In the study employees consistently reported lower outputs in the winter season compared to the summer - with rainy days, gloomy workplaces and illness to blame.
Over two-thirds say they are less productive and have lower concentration, 69 per cent are less creative and half have less energy during winter compared to summer. While four in 10 people say they have lower energy levels in winter and a 66 per cent are more likely to comfort eat.
The office being too hot or too cold, ‘naughty’ snacks and treats and doing less exercise all make people feel less efficient in the office.
Only 12 per cent of those polled believe they work better in the winter than during the summer months.
Industry body British Summer Fruits explored how the different seasons affect workplace productivity and brain function in the study. The findings were in line with a recent neuroscience study conducted in Belgium, which revealed brain activity may follow a similar pattern to the Seasonal Affective Disorder, or ‘winter blues’.
British Summer Fruits have created a series of mind bending puzzles to keep ‘winter brains’ active during the colder climate.
People are invited to guess how many triangles appear in each shape - but the answer gets harder and harder.
The brainteasers are set to baffle Brits, who admit they find it harder to function properly in the winter months.
Laurence Olins, Chairman from British Summer Fruits, said: “There are several factors which contribute to workers feeling less productive and research suggests the change in seasons plays its part.
“More employers could encourage their staff to adopt a healthier diet, providing greater access to fruit in the office to prevent people reaching for sugary confectionary, particularly in these cold winter months.
“Eating healthily shouldn’t feel like a chore and snacking on fruits like berries can help with food cravings during the day due to their natural sweetness”.
During the colder months, 74 per cent of people find it harder to get out of bed for work and 37 per cent are far more likely to call in sick.
For two out of every five days in winter, Brits claim to feel under the weather - and 81 per cent admit they often go into work when they are unwell.
Two-thirds say they are likelier to indulge in unhealthy food than in the summer - with chocolate, biscuits, crisps and sweets readily available in the office.
But researchers discovered that to feel 100 per cent productive in winter, workers simply need to work six hours instead of eight, and have two breaks more than they would get during the summer months.
Flexible working hours, the opportunity to get fresh air during the day and access to healthy foods are also conducive to a positive work environment.
Other factors which could increase productivity are reduced background noise, the option to work from home and access to water during the day.
The food psychologist behind Channel 4’s Secret Eaters, Dr Christy Fergusson, said: “Relying on high sugar foods, biscuits and crisps to keep us going can leave us riding the blood sugar rollercoaster.
“We feel buzzed for a spell but soon our energy, concentration and mood can plummet.
“One of the best foods to snack on has to be berries. Not only are they loaded with antioxidants and highly nutritious, they are also low in sugar.
“You could say they are nature’s brain food. They pack a serious nutritional punch for every calorie consumed. This makes them the ideal way to supercharge your system with nutrients, without escalating your blood sugar levels.”