I thought this was a good article By Sara Reistad-Long

High in flavonoids, which are lauded for their relaxing properties (chamomiletea is another great source), chocolate also contains phenethylamine, a chemical that enhances your mood. The darker the chocolate, the more healthy substances you’re getting in your diet, so look for bars that are 70 percent cacao or higher.

Skim Milk

Turns out that a glass of warm milk really is calming. One study found that women who drank four or more servings of lowfat or skim milk every day were about half as likely to experience stress-related PMS symptoms than those who drank less than one serving a week.

Oatmeal

Carbs help you produce serotonin, a calming hormone that helps fight anxiety’s negative effects-which is probably why many of us crave them when we’re stressed. Go with the craving and choose healthy sources. Oatmeal is high in fiber, which means that your body will absorb it slowly. In one fell swoop, you’ll prolong the serotonin boost, keeping yourself feeling full for longer (and on less) and making sure your blood sugar’s in check.

Salmon

Research shows that omega-3 fatty acids-abundant in fish like salmon-can help reverse stress symptoms by boosting serotonin levels, and that an omega-3-rich diet can also help suppress the production of the anxiety hormones cortisol and adrenaline.

Walnuts

They’ve been shown to help lower blood pressure, which is critical for those whose hearts are already working overtime thanks to high adrenaline levels. In fact, research so strongly backs their health benefits that the U.S. Food and Drug Administration goes so far as to recommend 1 1/2 oz per day.

Sunflower Seeds

A good source of folate, which helps your body produce a pleasure-inducing brain chemical called dopamine.

Spinach

Studies show that magnesium, which you’ll find in leafy greens like spinach, improves your body’s response to stress.

Blueberries

Their antioxidants counteract the effects of stress hormones like cortisol on your body.