Healthy Weight Gain without the Burger and Fries

by Leah Frankel, MS, RD |

With over half of American’s classified as either overweight or obese, there is a plethora of information available on weight loss (not that we recommend the unusual “grapefruit diet” your Google search pulled up). While most of us in America are trying to lose weight, have you ever thought about the people out there trying to gain weight? According to the Center for Disease Control (2003-2006), approximately 1.8% of adults are underweight. Adults are underweight for a variety of reasons including a desire to be thin for aesthetic reasons, medical conditions and poor dietary intake (which is common in the elderly). As with being overweight, there are risks associated with being underweight; we’ll discuss these risks as well as common reasons for being underweight and walk you through how to gain weight in a healthy manner without a diet of burgers and fries.

Risks of Being Underweight

A body weight below the normal range (which we will call underweight) is defined as a Body Mass Index (BMI) below 18.5 kg/m² (You can calculate your BMI as follows: weight (kg)/height (m)²). There are a variety of risks associated with being underweight including increased risk of developing osteoporosis, anemia, difficulty becoming pregnant, vitamin or mineral deficiencies, increased risk of infection and amenorrhea (loss of menstruation). Several of the risks we listed are associated with inadequate intake of a variety of nutrients and risk of infection. The risk of developing osteoporosis is high in underweight individuals as a result of the combination of poor intake of calcium and a decrease in the amount of weight your bones support (Note: In response to weight lifting or carrying excess weight on your body, your bones become stronger. Astronauts have to do weight lifting exercises in space in order to prevent their bones from breaking down in zero gravity).  The picture above shows normal bone density (on the left) compared to significantly decreased bone density (on the right) as a result of  poor nutrition.

Why People are Underweight

People can be underweight for a variety of reasons including, but not limited to, eating disorders, cancer, hyperthyroidism, HIV/AIDS, poverty, loss of appetite, athletic demands and depression. In the elderly, weight loss is typically a sign of an underlying medical condition such as chewing or swallowing difficulties, confusion, or dementia.  Treating the underlying medical condition can lead to an improvement in appetitive and a return to their usual body weight. Even if elderly people are slightly overweight, weight loss is not typically recommended or desirable. When women try to become pregnant and are below a healthy weight range, they are typically encouraged to gain weight prior to trying to conceive. It is important that women are at a healthy weight while pregnant in order to provide enough nutrients for the fetus. As we discussed in the article on Pregnancy and Weight Gain, women who are underweight and pregnant are recommended to gain more weight than women in a healthy weight range to compensate for their initial sub-optimal weight status. While many football players are encouraged to gain weight, athletes such as wrestlers, cross country runners and gymnasts are often urged to lose weight for improved performance in their particular sport. In women, this weight loss can cause what is known as the Female Athlete Triad, which is a combination of symptoms due to extreme exercise and insufficient calorie intake. The Female Athlete Traid includes three conditions:

  1. Disordered eating
  2. Amenorrhea
  3. Osteoporosis

In conditions such as cancer, HIV/AIDS and hyperthyroidism, the body needs extra calories in order to properly function and maintain the same weight. People suffering from these conditions may find it difficult to maintain their weight due to their body’s high demand for calories. Additionally, treatments such as chemotherapy provide can cause nausea which may lead to a decrease in appetite and further weight loss (enter the need for the combined nausea suppressant/appetite stimulant, marijuana, in patients receiving chemotherapy).

Tips for Gaining Weight

In order to successfully gain weight, it is first necessary to address the underlying condition. For instance, a person with depression who has a poor appetite would benefit from treatment for the depression in addition to dietary recommendations for weight gain. Forcing someone to gain weight will not treat the real problem, in this case depression. At the same time, we can’t always cure the underlying problem.  We can’t always cure a person’s cancer but we can provide foods that are tolerable with nausea as well as foods that will assist in weight gain.

Before we discuss which foods are the best for someone trying to gain weight, we’re going to do a basic review of our three macronutrients: carbohydrates, protein and fat. In terms of calories, one gram of carbohydrates provides 4 calories, as does one gram of protein.  One gram of fat provides 9 calories. So what does this mean? If we were eating 100 g of a carbohydrates we’d consume 400 calories, but if we consumed 100 g of a fat we’d consume 900 calories (rocket science, we know).  For the same 100 g of food we get more than twice as many calories from fat. Foods that contain a lot of calories in a small quantity are known as calorically dense foods. People trying to gain weight should choose calorically dense foods in order to get the most bang for their buck!

Healthy High Calorie Foods

In order to gain weight, you need to eat more calories than your body burns, which is why some people turn to unhealthy but high calorie foods like donuts and pizza. While you can gain weight with unhealthy foods, you’ll likely be missing key nutrients. Here are some great foods to aid in healthy weight gain:

  • Avocados
  • Nuts
  • Cheese
  • Olive oil
  • Sour cream
  • Olives
  • Peanut/almond butter
  • Dried fruit
  • Sunflower seeds
  • Dried milk (add to dishes, such as casseroles)
  • Margarine

Looking at this list of foods you may notice a trend: many of these foods contain a significant amount of fat. As we mentioned earlier, fat contains more calories than protein or carbohydrates.   Adding healthy fats such as avocados or olive oil provides you with healthy fat and extra calories. In addition to these foods, snacking or eating 5 or 6 small meals a day can help increase calories consumed throughout the day. A study analyzing data from the NHANES Survey 1999-2002 compared adults who were snackers with nonsnackers (1). The snackers consmed on average, two and a half snacking occasions per day, with each snacking occasion contributing 150 calories. Interestingly, the calories consumed at meals did not differ between snackers and nonsnackers, suggesting that consuming snacks in addition to meals can lead to a greater caloric intake throughout the day. Finally, in order to consume more calories at meals, it’s beneficial to drink fluids before and after, not during, meals so that your stomach is less full during the meal.

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  1. Zizza CA, Tayie FA and M Lino. Benefits of Snacking in Older Americans. Journal of the American Dietetic Association 2007; 107:800-806.


09 2010

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