"Although the clinical relevance of magnesium in various tissues is beginning to garner more attention, how magnesium regulates our body's internal clock and metabolism has simply not been considered before. The new discovery could lead to a whole range of benefits spanning human health to agricultural productivity," added senior study author John O'Neill of the MRC Laboratory of Molecular Biology in Cambridge.
Magnesium -- a nutrient found in many foods -- helps control how cells keep their own form of time to cope with the day-night cycle. The discovery is expected to be linked to the body clock, which influences the daily cycle of sleeping and waking, hormone release, body temperature and other important bodily functions in people.
Researchers used molecular analysis and found that concentrations of magnesium rose and fell in a 24-hour cycle in all cell types and that this impacts on the cells' internal clocks.
"Internal clocks are fundamental to all living things. They influence many aspects of health and diseases in our body, but equally in plants and micro-organisms," said lead study author Gerben van Ooijen from the University of Edinburgh's School of Biological Sciences.
"It is now essential to find out how these fundamentally novel observations translate to whole tissue or organisms, to make us better equipped to influence them in complex organisms for future medical and agricultural purposes," Ooijen added in the paper, published in the journal Nature.
The team examined three major types of biological organisms -- human cells, algae and fungi. They found in each case that levels of magnesium in cells rise and fall in a daily cycle and this oscillation was critical to sustain the 24-hour clock in cells.
They were surprised to discover that it also had an enormous impact on metabolism in cells -- how fast cells can convert nutrients into energy -- throughout the course of a day.
The surprising discovery may aid the development of chronotherapy -- treatment scheduled according to time of day -- in people and the development of new crop varieties with increased yields or adjustable harvesting seasons.