Are you a teenage girl or the parent of a young teen who needs to gain weight fast? In this post, I will discuss the most effective ways to achieve this, whether it be to improve athletic performance, restore menstrual function, or improve overall health outcomes of a health concern. You will receive a clear answer to the question, how can a teenage girl gain weight fast?

Needing to gain weight fast is no easy feat for everyone, but there are ways to do it without creating problems later on. Today, I will guide you through the best way to gain weight fast as a teenage girl to avoid additional health issues. 

As a female health expert, I have worked with hundreds of young women and have helped them gain weight properly for years. I will bring those tips and tricks to this article so you can achieve optimal health the quickest way possible. 

Let’s get started!

Why Would a Teenage Girl Need to Gain Weight Fast?

If a teenage girl is underweight due to intentional food restriction, has a very active metabolism, participates in a high level of activity, or for other reasons, this can result in health complications with growth and development. Here are some other reasons why fast weight gain may be needed in this population. 

  1. Underweight or Low BMI: Some teenage girls may have a low body weight or BMI (Body Mass Index), which could mean they are not consuming enough food and calories for their height and age. Research has shown that BMI can lead to hormonal imbalances, weakened immune health, and nutritional deficiencies.[1] 
  1. Poor Nutritional Intake: It is very common for teenage girls to fall victim to diet trends and societal pressures to be “skinny.” This can result in intentionally eating in a calorie deficit. Undereating and underfueling can stunt growth and lead to poor production of hormones for teenage girls, which is why it’s important to get on top of it right away when symptoms pop up. Some teens may be so busy that they lose track of eating enough calories due to busy schedules, but poor intake is poor intake and should be addressed. It can lead to the same health problems, regardless of whether it is purposeful or not. 
  1. Medical Conditions: Certain medical conditions or illnesses, such as digestive issues like inflammatory bowel disease, hyperthyroidism, or cystic fibrosis, can make weight maintenance and gaining weight very tough for teenage girls. In conditions such as cystic fibrosis, a higher BMI is correlated with improved clinical outcomes, which is why weight gain is important in this population.[2] 
  1. High Activity Level: Teenage girls who are high-performing athletes who go from practice to lifting to school and back to practice have higher energy requirements. To sustain activity and recovery and allow for proper growth and hormonal balance, more calories are needed than in less active teenage girls. When under massive amounts of physical and mental stress, adrenal dysfunction can be the result of not eating enough food. Also, if teenage girls burn more calories than they consume for an extended period of time, weight loss may go unnoticed, and performance suffers heavily. 
  1. Recovery from Illness or Surgery: In some situations, we have athletes who sustain an injury and need surgery. Due to the recovery process, this can require an extended period of time away from exercise and weight lifting. The result? Weight lost in the form of muscle. If enough weight is lost, a fast weight gain upon returning to training to regain lost muscle mass and high-performance capacity would be helpful.

Regardless of the reason for needing to gain weight, it’s important to prioritize health and well-being throughout the process. Rapid weight gain through unhealthy or extreme methods can have negative consequences on both physical and mental health in teenage girls.

This is where our team, as performance dietitians, can help develop a safe and effective plan for achieving and maintaining a healthy weight in young teenage girls!

Group of teenaged girl athletes competing in sports and needing to be mindful of maintaining a healthy weight.

How Can a Teenage Girl Gain Weight Fast in a Healthy Way?

Sure, running to the donut shop every morning sounds like a delightful plan (literally) to achieve fast weight gain, but fast weight gain can be achieved in a more nutritionally balanced way that can avoid future issues from high amounts of processed foods. 

Use Healthy Fats to Your Advantage

Foods high in healthy fat are key to fast and healthy weight gain because dietary fat is the highest in calories compared to any other macronutrient. They are also low in volume, meaning it’s easy to eat a high amount of fat without feeling very full right away. 

Healthy fats are the backbone of building hormones!

For women looking to regulate their menstrual cycle, it is recommended that they eat sufficient fats at every meal and snack. 

Foods high in calories don’t have to be processed and full of junk. Foods that are high in calories but also rich in nutrients to fuel on would include nuts, seeds, avocados, nut butter, organic dairy if tolerated (i.e., whole milk, cheese, Greek yogurt, and cottage cheese), high-quality organic grass-fed beef, fatty fish such as wild-caught salmon, whole grains, grass-fed butter, and healthy oils like coconut oil, avocado oil, and olive oil.

For example: Add peanut butter to oatmeal, mix cottage cheese into scrambled eggs, or top a baked potato with cinnamon and melted coconut oil.

The goal here is to make eating EASY for yourself! This is the time to focus on high-calorie foods that are rich in dietary fat. It’s still important to incorporate some high-fiber fruits and veggies as they are beneficial for gut health and gut healing

However, too many of these foods can fill you up quickly without contributing much from a calorie perspective.  

