The new year is fast approaching, which means it's time to make your list of resolutions for 2018. But, we all know how that goes. Good intentions for a better lifestyle, repaying debts or learning a new hobby can quickly fade because of dwindling motivation, an already full schedule or frustration with results not happening fast enough. For me, the new year is a chance to ditch old habits, like drinking a soda with breakfast, and create a new, healthier eating routine. However, the fact that the majority of people who set goals for the new year give up on their resolutions by February didn't instill me with confidence. "Being prepared is 50 percent of the equation," said Amy Shapiro, a registered dietitian and nutritionist and founder and director of Real Nutrition NYC. Was there a way to set a solid foundation for healthier eating that provided me structure and flexibility?

Recipe for Purple Carrot meal Kate Sprague | CNBC

Enter meal kits — and a structured meal plan that arrives at your door. "[Meal kits] are great," Shapiro told CNBC. "It gives you all the ingredients in the right proportions, tells you exactly what to do and gives you the tools so you don't feel overwhelmed."

There's no one diet that everyone should stick to, said Carol Johnston, professor and associate director at Arizona State University's School of Nutrition and Health Promotion. The trick is finding what works for you and your body, she said. So I selected four kits that billed themselves as nutritious and catered toward different diets, like vegetarian, paleo or gluten-free.

Sun Basket

Diet: Paleo

Price: $11.99 per serving

Shipping cost: $6.99 I was pretty unfamiliar with the paleo diet before testing out several meals from Sun Basket. Basically, you only use ingredients that would have been accessible to cavemen 10,000 years ago. That meant saying goodbye to items like dairy, grains, processed sugars and starches. Sun Basket offers a number of meals that cater to this dietary regimen, as well as gluten-free and vegetarian. I had assumed that paleo meals would be bland and basic but was pleasantly surprised to prepare a meal that was easy to make and delicious.

Cutting beets for Sun Basket meal Kate Sprague | CNBC

One of the recipes provided by Sun Basket was a pan-seared chicken breast on top of a smear of parsley-pecan pesto with roasted beets and oranges. I'm no master chef, but this was the best chicken I have ever made. It was juicy and tender.

Roasting the chicken breasts, beets and oranges from SunBasket Sarah Whitten | CNBC

While I probably could have chopped the beets a little thinner, they were earthy and tangy from the orange and rosemary, and I couldn't stop eating them. As for the kale, I've never been a huge fan of this leafy vegetable. I've always found it really bitter and hard to chew. However, wilting it and adding vinegar, as I was instructed to do in the recipe, gave it a really nice flavor and the texture was softer and easier to eat.

Chicken breasts and parsley-pecan pesto with roasted beets and oranges from SunBasket Sarah Whitten | CNBC

Purple Carrot

Diet: Plant-based

Price: $72 per week

Shipping cost: free It can not be overstated how much I enjoy a good steak or cheeseburger. So, a vegetarian diet has never really been an option for me. However, after eating this recipe from Purple Carrot, I may consider adding more plant-based meals to my eating regimen. One of the meals included in my Purple Carrot box was za'atar sweet potato noodles with crispy chickpeas and broccolini.

Chopping broccolini for meal from Purple Carrot Kate Sprague | CNBC

The roasted chickpeas were the star of the dish. The za'atar seasoning, which is a mixture of sumac, thyme, oregano and sesame seeds, paired wonderfully with the nuttiness of the chickpeas. The roasted chickpeas alone are something I would make again as a snack or for part of another meal.

Za'atar Sweet Potato Noodles with Crispy Chickpeas and Broccolini from Purple Carrot Sarah Whitten | CNBC

The sweet potato noodles were easier to cook than I expected and were made in the same way you make pasta. The sweet potato remained some-what crunchy, which was fine for me, but I'm not sure what texture the noodles were supposed to have been. Regardless, I appreciated that the sweet potato was already cut into spirals. Otherwise, I have no idea how I would have accomplished that. The vinaigrette, made with garlic, lemon and champagne vinegar, paired nicely with the za'atar seasoning and added a little more depth to the flavor of the broccolini. I'm not sure I would make this exact recipe again, but I would definitely make pieces of it. I felt satisfied after eating this dish and didn't feel the need to add anything else to the plate.

GreenBlender

Diet: Breakfast smoothies

Price: $49 per week

Shipping cost: free Rule #1: Buy a blender. Food processors are very handy in the kitchen. But making smoothies isn't one of their best uses. I learned that the hard way. GreenBlender is a delivery service that provides you with a box of preportioned ingredients so you can make nutritious smoothies at home. Select five recipes from a list of eight each week and you'll receive enough ingredients to make two of each recipe.

Ingredients for Orange Cranberry Calm smoothie from GreenBlender Sarah Whitten | CNBC

The smoothie I tested was the Orange Cranberry Calm. This blend is made from whole cranberries, an orange, a pear, ginger and pumpkin seeds. The company provides everything you need except for the ice and water you add during the blending. All I had to do was chop up the pear and the orange and blend it with ice and water. It took a little over five minutes and I was done. Now, part of my trouble was that I was not equipped with the proper tools, so my smoothie didn't exactly blend. The texture was incredibly chunky and unappetizing.

Orange Cranberry Calm smoothie from GreenBlender Kate Sprague | CNBC

Still, the smoothie was very tasty. The cranberries and orange were tart and crisp, the pumpkin seeks added a nice nuttiness and the ginger gave it a little kick. What was really nice about this kit was that everything was preportioned. I didn't need to buy a large bag of pumpkin seeds or a whole piece of ginger. Plus, all of the fruit was fresh and ripe. While I could purchase all the ingredients at a grocery store, I really appreciated that everything was in little kits with everything I needed inside separated by recipe. I think it is worth the $49 expense to have everything arrive at my door.

TB12

Diet: High protein and gluten-free

Price: $78 per week

Shipping cost: free New England Patriots quarterback Tom Brady is known for his strict diet. The five-time Super Bowl winner doesn't eat dairy, caffeine, white sugar, white flour, MSG … and the list goes on. He also avoids nightshades (tomatoes, peppers, eggplant, etc.), limiting consumption to a few times a month. So, that cuts out a lot of things that are in my diet. Brady's personal chef has said that about 80 percent of his food is vegetables, the rest is lean meats. However, since the kit is sold in partnership with Purple Carrot, it does not contain meat. The kit that I received came with three meals, but I decided to try my hand at the recipe for maple-glazed acorn squash with creamed spinach and cannellini beans.

Maple-Glazed Acorn Squash with Creamed Spinach and Cannellini Beans from TB12 Sarah Whitten | CNBC

I really appreciated that the company precut the acorn squash into rings, it saved me time and the hassle — danger — of trying to cut through the squash myself. The creamed spinach, which utilized coconut milk instead of milk, was easy to create using the recipe card. Although, ultimately, I felt that the coconut flavor overpowered the dish, which also contained spinach, cannellini beans and nutritional yeast. I wasn't a huge fan of the creamed spinach, so I was left with two small slivers of acorn squash, which were delicious but hardly filling, which is something I've noted about this meal kit before. Since the recipe was easy to follow and would be simple to shop for, I would probably make the acorn squash again but substitute something else for the creamed spinach and add some chicken or pork.

Final thoughts