Rapid weight loss doesn't necessarily guarantee that you'll stay slim.

What Is the Most Weight a Person Can Lose in a Month?

by Van Thompson

If you're counting down to a big event or just sick of looking at a body you don't love, you might be wondering how quickly you can lose the weight. The amount of weight you will lose is directly related to your diet and exercise routine. Other factors, such as your overall health and starting weight, can also play a role. While you might be able to lose a significant amount of weight in a month, losing the most weight possible isn't always a healthy strategy.

Weight-Loss Basics

Losing weight means you'll have to eat fewer calories than you burn throughout the day -- sometimes called creating a caloric deficit. For most people, this means eating less food and doing more exercise than normal, and it can take quite a bit of work. A single pound of fat is equal to 3,500 calories, and burning calories isn't always easy. In 30 minutes of water aerobics, for example, a 185-pound person will only burn about 133 calories. This means that, if you're planning to rely on exercise alone, you'd have to do about 13 hours of water aerobics per week.

Healthy Weight Loss

Healthy weight loss enables you to get all the basic nutrients you need from your food, so that lessens the number of calories you can cut from your diet. Over-exercising can contribute to muscle pain, exhaustion and even overtraining syndrome, so regular -- but not excessive -- exercise should also be a part of your plan. MayoClinic.com advises doing about 150 minutes a week for weight loss and emphasizes that healthy weight loss usually means shedding a pound or two each week -- 4 to 8 pounds in a month. In the first days of a diet, however, you might lose more weight as you shed water weight, and people who are very overweight sometimes lose more weight in the first month.

Crash Diets

Crash diets are designed to help you lose weight quickly and could yield more weight loss than a healthy diet. However, these diets won't necessarily help you keep the weight off, particularly if you can't stick to the program for the rest of your life. In "Health at Every Size," nutrition professor Linda Bacon explains that crash and yo-yo dieting can actually slow your metabolism, causing you to gain more weight.


For every 3,500 calories you eliminate through diet and exercise, you'll lose a pound. Theoretically, then, you can lose as much weight as you want so long as you stick to a rigorous diet and exercise program. In reality, though, such a plan can severely endanger your health and constitute an eating disorder. Malnutrition can make you prone to cardiovascular problems, interfere with organ function, deplete your energy level, alter your mood and even kill you.

About the Author

Van Thompson is an attorney and writer. A former martial arts instructor, he holds bachelor's degrees in music and computer science from Westchester University, and a juris doctor from Georgia State University. He is the recipient of numerous writing awards, including a 2009 CALI Legal Writing Award.

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