For Men: Pros and Cons of 7 Popular Supplements

Once upon a time, pills, powders, and shakes promising to build muscle and enhance energy were marketed strictly to bodybuilders and professional athletes. But now, it seems every gym, health food store, and supermarket stocks a variety of supplements aimed at anyone looking to slim down, bulk up, or build stamina. While many weight-loss products target female consumers, a vast array of supplements is designed specifically for men.

According to data from the CDC, just over half of adult men take supplements. Men may take supplements for a variety of reasons, including heart health, bone and joint health, or eye health.

Many supplements marketed to men are advertised as surefire methods for enhancing athletic performance, aiding in weight loss, and building lean muscle. Despite these claims, it’s important to keep in mind that supplements aren’t regulated by the Food and Drug Administration (FDA), and it can be difficult to distinguish which ingredients are actually beneficial.

Here’s a look at the pros and cons of some of the most popular supplements for men.

What it is: A natural substance that is converted in the body to help make adenosine triphosphate (ATP), which provides energy for muscle contractions.

Benefits: Creatine gained popularity for helping users enhance athletic performance and build lean body mass. It has been found to enhance performance in high-intensity, short-duration exercise, and decrease recovery time in between exercise sessions.

Side effects: Stomach pain, nausea, diarrhea, muscle cramping, and temporary weight gain due to muscles retaining water. People with kidney problems should not take creatine.

What it is: Protein powders come in various forms, but the most common are whey, soy, and casein. They can help increase the amount of complete, high-quality protein in a variety of food and beverages.

Benefits: Proteins facilitate crucial cellular functions, and complete proteins, like those in protein powders, contain all 20 amino acids necessary to form protein molecules. In the short term, high-protein diets have been shown to increase fat burn, increase satiety, and possibly lead to weight loss.

Side effects: High doses of protein powder can cause increased bowel movements, bloating, cramps, reduced appetite, fatigue, and headache. Taking in very high amounts (more than 2-3.5 grams per kilogram per day) of protein for too long can lead to kidney problems.

What it is: Glutamine is an amino acid that the body produces naturally. It’s important for removing excess waste products, healthy immune system function, and may play a role in normal brain function and digestion.

Benefits: Research hasn't consistently shown a benefit for supplementation in healthy adults - healthy adults generally make enough glutamine in their bodies naturally. There is some research that suggests glutamine may help speed recovery from injuries, surgery, or critical illness.

Side effects: Glutamine may be dangerous for some people, worsening cases of cirrhosis, mania, seizures, and other conditions. More common side effects include cough/hoarseness, frequent urge to defecate, and straining while passing stool.

What it is: Glucosamine is a naturally occurring substance found in the fluid around joints, and plays an important role in building cartilage.

Benefits: Some research suggests that glucosamine sulfate may help treat osteoarthritis, but there is little evidence of any significant effect.

Side effects: Generally safe, but some people experience nausea, heartburn, diarrhea, and constipation.

What they are: Prohormones are hormone precursors that the body can supposedly convert into the appropriate hormones. Prohormones of testosterone androstenedione, androstenediol, and dehydroepiandrosterone (DHEA) are commonly used by bodybuilders to get the benefits of anabolic steroids without the legal risk, but some prohormones are also outlawed.

Benefits: Current research indicates that prohormones have little or no proven benefit.

Side effects: Side effects are specific to each type of prohormone, but possible effects include acne, hair loss, liver damage, and enlarged breast tissue.

What it is: Nitric oxide, a gas produced by the body, enables cells to communicate and can affect the release of hormones and adrenaline. Many pre-workout supplements contain L-arginine that the body converts into nitric oxide.

Benefits: Dietary nitrate (from sources like green leafy vegetables and beetroot) increases nitric oxide bioavailability, which has been shown to lower blood pressure, improve vascular health, and enhance exercise performance in healthy individuals. L-arginine supplementation can lower blood pressure by a small amount in some people, but has not been consistently shown to improve strength, power, or recovery for exercise.

Side effects: L-arginine can cause abdominal pain, bloating, diarrhea, gout, blood abnormalities, allergies, airway inflammation, worsening of asthma, and low blood pressure.

What it is: A crystalline compound that stimulates the central nervous system, caffeine is a common ingredient in many pre-workout supplements, and is thought to increase energy and enhance performance.

Benefits: Caffeine has been shown to reduce feelings of exertion and improve performance during activities like cycling, running, soccer, and golfing, but doesn’t seem to improve performance in short-term, high-intensity exercise such as sprinting and lifting.

Side effects: Caffeine can cause insomnia, nervousness and restlessness, stomach irritation, nausea and vomiting, increased heart rate and respiration, and other side effects. Caffeine can make sleep disorders worse, and larger doses might cause headache, anxiety, agitation, chest pain, and ringing in the ears.

The supplement market is flooded with products commonly marketed by untrained salespeople, with little to no discussion about potential side effects. In addition to the monetary cost of supplements, which can be prohibitively high for some, the side effects can be serious, and some cases, permanent. Always consult a medical provider before initiating a new supplement regimen. Your health care provider will be able to discuss the pros and cons of supplementation with you in a more equitable way, and possibly offer safer alternatives.