How to know whether trying fitness supplements for weight loss and muscle gain is worth it, according to dietitians

• Fitness supplements can give you an edge in the gym when used correctly, experts say.
• To avoid wasting money, pick the right supplements for goals like muscle gain or weight loss.

Fitness supplements like preworkout, protein shakes and more promise to give your gym routine an extra boost — but some can just waste your money instead, according to a sports dietitian.

Get the most bang for your buck by picking the right supplements for your goals and routine, according to Brett Singer, a sports dietitian at Memorial Hermann IRONMAN Sports Medicine Institute who works with the Houston Dynamo.

Singer told Insider that fitness supplements like creatine are extensively researched, generally safe, and have evidence-based benefits for boosting performance and gains in the gym.

However, supplements can be costly and may not be right for everyone — knowing the right timing, dose, and purpose of each product can give you an edge.

"There are many different avenues of success. What may work for me may not be effective or feasible for you. It's about looking at your options and understanding the evidence and limitations," Singer said.

Understand your goals to prioritize the most useful supplements

The first step in getting the most out of a supplement routine is to consider your goals, according to Singer.

Knowing what you hope to achieve helps identify how supplements might help, or if they're worth using, he said.

For instance, if your goal is primarily weight loss, there's little evidence that supplements can burn fat directly, Singer said. However, performance-boosting supplements may help you start or maintain a gym routine to support a healthy weight loss plan.

"Supplements that allow you to work out better and harder can have positive effects in terms of confidence and weight loss," he said.

Always read the label of supplement blends to know what's in a product like pre-workout, and what it does. Common ingredients like caffeine and creatine, are versatile and can aid in both improving performance and changing body composition, according to research.

Others may be more appropriate for specific sports. Nitrate, for instance, may be more useful for endurance athletes, while sodium bicarbonate (otherwise known as baking soda) might be more beneficial for high-intensity workouts, research suggests.

"Not all supplements are beneficial for all athletes," Singer said.

Supplements won't make up for bad habits, so fix your routine first

While supplements may have small benefits regardless of your overall routine, the best way to make the most of them is by dialing in habits like nutrition and sleep first, sports nutritionist Scott Forbes told Insider.

"Things that are really important and have a big impact on performance, I call those 'sledgehammers'. Eating enough, exercising, good nutrition, and sleep," Forbes said. "There are benefits to supplementing without them, but it's not what people should be focused on. Concentrate on getting those in order first."

Sleeping less than seven hours per night, working out too much, and eating too little are common mistakes that prevent muscle gains. Comparatively, the improvements from adding supplements will be much less noticeable than fixing problems with your routine. For instance, chugging a protein shake won't fix your overall diet. Instead, focus on getting plenty of protein from whole food sources, then supplement as needed.

"The gains and benefits are going to be small, so I don't know that it will provide benefits to make up for a poor diet," Singer said.

Make sure you're getting the right dose

Once you've found the right supplement, follow dosing recommendations carefully, according to experts.

"A lot of brands use recognizable supplements, but not enough or not in the best form," Singer said.

Check the amount of each ingredient on the label, since many products contain similar blends and combining them can compound the effect, Singer said.

Supplements that are safe to take in moderation can cause side effects if you get more than the recommended dose, through one or multiple products, can backfire. Too much caffeine, for instance, can cause a range of issues from anxiety and digestive upset, to serious health problems such as rapid heart rate or trouble breathing.

Also be mindful about possible interactions if you're taking other medications.

Time your supplements appropriately

When you take supplements also matters. Caffeine, for instance, only improves performance if taken before a workout, according to evidence.

For other supplements such as creatine, the specific day-to-day timing may not matter, but you need to be consistent with taking them regularly to maximize the benefits, Forbes said.