Mon, Oct-28-19, 04:05
Darker days getting you down? Food can boost your mood but depends which ones you eat
Darker days getting you down? Food can boost your mood, but it depends which ones you eat
If you’re grumpier or sadder during the winter, you’re not alone. Danish scientists have found that in the month after the clocks go back there is an eight per cent rise in incidences of winter depression also known as Seasonal Affective Disorder.
The good news is, whether you suffer with low mood all year around or only as the winter sets in, there’s new scientific evidence that shows what you eat can substantially boost your mood.
The antidepressant food scale
In 2018 the link between food and mood was brought home in research published in the Journal of World Psychiatry which published an Antidepressant Food Scale. Scientists came up with a list of foods that ‘are the most dense sources of nutrients demonstrated by the scientific literature to play a role in the prevention and recovery from depressive disorders.’
The biggest contenders? Watercress, at 127% followed by spinach at 97%, swiss chard at 90% and mustard, turnip or beet greens which ranged from 76-93% - kale was on there but not as high as you would think at 48-62%. Oysters at 50% got a good run too.
Now a new field of nutritional psychiatry is unravelling the relationship between what we eat and how we feel. One of its pioneers, Professor Felice Jacka, a nutritional psychiatrist and head of the recently created Food and Mood Centre at Deakin University in Melbourne, Australia released a book on the subject in July this year.
In Brain Changer: The Good Mental Health Diet she says: ‘From all the research to date, we can safely say that the quality of adults’ diets is related to their mental health,’ she asserts. ‘Diets higher in whole foods such as vegetables, fruits, wholegrain cereals, beans and legumes, nuts and seeds, fish and olive oil are consistently associated with a reduced risk of depression. Diets higher in sugar-sweetened drinks, processed foods and refined carbohydrates are consistently linked to a higher risk of depression.’
So far, so obvious. But her research has also led Prof. Jacka to conclude that there are a number of mood-friendly ways to eat. ‘Traditional diets such as the Norwegian, Mediterranean or Japanese diets are all associated with better mental health outcomes,’ she concludes. The latter is reflected in other research, such as one study published in the journal PLOS Medicine that found Japan had the lowest rate of depression in the world, followed closely by Australia where the Mediterranean & Asian diet is dominant thanks to the large population of people with Italian or Greek descent, and its proximity to Asia.
The oily fish factor
One thing the diets of Norway, Japan and the Mediterranean have in common is a high consumption of oily fish – think sardines, mackerel, herring, salmon and trout. But in Britain our consumption of such fish is staggeringly low, with a recent study commissioned by Efamol (makers of omega-3 supplements) finding that one in five of us never eat oily fish and a staggering quarter of us haven’t eaten it in the last six months.
Nutritionists say we should consume two portions of fish a week
Of course, it’s impossible to prove causality, but in the last decade, prescriptions for antidepressant medications doubled and in Britain were at record numbers last year. In fact, the reason nutritionists are always on at us about consuming two portions of oily fish a week is because it’s rich in omega 3 fatty acids. ‘These essential fats make up the external membranes of the brain’s neurons and they’re something people with depression are often lacking’, says Prof. Jacka.
But why oily fish in particular? ‘They’re rich in specific types of Omega 3 fatty acids known as Docosahexaenoic Acid (DHA) and Eicosapentaenoic Acid (EPA) which our bodies can’t make, and which are prevalent in the brain,’ explains Lucy Perrow, state-registered dietitian and spokesperson for the British Dietetic Association.
‘People with depressive symptoms have been shown to have low levels of EPA in particular, which is abundant in foods such as salmon, mackerel, herring, trout and fresh tuna.’ If oily fish isn’t your thing, you can take a quality omega-3 supplement, but make sure it contains EPA and DHA. ‘In fact, if you are clinically depressed, research has shown good outcomes for people taking omega-3 supplements alongside their antidepressants.’ One such supplement is Higher Nature’s Omega 3 Fish Oil which contains 180mg EPA and 120mg DHA per capsule (£9.55 for 90 capsules) but Perrow advises talking to your doctor first as these can interfere with some medications.
Even if you don’t take antidepressants, but suffer with low mood, high levels of omega-3s can help alleviate low mood, says registered nutritionist Robert Hobson. One meta-analysis looked at 10 double-blind, placebo-controlled trials on omega-3 fatty acids’ and concluded they did indeed have significant antidepressant effects.
‘The doses used in the studies are usually high [500-1000mg EPA alone or EPA combined with DHA] so in reality getting enough would involve eating oily fish a few times a week and topping up with a daily supplement,’ Hobson advises. Do note that if you’re pregnant, the NHS recommends not eating more than two portions of oily fish because it can contain pollutants harmful to a growing baby.
Fix the IBS, fix the depression
Some specific diets help depression – but by default. For example, one recent study published in the journal Nutritional Clinical Practice found that patients with irritable Bowel Syndrome (IBS) – which affects a staggering one in five people, mostly women - who were put on a low FODMAPs diet (a highly researched diet for IBS that excludes a number of foods including fermentable vegetables, wheat, sugar and gluten) not only saw their IBS improve, but also showed improved ‘happiness and vitality’ and a lowered incidence of anxiety, depression and fatigue.
But this doesn’t mean that you should try a low FODMAPS diet if you don’t have digestive issues.
‘One aspect of this result is the psychological impact of IBS which has been shown to leave patients feeling more depressed and anxious than non-sufferers,’ says Hobson.
