Scientists are not sure why this was the case, although have made some suggestions.
“Weight management is actually much more complex than just ‘energy in’ versus ‘energy out’,” says Professor Jennifer Kuk, of York University, Toronto, one of the author’s of the study that was published in the journal Obesity Research and Clinical Practice.
Factors that may play a role include changes in sleep patterns, stress levels, night-time light exposure, more pollutants in our food, higher maternal ages, reduced variability of ambient temperatures or changes to our gut microflora.
As the Guardian says:
The complexity of disentangling these potential causes probably means millennials will have become the object of resentment from their own offspring’s generation for their good fortune before scientists figure it out.
Bill Condie is a science journalist based in Adelaide, Australia.
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