Safety and Effectiveness of Pills for Weight Gain

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In a society that is often fixated on losing weight, it might surprise you to know that some people want (and need) to gain weight. It's becoming increasingly popular to take pills to pack on the pounds, similar to taking supplements that claim to reduce body fat.

If you are frustrated by having an ectomorph body type or want a more curvaceous figure, you might have considered using pills to gain weight. However, you should know that there are many unknowns and possible safety concerns with weight gain supplements.

Before you take any supplement—even one you can get over-the-counter (OTC)—you need to know what's in it, how it is intended to be used, and the risks associated with it.

If you're still curious about weight gain pills, you need to start by talking to your healthcare provider about any product you are thinking about taking. Here is what you need to know about using a weight gain supplement, as well as why you need to work closely with your provider if you decide to try one.

What Are Weight Gain Pills?

Weight gain pills are drugs or supplements that are meant to help you put on weight. The products can be purchased over-the-counter, or in some cases, prescribed by a physician. Most OTC supplements guarantee that you can gain weight naturally and safely, but products purchased OTC are unregulated—which means they can make claims that are not backed by scientific evidence.

Prescription weight gain pills can include anabolic steroids. Your provider might prescribe this type of medication to help you gain weight if you have experienced significant weight loss and are underweight because you have an illness, such as cancer.

Athletes and bodybuilders might obtain and use prescribed drugs illegally to build muscle and enhance athletic performance. Using anabolic steroids inappropriately has been shown to have potential health risks—some of which are serious. It's vital that you only take these drugs when you are under the care of a physician.

Why People Use Weight Gain Pills

Common reasons that people consider weight gain supplements include:

  • They have an ectomorphic ("skinny") body type, which makes it hard to gain weight.
  • They have experienced severe weight loss caused by a serious illness, surgery, or infection (in which case prescription medication might be needed to help them regain weight).
  • They are lean bodybuilders who are hoping to increase muscle mass and overall size.

Over-The-Counter Weight Gain Pills

There are several weight gain pills that are available over-the-counter at groceries, big box stores, and pharmacies. Like many other supplements, these products are typically packaged and marketed with outlandish guarantees.

Weight gain pills often claim to increase appetite, slow metabolism, and place added pounds where they’re needed. Just as there is no such thing as spot reduction for weight loss, taking a pill will not allow you to spot place gained weight. Furthermore, considering that metabolism is shown to help regulate hunger cues, your appetite would not increase if that process is slowed.

If a weight gain pill or other supplement makes claims or guarantees that sound unbelievable, consider it a red flag.

Supplements, including weight gain pills, are unregulated by the Food and Drug Administration (FDA). The lack of regulation means that supplement producers can make false claims in their marketing to sell their products.

Many of these products are also not supported by clinical research. According to Mascha Davis, MPH, RDN, and National Media Spokesperson for the Academy of Nutrition and Dietetics, supplements are generally not tested as rigorously as drugs are, which means there are many safety concerns. Supplements also carry the risk of possible contamination.

There is no guarantee of the safety, effectiveness, potency, or purity of most OTC supplements.

CB-1 Weight Gain Pill Ingredients

According to Davis, a popular weight-gain supplement is CB-1. These weight gain pills are a trademark brand that makes many claims—from having clinically tested ingredients to gaining quality weight that you maintain.

The main ingredients in CB-1 are vitamin D3 and a weight gain blend that includes Echinacea. Numerous studies have shown that having low levels of vitamin D is associated with obesity and that increased levels help with weight loss (it's unclear why the makers of CB-1 would claim that an ingredient shown to help people lose weight would promote weight gain).

Echinacea is also included in CB-1 for weight gain. Although the current research is not definitive, the herb might help the immune system fight off colds and infections. Research has also suggested that Echinacea might have some anti-inflammatory benefit but there is no evidence linking the herb to weight gain.

Other studies have indicated that Echinacea should not be recommended for people with cardiovascular diseases. Echinacea may have the potential to increase the risk of cardiac arrhythmia (irregular heartbeat) in people with heart conditions.

Many OTC weight gain pills like CB-1 appear to be nothing but glorified, expensive, multi-vitamins. Most products also contain blends—a sneaky way that supplement producers can list ingredients without noting the dose amounts. Supplements with blended ingredients have the potential for adverse health effects.

Adverse Effects and Risks

  • Adverse effects of weight gain pills like CB-1 can include nausea, upset stomach, and diarrhea.
  • Individuals who are sensitive to herbs and grasses might have an allergic reaction (including asthma symptoms, skin rashes, or anaphylaxis).
  • People with heart conditions might be at an increased risk for an irregular heartbeat.

Common Prescription Weight Gain Pills and Side Effects

Prescription weight gain pills are sometimes preferred over those that are available over-the-counter. You need to be evaluated by a healthcare provider and get their approval before you can get this type of treatment.

Most prescription drugs for weight gain contain anabolic steroids, which are typically prescribed to treat specific medical conditions and come with side effects and risks. Here are three common weight gain pills that a healthcare provider might prescribe.

