Weight loss ultimately comes back to the concept of calories in, calories out: Eat less than you burn and you’ll lose weight. And while it’s possible to lose water weight quickly on a low-carb diet, I certainly wouldn’t advocate for it. The diet itself can trick you into thinking that this eating style is working — when really, you might gain back what you lost as soon as you eat carbs again. That can feel incredibly dispiriting if you want results that last longer than a week.
“Intermittent fasting can be really challenging if you have an ever-changing schedule,” adds Hultin. “If you're traveling and crossing time zones, it could be very difficult to follow. It might be best for people with more stability in their lives.” Intermittent fasting isn’t safe for people with type 2 diabetes, children, pregnant or lactating women, or anyone with a history of an eating disorder.
"Research continues to support the role of a high-protein diet and weight loss, however, we don't want to reach those protein needs exclusively with animal proteins. Plant proteins found in beans not only help us feel full and stabilize blood sugar but beans are associated with longevity. Who cares about being skinny if you die young?" —Jennifer McDaniel, MS, RDN, CSSD, LD, food and nutrition expert
The easier it is to seamlessly fit a diet plan into your life without major lifestyle changes, the better. After all, by focusing on holistic long-term results rather than trendy short-term solutions, sustainability becomes the number one enemy of the feared “yo-yo” effect. During our investigative process, we asked ourselves: What makes a diet plan sustainable? After long hours of research, we decided that the following factors can determine a plan’s sustainability, and thus its odds of success: 
"Your body begins to work differently. This study proves that small amounts of nourishment throughout the day are better than the same amount of food concentrated in three big sittings. If we feed the body at regular intervals we send a signal to the body that it doesn't have to store calories. Conversely, when we skip meals we send just the opposite signal for the body to store calories, creating a negative effect on the metabolism." — Dr. Wayne Scott Andersen, co-founder and Medical Director at Take Shape For Life
A big part of weight loss is simply being aware of the decisions you’re making. For example, when out at happy hour with friends, you may lose track of how much you're eating or drinking. But if you take a split second to step back and become aware of that fact, you’re more able to course correct. “The awareness and then planning for what else I can be doing, that might give me the same benefit of eating comfort foods,” says Gagliardi.
There’s a large spectrum of where people can fall on a vegetarian diet: For example, vegans consume no animal products, whereas ovo-lacto vegetarians eat both dairy and eggs. The eating style may help with weight loss, suggests a review published in August 2017 in Nutrients, but some vegans and vegetarians may become deficient in specific nutrients, such as calcium, iron, zinc, and vitamin B12, according to an article published in December 2017 in Nutrition, Metabolism and Cardiovascular Diseases. (23,24)
It seems counterintuitive to drink lots of water when you’re looking to lose weight fast—especially water weight—but staying hydrated is one of the most important steps you can take to lose weight. People often mistake thirst for hunger, so staying hydrated allows you to be more in touch with the times when you are actually hungry, rather than just thirsty. Plus, a lot of good things happen to your body when you drink enough fluids.
The "all meat all the time" low-carb approach or strict veganism can be great options for people who thrive on clear diet rules (and those two are actually the most popular diets out there) but these extremes are not for everyone. If you prefer more of a moderate approach, the Flexitarian diet is the clear winner. The "flexible vegetarian" mindset allows you a healthy balance of plant-based foods, responsibly sourced meats, and quality fats. The best part? It's not super restrictive, so you have plenty of nutritious food options. (Start here: How to Adopt a Flexitarian Diet)
"Use a VersaClimber or take a VersaClimber class. These machines are still not that common, but in my opinion they are far more effective for weight loss than other forms of cardio. They require you to use a large portion of your muscles and it's functionally better for you than other forms of cardio like spinning. Everyone is talking about Rise Nation in LA at the moment as they are the first dedicated VersaClimbing studio. There's no harder cardio workout I have tried. To lose fat you have to put in the work. — Dan Roberts, celebrity trainer and creator of Methodology X
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