Eating your way to happiness in the Philippines
Nestled at the back of a small courtyard in the north of Manila, there is a little restaurant with an unusual name and an even more unusual concept.
It is called Van Gogh is Bipolar, in homage to the Dutch painter who is believed to have had a life-long battle with mental illness, much like the restaurant's owner, Jetro Rafael.
Mr Rafael believes that certain foods can make you happy, and everything on the menu has been created with this in mind.
Ingredients such as salmon, honey, turkey and cabbage - all of which are thought to have mood-enhancing properties - have been worked into the dishes to create what Mr Rafael refers to as his "bipolar diet".
This is a very personal project. Mr Rafael said he developed his recipes after years of struggling with mood swings and depression.
"I started to look in books to learn how to manage my condition, and I found out about the properties of different foods. And now I want to share that knowledge," he said.
It is not just people with mental illnesses whom Mr Rafael aims to serve.
He also says his food can help those who just want to be a bit happier and calmer - perhaps they have had a stressful day at work, argued with their partner, got caught in Manila's terrible traffic or just feel a bit down.
"I see people come here who are tired and stressed, and when they leave I can see the difference," he said.
"The diet that I serve is designed and created to activate specific neurotransmitters in the brain, so these are neurotransmitters responsible for our feelings - feeling happy, feeling calm."
But how much of what Mr Rafael believes is scientifically proven?
According to nutrition experts, there is increasing evidence that he is right - food does have mood-altering properties - although this is still an area of science that needs to be better understood.
Dr Sandrine Thuret, from the Institute of Psychiatry at King's College London, says the omega-3 in oily fish and flavonoids like those in blueberries, cranberries and dark chocolate are thought to improve a person's mood.
She believes certain diets might work in a similar way to clinically prescribed anti-depressants.
"Prozac works by increasing neurogenesis (the creation of neurons) in the hippocampus in the brain. So perhaps some foods also increase the number of new neurons," she said.
And Jetro Rafael, while perhaps the first chef to devise a whole restaurant menu around the concept, is certainly not the first to link food to mood.
"Heston Blumenthal once came to our lab," said Dr Thuret, referring to a famous UK chef known for experimenting with food. "He wanted to know what was good for reducing stress and improving memory."
Dr Thuret says that to a certain extent, the turkey, bananas and nuts that Mr Rafael serves are likely to make people feel calmer and less stressed, at least in the short term.
These foods contains tryptophan, which is converted in the body into serotonin, a neurotransmitter that helps regulate mood.
But she is doubtful that just a few meals at Van Gogh is Bipolar will make a lasting difference.
"This is more a long-term investment, and on the whole, eating a healthy, balanced diet is what will make you most stress-resistant," she said.
And the old adage of everything in moderation still holds true.
"Eating a whole bar of chocolate every day is obviously not good," Dr Thuret said.
Chocolate does contain flavonoids, but unless it is almost pure cocoa, a bar of chocolate will also contain fat, and too much fat is known to lower the mood and ultimately reduce neurogenesis.
'Virginia Woolf's Tears'
Part of the difficulty of conducting research in this area is that a person's feelings are affected by so many factors, including their surroundings.
"Of course people will feel happier if they're somewhere they're being cared for," Dr Thuret said, adding that the ambience of a restaurant like Van Gogh is Bipolar could well be as influential as the food.
And certainly, as you walk in, it is easy to feel relaxed.
You are encouraged to make your own herbal tea while perusing the menu, and you are even offered a hat to wear from Mr Rafael's collection - my personal favourite has two stuffed birds glued to the brim.
The menu also makes you smile. Vincent Van Gogh is not the only famous name to put in an appearance. Most dishes are also named after people known for being somewhat temperamental, like Agatha Christie, Marilyn Monroe and Winston Churchill.
Courtney Love's Potion, intended to reduce anxiety, combines fruits, mint and honey. Virginia Woolf's Tears, aimed at staving off depression, is a turkey soup with cabbage and green apples.
The customers certainly seemed to be embracing the happiness vibe.
Mitch and his girlfriend Jeti had just finished a stressful work week, but sitting together wearing their chosen hats, they both had broad smiles on their faces.
"It's a great experience," said Mitch, adding that he was not sure what the essential ingredient was, and it did not really matter. "We're happy now, so I guess that's the most important thing."