7 supplements a personal trainer and bodybuilding coach takes daily to grow muscle, boost energy, and stay in shape

• Physique coach and former bodybuilder Cliff Wilson takes supplements to build muscle and support his health.
• Dietitians advise us to get our nutrients from our diets, but supplements can be helpful. 
• Wilson takes well-researched supplements, including creatine, whey protein, caffeine, and vitamin D.

Industry-leading physique coach and former bodybuilder Cliff Wilson shared with Business Insider the seven supplements he takes daily.

It's estimated that more than half of US adults take supplements, according to the American Medical Association, and the market is set to make about $308 billion worldwide by 2028, according to Statista. Nutrition experts recommend getting the nutrients we need from a balanced diet if possible, but each person's requirements are different, and some supplements have been shown to be beneficial.

Wilson, who is based in Chicago, said he's selective about what he uses. For instance, he no longer takes high-caffeine "pre-workout," but is happy to regularly take certain well-researched supplements.

Here's what Wilson uses as someone who works out regularly to build and maintain muscle.

1. Creatine monohydrate

Wilson said he takes five grams of creatine monohydrate daily to help him build muscle and support his cognition and mood.

"It's also relatively cheap," he said.

Creatine is found naturally in foods such as red meat, and it helps the body produce energy for intense activity.

Creatine is well-researched and known to be safe for most adults, which is why it's popular for boosting workout performance and, in turn, muscle growth.

There are some emerging links between creatine and mental health and cognitive benefits, too.

2. Whey protein powder

"There's nothing magical about protein powder and it's not a necessity, but it's a huge convenience factor," Wilson said.

Most Americans get enough protein in their diets, but athletes and active people such as Wilson require more.

"If you are a busy person, it's hard to sit down and consume as much protein as you need during the day. So being able to mix up a shake once or twice a day is quite the luxury," he said.

Eating enough protein helps muscles repair and rebuild after workouts.

3. Caffeine

Wilson counts caffeine in coffee as a supplement that many people forget.

"In responsible doses, caffeine helps with fat loss and can improve performance in the gym, but everyone seems to have their own tolerance," Wilson said.

The health benefits of coffee are well established, but too much caffeine can cause anxiety.

4. Vitamin D

"Effective and cheap, vitamin D supplements help to maintain my energy and hormone levels," Wilson said. "I take a higher dose in winter."

Registered nutritionist Rhiannon Lambert previously told BI that residents of the UK and countries with similar levels of sunlight should supplement with vitamin D, especially in the winter months, to help keep bones, teeth, and muscles healthy.

5. Pre-workout

Wilson said he's stopped taking pre-workout supplements with high quantities of caffeine as they can lead to overtraining.

He looks for ones with a "reasonable dose," meaning one with 200 to 300 milligrams rather than 400 milligrams upwards. The FDA says that 400 milligrams of caffeine a day is a healthy amount, but personal tolerances vary a lot.

6. Fish oil

Wilson said he takes fish oil supplements for the potential heart health benefits.

It's well established that omega-3 fatty acids are good for the heart: They slow the build-up of plaque (which blocks the arteries), lower blood pressure, and reduce triglycerides, a type of fat in the blood. However, research is mixed on whether fish oil supplements provide the same benefits as eating oily fish.

7. Glutamine

Research is mixed on whether glutamine aids muscle growth, but Wilson is more interested in its links to immune function, he said.

Glutamine is an essential amino acid that plays a key role in a range of bodily functions. It's produced by the body and also found in food such as eggs, beef, and tofu.

Potential benefits of glutamine supplements include reducing muscle soreness after workouts, boosting the immune system, and supporting muscle recovery.