  • Methyltestosterone. An anabolic steroid that is primarily used to boost testosterone levels in males who have androgen deficiency (low levels of male sex hormones). Athletes might use this drug and other anabolic steroids to put on weight, increase muscle mass, and strength. Anabolic steroids are illegal for the enhancement of athletic performance.
  • Oxandrolone. An anabolic steroid that is also is known as Anavar. It’s primarily used to promote weight gain in patients who have experienced weight loss after extensive surgery, chronic infection, or severe trauma. It can also be used as hormone replacement therapy for males with low testosterone levels.
  • Oxymetholone. A synthetic hormone that is considered an anabolic steroid. It is primarily used to promote weight gain in patients who have lost weight during the course of having a debilitating disease. Patients might also be prescribed this drug to gain weight after having extensive surgery, chronic infection, or severe trauma.

Sometimes, prescription weight gain drugs are obtained illegally and used without any guidance from a physician. Athletes and bodybuilders are particularly likely to misuse these medications to enhance their appearance and athletic performance.

Anabolic steroids have many possible side effects Some of the most common side effects reported by people using the medication include:

  • Breast development (in males)
  • Delusions
  • Enlarged clitoris
  • Enlarged heart
  • Extreme irritability
  • Impaired judgment
  • Increased facial hair
  • Kidney problems or failure
  • Liver damage
  • Mood disorders
  • Mood swings
  • Prostate cancer
  • Shrinking testicles
  • Stopped menstrual cycle
  • Stunted growth (in children and teens)

Do Weight Gain Pills Work?

According to Davis, the evidence for the effectiveness of weight gain pills is limited. If you need to gain weight, there are healthier, safer, evidence-backed ways to do so. Davis recommends achieving weight gain by adding more calorie-dense foods to your diet.

Everyone is different and what works for one person who needs or wants to gain weight might not work for someone else. Working with a registered dietitian can give you personalized recommendations for what your body needs to gain weight in a healthy, safe, way.

Tips for Gaining Weight Without Pills or Supplements

Instead of looking for a quick fix to put on a few pounds, try taking a closer look at what you are eating. You might not be getting enough nutritious high-calorie foods in your diet to support weight gain. 

If you have been unable to successfully gain weight (and not just fat), several factors might be at play, including:

  • Dehydration. Staying hydrated is necessary for your overall health, but it's also key for optimum body composition. Water keeps the cells in your muscle tissue hydrated and promotes muscle growth.
  • Not eating enough. You might not be eating enough calories to promote weight gain. In fact, you might actually be eating for weight loss. To gain weight, your caloric intake must be greater than your energy output. Active individuals will require more calories to avoid putting their body in a deficit. Adding lean proteins and healthy fats (such as avocado) is a great way to get more nutrient-dense calories to help achieve quality weight gain.
  • Poor diet. Your current diet might be lacking quality healthy foods, such as lean proteins, vegetables, fruits, grains, nuts, and seeds. Eating a diet that is rich in nutritious food is necessary to properly fuel your body.

A Word From Verywell

People come in all shapes and sizes. According to nutrition expert Mascha Davis, our genetic makeup can play a big role in our body type. Even if you lift weights and eat a high-calorie diet to fuel your body and increase muscle mass, you might just be more likely to be slim because of your genes.

Davis suggests nutrigenomic testing to look at your DNA and nutrition and providers the best foods for a specific person based on their genetic makeup.

On the other hand, sometimes a person is unable to gain weight because they have a serious medical condition. If you have been losing weight without trying or are unable to maintain or gain weight to be at a healthy weight, talk to your provider. You might need to be tested for conditions such as hyperthyroidism, which can make it harder for people to gain weight.

While the claims and promises of over-the-counter weight gain pills might look promising, do not take these supplements without talking to your healthcare provider. They can have serious side effects and risks, and there are other options for gaining weight safely.

Speak with your healthcare provider and a registered dietitian if you are having a hard time gaining weight. Depending on the underlying reason you are unable to gain weight, specific recommendations will be made for you. It might be that you need to start by making changes to your diet. If your provider thinks a medication could be helpful, they will prescribe one for you.

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Article Sources
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  1. Anstey M, Desai S, Torre L, Wibrow B, Seet J, Osnain E. Anabolic Steroid Use for Weight and Strength Gain in Critically Ill Patients: A Case Series and Review of the Literature. Case Rep Crit Care. 2018;2018:4545623. doi:10.1155/2018/4545623

  2. Demling RH, Desanti L. Oxandrolone, an anabolic steroid, significantly increases the rate of weight gain in the recovery phase after major burns. J Trauma. 1997;43(1):47-5 doi:10.1097/00005373-199707000-00012

  3. Anabolic steroids. National Institute on Drug Abuse

  4. Healthy ways to gain weight if you're underweight. familydoctor.org. American Academy of Family Physicians

Additional Reading
  • National Center for Biotechnology Information. PubChem Compound Database. Oxandrolone.

  • National Center for Biotechnology Information. PubChem Compound Database. Oxymetholone.

  • National Center for Complementary and Integrative Health. Echinacea.

  • U.S. Library of Medicine. HSDB: 17- Methyltestosterone. Toxicology Data Network.

  • Wolfram T, MS, RDN, LDN. Healthy Weight Gain. Academy of Nutrition and Dietetics. 2017