I follow the Blood Type Diet food lists and exercise recommendations faithfully. But there are two areas where I haven't had the self-discipline to follow the program.

Both the Encyclopedia and Live Right talk about the importance of sleep and circadian rhythm. This seems to be especially important for Type As. Neither my daughter no my husband get enough sleep during the week. Then they try to make it up on the weekend. I'm encouraging both of them to get to bed earlier in the evening.

A recent experience indicates that Type Os shouldn't ignore getting a good night's sleep either. Disclaimer: What follows is one person's experience. I can't back it up with a scientific study. It falls under the category of anecdotal evidence. However, for me it sure seems to be true. A lack of sleep leads to weight gain and a few days with 8 hours of sleep leads to weight loss.

Last fall I wrote that I had mysteriously gained a few pounds.

They mysteriously vanished over the Christmas holidays.

They returned during yearbook deadlines.

They vanished when school was out.

During the summer I get more sleep than I do during the school year. I start out in September determined to get at least 7 hours of sleep a night, but by October that goal is abandoned. My weight was 128 in the summer, but climbed to 130 late in the fall. It disappeared when I got more sleep over the Christmas holidays. During yearbook deadlines I was often up late at night, and back came those two pesky pounds. They went away when school was out and my schedule relaxed.

Here is what made me take notice. I have been absorbed with an Internet research project. Several nights last week I stayed on-line until 2 or 3 or 4 in the morning. I still got up on time to send my husband off with a good breakfast and lunch. My weight popped up to 130. Over the weekend I made an effort to get 8 hours of sleep. My weight is back at 128.

I was reading in the BTD Encyclopedia about the effect of circadian rhythm on bone growth, skin rejuvenation and immunity - all of which are areas of concern for me. I must be more disciplined about getting to sleep on time at night!

The second area where I fail - - I'll blog about that soon!