But people with IBS are often depressed and anxious as a result of their condition, so ‘the association doesn’t go beyond this – we can’t infer from it that the low-FODMAPs diet could help depression and anxiety in those without IBS,’ he says.
Is your pasta making you depressed?
But then there’s the gluten connection. Low-FODMAPs diets necessarily avoid all gluten – a protein found in bread and wheat foods such as pasta - and one thing Robson is convinced about is the link between increased mood disorders in people with gluten related disorders such as coeliac disease (people with coeliac disease have an immune response to all foods containing any gluten).
Gluten is a protein found in bread and wheat foods such as pasta
And, in a 2018 meta-analysis of the research scientists concluded that there is indeed an association between mood disorders and gluten intake and even went so far as to say that ‘the effects of a gluten-free diet on mood in people without gluten-related disorders should be considered in future research.’
The reason for this is not understood, Hobson points out, but some of the theories suggest that an immune response to gluten may lead to depressive symptoms. Indeed, looking at the research Hobson concludes, ‘though more research is needed, there is a fair argument linking low mood to gluten intake.’
That gut feeling
‘There is some evidence for gluten upsetting the balance of good bacteria in the gut and in some instances this may also trigger inflammation - both associated with an increased risk of depression,’ says Lucy Perrow. ‘If someone is gluten intolerant they may have a damaged intestinal wall which can then affect their absorption of nutrients from food that are vital to mood, especially vitamins B and D.’
But there’s a more direct reason why your gut health is not only essential to your mood, it may even dictate it (whether you have IBS or not). The gut is home to your enteric nervous system, sometimes referred to as the ‘second brain’. We’re still only at the very beginning of research into how this ‘gut-brain’ axis works but one theory is that the vagus nerve – a long, critical nerve extending from the abdomen to the brain – acts as a neural highway for chemicals made in the gut to get to the brain. In other words, chemicals that the microbes in the gut secrete could switch genes on and off in the gut lining, affecting the brain.
Moreover, ‘more than 90 per cent of our body’s serotonin [a key happiness neurotransmitter] is made in the gut!’ says Prof. Jacka. ‘One way this happens is because our gut bacteria influence the metabolism of tryptophan, an amino acid substance that is essential to the production of serotonin. ‘There’s now compelling evidence from animal studies that the gut microbiota influence depressive and anxiety-like behaviour and that changing the gut bacteria with specific probiotics can influence these behaviours.’
What to eat for a happier winter
Eat more antidepressant foods. Scientists have developed a list of foods with the highest antidepressant nutrients and the big winners are just about all green vegetables as well as oysters and organ meats. See more here:
Salmon, trout, herring, mackerel or fresh tuna twice a week: These oily fish are rich in omega 3 fatty acids which make up the outer membrane of the brain’s neurons – they’re often lacking in the brains of those with depression.
Fermented foods such as cultured yoghurt, kefir, kombucha, sauerkraut and kimchi: These are rich sources of healthy bacteria; key to the production of brain neurotransmitters such as serotonin, 90 per cent of which is believed to be made in the gut.
Broccoli, asparagus, artichokes, onions and garlic: These and many other fruits and vegetables are ‘prebiotic’ foods that act as fertiliser for the healthy bacteria in your gut encouraging it to grow; a bit like a garden. Other great sources include pulses, beans and legumes, which are great sources of fibre, also essential for gut health.
Green leafy vegetables (yes, we mean kale but also collard greens and cavalho nero): These are a great source of B vitamins, magnesium and iron; all essential to mood.
What we do know is that the more diverse the healthy bacteria in your gut, the more likely you are to produce serotonin, says Lucy Perrow. ‘Eating a variety of probiotic fermented foods such as sauerkraut, kimchi, kombucha and kefir can help increase healthy bacteria,’ she advises. ‘But it’s also important to consume prebiotic foods – these are what probiotics feed on and proliferate from – which act like fertiliser for growing your healthy bacteria’.
Prebiotic foods include almost all fruits and vegetables, especially onions, garlic, asparagus, bananas and artichokes. ‘It’s why I don’t advise a low-FODMAPs diet in people that don’t have IBS as it cuts out a lot of prebiotic foods essential to good mood just because they’re high in FODMAPS’.
If you want to take a probiotic pill, Perrow advises, look for one that contains lactobacillus and bifidobacterium cultures as these are the most researched in relation to mood. In fact, some specific strains are showing promise for mood. For example, four years ago a team of researchers at University College Cork (where scientists are at the forefront of studying the link between gut bacteria and mental health) found that men who took a probiotic containing a specific strain of probiotic called bifidobacterium longum for four weeks performed better in stress tests than those that took a placebo.
Don’t forget to top up your Ds
‘Vitamin D is essential for bone health, but low levels may also result in other signs including fatigue, tiredness and muscle pain,’ says Robert Hobson. In fact, as the best way to produce vitamin D is by the action of sunlight on skin those living in the UK are likely to be deficient, which is why the NHS recommends everyone over the age of five take 10mcg a day, especially between October and March.
‘The dark gloomy mornings, cold weather and long nights, teamed with low vitamin D levels can be a recipe for Seasonal Affective Disorder (SAD) or seasonal depression,’ says Hobson. ‘Despite the fact that food should always come first, vitamin D is one of those supplements that we should take regardless from when the clocks go back in the winter to when they go forward again in the spring.
We can’t synthesise adequate amounts of vitamin D from the sun during the winter and you won’t get everything you need from diet alone,’ he says.
Last edited by Demi : Mon, Oct-28-19 at 04:12.