Identical twins try out 2 trendy diets for 30 days

— -- A pair of identical twins with the joint goal of losing weight tried out two different trendy diets for one month, and revealed their individual weight loss results live on "Good Morning America" today.

Lauren Holman and Leila Cruz, both 32, from Brooklyn, New York, tried the Whole30 and Counting Macros diets to see which one worked better for them. Both twins said they were hoping to shed the extra pounds they gained after having babies.

Prior to embarking on their diets, each woman met with Dr. Avigdor Dori, a clinical dietitian and exercise physiologist at Mount Sinai St. Luke's Hospital in New York City, to measure their body fat percentages and establish their goals. Dori suggested that women should have 30 percent body fat or less to be in good health.

Although the pair are genetically identical, and each strictly adhered to their diet plans, the 30-day challenge did not account for the lifestyle or environmental factors that could affect the twins' weight.

The Diets:

Twin 1: Lauren Holman

Starting Weight: 152.3 pounds

Starting Body Fat Percentage: 41.2 percent

Diet: Whole30

The Whole30 diet requires dieters to eat whole foods, meats, and vegetables, and bans sugar, alcohol, grains, legumes, soy and dairy for 30 days.

“What we do is we pull them out for 30 days and it's a pretty strict pull out,” Whole30 co-creator Melissa Hartwig, who coached Holman, told ABC News. “It’s like pushing the reset button with your health habits and your relationship with food.”

To stick to foods on the diet, Holman cooked everything herself.

Whole30 Diet Recipe: Cashew-crusted chicken and wilted kale salad

Whole30 Diet Recipe: Big turkey meatballs with roasted cherry tomatoes recipe

Holman's take on Whole30:

Holman told ABC News that her weight loss battle began shortly after she gave birth to her son three years ago.

"I was 115 pounds before I got pregnant and even after my pregnancy I haven’t gotten anywhere near my goal weight," she said.

Holman added that her weakness when it comes to maintaining diets has always been "snacking," saying that prior to starting, she felt "nervous" about doing the Whole30.

"There is not much snacking on Whole30," Holman said, adding that she was also apprehensive about giving up sugar.

Since completing one month of the Whole30 diet, Holman said she has lost 10 pounds, feels like she is no longer bloated and is sleeping better.

"It was also a great experience to do this with my boyfriend," Holman said. "Him and I both have struggled with weight loss since having our son so this was super fun to do together as a couple."

"The hardest thing about the diet was the first two weeks," she added. "I had to get used to reading every ingredient, and to my surprise everything has sugar."

"Another hard part about the diet was the money," she added. "It is very expensive to eat healthy."

Holman said the diet was "worth it in the end," telling ABC News that going forward she is "definitely going to keep up with the Whole30."

Weight Lost After 1 Month: 10.7 pounds

Body Fat Percentage After 1 Month: 5.1 percent

Twin 2: Leila Cruz

Starting Weight: 133.8

Starting Body Fat Percentage: 37.9 percent

Diet: Counting Macros

Counting macros is dubbed the new school approach to counting calories. To follow the diet, Cruz can eat whatever she wants, as long as it fits into her personalized pie graph of carbs, proteins and fats.

“There are three macro categories -- protein, carbs, and fats -- [and] having the correct amount of those three things is important,” SD-Evolution founder Alessandra Scutnik, who coached Cruz, explained. “We do recommend that 80 percent of your day is nutrient dense foods like fruits, veggies, complex carbs, lean meats and then that leaves 20 percent to be anything you want.”

Cruz said that 20 percent was ice cream for dessert.

For the rest of her diet, she weighed everything she ate and checked the macros to make sure everything stayed within her numerical range.

Cruz's take on Counting Macros:

"I haven’t been serious about losing weight mainly because I thought I couldn’t do it," Cruz told ABC News.

She said she "was able to eat what I want" with this diet.