Small meals and snacks more frequently

There is a time and a place for intermittent fasting. Intermittent fasting can be very beneficial for health and digestion in many situations but is not typically a recipe for success when trying to gain weight fast and in a healthy manner. This is because your window of eating throughout the day is shortened, making it hard to fit all necessary meals and snacks in without feeling uncomfortably full. 

Many times, teenage girls will also skip out on eating in the first half of the day when their appetite is lower. 

Instead of skipping breakfast, grazing at lunch, and eating a massive dinner, space food evenly throughout the day. 

The goal would be three small to moderate-sized meals with 2-3 snacks in between. This can help increase overall calorie intake without feeling stuffed and will also support energy and performance throughout the day. 

Pro-Tip: If you do not typically feel very hungry in the morning, the next suggestion would be a great place for you to start. Just know that over days to weeks, your appetite will pick up as it adjusts to eating more in the beginning of the day. 

Drink liquid calories when possible

How can a teenage girl gain weight fast without feeling incredibly stuffed all day? Liquid calories!

In situations where fast weight gain is the goal, drinking fluids with added calories can be helpful. Sometimes eating food constantly gets old, and fluids go down easily! Some examples of liquids to drink for weight gain include:

  • Smoothies made with protein powder, coconut milk, peanut butter, and other ingredients of choice 
  • 100% orange juice
  • Chocolate oat milk
  • Full-fat coconut milk

Drinks such as smoothies in the morning tend to be much easier for young teenage girls to tolerate in the morning when their appetite is not very strong. 

Calorie dense snacks 

Single RAWR Organics all natural protein bar in wrapper.

Snack on foods that are low in volume but high in calories. This is not the time to be eating loads of vegetables or foods high in fiber and water because these foods will fill you up without providing sufficient calories. 

Examples of high-calorie/low-volume snacks

  • Trail mix or mixed nuts
  • Simple mills crackers with organic cheese and turkey slices
  • Dried fruit such as dried mango and dried cranberries or dates 
  • Smoothies topped with Lovebird cereal or Purely Elizabeth granola
  • Smoothies with added protein powder, chocolate oat milk, and frozen avocado 
  • RAWR bars 
  • Go Macro bars
  • Banana topped with Oat Haus Granola Butter, or eat that stuff straight from the jar!

Notice that all of these swaps are higher in calories but still based on REAL, whole foods that are rich in vitamins and minerals, low in inflammatory ingredients, and still delicious. 

***Fast weight gain does not need to mean fast food and takeout!

Protein Protein Protein

How can a teenage girl gain weight fast to improve performance and recovery? Build muscle with sufficient protein intake! 

Protein is essential for building and repairing tissues, including muscle, which will make for effective weight gain. Foods high in protein include organic animal products like eggs, chicken, turkey, beef, fish, organic dairy products, and quality whey protein powder or plant-based protein powder. Increased protein intake can also support increased lean muscle mass, aka positive weight gain![3] 

Limit Empty Calories

While it’s important to increase calorie intake, avoid consuming excessive amounts of added sugars or processed foods, as they provide calories without much nutritional benefit and may lead to more inflammation in the body. 

**Disclaimer: some processed foods and sugar may actually be healthy for young teenage girls intending to heal from eating disorders or have a history of being overly restrictive with eating only “healthy foods.” **

Simple sugars are also warranted right before, during, and after workouts as this sugar can be used immediately for exercise and can avoid digestive woes during exercise. 

Girl working out and stopping to drink water with electrolytes by the best electrolyte water brands.

Hydrate Smartly

How can a teenage girl gain weight fast and also stay hydrated? Time hydration in a smart way. 

We all know that overly full feeling after we chug an entire bottle of water, and doing this around meals can make adequate intake of food a massive challenge.  

Drinking lots of water and electrolytes is important for exercise and recovery, but we recommend trying to avoid drinking large amounts of fluids right before or during meals, as this can reduce appetite and make appropriate weight gain a challenge. It can also dilute natural stomach juices and enzymes, which can lead to feeling bloated and uncomfortable after meals. 

What is a Proper Amount of Weight Gain for a Teenage Girl

How can a teenage girl gain weight fast without being concerned about gaining weight TOO quickly? Keep reading…

All girls will gain weight at different rates based on their bodies, but generally speaking, about 1-2 pounds per week is a safe and healthy weight gain goal to maintain for several months. 

It may not look the same every single week. Often times weight gain can be faster in the beginning and then slow down, or vice versa, so really, you’re looking for an average of about 1-2 pounds per week over several weeks to months.

Common Barriers to Effective Weight Gain in Teenage Girls

The weight loss happened in the first place, right? So for many girls, weight gain is going to present some challenges. Let’s discuss some common ones and how to overcome them.

Low Appetite

It’s very common for teenage girls to have a low appetite, especially in the morning. If they are very active, appetite can be further suppressed due to stress hormones from high-intensity exercise. 

