Doctors Express Cherry Creek encourages you to keep your kids healthy at all times. The school year has begun and here is an article on how to keep your kids lunches filling and nutrious.

By Mitzi Dulan

Send your kids back to school with protein-packed school lunches. This is also a great opportunity to teach your kids why protein is important for them and explain which foods in their lunch are the best sources.

Protein intake is very important for kids to help keep their immune system strong and healthy. It also plays a key role for building and repairing muscles and helps them grow – kids really like this one! In addition, protein acts a structural component of cells and tissues including hair, nails and skin. Without protein, these cells and tissues are not able to function properly. Protein also provides energy in the form of calories. In other words, it will help them optimize their energy levels to play their favorite sports.

As you can see, protein has a lot of important roles in a kid's diet. Here are some of my favorite sources of protein for children's lunches:

1. Greek yogurt

I'm sure you have heard of Greek yogurt by now due to its incredible growth in popularity during the past few years. One of the reasons for that growth is because it is higher in protein and lower in sugar than most other yogurts. It is strained yogurt, which makes it richer in texture. In the grocery aisles today, you have many Greek yogurt options since so many companies have joined the market. You should read and compare the labels carefully.

Stonyfield offers an organic option while Chobani recently launched a new Flip line and also a Bite four-pack and sent samples to me. The Chobani Flip is brilliant! It includes a flip-up top with a little compartment of dry ingredients that are delicious mix-ins to that specific yogurt flavor. For example, Nutty for 'Nana has banana Greek yogurt with dark chocolate and honey-roasted, salted almonds and packs 13 grams of protein. This adds a great crunch that adults will enjoy as well!

2. Cheese

Cheese is another great way to boost protein intake, and most kids love it. It can also work well because there are so many great on-the-go cheese snacks made with 100 percent real milk that are available in grocery stores. Most provide about 5 to 6 grams of protein.

3. Nitrate-free deli sandwich meats

Deli meats such as ham or turkey are an easy way to boost protein intake. I choose the all-natural brands of deli meats. A few of my favorite nitrate-free options are Hormel Natural Choice and Applegate. They contain 10 to 12 grams of protein per 2 ounces of meat for only 50 calories.

4. Simply Snackin

I first tasted these dried meat snacks several months ago when the company sent me samples. I immediately loved them. They are absolutely delicious, with unique flavors and without nitrates. I gave them to my daughter's volleyball team, which also loved them. With only 60 calories and 8 grams per serving, these snacks are a perfect addition to your kid's lunch. One of my kid's favorite flavors is the Beef Sirloin with Apples & Cherries. You can buy them online at: SimplySnackin.com

5. Low-fat cottage cheese

This is a protein gem for kids, providing 14 grams of protein in only half a cup. A few great mix-ins for cottage cheese can include pistachios, almonds and dried cherries.

6. Hard-boiled egg

These are very popular at my house, and my kids will even make them on their own (with an adult in the house, of course). One hard-boiled egg provides 6 grams of protein.

7. Low-fat organic milk

Low-fat milk is a great source of protein, providing about 9 grams in 1 cup and many other nutrients that are important for kids, such as vitamin D, riboflavin and calcium. I buy organic milk for my family and recommend my clients do the same.

For non-animal sources of protein for lunch, I recommend beans, lentils, quinoa and freekah. You can make delicious salads with all of these protein options. I have several on my Pinterest boards.

Please share your favorite way to boost the protein intake in your kid's lunch!

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