You’d think the holidays would be a joyous time. That’s the idea: festivities, celebrations, hall decking and merry making all around. But all that cheer – and sugar, and wine, and stress – can lead to holiday blues.

During the holiday season, keeping up with self-care routines – exercise, meditation, adequate sleep – is especially vital. And don’t forget nutrition; the food you eat has a profound impact on mood.

Your brain is a chemical factory that constantly produces neurotransmitters – serotonin, dopamine, norepinepherine and endorphins that have a great impact on mood. A shortage or imbalance in these neurotransmitters can lead to depression. And the raw materials for these processes are amino acids, vitamins, minerals and other nutrients.

So feed your head with a handful of key brain nutrients, and you’ll dramatically impact your ability to process stress – and stay jolly. Here’s a list:

Good for you:
L-tryptophan is an amino acid that the body uses to make serotonin, the soothing brain chemical that keeps you from snapping at the shopping mall.

Good sources: Turkey, cheese, chicken, fish and oats.

Tips: Cut leftover turkey into cubes and add to soups; roll chicken slices in a Romaine lettuce leaf instead of bread, with a smear of stone-ground mustard and a slice of avocado.

L-tyrosine is an amino acid that helps the brain make norepinephrine, the happy brain chemical that keeps you smiling and upbeat in the holiday madness.

Good sources: Avocados, bananas, chicken, turkey, fish, peanuts, yogurt and pumpkin seeds also contain L-tyrosine.

Tips: Toss tamari-roasted almonds with chopped kale, avocado cubes, a handful of goji berries, and a drizzle of olive oil; core an apple, stuff the hole with peanut butter, and then cut the apple crosswise into slices; stir frozen blackberries into a dish of organic Greek yogurt.

Vitamin B6 (pyroxidine) plays a major role in converting amino acids into neurotransmitters.

Good sources: Fish, chicken, bananas, beans and peanut butter.

Tips: Toss chickpeas with olive oil and curry powder, and roast until crunchy; puree frozen bananas with a spoonful of peanut butter and a scoop of raw cocoa powder.

Vitamin B12, like pyroxidine, is crucial for converting amino acids to serotonin and norepinephrine, and is a factor in forming SAMe (S-Adenosyl methionine) a brain chemical that’s involved in neurotransmitter production and function.

Good sources: Eggs, chicken, crab, oysters, turkey, tuna, yogurt and salmon.

Tips: Mix hard-boiled egg yolk with mashed avocado, instead of mayonnaise, and stuff the whites with the mixture, for healthier deviled eggs; combine crab meat with mashed artichoke hearts, olive oil, diced red peppers and goat cheese, bake until bubbly, and serve as a dip.

Folate is also important for forming SAMe, serotonin and norepinephrine. Folate deficiencies are consistently linked with depression, anxiety and, in severe cases, schizophrenic behavior. (Which may explain some of our holiday madness.)

Good sources: Pinto beans, spinach, black beans, chard, turnip greens and asparagus.

Tips: Cook red lentils with coconut milk and Indian spices; roll mashed white beans mixed with sautéed vegetables in chard leaves, dolmas-style.

Magnesium is used by the brain to make serotonin and other neurotransmitters; magnesium deficiencies are common in people with depression, and adequate intake may help treat anxiety and insomnia.

Good sources: Spinach, oat bran, barley, pumpkin seeds, artichokes, leafy greens and beans.

Tips: Braise chard, minced garlic and red pepper flakes in olive oil; stir baby spinach and diced tomatoes into white bean soup just before serving; combine kale with honey, orange juice and chopped almonds, and roast in a hot oven.

Zinc is crucial for producing GABA, a brain chemical that eases anxiety and irritability. Studies have shown that chronic anxiety can exacerbate depression, and may manifest in what’s known as anxious depression.

Good sources: Oysters, crab, lentils, pumpkin seeds, yogurt, barley and turkey.

Tips: Broil oysters on the half-shell with spinach, Parmesan cheese and Pernod, Rockefeller-style; top pureed roasted winter squash with toasted pumpkin seeds.

Vitamin E keeps nerve cell membranes flexible, allowing smooth transmission of information. When cell membranes are hard or rigid, neurotransmitter communication is disrupted, and studies have linked low levels of vitamin E with depression.

Good sources: Sunflower seeds, eggs, tomato sauce, hazelnuts and almonds.

Tips: Top salads with sprouted sunflower seeds and toasted sunflower seeds; make spicy homemade ketchup by cooking down chopped tomatoes mixed with vinegar, chipotle peppers and a little honey.

Omega-3 fats, like Vitamin E, keep cell membranes flexible, improve oxygen levels in the blood, and thus stimulate conversion of amino acids into serotonin, dopamine and norepinephrine. Studies also show that omega-3 fats help prevent mood disorders and depression, especially in older people.

Good sources: Salmon, walnuts, flax seeds, tuna and sardines are also good sources of omega-3s.

Tips: Wrap strips of smoked salmon around chilled, steamed asparagus and serve with wasabi dipping sauce; broil sardines with a mixture of chopped fennel, red peppers and black olives tossed in olive oil.

...and not so good:
When you’re battling the blues, what you avoid can be as important as what you eat. Certain foods and food chemicals disrupt neurotransmitter function and alter brain chemistry. Steer clear of these brain drains:

Sugar causes a rapid rise and drop in blood sugar levels, leading to mood swings and depression. Avoid simple sugars, including honey and agave, and refined carbs, and eat adequate protein at meals.

Coffee. More than four or five cups a day can block serotonin in some people (but low to moderate amounts boost performance and improve mood). Limit your caffeine intake to one or two cups a day.

Artificial sweeteners. Aspartame (Nutrasweet) is an excitotoxin, much like MSG. In the brain, it upsets overall neurotransmitter balance and hampers the transmission of information.

Alcohol. More than two drinks a day can exacerbate depression by slowing neurotransmitters and disrupting sleep, which is necessary for serotonin production. Limit drinking to an occasional glass of wine or beer, especially if you have a history of depression or mood disorders.

Lisa Turner is a food writer, intuitive eating coach, and cooking and nutrition instructor at Bauman College of Nutrition and Culinary Arts in Boulder. Visit her websites at www.TheHealthyGourmet.net and www.InspiredEating.com.