Research has shown cocoa beans to be rich in a variety of mood-lifting ingredients. These chemicals are most concentrated in dark chocolate, which is why it is recommended over the milk or white varieties.
Dark chocolate is high in polyphenols, which are shown to improve cognitive function, said Pratt. Chocolate also contains phenylethylamines, a neurotransmitter that, in low levels, is associated with depression and in high levels can be associated with schizophrenia.
Phenylethylamines work by releasing endorphins in the brain and promote feelings of attraction and giddiness.
"Both sex and dark chocolate activate the same parts of the brain," Pratt said. "Why not combine them?"
Besides the chemically stimulating properties of chocolate, the sweet flavor and fat content can activate their own pleasure centers in the brain. No wonder Wonka's Oompa Loompa's wanted to be paid in cocoa beans.
Most high school children learn, through drug and alcohol education, that alcohol is a depressant — literally. Alcohol can dull your central nervous system and impair important brain functions. But that's not the only thing alcohol can dull.
"Sugar and alcohol elate momentarily while they shoot excessive sugar into the system … but the resultant insulin response drives the blood sugar to dive low, creating brain and ultimate mood changes such as anxiety, depression, hopelessness, and/or sadness," said Adele Puhn, a clinical nutritionist who has written extensively about diet.
When taken responsibly, a small quantity of alcohol can have calming, sedative effects. But while a glass of red wine with dinner may have a soothing effect after a hard day at work, downing martinis or scotch will do the opposite.
"Alcohol will help you go to sleep, but you will wake up rapidly," Pratt said, when the alcohol is converted to sugar in the body. Sleep disruption can contribute to feeling tired, anxious, and depressed. "You just want to be very kind and loving to yourself."
If an apple a day keeps the doctor away, some brazil nuts each day might keep the psychiatrist at bay.
Brazil nuts, native to South America, are rich in the mineral selenium. Though scientists are not certain of the mechanism, selenium is essential for maintaining a good mood and getting enough selenium may prevent depression.
These rich nuts are also a good source of B vitamins, magnesium, and zinc, which can help calm stressed nerves and keep you alert.
Perhaps the spider that frightened Little Miss Muffet away was hip to the nutritional value of her curds and whey.
Whey is the natural byproduct of cheese. It is the thin, slightly cloudy liquid that is left behind once milk has been curdled and strained.
The mood benefits of whey come from the high concentration of tryptophan, that essential amino acid that gets converted to serotonin in the brain and lifts your mood.
If the thought of liquid whey does not set your mouth watering, it is often sold as whey protein, a powdered supplement found in health stores.
Maybe spinach helped Popeye the sailor strengthen up to fight for his love, Olive Oyl, but spinach has more effect on mood than Popeye let on.
Spinach is a potent green. Part of the family that includes kale and chard, spinach is a rich source of several minerals that are good for anxiety and depression.