"We know that what we eat affects our physical health but the link actually about what you eat and your emotional and mental health is much more dramatic," said dietician Elizabeth Somer, author of, "Eat Your Way to Happiness."
Whether you're crabby, starving or just plain beat, take a look at what you ate or didn't eat in the past eight hours. Chances are, your nutritional choices played a role in your behavior.
"Literally what you eat for breakfast will affect how you feel by mid afternoon," said Somer.
Somer's motto is to eat food in their original packaging, meaning the less processed the better. That's especially true for carbohydrates that naturally contain water, fiber, plant chemicals and grains. It might not sound sexy but fruits, vegetables and whole grains are nature's anti-depressants.
"Carbohydrates can boost levels in the brain of a compound called serotonin. Serotonin is a little nerve chemical that when it's high you feel better, you're happier, you're more relaxed, you sleep better, your pain tolerance is higher," explained Somer.
"Basically, what you want to do is just eat a real foods diet 75 percent of the time and that means lots of dark green leafies, oranges, bananas, squash, whole grains, nuts, foods you know deep down in your heart are good for you," she added.
But there's more to the mood prescription; load up on DHA, found in omega three fats.
"Twenty years ago, we knew it was important to lower your risk for heart disease. Now, we've got this wealth of research to show that people that get enough of that particular omega three have a lower risk of depression, dementia even possibly Alzheimer's disease," said Somer.
You'll find DHA in fatty fish or foods that add it like yogurt and soy milk. If you want to take it in a supplement make sure you get at least 220 milligrams a day.
"Keep in mind that about 50 percent of your brain is fat, and of those omega threes in your brain almost 97 percent of them are DHA, which is a great big red flag to say this is the one you need to focus on, it's the most important for brain function," said Somer.
In addition, recent research shows vitamin D to be a near miracle nutrient with its effect on preventing depression, anxiety and even memory loss, yet 75 percent of us lack the amount we need.
Certain foods have it like fortified milk and juice along with salmon and tuna, but not in the levels we need.
And as we age, we become even more 'D-fficient.'
Somer reminds us to do three things: Spend at least 10 minutes a day with at least one body part in the sun as that's where you'll get a nice dose of it; eat foods rich in vitamin D; and take a supplement.
New guideline suggests we get at least 1000 international units a day.