It’s 2 p.m. and your energy is flagging. Before you power through that candy bar or load up on caffeine, reach for a snack that will boost your brainpower instead. 

“The snacks you grab have an immediate effect on how you feel,” says Nikki Drummond, a clinical nutritionist with NeuroFit Nutrition, who helps clients balance their body chemistry with the foods they eat to maximize health and energy. Food like fruits, vegetables, nuts, low-fat dairy products, whole grains, and legumes are satisfying and packed with the nutrients, fiber, and protein your body needs. They also guard against the sugar highs and lows that candy bars or other sugary snacks will give you. 

However, there are certain foods in these categories that are particularly rich in healthful components like omega-3 fatty acids, B vitamins, and antioxidants, which are known to support brain health and often referred to as superfoods. Here are the top five power snacks to help boost your energy and brainpower: 

1. Go Green

Leafy greens such as kale, spinach, collards, and broccoli are rich in brain-healthy nutrients like vitamin K, lutein, folate, and beta carotene. Research suggests these plant-based foods may help slow cognitive decline. In fact, one study showed that eating up to seven servings of fruits and vegetables a day left people feeling happier, more creative and engaged, according to a study. Snack on broccoli with hummus, a small side salad, or a green juice packed with kale and spinach. 

2. Get a Berry Boost

Strawberries, raspberries, or blueberries are packed with power and make an easy, on-the-go snack. They contain flavonoids, the natural plant pigments that give berries their brilliant hues, which help improve memory, research shows. In a 2012 study published in Annals of Neurology, researchers at Harvard’s Brigham and Women’s Hospital found that women who consumed two or more servings of strawberries and blueberries each week delayed memory decline by up to two-and-a-half years.

3. Snack on Walnuts

Eat a handful blend into a smoothie or add to a salad for a mental boost. Filled with healthy omega-3s and other nutrients thought to protect against Alzheimer’s and lower blood pressure, walnuts also help people perform better on cognitive tasks, according to research from UCLA. Walnuts may enhance memory, processing ability, and mental agility by reducing cellular inflammation and adding antioxidants that protect against stress.

4. Stay Hydrated with Water

No need for an expensive energy drink. Instead, make sure you are sipping water throughout the day. Afternoon fatigue can be a sign that you are edging near dehydration. The body needs water to move energy-boosting nutrients through, and if you fall behind on water consumption you and your cells will feel sluggish. Even mild dehydration limits our ability to stay focused on our work, according to researchers. 

How much do you need? It depends on several factors, including your health, how active you are, and where you live. But the National Academies of Sciences, Engineering, and Medicine determined that adequate daily fluid intake is about 15.5 cups (3.7 liters) of fluids for men, and about 11.5 cups (2.7 liters) of fluids a day for women. These recommendations cover fluids from water, other beverages, and food. About 20 percent of daily fluid intake usually comes from food and the rest from drinks.

5. Pack Portable Proteins

Greek yogurt, string cheese, chickpeas, edamame, peanut butter (good on an apple wedge or whole-grain bread for added energy), and other lean proteins are essential to building and repairing muscles and tissues and supporting brain health. One UCLA study even found that the probiotics in yogurt can support better decision making and help ease stress.

The foods you eat have a significant influence on motivation, focus, and productivity. By snacking smarter, you’ll not only fight the midday slump, but you’ll also power your health and well-being.