A Weight-Gain Diet to Gain 2 Lbs. per Week

If you're interested in gaining 2 pounds a week, you could easily do it by eating unhealthy junk food. However, if you need to do it for health reasons, it's important to keep your diet nutritionally balanced.

If you're underweight, there are a number of health risks to worry about. According to the Mayo Clinic, 1 pound is equal to about 3,500 calories. That means you'd need to eat 7,000 extra calories every week to achieve your goal. That's 1,000 extra calories a day.

The key to getting your daily calorie intake right is to calculate your basal metabolic rate (BMR) or the number of calories you burn every day by just existing. According to the American Council on Exercise (ACE), your BMR varies based on a number of factors, including your body composition, gender, age, height, weight, diet, glands, body temperature, external temperature, exercise and genetics.

There are multiple formulas to use to calculate your BMR, though the ACE says the Miffilin-St. Jeor equation is more accurate. This formula for males is: 9.99 x weight (in kilograms) + 6.25 x height (in centimeters) - 4.92 x age (in years) + 5.

According to the Centers for Disease Control and Prevention (CDC), you are underweight if your BMI is less than 18.5. For instance, a 25-year-old male who is 5 feet, 10 inches tall and weighs 120 pounds, has a BMI of 17.2 according to the CDC calculator.

Convert weight in pounds to kilograms by dividing by 2.2. Convert height in inches to centimeters by multiplying by 2.45.

• 9.99 x 54.54 = 544.85 (weight)
• 6.25 x 171.5 = 1,071.87 (height)
• 4.92 x 25 = 123 (age)

Putting it all together, 544.85 + 1,071.87 = 1,616.72 - 123 = 1,494 + 5 = 1,499 calories/day. This is based on a sedentary lifestyle with little to no exercise. The more exercise you do, the more calories you'll burn and will need to eat to maintain your current weight.

The formula for females is similar: 9.99 x weight + 6.25 x height – 4.92 x age – 161. Changing the gender from the above example to a 25-year-old woman who is 5 feet, 10 inches tall and 120 pounds, the math looks like this: 544.85 + 1,071.87 = 1,616.72 - 123 = 1,494 - 161 = 1,333.

Read more: How to Build an Appetite for Weight Gain Naturally

Your diet should be focused on healthy weight gain. It'd be easy to get an extra 1,000 calories by taking a trip to a fast-food restaurant for a burger. However, it's much better for your overall health to add calories with lean proteins, healthy fats and complex carbohydrates. Avoid refined and processed food as much as possible.

To gain weight in a healthy way, the Mayo Clinic suggests eating smaller meals more often because you may feel full faster. Aim for five to six smaller meals instead of two to three large meals. Instead of drinking soda, coffee and other beverages with little nutritional value and calories, opt for smoothies and shakes that are made with fresh or frozen fruit and milk or yogurt.

If drinking before a meal dulls your appetite, sip on higher-calorie beverages along with your meal or snack. You can also try drinking 30 minutes after a meal, rather than with it. Add extras, such as cheese, to meals when possible for extra calories.

Remember, it's OK to have treats, but it's still important to watch for extra fat and sugar. Ideally, your weight gain should be muscle rather than fat. Exercise, including strength training, can help you build more muscle and may even stimulate your appetite.

Aim to eat something every hour, even if it's just a handful of nuts for a quick snack. Though you don't want to increase your portion sizes significantly, it's OK to add a bit more. For example, if you normally eat two eggs in the morning, eat three. Pour yourself an extra couple of ounces of milk with breakfast. Add sauces (that aren't full of sugar, of course) to your food to enhance flavor with some calories too.

Low-calorie fruits and vegetables are good for you, but you can easily fill up before you have enough to get the calories you need. Keep them in your diet for nutrition, but don't be afraid to include other higher-calorie foods like sweet potatoes and avocados. When it comes to dairy, opt for the full-fat versions to boost your overall calorie intake.

Read more: 4 Reasons You're Not Gaining Weight (Plus Easy Fixes)

After you have reached your goal weight, it is crucial to adjust your caloric intake to prevent further weight gain. You don't want to swing too far in the other direction toward obesity. The number of calories you should eat every day depends on your activity level.

If you continue to eat 1,000 more calories than your body burns every day, you will continue to gain an average of 2 pounds a week. This is OK when you're trying to move from underweight to healthy weight, but once you hit that healthy weight mark for your age, gender and body composition, you want to stop eating the additional calories so you can maintain the weight. Do this by reverting to low-fat or fat-free dairy products and reducing your portion sizes back to normal.

It may take a bit of experimenting to find the right number of calories. If you decrease your caloric intake and find that you're losing weight again, add a couple hundred more calories per day until you see the weight stabilize.

To maintain a healthy weight, according to the National Institute on Aging, you should limit portion size and be as physically active as possible. Ideally, you should strive for 150 minutes of moderate-intensity aerobic activity each week, broken up however you'd like. If you cannot do this much right away, something is always better than nothing.

If you think you weigh too much or too little, you should speak to your doctor. They can provide guidance specific to your situation by factoring in your health conditions and may refer you to a nutritionist to create a meal plan to help you reach and maintain your goals.