"I ate all my favorite foods in moderation. Knowing how much protein, fat, and carbs I was allowed in each meal made it easier for me to pick meals for the day," she said. "As I continue to do the diet I definitely feel like I have more control over my day."

After completing the diet for a month, Cruz, like her sister, said she feels less bloated and noticed that she has been sleeping better.

Cruz added that one of the hardest parts of the plan was having to add certain foods to her diet in order to reach her protein goals.

"I ate protein bars and started drinking protein shakes," she said.

"Another struggle was weighing my food," Cruz added, saying as a teacher the logistics of weighing her food in her classroom were a bit difficult. "Also, if we ordered out I didn’t know the nutritional facts for certain foods."

She said she struggled slightly with having to log every single thing she ate each day.

Overall, however, Cruz said she feels "proud."

"I’m very proud of myself and how far I’ve come," she told ABC News. "It’s just the beginning of a steady healthy lifestyle."

Weight Lost After 1 Month: 6.7 pounds

Body Fat Percentage After 1 Month: 4.6 percent

Expert tips for mastering each diet:

Tips to Mastering the Whole30, from Whole30 co-founder Melissa Hartwig

1. Announce your commitment. Having accountability will keep you on track, and makes it easier for you to recruit friends and family for support along the way.

2. Recruit your support team. You’ll need motivation, encouragement, resources, and maybe some tough love along the way, so ask key players for exactly what you’ll need. Task your mom with daily encouragement, your best friend with a butt-kicking when you need it, and your Whole30-savvy co-worker with recipe inspiration if you get bored.

3. Clean out your pantry. If your Whole30 excitement is high you may be tempted to skip this step, thinking, “I don’t even want this stuff—no need to remove it!” But the future you will thank you for getting the chocolate out of easy reach when you’re cranky, tired and craving. Give it away, donate it to a local shelter, or box it up with lots of tape and stick it in the garage for a month.

4. Plan some meals. Having a robust plan for the first few days will help you alleviate stress and keep you on track when days run long.

5. Stock up on emergency food. During the Whole30, you can’t grab candy out of the vending machine if you’re in a pinch. Having plenty of “emergency food” on hand can help you work around getting stuck in traffic, travel days, and late meetings. Hard boil some eggs, prep a protein salad, stash some Whole30 Approved jerky or an RxBar in your desk at work, and roast a double-tray of veggies on Sunday night so you always have some on hand.

Tips to Mastering Counting your Macros from SD-Evolution founders Josh and Alessandra Scutnik:

1. Establish your baseline or “maintenance” calories and macros. If you are new to calorie counting and are unsure how much food you are consuming, the first step is to start tracking your current food intake using an app. It’s as simple as logging what you eat on a daily basis. At the same time, you want to be tracking your body weight to see if it is maintaining at this intake. We suggest tracking both your food and body weight for about two weeks. The reason why we suggest two weeks is that your bodyweight is going to fluctuate daily based on a number of factors including but not limited to sleep, stress, sodium levels, water levels and bowel movements. The most optimal way to get an accurate body weight average would be to weigh-in at least twice per week for two weeks, then take the average of those numbers. If your body weight is staying the same, we can assume these are your personal maintenance calories.

2. Purchase a food scale to measure your portions (this is more accurate than using measuring cups or spoons). This is important for at least the first few weeks to ensure you learn proper portion sizes, but using a food scale is not something you need to use as you become familiar with the foods you normally consume. The first few weeks are usually a big eye opener in regards to what your normal portion sizes look like!

3. Follow the 80/20 rule when choosing foods to eat. As long as you fill your day with 80 percent nutrient-dense choices, you can leave some wiggle room for foods that you enjoy and may not be as “healthy.”

4. Be consistent! The two most important factors with any diet are adherence and consistency. If you aren’t sticking to your plan and being consistent how will you know if it’s truly working for you?

5. Meal prep. Meal prep is an absolute game changer. By making your meals ahead of time, you are already prepared for your week. You don’t have to prep every meal, but having some go-to options handy will keep you in line with your goals and keep you on track!