Our daily sleep cycles, behaviour, and metabolism, are regulated by a powerful master clock in an area of the brain known as the suprachiasmatic nucleus. This 'circadian' clock, located in the hypothalamus, is controlled by some special brain cells, which, in turn, are highly sensitive to daylight. The suprachiasmatic nucleus coordinates our body's internal processes with the external environment, helping us maintain a regular sleep-wake cycle.

Because the body's biological clock can only shift a small amount each day, it takes the average person about a week to adjust to the new time zone after a transatlantic flight.

The traditional model stated that the clock and the brain communicated to the rest of the brain via the number of electrical impulses that the brain cells produced. These impulses would travel around the brain, telling it what time of day it was. These cells had been thought to be inactive during the day, but recent research by a University of Manchester team found the opposite true.

The brain keeps the body clock on track by firing more cells during daylight and very few at night. These findings are hoped to lead to new approaches to tuning our body clocks, such as light therapy or developing new drugs targeting the brain cells responsible for regulating the circadian rhythm. This new understanding may also pave the way to combating sleep disorders triggered by body clock malfunctions and help develop drugs to counteract things like jetlag.

Two types of brain cells

"We've found at least two types of cells in this part of the brain." Professor Hugh Piggins, an expert in neuroscience at the university, told the BBC World Service's Health Check programme.

One new cure for jet lag could be on the market a few years after clinical trials show a pill can reset the body's natural sleep rhythms.

Shifting melatonin

In trials published in the esteemed medical journal The Lancet, a drug called Tasimelteon helped troubled sleepers nod off quicker and stay asleep for longer by shifting the natural ebb and flow of the body's sleep hormone melatonin, which peaks at night. Experts said the drug would also be a welcome alternative to addictive sedatives.

Natural melatonin is a popular treatment for patients with body clock-related sleep disorders. Various melatonin products are often sold over the counter as non-prescription drugs, and researchers warn the potency, purity and safety of melatonin pills are mainly unregulated. Also, it needs to be more conclusive whether they work as shift workers or people with jet lag.

The new drugs, which work through the same neuro-receptors and pathways as melatonin, have shown promising results in improving daytime performance and alertness without any carryover sedative effect. This breakthrough offers hope for those struggling with sleep disorders and jet lag, providing a sense of reassurance and confidence in the future of sleep management.

Adjust your meal times.

Meanwhile, another study suggests adjusting meal times may help travellers recover from jet lag.

Harvard University researchers believe the brain has a second clock that keeps track of meal times rather than daytime. This discovery underscores the importance of understanding the relationship between the two clocks. By adjusting meal times, shift workers and travellers may be able to use the feeding clock to adapt to changes in time zones and avoid tiredness, empowering them with a new strategy for managing jet lag.

Thus, shift workers and travellers may be able to use the feeding clock to adapt to changes in time zones and avoid tiredness by not eating, the authors suggested in the journal Science.

"A fasting period with no food for about 16 hours is enough to engage this new clock," explained lead researcher Clifford Saper. "So, in this case, simply avoiding any food on the plane and then eating as soon as you land should help you to adjust and avoid some of the uncomfortable feelings of jet lag. It will never make the symptoms disappear entirely, but it could make them much more manageable." 

Showers

During extended stop-overs on a long-haul flight, showers are sometimes available. A shower not only freshens you up but also helps reset your body's internal clock by changing temperature and light exposure. This can help regulate your circadian rhythm and make you feel much better for the rest of the flight. Trans-Pacific pilots have told us taking a shower in Hawaii helps them recover more quickly from the general effects of jet lag after the flight. •