There are a lot of things that can be the underlying cause of a bad mood. A lack of sleep. Anxiety. Hunger. PMS. Alcohol. Depression. The consumption of too much sugar and/or caffeine. Stress. The list really does go on and on. But there's a theory I read recently about that triggers a bad mood that really caught my attention.

According to a researcher by the name of Roy Baumeister, the reason why a lot of us find ourselves not being in the best of moods is due to, what he calls, "ego depletion". The long short of it is, whenever we're tempted by something (or someone) and we push our willpower to the limit, it drains our cognitive abilities and that results in being irritable, snappy, distant, rude, annoyed—and all of the other things that come with being in a bad mood. (The ego is a trip, ain't it?) So, if you're currently in a bad mood, reflecting on your current struggles with temptation may be something to think about.

But, if you're usually on top of the world, it's been a couple of weeks now and, no matter what you do, you can't seem to get back to your old self again, avoid the urge to Google your way into a diagnosis; see your doctor instead. On the flip side, if you simply woke up on the wrong side of the bed or you know your willpower is running on fumes, there are also plenty of studies to support that your diet can make all of the difference in the world.

So, before you go ham on a co-worker or send a pop-off text that you very well could end up regretting, use your lunch break or make plans to go home to eat a few of these foods. It might be just what you need to get a smile back on your face.

Sweet Potatoes

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Did you know that sweet potatoes are considered to be a perfect food? With good reason too because they contain pantothenic acid (vitamin B5), niacin (vitamin B3), vitamin B6, vitamins A and C, potassium, manganese, magnesium, copper, beta-carotene, antioxidants and fiber—and that's just for starters! Thanks to all of the nutrients that are in them, sweet potatoes help to keep your heart healthy, boost your immunity, regulate your blood sugar, fuel your brain, reduce anxiety and, due to the fiber, iron and magnesium that's also in sweet potatoes, they are an awesome source of energy too.

There are two main reasons why sweet potatoes can make you feel better. First, the antioxidant beta-carotene that's in them will help to keep free radicals from damaging your brain. Secondly, sweet potatoes can lower oxidative stress which is directly linked to stress and anxiety.

Mood Booster: A "happy way" to enjoy sweet potatoes is to DIY some sweet potato flatbread (leave a comment in the comments section if you actually do end up making some because, I'm telling you, it's delicious!).

Salmon

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I don't know about you, but salmon is one of my favorite foods. It's got omega-3 fatty acids, is a wonderful source of protein, it contains just about every kind of B vitamin you can think of and it's loaded with both potassium and selenium. Something that's really cool about salmon is, thanks to the protein that's in it, it can help to control your appetite so that you can maintain your weight. It's also the kind of food that fights inflammation.

Salmon will put a smile on your face because, the more omega-3 that you consume, the more you increase the chances of not experiencing depression-related symptoms. Salmon also has the ability to keep your brain flexible; this matters because the more "flexible" your brain is, the more effective your brain's neurotransmitters are.

Mood Booster: One way to feel joy in your soul again is to try this honey-soy salmon recipe out.

Bananas

Photo by Jonathan Colon

Protein. Fiber. Potassium. Vitamins B6 and C. Manganese. Copper. Every time you eat a banana, this is what you're putting into your system. It's another kind of food that maintains blood sugar levels as it improves digestive and kidney health. Something else that's cool about bananas is if you're someone who works out, the potassium in this particular fruit is able to reduce muscle soreness and cramping. Bananas are also loaded with (the good kind of) carbohydrates which means that peeling one on your lunch break is one of the quickest ways to get you through the rest of the day.

One more thing—the tryptophan and folate that are in them will regulate your moods and help to reduce depression symptoms too. Eat up!

Mood Booster: Wanna get out of that funky mood in under an hour? How about some banana oatmeal pancakes for breakfast?

Olive Oil

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If you don't already have a bottle of olive oil in your pantry, cop a couple of 'em. Olive oil has omega-6 and omega-3 fatty acids, antioxidants, vitamins E and K and anti-inflammatory, antibacterial and anti-cancer properties in it. Bottom line, if you want to keep your heart, joints and brain in good shape, olive oil will help to make that happen.

On the good mood tip, olive oil is able to boost your body's serotonin levels. Serotonin is a neurotransmitter chemical that is connected to your brain's appetite, sexual desire, sleep, memory and yes—your moods.

Mood Booster: It's OK to treat yourself to a little bread (especially if it's naan or pita) every once in a while. When you do, lift your spirits with a little olive oil dipping sauce.

