Good Mood Food: Can you manage your mental health through your diet?by Rachel Kelly
In this extract from The Happy Kitchen, co-author Rachel Kelly explains how she does it.
There’s some evidence from animal studies to suggest that when our guts are inflamed, it can affect our mood. Some of the small proteins that control this inflammation are known as cytokines. Though these are important molecules for many bodily processes, if too many of them escape into the rest of the body from the gut, they may cause inflammation elsewhere. An elevated level of these cytokines has been linked with depression and is known as the “Cytokine Hypothesis”.
One way to reduce inflammation is to encourage healthy bacteria to flourish in our digestive systems. It is thought that an increase in the levels of unhelpful or “bad” bacteria that emit chemicals can compromise the lining of the intestine, leading to a fairly self-explanatory condition known as increased intestinal permeability, or ‘leaky gut’. This might allow some germs, toxins and small undigested food particles into the blood, leading to inflammation, intolerances and oxidative stress. However, this theory has not been conclusively proved and more research is necessary.
There may be a link between the bacteria in our digestive systems and anxiety. In the future, it’s possible that we will see the development of “psychobiotics”, a catchy word for specific strains of bacteria that may support mental health. Some gastroenterologists already prescribe treatments traditionally given to those with low mood, such as antidepressants and cognitive behavioural therapy, to patients with bowel disorders. It makes sense, given that our two “brains” are talking to one another.
So what do we need to eat to support a healthy gut? My approach has been twofold. First, cut down on the “bad” stuff, and second, increase the “good” – and please forgive these unscientific colloquialisms!
Sugar, antibiotics, alcohol, certain drugs, fatty cuts of meat, gluten, burnt food and processed foods are all thought to contribute to poor gut health. Like many alarmed by talk of gluten sensitivity, I was worried I was eating too much bread and that it might be damaging my gut and making me anxious.
Nutritional therapist Alice Mackintosh reassured me I need not give up on bread altogether. While she acknowledged the constant new research about sensitivity to gluten generally, she felt that for me, as for most people who don’t suffer from the medically recognised illness coeliac disease, a moderate intake of gluten from wholegrain sources around once a day would be fine. Furthermore, if I went completely gluten-free, I might risk vitamin deficiencies, in vitamin B in particular, and not be getting enough fibre, folic acid, iron and zinc.
Vary your carbohydrates
To increase the “good stuff”, start with anti-inflammatory omega-3s – salmon or other oily fish.
Second, vary your supply of carbohydrates. I am now wary of pasta, crackers, bread and cereal – which had all been favourites of mine. I realised that these made up nearly two-thirds of my diet on some days. I now choose quinoa, brown rice, beans, pulses, oats and starches from sweet potatoes or ordinary potatoes with their skins on for their fibre and nutrients.
Cooking food like wholemeal pasta, rice and potatoes and then allowing them to cool before reheating them changes the structure of the carbohydrate, leading to an increase in “resistant starch”, a form of fibre that provides a source of fuel for your good bacteria. Because this resistant starch travels through the digestive system nearly intact, it can also support regular bowel movements. These days I reheat leftovers of pasta, quinoa or beans as much as possible.
Third, boost your supply of fruit and vegetables that contain fibre.
A final point to note on what we need to eat for a healthy gut: we should ensure we eat enough prebiotic and probiotic foods, which help maintain the right balance of bacteria. Prebiotics are non-digestible foods that feed the growth of bacteria in the colon, found particularly in fermented vegetables and Jerusalem artichokes.
Probiotics are live bacteria and yeasts in yoghurt, dairy products and other foods, such as miso and kombucha, a type of fermented tea. They may also be taken in pills. Yogurt, ideally so thick it stands up in the bowl, is my own favourite probiotic.
When we are anxious, blood is pumped away from our gut, which has a negative effect on peristalsis (wave-like muscle contractions that move food along our digestive tracts). The muscles in our gut wall are sensitive, which is perhaps why a phrase such as “gut reaction” carries so much weight.
Exercise not only reduces our stress generally, but may also help our guts. Though doctors warn we must be careful of extrapolating animal studies to humans, some animal studies suggest that exercise may have a beneficial effect on gut immune function and microbiome characteristics.
As well as trying to nourish a healthy gut, I turn to particular minerals to help my anxiety levels, chief among them magnesium. Magnesium is involved in a variety of processes in our bodies, including normal muscle function and maintaining our bones. It can contribute to the normal functioning of our nervous system and might help memory and cognition.
One 2006 study has suggested that a magnesium deficiency may contribute to irritability, nervousness and depression. Magnesium may help to ease tension, and relieve muscular pain and headaches, which are common side effects of anxiety.
Leafy vegetables, sunflower seeds, wholegrain oats, quinoa and brown rice all contain the super-helpful magnesium. Magnesium can be found in raw cacao powder and to a lesser extent in a piece of dark chocolate.
Of all the discoveries I have made about nutrition in the last few years, this one has made me especially happy.
Cocoa products, including dark chocolate, may have some health benefit! Only the very good stuff, mind … In most chocolate, the potential benefit of some of these compounds is most likely outweighed by the sugar and fat content. Still, I have found it a relief to know I can enjoy a square of dark chocolate containing 70 per cent cocoa solids on occasion.
Almonds are another source of magnesium, so choose dark chocolate with almonds if you can.
Magnesium can be absorbed through the skin and Epsom salts are rich in it. Taking an Epsom salts bath is a nourishing tonic and a soothing way to wind down at the end of the day.
Vitamin B6 when anxious
Vitamin B6 is another stalwart that helps me when I am anxious. This may be because it plays a role in the synthesis of serotonin from tryptophan, though as we have seen, the evidence around the exact role of tryptophan is uncertain. Chickpeas, spinach, mushrooms, salmon and sunflower seeds are all rich in vitamin B6.
My food diary showed that my moments of panic frequently coincided with moments of hunger. This is a bit unusual. Many people I have spoken to say that normally they don’t feel hungry when they are anxious. Evolution would suggest that we would empty our stomachs in readiness to flee from a lion and eating would be the last thing on our minds.
But for me, the opposite happens. It is an important point. We are all unique when it comes to our response to food. So I have got into the habit of preparing calming snacks ahead. I usually feel nervier in the mornings, so I use my evenings to make snacks if I think the next day is going to be difficult. Preparing ahead calms me. Then I make sure I eat a snack every three hours or so. My panic dissipates when I do so in a most satisfactory way.
Inevitably, our busiest times are our most anxious times. I am thinking of Christmas, which leaves me frazzled. Yet the busier we are, the harder it is to manage our diet. This is rather ironic, since it’s when we’re busy that our bodies need healthy nutrients the most.
Edited extract from THE HAPPY KITCHEN, by Rachel Kelly with Alice Mackintosh (Simon Schuster, $39.99)
This article was first published in the May 13, 2017 issue of the New Zealand Listener.
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