Diet trends for 2019: What to try, what to skip

Losing weight and getting healthy is always a top New Year's resolution. If you're hoping to revamp your diet in 2019, there's certainly a long list of eating plans to choose from, and like every year, trendsetters are pushing a number of strategies that promise big results but don't always deliver.

From the popular high-fat, low-carbohydrate ketogenic diet to the mindful eating style of listening to your body's hunger cues, we round up some expert advice on which diet plans may work best for you in the new year — and which ones to leave behind.

Ketogenic diet

The ketogenic or keto diet was big in 2018 and experts predict the trend will continue through the new year.

The diet involves drastically reducing your intake of carbohydrates and replacing them with fats, forcing the body into a state of ketosis — when you burn fat instead of carbohydrates for energy.

The notoriously restrictive diet calls for its followers not only to reduce intake of unhealthy carbs like sugar but also those that are normally considered healthy, like most fruits and certain vegetables.

While research shows that a ketogenic diet can help control seizures in children with epilepsy and may be beneficial to people with type 2 diabetes, dietitians generally do not recommend it for weight loss.

"It's not typically something that can be sustainable over time," Kelly Hogan, a registered dietitian and clinical nutrition and wellness manager at the Mount Sinai Dubin Breast Center, told CBS News. "Any diet that's going to set forth rules and severely restrict food intake is going to create fear around certain foods. In this case that food category is carbohydrates. Any type of diet like this gives me pause because it can promote disordered eating and an unhealthy relationship with food."

Paleo + vegan = "pegan" diet

Mark Hyman, M.D., director of the Cleveland Clinic Center for Functional Medicine and author of the book, "FOOD: What the Heck Should I Eat?" introduced the world to the "pegan diet" a few years ago and it's been growing in popularity.

This diet plan combines aspects of a vegan diet, which avoids all animal products, and the Paleo diet, which focuses on consuming the types of foods our ancient ancestors supposedly ate during the Paleolithic era.

"It's really simple," Hyman told CBS News in an interview earlier this year. "Eat foods low in sugar and starch. Eat lots of plant foods. If you're going to eat animal foods, eat sustainably grown or harvested foods. Have foods that have lots of good fat, like nuts and seeds, olive oil, avocados."

A good place to start, he says, is to read the ingredient lists on the foods in your cupboard.

"If you have an ingredient you would cook with, like salt and pepper, great," Hyman said. "If it's butylated hydroxytoluene, you're probably not going to have that in your cupboard and sprinkle it on your veggies."

However, Kelly Hogan notes for some people, the diet may not be sustainable in the long-term.

"I think you really have to think about why you're doing it in the first place," she said. "If you're following a vegan diet because you are passionate about animal rights, that's great. But if you're following a vegan or Paleo diet solely for weight loss or you think it will change your body in a way that society deems more 'acceptable,' then we have to think twice about something like that because these diets are so restrictive."

Intermittent fasting

Intermittent fasting is another trend that has been gaining more traction in recent years.

This diet plan isn't so much focused on what you eat but when. For two non-consecutive "fast" days each week, intermittent fasters abstain from eating except for one small meal of just 400 to 500 calories for women and 500 to 600 calories for men. For the remaining five "feed" days, you can eat whatever you want.

Research shows intermittent fasting can lead to weight loss, with one study showing alternate-day dieters can lose an average of 10 to 30 pounds in about eight weeks. Other studies found this type of diet, along with regular exercise, may be beneficial for lowering LDL or "bad" cholesterol levels and blood pressure.

However, abstaining from food can be difficult for obvious reasons and some people may be better suited for this type of diet than others.

"I may recommend intermittent fasting as a strategy for weight loss patients who are focused, determined, and motivated in improving their health goals," Nancy Z. Farrell, a registered dietitian nutritionist and spokesperson for the Academy of Nutrition and Dietetics, told CBS news.

Hogan also worries that this style of eating could lead some to disordered eating habits.

"Some people swear by intermittent fasting and it works for them and that's great. I would never tell them to stop, but it's not something I would ever outright recommend to a patient because it's promoting a weird relationship with food where you're not allowed to eat at certain times and have to eat during others and that's not a road I would ever want anyone to go down," she said.

Eat more plants

"One trend that I love that we've been seeing and that I think will continue through next year is people eating more plants," Hogan said.

According to the USDA, most adults should be getting 3 to 5 servings of vegetables and 2 to 4 servings of fruit per day. Put more simply, half your plate should be filled with produce.

Incorporating more plants in your diet doesn't require any drastic changes, Hogan says.

"It's all about replacing an animal product here or there with a plant product or really focusing on including plants in every meal. Maybe try a meatless Monday to designate a day to experimenting with new plant-based recipes so you can learn what you like and different combinations of food that you might not have tried before."

Practice mindful eating

Mindful eating is an emerging diet trend that both Hogan and Farrell hope is here to stay. The concept is simple: You listen to your body and eat when you're hungry and stop when you're full.

"This gets away from black-and-white thinking when it comes to food, and putting all food on a neutral playing field," Hogan said. "For example, kids, before they come entrenched in diet culture, they very simply eat when they're hungry and stop when they're full and have what they feel like. That's what intuitive, or mindful, eating is bringing us back to."

Hogan says this style of eating can foster a more positive relationship with food, which can greatly increase quality of life.

Farrell notes mindful eating also encourages people to slow down and actually enjoy their food.

"Mindful eating helps to increase our awareness of our thoughts, feelings and sensations rather than simply putting more food into our mouths," she said. "We are such a fast-paced world and we eat on the run. School lunches are timed, we eat while driving, we eat while working at our desk. Mindful eating helps us to focus on the nurturing aspect of nutritionally healing our body through total wellness."