At the start of every year, millions of people the world over make the same bold proclamation: “As my New Year’s resolution, I promise to lose weight this year.” The sentiment behind this resolution is admirable. And if people want to lose weight and be healthy, that is a good thing. However, the mental (and more importantly, dietary) fortitude needed to turn this resolution into reality frequently has these same people walking back their promises to themselves by around mid-February.

Here’s the thing: losing weight and staying healthy shouldn’t be difficult. It just takes some planning and goal-setting, and some personal discipline as well.

Be SMART About Goals

Accomplishing anything starts with the right mindset, and to put yourself in that mindset, establish a goal that you think is realistic. For annual goal-setting activities, management professionals frequently use the acronym SMART to describe the goals they set: Specific, Measureable, Achievable, Relevant, and Timebound.

You can use the same model to give more structure to your weight loss goal. For example, instead of saying, “I’m going to lose weight this year,” which is an abstract way of thinking about it, you can instead say, “My goal is to lose five pounds by the end of February.” This gives your commitment more shape and makes what you’re shooting for more tangible.

Portion Size Versus Serving Size

As a child, you may have been told to always finish everything on your plate to keep food from going to waste. This practice may have contributed to the current rate of obesity in the United States, where an estimated 39.8% of adults were considered obese in 2015-2016, according to the Centers for Disease Control.

Many restaurants and fast food chains have used this belief against their customers, presenting them with ever-increasing portions of food. Customers feel compelled to finish what they’ve ordered and ended up overeating as a result. Multiply this by around 93 million people in the US, and you have an obesity epidemic on your hands.

So the next time you eat out, consider your portion size instead of your serving size. Whether you plan to eat organic food, keto-friendly snack bars, or simply remove sweet and salty food, you need to eat a reasonable amount, and feel satisfied with your meal. You can put leftovers in a doggy bag and take them home for your next meal, to prevent food waste. Better still, do this at the start of the meal: when your food arrives, set aside a reasonable portion for yourself, and have the rest wrapped up to go. This will help you develop the portion discipline necessary to manage your weight well.

Health Is a System

Your body is a complex machine made of many moving parts, each of which requires stores of energy to function. Energy typically comes from food and the nutrients they contain: fats, carbohydrates, vitamins, and so forth.

But so much misinformation over the years has made it challenging to choose what to believe. Should you have a low-fat, high-carb diet, or the other way around?

Your body is a system, and merely removing one in favor of another is likely to cause some negative effects. The truth is humans need a balanced blend of many different nutrients to lose weight, be healthy, and operate optimally. In general, a diet of complex carbohydrates from beans and vegetables, along with good fats from nuts or oily fish, and an occasional source of trans fat like a slice of pizza or some fries, is perfectly fine. For snacks, consider cutting back on the simple carbs of cakes and processed foods and try some keto-friendly snack bars instead.