Running Like Clockwork

Life has a certain regularity for most of us and this is based on a twenty-four hour cycle, more or less. We get grumpy if it’s disrupted, especially if it’s early in the morning. But our circadian clock is rather more important than effecting our grumpiness when interfered with. Many other nasty effects have been indicated, such as cancer or diabetes.

The key issue here is that our metabolism is linked to our clock. Exactly how much is the question investigated by Dallmann et al who reported their findings last week in the Proceedings of the National Academy of Science (1).

Theirs was a pretty tough study, especially for their volunteer human lab-rats who were locked away and kept on a strict 40-hour cycle. They had to eat hourly isocaloric meals, no exotic menu choices for them. In addition they were shut away in dim light in enforced positions and kept sleep deprived. This way, their body would have no clues from TV, soft beds, or bright sunshine as to what it should be doing .

This meant that their metabolism would be running on the circadian clock only with no interference from competing stimuli. The only excitement was regular blood letting and saliva sampling to check the levels of the small molecules from their metabolic workings.

The levels of 15% of these small molecules varied in line with the subjects’ circadian rhythm. The molecules in question were fatty acids and amino acids. These are involved in important metabolic pathways. Think cell membranes and fatty acids, and DNA or proteins in general for amino acids and their importance is immediately clear.

What should we do about this? Clearly the old adage of “Early to bed, early to rise…” has a lot going for it, but is eating regular meals (like you mom told you) and not burning the candle at both ends all we need to know? Perhaps we should dig a little deeper to get in tune with our inner clockwork and fit our exercise and menus so that they match up.


Leave a Reply