In Part 1 of our week-long series on diet and fitness trends, we take a closer look at diet plans and supplements that have become more popular in recent years.

In Part 1 of a series we examine the latest diet trends. (s1rena, ThinkStock)

Once popular, protein-heavy diets such as Atkins and South Beach are becoming less prominent, while those promoting "clean eating" and liquids such as protein shakes, are in.

In addition, exercise programs like P90 and the 21-day Fix are among more than 25 in-home workouts driving the popularity of the Beach Body Program that pairs fitness DVD's with nutrition plans, guided by the help of coaches such as Karen Moeller of Toms River.

"They come with recipes and you can also supplement with the Shakeology shake, which is part of Beach Body as well. It's like a meal replacement. It has vitamins and all the minerals, super foods, that your body needs," Moeller said.

Moeller has been selling Beach Body programs for about a year and doesn't feel like this trend will fade any time soon because it continues to grow and market new workouts.

Moeller said she coaches hundreds of clients obtained mainly through social media and word-of-mouth. She uses Facebook to hold private challenge groups, and you may have seen other Beach Body posts with "before" and "after" results.

"The thing with Beach Body, it's fitness, plus nutrition, plus the support from a coach is what's going to give you success. The combination is what people are connecting to," Moeller said.

The cost of the Beach Body program ranges from about $59 to $205 with shakes, according to Moeller.

Shannon Mulrooney of Brick is finding success so far with the 21-day Fix and Shakeology combination.

"I lost 13 pounds and 16 inches in 6 weeks," she said. "It's fitness and diet, and more about portion control. You get different color containers and a certain amount of food that you are allowed to eat each day, and the Shakeology replaces one meal a day for me."

Another eating plan that's also gained popularity is the Paleo Diet. The plan is based on the Paleolithic age of the caveman. You can eat plenty of meat, fish, poultry, vegetables and fruit, but you are not allowed to have any refined sugars of any kind, no dairy products, no grains and no legumes.

Similar to other high protein diets, most of the weight is lost up front, according to consumerscompare.org. There aren't many studies on the Paleo Diet, because it is still somewhat new. One study showed moderate weight loss in the first three weeks, or about five pounds, with no weight loss and/or weight gain after eight weeks. In addition, like most other diets, exercise is recommended with the Paleo Diet. Consumerscompare.org concluded the Paleo Diet can be difficult to follow, requires a lot of willpower and can be pricey.

If eating like a caveman doesn't sound appetizing, there's the Mediterranean diet plan, based on eating lots of fruits and vegetables, beans and nuts, healthy grains, fish, olive oil, small amounts of meat and dairy, and red wine combined with daily exercise. Webmd.com gives the Mediterranean plan kudos for hearth health and according to the website, studies suggest it can make you less likely to get heart disease, lower your blood pressure and cholesterol, and may help you avoid certain cancers and chronic diseases. In addition, the Mediterranean diet has few limitations and allows plenty of variety and experimentation.

Some who have tried fad diets and failed are trying something edgier - HCG, or human chorionic gonadotropin hormone injections.

"It is urine from a pregnant woman, which is tested in a lab, in the pharmacy, and that's what we use," said Jill Houston, a Clinical HCG Specialist at Ocean Health & Weight Loss in Toms River.

"HCG is FDA-approved to make babies at a stronger percentage. So one million times stronger it makes babies, but at a minimal amount, it takes away your appetite, which is off-label, similar to other drugs, which are used off label for other things, and this happens to be off-label for weight loss," Houston said.

HCG has been around since 1954 and its widespread use in Europe is gaining more popularity in the United States, according to Houston.

"It just seems to take away your appetite. It burns at least 2,000 calories a day, and it just melts away the inches," she said.

Dr. Sheri Emma, MD, owner of Dr. Emma's Weight Loss in Colts Neck, developed a protocol for administering HCG, and gained national attention after appearing on the "Dr. Oz" show in 2011 to discuss her findings.

"It's a pro-hormone, or hormone booster, and most of us are a little hormone deficient. So when you put this into the system, and you start making hormones a little more efficiently, guess what happens to the metabolism? Everything starts to pick up and function better."

Dr. Emma added that because HCG is so dose-dependent and involves a specific science, it should be administered by someone well-versed in it.

HCG is effective when combined with a low calorie diet, and those who try this type of weight loss regimen are placed on maintenance programs, according to Dr. Emma and Houston. Some of those who shared their experience with HCG agree, you still have to change your way of eating and mindset to eating healthier.

Christina Gaetano of Pine Beach, one of Houston's clients, tried fad diets and even went on the once popular Fen-Phen fat burner pill for two weeks before it was banned by the FDA in 1997. Dieting when she was younger was about being thinner, but losing weight as she got older became more serious due to health concerns related to high cholesterol and blood pressure. She lost 100 pounds in less than one year with HCG.

"It's not something that I'm measuring and that I'm keeping close tabs on. I'm really trying to think of it as a way of life and not a time-sensitive diet," Gaetano said.

Darlene Bosco of Freehold, a patient of Dr. Emma's, lost more than 40 pounds in six months, after also trying various other weight loss programs and going to the gym.

"I tried many methods, they weren't working," she said.

The side effects of HCG appear to be very minimal, other than if use of the hormone is stopped abruptly, it can cause extreme fatigue or temporary hair loss. Those with a cancer history or a low immune system also are advised against using HCG. Depending on which HCG clinic you go to, package prices can vary from a couple of hundred dollars to as much as $1,000.

Although Houston and Dr. Emma tout their HCG programs as having a high success rate, both agree, keeping the weight off is still up to the individual.

"It's like any diet. If they don't follow it, it doesn't work. People have to really step up for themselves and take responsibility. That's part of a new life style," Houston said.

Dr. Emma said patients, not the supplement, drive the progress.

"It's not a magic shot. There is no magic pill. If you can drive the weight loss, it's very empowering and then you can keep it off, because you'll know what to do," Emma said.

Editor's note: This article  is not meant to promote or endorse any specific diet plan. As with any diet or exercise routine, you should first consult your physician.