Eating a well-balanced diet rich in fruits and vegetables can help protect against many chronic diseases. And yet, nearly 90% of Americans don't consume the recommended daily amount.

The rising costs of groceries due to inflation may be one reason. One solution: buying frozen, which is just as healthy and much cheaper than fresh.

In fact, studies have found that the nutritional value of many frozen foods (especially the amounts of vitamin A and C and folic acid) of some frozen fruits and vegetables is greater than fresh-stored options.

As a nutritionist, here's what I always buy from the frozen foods section:

1. Berries

Use it for: baked desserts, smoothies, yogurt toppings, breakfast bowls

Berries, such as blueberries, raspberries, strawberries and blackberries, are one of nature's best sources of antioxidants. Studies show that antioxidant levels in berries remain stable long after they're frozen.

Some of the best stores to find frozen berries at a bargain include Trader Joe's, Target, Whole Foods and Walmart. I've found that Costco can be more expensive per pound, but has organic frozen options at an excellent price point.

2. Chopped carrots

Use it for: soups, honey glazed and roasted, grain bowls, stir fried

Chopped frozen vegetables cut down on prep time, encouraging you to slip extra fiber and vitamins into your meals while also avoiding spoilage.

Carrots have a short shelf life, usually lasting only a few days in the refrigerator before starting to turn brown. Because they are frozen shortly after harvest, they can still maintain their fiber, vitamin A and beta-carotene nutrients.

3. Fish

Use it for: fish stew, baked, air fried, steamed and broiled dishes

Unlike fresh fish that travels for days before arriving in stores, the fish you find in the freezer section is frozen right after it's caught, keeping it at peak freshness. I buy frozen fish to get my intake of omega-3 fatty acids and vitamin D.

Try to look for fish that don't lose its texture or flavor when stored. Oily fish like yellowtail and tuna don't freeze well. I recommend going for frozen pacific cod, tilapia or pacific halibut instead.

4. Spinach

Use it for: smoothies, scrambled with eggs, dipping sauces, steamed

When fresh spinach sits during transportation over long distances or stays in your refrigerator for a week, its folate content drops so much that frozen spinach becomes the better source.

Even better, one cup of frozen spinach has more than four times the amount of nutrients, including iron, vitamin C and calcium, compared to a cup of fresh spinach.

5. Peas

Use it for: salads, caramelized in butter, grain bowls, steamed, stir fried veggies, dipping sauces

Buying fresh peas isn't always possible all year round. They can also be labor-intensive and time-consuming to shell and prep.

But frozen peas, which are rich in fiber and protein, can serve as a quick and easy addition to several dishes straight from the freezer.

6. Brown rice

Use it for: rice bowls, burritos, salad bowls, mixed with meat or assorted veggies

People often forget about grains in the freezer aisle. Brown rice is a superior source of fiber, B vitamins, and minerals like magnesium, which studies found can help reduce the risk of stroke and type 2 diabetes.

Even better, frozen brown rice takes between three to three minutes to cook instead of the 40 to 50 minutes for dried brown rice.

Mary Ellen Phipps is a registered dietitian, nutritionist and founder of Milk and Honey Nutrition. She is also the author of "The Easy Diabetes Desserts Cookbook: Blood Sugar-Friendly Versions of Your Favorite Treats," and a writer for HealthDay. Follow her on TikTok and Instagram.

Don't miss:

• A cardiologist shares the 5 foods she eats to lower cholesterol—and keep her ‘heart healthy’
• A longevity expert shares the diet, exercise and sleep rules he lives by for a longer, stronger life: These are ‘non-negotiable’
• A Harvard nutritionist shares the 6 best brain foods: ‘Most people aren’t eating enough of’ these

Sign up now: Get smarter about your money and career with our weekly newsletter