Does the food you eat affect the way you feel? From experience, I would say yes.
If you eat an enormous portion of greasy fish and chips the effect on your mood is often obvious and immediate.
Studies have linked higher consumption of fruit and vegetables to improved feelings of psychological well-being.
Researchers in Australia found that "Increased fruit and vegetable consumption [appeared] predictive of increased happiness, life satisfaction, and well-being". When participants increased their intake of fruit and vegetables to 8 portions a day their life satisfaction scores went up significantly. The studies were repeated in the UK and the researchers found the same thing but suggested Brits bump up their daily minimum to 10 or 11.
Eating more fruit and vegetables will make you happier. A systematic review of dozens of studies found that “every 100-gram increased intake of fruit was associated with a 3 percent reduced risk of depression.” If this is true, you should feel your mood lifting slightly after eating 1 apple!
How does meat consumption affect your mood? This probably isn't a straightforward question to answer but from my observations, eating meat drains your energy.
How do you feel after Christmas dinner? Awful? Well, that's always been my experience until I stopped eating meat. I'll admit, Christmas dinner is in no way as pleasurable as it used to be, but I feel a lot better afterwards.
Is there any science to back up my conjecture? Well, I'm not sure how much research has been done in this area but one study I found linked higher meat consumption with poor quality sleep. As sleep is critical to mental health it's not too much of a stretch to conclude that eating meat has a negative impact on the mind.
The effects of Alcohol on mood are so obvious and well studied that I don't need to mention them here but what about other beverages? The current scientific paradigm is materialist and reductive and so when I search for the effects of coffee on mood, Google gives me a bunch of studies on Caffeine instead. Scientists mainly seem to look at individual nutritional components rather than whole foods. Green Tea contains caffeine but it doesn't give you the crazed anxiety kick that coffee does. This might be because green tea contains other chemicals such as theanine.
I drink green tea every day and find it extremely helpful for Tai Chi and meditation. A cup of green tea makes me feel relaxed but also focused and enhances the pleasant feelings that Tai Chi practice gives me. However...not all green teas are equal in this respect. I buy Vietnamese pin ho green tea from Matter Wholefoods in Easton because it's the most calming tea I've ever had.
What about sugar? Well, too much of it has been linked to depression. Sugar occurs naturally in complex carbohydrates like fruits, vegetables and grains which also contain fibre. The Soluble fibre in whole foods helps control blood sugar levels. Refined foods have little or no fibre and so cause blood sugar spikes creating a host of problems including changes in mood.
Without the meat, dairy and sugar you're probably thinking that dinner at my house is an austere affair but it's not. True, my wife sometimes tires of the Quinoa and Hummus onslaught but it is very possible to make delicious food that is also healthy. Try replacing sugar with dates (or date syrup) and you'll find that it's perfectly possible to make convincingly sweet cakes and puddings.
Are there any specific foods that are particularly good for boosting one's mood? There's probably quite a few but here's just one, Cacao.
Many studies show that eating Cacao helps lower anxiety. It is high in magnesium and flavonols which lead to the production of serotonin, endorphins and tryptophans (all chemicals associated with elevated moods). Cacao also contains anandamide, a natural euphoric compound. You often hear about the benefits of dark chocolate but really it's the cacao that's good for you (Not the sugar). Is cacao just a fancy name for cocoa? No. Cocoa powder is cacao that has been heat-treated and has therefore lost some of its nutritional value.
The same foods that increase feelings of happiness are also beneficial to your overall health. Eat a diet rich in greens, beans, berries, nuts and seeds and all the other fruits and vegetables and you'll not only feel better but also probably live longer.
There is a lot of pleasure to be derived from drinking fine wine and eating rib-eye steak covered in cheese but it is short-lived and comes with a downside.
All I'm suggesting really is that you pay attention to how food makes you feel. Sometimes I eat crap and drink too much but I don't feel guilty because most of the time I don't. I'm off to make myself a suitably worthy lunch now but I'll endeavour to make it nice too.