Fast weight gain isn't necessarily healthy weight gain. The main thing to remember is to eat more calories than you burn and to get them from nutrient-dense food. This approach can result in a gain of 1 to 2 pounds per week, which would add up to 4 to 8 pounds per month.
To gain weight in a month, add 300 to 500 calories to your daily intake. Choose foods with a high nutritional value such as fruits, vegetables, whole grains, beans, nuts, seeds, dairy foods and healthy fats like olive oil.
Women Are More at Risk
The American Council on Science and Health reports that four times more women than men are underweight. Women between ages 18 and 24 and those ages 65 and older have twice the likelihood of being underweight than other age groups.
Teenage girls, for example, often don't know what a healthy weight looks like. They may admire super-thin models in magazines or on television and want to lose weight to look like them, says GirlsHealth. However, many of these models are so thin that they're putting their health and even their lives at risk.
Body mass index (BMI) is a screening tool that can give you an idea of whether you're underweight. To check yours, go to an online BMI calculator and put in your height and weight. A BMI lower than 18.5 denotes underweight, a BMI of 18.5 to 24.9 denotes a normal weight and a BMI of 25 to 29.9 denotes overweight.
Parents who are concerned that a daughter may be underweight should calculate her BMI, but also watch for signs of thinness such as how her clothes fit, advises the Cleveland Clinic. When your daughter is at the beach, for example, note whether her ribs protrude prominently.
If you're underweight, or your daughter is, a health practitioner can prescribe a weight-gain program. The approach for women and girls would be the same as the approach for men and boys. It involves consuming more calories than you burn — but the calories need to come from nutritious foods instead of from junk food like donuts, candy bars and chips.
Healthy Weight Gain in Women
The American Academy of Family Physicians recommends a healthy, balanced strategy for weight gain. Eating foods high in sugar, white flour and unhealthy fat will help pack on pounds, but they won't provide the nutrients you need. In addition to failing to supply vitamins and minerals, such foods can cause the same health problems in the underweight as they do in the overweight.
Add 300 to 500 calories per day to your diet that is beyond what you normally consume, advocates the American Council on Exercise. Shun empty-calorie foods in favor of nutrient-dense foods like fruits, vegetables and healthy sources of protein. Eat complex carbohydrates like brown rice and other whole grains, says the American Academy of Family Physicians.
It isn't necessary to dramatically change your diet. Cheese, nuts and seeds will add calories. Fruit will also increase your caloric intake.
Choose snacks that are rich in healthy carbohydrates and protein such as protein bars, trail mixes and whole-wheat crackers with peanut butter or hummus. Healthy-fat foods like avocados and nuts also make good snack options.
Read more: Home Remedies to Gain Weight in One Week
Drink nutritious smoothies, suggests Mayo Clinic. Instead of sodas, diet sodas and other drinks with little nutritional value, whip up delicious shakes made of milk, fruit and a sprinkle of ground flaxseed.
If your appetite is poor, it may be easier to eat several mini meals per day rather than three larger ones. The Mayo Clinic also says to avoid drinking before a meal because it might reduce your appetite.
Several things can result in a person being thin notes the American Academy of Family Physicians. It can stem from thyroid disorders, cancer, diabetes or digestive problems. Depression and stress may also play a role.
Weight Gain in Young Girls
All the weight-gain tips for women are applicable to young girls, but parents of underweight children should consider a few additional guidelines, notes the Cleveland Clinic. Avoid fruit juices, juice drinks and sugary beverages because they can fill a child without providing nutrients. Protein powders aren't recommended for children.
Although snacking is encouraged, excessive eating between meals will curtail the appetite when the child sits down to a balanced meal. When preparing food, add extra drizzles of a healthy oil, such as olive oil, to sneak in extra calories. Drinking an oral nutritional supplement like Ensure can also help.
A number of issues cause thinness in children. Medications, such as those for attention deficit-hyperactivity syndrome, can reduce the appetite, states the Cleveland Clinic. Food allergies may get in the way of ingesting enough calories. Digestive or hormonal disorders decrease nutrient absorption.
Weight Gain for Vegetarians
While healthy weight gain for vegetarians is achieved in much the same way as it is for nonvegetarians, they should take extra care to eat foods that prevent the nutritional deficiencies associated with these diets. Harvard Health says vegetarians need to be extra creative in their meal planning to make sure they get enough foods containing protein, calcium, vitamin B12 and iron.
The Academy of Nutrition and Dietetics notes that the protein in eggs, dairy products and soy products is easily digestible and has all nine essential amino acids. Vegetarians are often interested in increasing muscle size, and eating high-quality protein at each meal will help accomplish this goal.
Eating fatty fish — such as salmon — and flaxseed will supply heart-healthy omega-3 fatty acids. Aside from dairy foods, adding green, leafy vegetables to your diet will provide calcium, says the United States Department of Agriculture. Incorporating whole grains and beans in the diet supplies iron, and eating dairy products and eggs provides B12.
Underweight Health Risks
For women, being underweight can reduce the production of female hormones and affect fertility, states the American Council on Science and Health. Even just a 5-pound weight loss can adversely affect the menstrual cycle. Pregnant women need a certain amount of fat to have a healthy infant.
Some health risks associated with being underweight affect both sexes. These include bone loss, nutritional deficiencies and heart disorders, states the Washington State Department of Social and Health Services. Being underweight impairs immunity, resulting in a higher risk of infections and delayed wound healing.
Additional risks include headaches, dizziness and fatigue associated with anemia. Low weight is also linked to thinning hair, dry skin and issues with gums and teeth.
- American Council on Science and Health: "Trying to Gain Weight"
- GirlsHealth.gov: "A Healthy Weight for Girls"
- Centers for Disease Control and Prevention: "Adult BMI Calculator"
- Cleveland Clinic: "A Dietitian’s Best Advice If Your Child Is Underweight"
- American Academy of Family Physicians: "Healthy Ways to Gain Weight If You’re Underweight"
- American Council on Exercise: "Diet Tips for Gaining Weight"
- Mayo Clinic: "What's a Good Way to Gain Weight If You're Underweight?"
- Harvard Health: "Is a Vegetarian or Vegan Diet for You?"
- Academy of Nutrition and Dietetics: "Building Muscle on a Vegetarian Diet"
- USDA: ChooseMyPlate.gov: "10 Tips: Healthy Eating for Vegetarians"
- Washington State Department of Social and Health Services: "Underweight: Health Risks"