The snowy, cold winter weather can make us all feel a bit down in the dumps, especially when it causes a serotonin imbalance. Serotonin is a neurotransmitter that is used by the brain to relay signals from one area to another. Serotonin production in our brain increases when light is present, so the lack of sunlight and warm weather during this season can leave us hungry for some happiness.

Plant-based eating can help boost our levels of feel-good hormones, which we may be in desperate need of in the dark, winter months. There are several amino acids and vitamins that can make us feel happier, all of which are found in plant-based foods. Maintaining a plant-based diet will help transform you into a more positive person. Here are five plant foods that can boost happiness levels and your positivity:

1. Sea vegetables

Sea vegetables contain tryptophan, which is an essential amino acid for the brain’s serotonin creation.  Tryptophan serves as a precursor for serotonin and plays a role in the production of nervous system messengers. Most sea vegetables contain 3.1 percent of your recommended daily value of tryptophan. Choose sea vegetables like kelp, seaweed, and spirulina for a positivity boost. Eat your spirulina in a Tropical Green Spirulina Smoothie.

2. Bananas

Bananas are high in vitamin B6, one of the crucial B vitamins for creating a positive outlook. The fruit contains a whopping 22 percent of your recommended daily value of B6. They also have a high serum concentration, which helps aid in serotonin production. Try cooking bananas into some Vegan Banana and Blueberry Brunch Bread.

3. Soy

Soy products such as soybeans, tofu, and soy milk contain nutrients that assist in stabilizing serotonin levels. Soy can contain 122 percent of your recommended daily value of tryptophan and 29 percent of riboflavin. It also has the amino acids tyrosine and phenylalanine. Tyrosine in particular is important for our positivity levels, since it is used to synthesize proteins while also helping to control concentrations of dopamine and norepinephrine. Try this recipe for Vegan Sesame Tofu, and remember to choose organic/non-GMO soy!

4. Nutritional yeast

Nutritional yeast is the perfect ingredient for making an uncheese sauce. The golden flakes of goodness are used in vegan dishes to give a creamy, cheesy taste and consistency. They can be cooked into sauce form or sprinkled on top of dishes as if it were Parmesan or other shredded cheese. Nutritional yeast is a great source of B12, one of the vitamins that play a role in our positivity, so sprinkle away.

5. Spinach

There’s a reason why Popeye loves spinach so much; it’s a nutritional powerhouse that is full of vitamin B6, folate, tyrosine, riboflavin, and zinc. The B vitamins play a large role in our happiness and positivity, and spinach is a great source of B6 (pyridoxine). You can get a nice serving of spinach in this Creamy Pumpkin and Spinach Lasagna.

Many researchers believe that imbalance in serotonin levels may affect our mood and can thus lead to depression. Beat the winter blues and become a more positive person by making the foods listed above a regular part of your diet.