To fight this, it’s important to start eating early. Fasting too long in the morning can further suppress appetite hormones and lead to low-calorie intake by the end of the day. Aim to start eating within 30 minutes of waking to fire up metabolism and support sufficient intake as the day goes on.

As mentioned, low appetite is also common after exercise because stress hormones are high. 

Encouraging teenage girls to get liquid calories in immediately after exercise can help them fight through this because fluids are much easier to get down compared to solid food. These sources should be rich in carbohydrates and protein to replenish glycogen stores and rebuild muscle. 

Examples include:

  • Osmo Power Fuel mixed with oat milk
  • UCAN Energy Powder
  • Applesauce or baby food packets
  • SFH Recovery Whey 
  • Protein shake with oat milk
  • Blended smoothie with avocado, protein powder, granola butter, and frozen fruit 

Too Busy

Busy schedules with school, extracurricular activities, and social commitments can put eating food on the back burner or lead to little snacks that do not contribute much to overall calorie needs. 

The lesson here is to be prepared! Always be prepared with high-calorie to-go snacks that can be consumed, whether you’re in between practices, staying late at school for extracurriculars, or hanging out with friends. Here are some of our favorite high-calorie, yet nutritious snacks to take on-the-go!

  • RAWR bars 
  • OWYN protein shake
  • Enjoy Life protein bites
  • Dried mango and dates
  • RX to-go nut butter
Teenage girl on a scale and fearful of the number.

Fear of Weight Gain

How can a teenage girl gain weight fast without becoming stressed about the change in their physical appearance? This can definitely be a challenge because teenage girls, particularly those spending time on social media, can develop massive pressure to look the part of an athlete or simply fear putting on body fat. 

This mindset can lead to restrictive eating behaviors, avoidance of calorie-dense foods, or excessive exercise practices in order to maintain or achieve a perceived ideal body shape. 

This can negatively impact weight gain goals and perpetuate loss of menstruation and female hormonal imbalances.

To support teenage girls dealing with these struggles, it’s important to encourage improving their performance and improving overall health as the focus. Additional mental and emotional support such as through therapy and working with a psychologist, would also be very important!

Digestive Issues

Eating is all fun and games until you hit the point where eating hurts or is uncomfortable! 

How can a teenage girl gain weight fast if she is dealing with chronic digestive problems such as irritable bowel syndrome (IBS), food intolerances, or other gastrointestinal disorders that leave you feeling bloated, constipated, or dealing with acid reflux? 

Not to mention, these issues can prevent one from being able to fully digest and absorb nutrients from food, making you essentially climb an uphill battle to gain weight. Research shows that patients with irritable bowel disease have been shown to be at risk for undernutrition.[4] 

One of the best ways to support weight gain in an individual with digestive issues is to first get to the root of why the digestive issues are there in the first place! 

Whether it be imbalances of bacteria in the gut, environmental exposures such as toxic mold, or food sensitivities, identifying and treating these imbalances can drastically reduce symptoms, making eating MUCH more feasible. 

If you want health coaching to uncover the root of your digestive issues, we offer a free 15-minute strategy call to map out a plan for working together to get the personalized treatment you’ve been looking for! 

With the help of an expert, you can learn which foods feel good for your body, allowing you to eat more food without discomfort.

A few other options that have been shown to support improved digestion and reduction of digestive symptoms like bloating and gas would be using gut healing powders for healing leaky gut and/or digestive enzymes. Digestive enzymes in a supplement form can replace our natural enzymes that may be lacking with various digestive conditions or in times of high stress. 

Research has even shown that in situations of bloating, gas, and uncomfortable symptoms after eating, consuming digestive enzymes on an empty stomach can reduce unwanted symptoms you may get after eating a high-fat meal. [5]

Lack of Knowledge or Support

How can a teenage girl gain weight fast if she doesn’t know how? Well, she probably can’t, so educating young women on how to properly fuel is step number one! 

To no fault of their own, many young girls simply do not have the proper education to eat a diet that satisfies their nutritional needs. Much of the available information is misinformation that is ineffective or potentially harmful for maintaining a healthy weight and will not help a teenage girl gain weight fast. 

On our website, we provide tons of free guidance for young athletes on how to fuel properly! 

Whether it’s learning the recommended carbohydrate intake for athletes or learning what foods cause inflammation in the body, it is very important that young teenage girls start learning about proper nutrition from an early age. 

This is where consulting with a healthcare professional, such as a registered dietitian and/or a mental health professional, can provide the guidance and support needed to overcome these physical and mental barriers and achieve healthy and fast weight gain.

We hope today’s article has answered the question, how can a teenage girl gain weight fast? 

Remember that while gaining weight efficiently can be done, it should be done gradually over several weeks to months, using nutritious foods to support energy, immunity, and overall health and well-being.