to that (i.e. 16 oz of coffee or caffeinated tea each day).
Just as Dr. A discussed in the SBD book, caffeine has serious effects on insulin sensitivity
( it tells how well the body is processing/using insulin to take blood sugar from the bloodstream). In a study, researchers found that caffeine (for women, about the same amount as in 1.5 cups of coffee) decreased insulin sensitivity by 15%
However, some are finding that coffee can have good effects on your insulin/possibilities of developing diabetes
. This is really confusing!
What seems to be the case is that caffeine
can cause problems with insulin, but coffee
can help reduce your risk of diabetes (there is more potential for this with men, however).
Here's a quote (somewhat lengthy...sorry!) from a very interesting discussion
on caffeine, insulin, and low-glycemic eating. (Skip the very technical discussion of caffeine at the beginning of the article if it makes your head hurt--the later stuff is much easier to understand!)
You can read more about the possibility that caffeine leads to insulin issues in these articles:
Caffeine Disturbs Blood Sugar Hormone
Look, there have been at least eleven human studies conducted using different methodologies demonstrating that caffeine intake has a negative effect on glucose disposal and acute insulin sensitivity. Let me give you a quick review of them ('scuze me while I pull out my notes):
— In Diabetes (2002), Thong et al gave a group of healthy, habitual caffeine drinking 20-somethings a big whack of caffeine (5mg/kg or about 350mg for a 70kg individual) after two days of caffeine withdrawal. In this study they wanted to determine the effects of caffeine on glucose uptake in an exercised leg vs. an unexercised leg...This measurement period occurred three hours after the exercise and one hour after the caffeine administration. Check out the results [look on the website for the chart]As you can see, although exercise increased glucose uptake/disposal in both groups, caffeine still blunts this effect. Talking percents, caffeine reduced glucose uptake by 55% in the rested and 51% in the exercised leg. In addition, whole body glucose disposal was 30% lower. Muscle glycogen synthase (the enzyme that promotes the storage of carbs) activity is also reduced.
— In Diabetes Care (2002), Keijzers et al administered caffeine to twelve healthy people and found that caffeine decreased insulin sensitivity by 15%. The authors of this study mentioned that the epinephrine increase seen with caffeine administration was probably responsible for the effect. In addition, the authors hypothesized that, just like with many of the other effects of caffeine, habitual caffeine use may not ameliorate this phenomenon....
I want everyone to be clear on something. I am in no way suggesting that caffeine use or coffee drinking will cause "clinical diabetes" or clinical insulin resistance. What I'm suggesting is that there are dozens of factors that affect insulin sensitivity (both acute and chronic) including exercise timing and mode, total caloric intake, macronutrient breakdown of the diet, food selection, drugs and medications, and time of day.
While some factors may be more powerful than others, I think it's important to recognize which factors increase insulin sensitivity and which factors decrease it. Once we know these factors we can strive toward making good lifestyle, exercise, and dietary decisions in favor of optimizing insulin sensitivity and glucose disposal in the muscle. Since I think the data are relatively clear on the fact that high dose caffeine decreases insulin sensitivity in healthy young people, we all need to be aware that coffee could present a problem for some individuals, especially those prone to diabetes, those without a regular exercise program, or those with poor dietary habits.
While caffeine intake certainly won't make you fat or diabetic, regardless of who you are, it may increase your glucose and insulin responses to meals and therefore thwart the effects of some of your low glycemic eating. But remember, dose is important. Small doses of caffeine may not be harmful. Timing is important, too. Taken immediately before exercise, caffeine may do some good things.
Caffeine consumption increases insulin resistance, study finds
(from Natural News)
Caffeine May Hamper Blood Sugar Control: Caffeine at Mealtime May Cause Problems for People With Type 2 Diabetes
Effects of Caffeine and Coffee on Diabetes, Insuln Resistance Syndrome & Hypoglycemia
(this is from a company marketing Teecino, a no-caffeine coffee, so they have a vested interest in the bad effects of caffeine. Therefore, take the information with a grain of salt. They do back up their claims with references to research studies, though--check out the bulleted section after the bold title, about halfway down the page.)
However, a moderate amount of coffee (or tea) can be GOOD for your health!
Here's some information on why:
All About YOU: A Brew for Better Blood Sugar.
(from RealAge) --Coffee might reduce your chance of developing diabetes by up to 25%!
That Morning Caffeine Fix? Consider It Health Care
(from RealAge) --about green tea and coffee
Coffee Talk: Some Surprising Health Benefits
(from RealAge) -- this has information about tea, too
Coffee Graduates to Health Food Status
(from RealAge) -- Coffee's beneficial effects on the liver.
article from RealAge can help you decide if coffee or tea is better for you...
If you have any other information, personal experience, or resources to share on this subject, post it here! We'd welcome your suggestions for how to cope with a reduced amount of caffeinated beverages in your day--how do you deal?
Personally, if I know I'm in a place where I'm likely to drink a lot of coffee, I try to drink cups of 1/2 caf/ 1/2 decaf, or drink two cups of regular and then switch to decaf. Mind you, decaf coffee still has caffeine
...it's just reduced to a small amount.
I find it really hard not to accept refills on caffeinated diet soda, though.
I often drink water with lemon in restaurants, but when I'm in the mood for soda...I usually give in. I try to go to places where they have diet decaf soda (Old Country Buffet has Sierra Mist Free, Panera has Decaf Diet Coke/Pepsi--I never remember which one--and US Air, which we usually fly, has Sierra Mist Free), but it's a pretty rare thing in most places. I need to get the nerve to ask for water after I've had two servings of soda...