Quinoa

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Quinoa is a seed that is usually mistaken for a grain (including by me). Anyway, if you're looking for the kind of food that is pretty much a multivitamin in a bowl, quinoa's got you. For starters, it's got manganese, thiamine, zinc, phosphorus, folate, copper, riboflavin, magnesium, protein and vitamin E all up in it. If you're looking for a gluten-free food, quinoa qualifies as being that as well. A food that reduces body inflammation, quinoa can hook you up with that too. Quinoa is also the kind of food that keeps your bones healthy and strong.

Something else that's great about quinoa is it's the kind of food that is packed with protein, along with amino acids. So, if you know that lately you've been consuming foods that have your blood sugar levels on a roller coaster ride (eh hem, like basically any kind of white starch or sugar), you can rely on quinoa to level you out and stabilize your moods in the process.

Mood Booster: I don't know how you couldn't lighten up after having a mango quinoa burrito bowl.

Ghee Butter

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If you're not familiar with what ghee butter is, it's basically like a form of clarified butter; only it's simmered over heat a bit longer. The end result is the kind of butter that is packed with vitamins E and K, linoleic acid (a fatty acid that reduces body fat and inflammation), butyric acid (a fatty acid that maintains gut health) and Vitamin K2 that helps to keep tooth decay at bay.

Another awesome thing about ghee butter is it has ojas in it. If you take yoga, you probably know that an oja is an Ayurveda term that stands for "life force". They are what's able to reduce stress and detox the body from things that are related to poor diet and nutrition. So yeah, you can't go wrong with putting a teaspoon or two of ghee butter into your food.

Mood Booster: You can find ghee butter at your local grocery store (or on Amazon). But if you want to take a stab at making some at home, you can find a step-by-step recipe right here.

Seaweed

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Seaweed is a form of algae; that's true. But it's also a type of food that shouldn't be slept on. It contains iodine and tyrosine which is great for your thyroid, along with fiber, riboflavin, thiamin, manganese and copper. Something else that seaweed gives you is a good dose of the carotenoid fucoxanthin; it has 13.5 times the amount of antioxidants that are found in vitamin E and it's what protects cell membranes better than vitamin A does. (Just make sure to consume seaweed in moderation; especially if you have an iodine sensitivity.)

The reason why seaweed makes the "happy food list" is because it's another food that has a lot of tryptophan in it. The more tryptophan you have, the better (and sometimes sleepier), you'll feel.

Mood Booster: Love on yourself—and that mood of yours—with a little seaweed risotto.

Red Wine

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If you don't currently have a bottle of red wine in your house, get at least one. It's packed with antioxidants that fight off free radicals, it builds up your immune system, increases bone density, fights heart disease, reduces the risk of having a stroke, cancer and type 2 diabetes too.

And just how is red wine proven to improve your moods? Well, it releases the neurotransmitters including serotonin, dopamine and opioid peptides. After that happens, red wine gives you a euphoric feeling. Just make sure to try this tip once you get off work. Sometimes euphoria can be mistaken for tipsy or even lit, if you know what I mean.

Mood Booster: Got a little time on your hands? Make some vegan ragu that has red wine in it for you and a friend while sharing stories that will make each other laugh.

Honey

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Honey is literally one of the sweetest things for your health. Not only does it taste delicious, but the benefits are endless. Honey is full of antioxidants, can help to lower blood pressure and improve cholesterol levels, will give you an energy boost during the day and is a great sleep agent at night, suppresses coughing, manages weight, fights allergy symptoms, relieves nausea, improves diabetes, promotes good bacteria in intestines…girrrl, honey is pure bomb.

And yes, honey is another food that is able to get you into a good mood, thanks to the polyphenols that's in it. In fact, if you want to read how honey benefits you holistically, there's a pretty interesting study on it here.

Mood Booster: I'll just say this and then drop the mic: HONEY. LAVENDER. POPSICLES. **Are you smilin' yet?**

Raisins

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Nature's candy. A lot of us remember growing up and hearing that phrase as it relates to raisins, but what it all boils down to is it's dried-up grapes. What makes raisins a pretty cool snack is it contains iron, copper, B-complex vitamins, catechins (which fight off free radicals), fiber, magnesium and potassium. Something else that raisins have in them are polyphenolic phytochemicals which are not only antibacterial agents, but they are also great at maintaining eye health.

The reason why this particular dry fruit rounds out the lift-your-spirits list is because I recently read an article that said sad people tend to eat a lot of chocolate while happy people are constantly chopping on raisins. I'm not sure about all-a-dat but I'm not a scientist. Anyway, if you're feeling low, a handful of nature's candy is a lot worth a shot!

Mood Booster: If you like to watch someone prepare a meal and then make it yourself, you'll absolutely dig Tish Wonder's YouTube channel. The recipe that has plenty raisins in it is her red lentil coconut curry. Enjoy!

Featured image by Getty Images

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