As evidenced by the newly proposed dietary guidelines, science’s expert opinion regarding greater health and well-being is always changing — a natural result of continued research and increased resources. The same goes for weight loss, which can be especially frustrating for those who have followed the “tried-and-true” ways to lose weight to no avail.

In which case, we went back through some of the studies published in the last three years to pull out some of the newer, science-backed approaches to weight loss. Keep in mind, however, weight loss (as our overall health and well-being) is an individualized approach.

Then: Diet And Exercise Reduces Obesity

Now: Same, Plus Face-To-Face Counseling

In 2013, the American Heart Association and the American College of Cardiology updated the national guidelines on treating obesity for the first time since 1998. The two institutions analyzed 133 clinical research trials on how to best lose weight and achieve a healthy lifestyle, which they found starts by treating obesity as a disease. Though the American Medical Association classified the condition as such in July 2013, these guidelines were the first to recommend how to go about said treatment.

While good old fashioned diet and exercise remained the top ways obese people could lower their risk, the new guidelines added behavioral weight loss counseling to the mix. Counseling sessions can provide those struggling to lose weight healthy menus, as well as tools to set realistic fitness schedules and reverse otherwise unhealthy behaviors. Just last week, health coaching was found to reverse risk of full-blown diabetes in patients diagnosed with pre-diabetes.

Then: Eat Three Meals A Day

Now: Eat When You Are Hungry

The idea people should only eat three meals dates back to the New World; European settlers restricted their eating, whereas Native Americans ate whenever they wanted to. The thing is, appetite doesn’t keep a schedule. Anyone who’s found themselves pouring a bowl of cereal at 10 p.m. knows this all too well.

In the same vein, curbing hunger by starting each day with a well-balanced breakfast is no longer a sure thing; it’s complicated. And while fasting isn’t always viewed in a positive light, one of the newer recommendations for weight loss suggests it’s healthy when done intermittently. Not only does it promote loss, but animal studies have shown reducing calorie consumption 30 to 40 percent can increase life span by a third or more.

Then: Close Down The Gym

Now: Get Fit In As Little As 7 Minutes

The scientific seven-minute workout properly broke the Internet (sorry, Kim Kardashian) when it was published in the May-June 2013 issue of the American College of Sports Medicine’s Health & Fitness Journal. The workout involves 12 body weight exercises — New York Times's Gretchen Reynolds described it as a long run and visit to the weight room combined — and suggested high-intensity (and we’ll say it, discomforting) exercise boasts the same benefits of endurance training (at least 30 minutes) in much less time. So it’s no surprise body weight training claimed the No. 1 spot for 2015’s top fitness trends.

Granted, the effectiveness of the seven-minute workout has since been questioned, but not the weight training it’s modeled after. A study published in the journal Obesity found weight training is a more effective way to lose weight than running, cycling, or stair climbing. That's not to say those approaches don't work at all, but if you're short on time, high-intensity training is now a leading alternative.

Then: Overeating Causes Weight Gain

Now: Overeating Also Causes Changes In The Brain

Forbes reported after years of wondering why diet and exercise don’t help some people lose weight, a 2013 (and groundbreaking) study published in the British Journal of Nutrition in 2013 discovered years of overeating an American diet actually changes the brain. Read: a diet sourcing too many calories from fat and simple sugars.

“The evidence is quite convincing — eating fattening foods causes inflammatory cells to go into the hypothalamus,” Dr. Louis Aronne, director of the comprehensive weight-control program at New York-Presbyterian Hospital and Weill Cornell Medical Center, told the magazine. “This overloads the neurons and causes neurological damage.”

When the nerves are damaged, the hunger hormones leptin and ghrelin don’t function properly, which negatively impacts the body’s metabolism and ability to regulate weight. And while some damage may be permanent, Forbes reported, it’s possible to reverse it by cutting calories and fatty foods.

Then: Ingredient Exclusive

Now: Ingredient Inclusive

More like paleno: This year’s annual report of best diets from U.S. News & World Report bumped the popular caveman diet to last place. While diets, like the Mediterranean diet and Weight Watchers, were all winners, a 2014 study found it didn’t matter how slow or fast participants lost weight — it just mattered how they maintained their success over a long period of time.

A lot of the “best diets” focus on short-term solutions and certain ingredients. For example, Paleo goes heavy on the meat. Other diets will propose a certain amount of fat, protein, carbohydrates, sugar, and salt. But the truth is, it’s more important how people combine these ingredients together. And actually, a recent study found simply adding more fiber to an existing diet may be enough to kick-start weight loss.

"There is no ideal diet for weight loss, and there is no superiority between the many diets we looked at," Dr. Donna Ryan, who led the obesity guidelines overhaul, told USA Today. "We examined about 17 different weight-loss diets. There are many dietary paths to weight loss, as long as you are creating a calorie deficit."

Then: White-Yellow Fat Can Turn Into Brown Fat

Now: The Exact Protein That Stimulates This Change

As Medical Daily previously reported, there are two types of fat: white-yellow fat and brown fat. White-yellow fat basically makes up human bodies and “stores excess energy, builds around vital organs, and carries hormones such as estrogen, adrenaline, cortisol, and hunger-appetite regulators.” Brown fat, on the other hand, positively impacts metabolism and insulin resistance. It also uses up calories to keep the body warm.

Prior science shows white-yellow fat can be stimulated and turned into brown fat. Now, thanks to a study published in the journal Obesity, researchers have pinpointed the exact protein responsible for this change; it’s called transcription factor Zfp516. In addition to exercise, cold weather can stimulate white-yellow fat to turn into brown fat, which researchers believe has potential to spark new therapy for weight loss and diabetes.