Tuesday, November 20, 2007
Paleo Day Two: Cave Coffee
My inner caveman does not seem to want to exist without coffee. I can give up dairy, bread, rice, sugar, alcohol, chocolate, etc, etc, without any particular cravings or discomfort, however life without coffee seems intolerable.
I have been looking over some of the data on elevated insulin response due to caffeine ingestion, and, unfortunately, it seems equivocal.
Caffeine ingestion elevates plasma insulin response in humans during an oral glucose tolerance test.
We tested the hypothesis that caffeine ingestion results in an exaggerated response in blood glucose and (or) insulin during an oral glucose tolerance test (OGTT). Young, fit adult males (n = 18) underwent 2 OGTT. The subjects ingested caffeine (5 mg/kg) or placebo (double blind) and 1 h later ingested 75 g of dextrose. There were no differences between the fasted levels of serum insulin, C peptide, blood glucose, or lactate and there were no differences within or between trials in these measures prior to the OGTT. Following the OGTT, all of these parameters increased (P < or = 0.05) for the duration of the OGTT. Caffeine ingestion resulted in an increase (P < or = 0.05) in serum fatty acids, glycerol, and plasma epinephrine prior to the OGTT. During the OGTT, these parameters decreased to match those of the placebo trial. In the caffeine trial the serum insulin and C peptide concentrations were significantly greater (P < or = 0.001) than for placebo for the last 90 min of the OGTT and the area under the curve (AUC) for both measures were 60 and 37% greater (P < or = 0.001), respectively. This prolonged, increased elevation in insulin did not result in a lower blood glucose level; in fact, the AUC for blood glucose was 24% greater (P = 0.20) in the caffeine treatment group. The data support our hypothesis that caffeine ingestion results in a greater increase in insulin concentration during an OGTT. This, together with a trend towards a greater rather than a more modest response in blood glucose, suggests that caffeine ingestion may have resulted in insulin resistance.
I did find some pro-caffeine articles such as this one, by the Nestle research group in Switzerland. Grain of salt.
6AM 1/2 cup milk, coffee = .5 blocks
8AM 1 egg, 2 egg whites, 4 cups mushrooms, teaspoon olive oil, 1/2 grapefruit = 3 blocks
Noon 1/2 lb green beans, 6 oz ground buffalo, 1/2 apple, 1/3 oz nuts = 4 blocks
7PM Noon 1/2 lb green beans, 6 oz ground turkey, 1/2 apple, 1/3 oz nuts = 4 blocks
9PM 1/2 oz nuts
Block Target = 16 paleo blocks
Block Total = 12.5 paleo blocks, plus nuts
Paleo Rating = 97% (.5 block milk, medium coffee)
Clean and Jerk 3-3-3 reps (1/2 volume week)
OHSQ 120x15 (pr)
Bike ride 3 miles, flat, fixed gear, medium intensity