[jluetjen]

I'd take a look at how much sugar your consuming at lunch time. Barring any events like jet-lag, as I've gotten older I've found that I'm pretty sensitive to the amount of sugar that I ingest. I'm not diabetic, but my blood sugar does spike up and then down before settling at a "normal" level. One of the swings makes me crash.

For example, my lunches are usually some unsalted or lightly salted nuts, some tomatoes, carrots and cucumber slices. If I snack on candy or have a meal with lots of sugar (like b-b-q sauce) I get sleepy around 2. If I skip that and keep to low sugar snacks and fresh fruit I don't have any problems.

BTW, I also avoid caffeine. I don't drink any coffee, tea or colas since I usually get sleepy when they wear off. If I don't drink them, there's no let-down. Since I usually work out for about 90 minutes in the morning when I wake up before 5:00, I never need any additional stimulants to help me wake up in the morning. The flip side though is that I'm usually pretty worthless by 10:00 PM.