Eating raw carrots and spinach can boost ward off depression because they contain more ‘essential’ nutrients, a study suggests.
Scientists found raw vegetables – and fruit – are better for mental health than those which are cooked, tinned or processed.
People who eat more raw fruit and vegetables also had improved levels of psychological wellbeing, including positive mood and life satisfaction, researchers discovered.
Health campaigns have traditionally focussed on the amount of fruit and vegetables people should eat, such as the five a day message.
But the new study, by researchers in New Zealand, implies that the way in which they are prepared is also important to consider.
Many people cook spinach and carrots, which is a major part of the traditional English roast dinner. However, fruits are often consumed raw.
Scientists found raw vegetables, such as carrots and spinach, are better for mental health than those which are cooked, tinned or processed
Dr Tamlin Conner, from the University of Otago, led the study, which analysed the eating habits of more than 400 adults.
She said: ‘Our research has highlighted the consumption of fruit and veg in their “unmodified” state is more strongly associated with better mental health.’
This was compared to cooked, canned or processed fruit and vegetables, according to the study in the journal Frontiers in Psychology.
This could be because cooking and processing of fruit and vegetables can cut their nutrient levels, Dr Conner suggested.
She said: ‘This limits the delivery of nutrients that are essential for optimal emotional functioning.’
Participants in the study were aged between 18 and 25 – the age group that has the lowest consumption of fruit and veg, on average.
Their typical consumption of raw, cooked or processed fruit and veg were assessed, and they were quizzed on their mental health.
Other factors that can play a part on mental health were studied, such as exercise, sleep, chronic health conditions and overall diets.
The study showed that people who consumed more raw fruit and vegetables had lower mental illness symptoms, such as depression.
They also had improved levels of psychological wellbeing, including positive mood and life satisfaction, researchers found.
These mental health benefits were significantly reduced for cooked, canned, and processed fruits and vegetables.
Dr Conner said: ‘This research is increasingly vital as lifestyle approaches such as dietary change may provide an accessible, safe, and adjuvant approach to improving mental health.’
The study comes after a nutritionist told DailyMail.com that chopping vegetables before eating them boosts their nutrients.
Carly Feigan, New York-based nutritionist and owner of Head to Health, said slicing the veggies can release healthy enzymes that support digestion.
Raw
Fiber 3.6 g
Vitamin C 7.6 mg
Potassium 410 mg
Cooked
Fiber 2.3 g
Vitamin C 2.8 mg
Potassium 183 mg
Ginger gives up its nutrients to the body much more readily when it is cooked, so you only need a quarter of a tablespoon of the spicy root cooked, compared to a full raw tablespoon
Raw
Vitamin C 0.1 mg
Magnesium 0.9 mg
Potassium 8.3 mg
Cooked
Vitamin C 0.4 mg
Magnesium 9.7 mg
Potassium 70.5 mg
Kale yields just a little more nutrition when it is cooked, so you need just a little less than two cups of the superfood to make a cooked version of a detoxifying dish
Raw
Fiber 4.8 g
Vitamin A 1,134 IU
Vitamin C 162.4 mg
Cooked
Fiber 10.4 g
Vitamin A 4,828 IU
Vitamin C 202.4 mg