What your sleep schedule says about what you eat, and how it affects your body
Hannah Wagner is a typical night owl.
The owner of Fortitude Valley wine bar Dark Red works late most nights of the week. Sleeping before midnight is a rare occurrence, as is waking up before 9.30am.
Like many night owls, Wagner skips breakfast and has trouble eating large meals before an active shift.
“I think a lot of hospitality workers would agree… you don’t want to eat a big katsu curry and try to work on your feet for six hours. That’s just the worst.”
Instead he chooses. Behind the bar, a can of tuna sat among spilled glasses of cold red. I race to the supermarket to grab a few slices of smoked salmon and fill the bar with mint.
Conscious of how unusual dinner times and a night owl lifestyle can affect weight and energy, Wagner sticks to basic meals after work.
“I don’t touch rice or pasta late at night… it’s just a tried and tested thing that I’m very aware of.
“I’m generally pretty good about making sure that the only sources of carbohydrates at midnight are vegetables and things like that.”
A recent study by Griffith University found that night owls tend to consume the same amount of calories as early birds, but consume less protein in the morning and consume foods higher in fat, carbohydrates and sugar late at night.
Combined with irregular sleep patterns and eating habits, they are at higher risk of impaired metabolic health and tend to have a higher percentage of body fat and higher blood sugar levels and lipids.
“Chronotypes influence our food intake preferences, behavior and metabolism,” says Professor Rozanne Kruger from Griffith’s School of Allied Health, Sport and Social Work.
Researchers analyzed data from 287 healthy European and New Zealand women aged 18 to 45 and assessed whether they had morning chronotypes (early birds) or evening chronotypes (night owls).
“This was an attempt to get a more concentrated look at what people eat when they eat. [and] their metabolic profiles,” says Kruger.
They found that early birds and night owls consumed similar amounts of food or energy throughout the day, but were influenced by the windows through which they ate.
Evening types consumed less food between 03:00 and 9:59 in the morning, while they consumed more food between 20:00 and 02:59 in the evening. The opposite was true for early risers.
After 8pm, night owls were more likely to turn to foods high in energy, carbohydrates and fat.
“What you eat is important, but when you eat is definitely important, too,” says Kruger.
“Speaking about the timing of meals, it is fine to have three meals throughout the day, although evening types may often or often postpone dinner to a later time than morning types.
“So six or seven in the evening is a good time [to eat dinner] but evening blizzards may push it to eight or nine in the evening.”
Kruger explains that consuming food at night when we should be fasting and sleeping means bodies store more food rather than using it, which can increase susceptibility to obesity and lead to poorer health outcomes.
“Energy in is equal to energy out, and once you take energy in, you either need to use it or store it.
“Targeting meal timing, especially reducing eating late at night, may be an important strategy for improving health among people with an evening chronotype.”
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