The Basics of Losing Weight

Once you understand how your body holds onto weight, you can craft an effective plan for letting those extra pounds go.

Medically reviewed in June 2021

If you struggle with your weight, you know it can be a frustrating, isolating experience. But many Americans are in the same boat. More than 73 percent of adults in the United States are either overweight or obese, according to the Centers for Disease Control and Prevention (CDC).

While working to maintain a healthy weight takes effort, both physically and mentally, the rewards are great. Simply put, staying at a healthy weight is a crucial part of maintaining an overall healthy lifestyle.

When you keep your body weight in check, you may decrease your chances of developing heart disease, high blood pressure, diabetes, stroke, osteoarthritis, sleep apnea and certain cancers. Controlling the numbers on your scale can also go a long way toward easing aches and pains associated with strained or damaged joints, bones and muscles.

Getting from where you are to where you want to be can be a challenge. Here’s what you need to know about how weight gain happens and how you can take simple, effective steps today to start losing weight.

Why does your body hang on to pounds?
In a nutshell, your metabolism is the process by which your body burns the calories in the food you eat to generate energy for everyday living. Some people start with a higher metabolism, which means they naturally burn more calories, while folks with a slower metabolism burn fewer calories with the same amount of food.

For most people, metabolism generally tends to slow down as they age. This means that if you continue eating the same amounts and types of food you did when you were younger, but you don’t increase your level of physical activity, you are likely to gain weight.

When your metabolism slows, your body composition, or the balance of fat and muscle in your body, may also change. The amount of muscle you have may decrease and fat may increase. With nature working against you in this way, trying to keep weight off after you’ve lost pounds—or even just trying to maintain your current weight—may take effort. The key is to be mindful of your calorie intake and activity levels.

If you need to lose weight, you’ll likely need to reduce the number of calories you eat by 500 to 750 calories each day. If you are at your ideal weight and your weight stays the same for a few months, chances are you are eating about the right amount. Your healthcare provider (HCP) can help you determine a calorie level that makes sense for you.

Is it helpful to know your BMI?
BMI (or body mass index) is a commonly-used measure that estimates your level of body fatness. It’s calculated by dividing your weight in kilograms by the square of your height in meters. If the resulting number is high, it suggests high body fatness, while a low BMI indicates low body fatness. You can find calculators online that allow you to input your height and weight to determine your BMI.

The categories associated with BMI are:

  • Below 18.5: Underweight
  • 18.5-24.9: Normal or healthy weight
  • 25.0-29.9: Overweight
  • 30.0 and above: Obese

Note that these ranges are slightly different for Asian and Asian American adults.

It’s important to recognize that BMI is not the only indicator of a person’s overall health. BMI can be a helpful screening tool, but it does not diagnose the actual body composition or health of an individual. It’s typically a starting point that an HCP uses to make a fuller assessment of a person’s health. Other tools that can help gauge your overall fitness include skinfold thickness measurements along with evaluations of diet, physical activity and family history.

Getting to a healthy weight
Once your HCP helps you determine a healthy weight for you, you’ll need to develop a plan to get there. While there are a number of factors that can affect your weight that can’t be changed—such as your genetics, age or sex—there are plenty of things that are within your control. Here are some concrete steps you can take to help you lose weight or maintain a healthy weight.

Review your eating plan. Key components of a healthy diet include:

  • Whole fruits and vegetables, especially colorful ones, including leafy greens
  • Grains, with at least half of your intake coming from 100 percent whole grains
  • Fat-free or low-fat dairy products  
  • Lean proteins, such as poultry, fish, eggs and plant-based sources such as beans and nuts
  • Healthy oils that come from seafood, vegetables and nuts

Meanwhile, a healthy eating plan should limit these foods:

  • Added sugars in foods and beverages
  • Saturated fat, which comes mostly from animal products and butter, but also from some plant-based sources like palm and coconut oils. Limit saturated fat to less than 10 percent of the total calories you eat each day.
  • Sodium, often hidden in many packaged foods. Ideally, you should get less than 2,300 milligrams a day.
  • Alcohol intake should top out at no more than two drinks a day for men and one drink a day for women. Less is better, and if you don’t already drink alcoholic beverages, don’t start.

Regardless of how your diet is composed, practicing smart portion control is essential to staying within your calorie limits.

Add physical activity. Try to exercise every day. For substantial health benefits, adults should get between 150 minutes (2 hours and 30 minutes) and 300 minutes (5 hours) of moderate-intensity exercise each week. Think brisk walking or working in your yard.

If you’re able to kick your workout up a notch, shoot for 75 minutes (1 hour and 15 minutes) to 150 minutes of vigorous-intensity aerobic activity each week. That might be running, swimming laps or taking an interval training class. You can also mix and match your workouts, going moderate on some days and more vigorous on others.

When it comes to exercise, you can reap more benefits, including weight loss, by logging more than the recommended amounts. Just be sure to check with your HCP before you start a new exercise program.

All adults are also advised to include some form of muscle-strengthening exercise twice a week. These moves should hit your major muscle groups. Think lifting weights or doing body-weight or weight-free moves like pushups, squats or water aerobics.

Get enough sleep. If you don’t rest enough on a regular basis, you may have a harder time maintaining or losing weight. Sleep deprivation can increase your appetite for high-calorie, high-carbohydrate foods, which can lead to weight gain. Stress hormones that encourage the body to hold onto fat can also be affected by getting too little sleep.

Start small for big benefits
Setting a goal to lose weight or to manage your current weight can seem daunting. Experts say it often helps to start by making small changes in your routine. These habits can eventually become second nature.

Start with little tweaks that can become a part of life without your having to think much about them. These include:

  • Be more active in everyday routines. Park at the back of the supermarket parking lot so you walk more steps. March in place while you watch TV. Pace the floor while talking on the telephone. All these moves add valuable minutes of physical activity to your day.
  • Try new activities to get in your exercise. Are you getting bored of walking around your block? Seek out new routes or explore hiking trails on the weekend. 
  • Exercise with a friend or a group. Positive social interaction combined with physical activity is a win-win for your body and soul.
  • Replace sugar-sweetened drinks with no- or low-calorie beverages. Try spritzing some fresh lemon or lime into seltzer water instead of drinking soda. Before long you won’t notice the difference in taste—but you’ll enjoy better hydration and fewer calories in your daily count.
  • Slow down while eating. Try to enjoy each bite of food and stop eating before you are too full. Being mindful of your body’s natural fullness cues can help you step away from the dinner table feeling satisfied but not overstuffed.

Attaining and maintaining a healthy weight is hard work. But when you start to see the benefits—less joint pain, more energy, lower risk of health conditions and a better outlook overall—you know your effort will have been worth it.


U.S. Department of Health and Human Services. Physical Activity Guidelines for Americans. 2nd edition. 2018. Accessed February 11, 2021.
U.S. Department of Health and Human Services. Watch Your Weight. My Healthfinder 2020. Accessed February 11, 2021.
U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2020-2025. 9th Edition. Accessed February 11, 2021.
Centers for Disease Control and Prevention. Keeping It Off. Healthy Weight, Nutrition, and Physical Activity 2019. Accessed February 11, 2021.
NIH National Institute on Aging. Maintaining a Healthy Weight. Accessed February 11, 2021.
Centers for Disease Control and Prevention. About Adult BMI. Healthy Weight, Nutrition, and Physical Activity 2020. Accessed February 11, 2021.
Mayo Clinic. Fitting in fitness: Finding time for physical activity. Accessed February 12, 2021.

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