by Maria Mellor
We all have our little routines. We have lunch at a certain time, have a cup of tea in the afternoon, and go to bed around the same time of day. However with a hectic and unpredictable lifestyle these routines may vary drastically on a day-to-day basis. Researchers have found that disturbing your sleep-wake cycle can have a negative impact on your health.
Scientists believe that in the human body there are two ‘clocks’. The ‘master’ clock is made up of 20,000 nerves in the brain that connect to the eye signalling the body when it’s time to be awake and when to be asleep. It’s linked to temperature and hormone levels that fluctuate in a day-long cycle. There are also peripheral clocks in other organs, such as in the gastrointestinal tract where eating causes the clock to reset.
Biological clocks could have a bigger effect on our bodies than we might think. A recent study found that flu jabs for the elderly are more effective when given in the morning. The trial looked at over 300 pensioners and found that those who received their flu jab in the morning produced four times more antibodies to fight the virus.
Jonathan Ball, a molecular virologist at the University of Nottingham, said: “We know that a variety of factors, such as diet, sleep and exercise seem to impact on your immunity, but the fact that the amount of antibody produced following influenza vaccination differed according to whether or not the people included in the study were immunised in the morning or in the afternoon was intriguing.”
What time you eat also has an impact on the body. Studies have shown that people who ate their main meal of the day before 3pm lost more weight than those who ate later in the day.
Interestingly, research has found that cancer can disrupt certain circadian rhythms. Scientists looked at mice with cancer and found that these disruptions had a very bad effect on the liver. It seemed as if the liver’s usual functions along the circadian rhythm had been rewired to serve the tumour.
It has also been found that it’s down to genetics whether a person is a ‘morning person’ or not. The research found that of those who identified as ‘morning people, the majority of them had similarities within 15 parts of their genomes, with 7 of these parts directly relating to the maintenance of the circadian rhythm. It has been proven that diet and lifestyle can also be contributing factors as to when you are able to go to sleep and how easily you wake up in the morning.
While we know a lot about circadian rhythms, much of its causes and effects are still a mystery. There are such drastic variations from person to person for seemingly unrelated biological reasons that there could be even more underlying health effects that researchers are yet to find. Some studies have even shown that the culturally acceptable way in which we sleep in one block at night for 8 hours may not actually be for everyone – it’s all down to our biological clocks.