How Much Weight Can You Lose in 3 Months?

The countdown is on. You've got about 90 days until the big event (a vacation, perhaps, or maybe a reunion) and you want to know: How much weight can I lose in three months?

Just how far you can move the scale in three months will vary from person to person, but there are some guidelines that will give you an idea of how much you can realistically shed.

Most health experts recommend you lose no more than 1 to 2 pounds per week, according to the Mayo Clinic. If you lose about a pound per week, you can expect to lose about 12 pounds at the end of three months.

At a weight-loss rate of 2 pounds per week, you may lose as much as 24 pounds in the three-month timeframe.

Keep in mind, though, that every person's specific rate of weight loss will vary, according to multiple factors, including your calorie deficit (more on that below) and exercise routine, along with factors that are mostly outside of your control, like your genetics.

Ready to get started? Here's your game plan:

A healthy goal for weight loss in three months for most people is between 12 and 24 pounds, but you need to decide what's realistic for you within that range. Losing weight isn't easy, and the more weight you want to lose, the more committed you'll have to be to changing your eating and exercise habits.

Especially if you have any underlying conditions, it's a good idea to talk to your doctor before you start your weight-loss journey, to make sure your weight-loss goal is a healthy one and to determine if there's anything in your medical history that might make it more difficult to shed pounds.

If your goal is to lose about 12 pounds in three months, that's about a pound a week, which means you'll need to burn 500 additional calories every day, either by cutting those calories from your diet or burning them via exercise (or a combination).

To lose about 24 pounds in three months, or 2 pounds per week, you'll need to increase that daily number to 1,000. That's because there's about 3,500 calories in one pound of fat, according to the Mayo Clinic.

In order to create a calorie deficit, you first need to know how many calories you need to maintain your current weight (your maintenance calories).

You can find your maintenance calorie value by tracking your food for several days using either a food diary or tracking app. Then, assuming you don't gain or lose any weight, you can use this value as the baseline for your calorie deficit.

You can also start with an estimate based on your age, sex and activity level, according to the Academy of Nutrition and Dietetics:

For people assigned female at birth:

For people assigned male at birth:

While fad diets can help you cut calories quickly, they'll probably do more harm than good. Building healthy habits you can keep up for the longer term is a better idea. Keep these tips in mind:

• ‌Prioritize whole foods.‌ Fill your plate with fruits and vegetables in a wide range of colors. Veggies are rich in vitamins and fiber, a nutrient that helps keep your digestion regular, according to the Academy of Nutrition and Dietetics.
• ‌Include carbohydrates.‌ Despite what current diet trends say, carbohydrates are another part of a healthy diet. While you should enjoy a croissant (or two) every now and again, you'll want to eat mainly whole grains or healthy carbohydrates like brown rice, sweet potatoes or whole-grain pasta.
• ‌Make sure you eat enough protein.‌ Eating enough of this macronutrient will help you hold onto muscle mass and keep your energy up while you're in a calorie deficit, according to the Mayo Clinic. To keep your overall calories low, prioritize lean protein sources such as poultry, fish or low-fat dairy.
• ‌Consider the Mediterranean diet.‌ Although it's not strictly a weight-loss diet, research has linked the Med diet to lower body weight and BMI. Plus, it checks all the boxes when it comes to whole foods, healthy carbs and lean protein.

To torch more calories in your quest to lose body fat quickly, add more movement to your day. The more active you are, the greater your daily calorie burn. This helps you lose weight faster, and will help preserve lean muscle, too.

Work up to a minimum of 150 minutes of moderate-intensity cardio weekly, which includes brisk walking or water aerobics, according to the Centers for Disease Control and Prevention. Or if you prefer shorter workouts, opt for 75 minutes of vigorous-intensity exercise, like high-intensity interval training.

You should incorporate at least two days of strength training into your weekly routine, too. Strength training can help improve your muscle mass and metabolism, according to Harvard Health Publishing. Plus, it will add some welcome variety to your workout schedule.

To shed 40 pounds in three months, you would need to lose a little over 13 pounds per month. That's a weekly deficit of about 11,375 calories, which is 1,625 calories per day.

Not only does this far exceed the maximum recommended calorie deficit, it's more than most people burn on an active day. In other words: It's nearly impossible to lose that much weight in three months.

For people living with obesity, doctors may sometimes prescribe a very low-calorie diet (VLC), which involve eating 450- to 800-calorie medically-prepared meals, according to the National Institute for Health and Care Excellence's November 2014 clinical guidelines.

However, these specific dietary interventions can be dangerous and should only be attempted with the support and supervision of a qualified medical professional. Generally, these plans involve a full supplement routine, ensuring the person gets all the vitamins and nutrients they need.

The deficit needed to lose 30 or 40 pounds in three months is unsustainable and probably won't allow you to take in the necessary calories for good health and energy. Plus, the results you see probably won't last in the long run.

On an extremely low-calorie diet, it can be hard to give you body all the nutrients it needs. Vitamins, nutrients and fiber are all a big part of your day-to-day and long-term health, according to the Academy of Nutrition and Dietetics.

For instance, if you don't give your body enough calcium, it's forced to draw from its own calcium stores in your bones. Over the long term, this can cause conditions like low bone density.

Not getting enough calories will also slow down your metabolism, which will ultimately make it harder to lose weight, per the Academy of Nutrition and Dietetics. A slowed metabolism may even cause digestive issues or constipation.

Gallstones are another potential side effect of very low-calorie diets, according to Johns Hopkins Medicine. Eating fewer than 800 calories a day increases your risk of developing this condition, which can cause abdominal pain, vomiting and fever.

As a weight-loss goal, 30 or 40 pounds is totally achievable — but not in three months. Instead of placing all your focus on the scale, prioritize building healthy habits. This will help you shed weight gradually and your new lifestyle will help you keep it off.