Don’t let the weather become a weight on your shoulders
COLDER temperatures and all the extra time we spend indoors during winter provide a good excuse to eat more, and indulge in a few extra glasses of wine. But does the weather really influence what we eat or is it merely a fig leaf for our inherent gluttony?
The good news is the dreaded winter coat is not inevitable. Changing energy demands for activities like hibernation, migration and re- production among some mammals mean seasonal cycles of body weight are normal. But the absence of some of these seasonal behaviours in humans, along with modern conveniences, such as artificial lighting and climate control, mean the influence of cold weather on our eating behaviours may be overstated.
When we look at the average body weight of adults in winter and summer, not all studies report a difference. In research reporting changes, the differences are quite small: between 500g and 2kg.
But most of the research doesn’t tell us if the changes were increases in body fat (body mass comprises muscle, water, bone and fat). One study of healthy Dutch adults reported waist circumference (a good measure of abdominal obesity) was higher in winter than summer, among men and women.
Research has produced mixed findings on seasonal differences in diets among different groups of people. Some studies have not observed any daily energy intake changes with the seasons. Others have found people tend to consume more kilojoules a day in the cooler seasons.
A Spanish study of seasonal variations in food consumption, for instance, found the intake of cereals and alcohol was higher among men in winter than in summer. Women had higher intakes of dairy foods, including ice cream, in summer.
Fruit and vegetable intake also varied according to season, probably due to seasonal availability.
More time spent indoors during colder months means less physical activity, which is a common excuse used to explain winter weight gain. A US study, for instance, reported a small reduction in physical activity in winter compared with spring.
The reality is we have few sources of direct evidence as to whether temperature causes weight gain. It may, in fact, be the food myths of winter that are feeding into expanding waistlines.
But the key message is you shouldn’t use the changing seasons and cold weather as an excuse to eat badly and forgo a healthy lifestyle.