Taking dietary supplements might help you reach health goals, like getting the nutrients you need, getting better sleep, or supporting your bone health. But even if a supplement helps in the way you expect, it can still come with side effects. Some supplements might not make any noticeable difference at all.

On MyObesityTeam, some members wonder how certain supplements might influence their weight. “Does anyone take a supplement that has helped lose weight?” asked one member.

A few supplements claim to help with weight loss, but some people living with obesity might worry that certain supplements or vitamins cause weight gain instead. Read on to discover what you should know.

What Are Vitamins and Supplements?

Supplements are substances you can take along with your regular diet to add nutrients you need for overall health or to help reach a goal, like better sleep. You can take them in different ways, such as in capsule form, powders you add to drinks, or chewable gummies.

The United States Food and Drug Administration (FDA) estimates that there are over 100,000 supplements available on the market today. The FDA regulates supplements as a type of food, but doesn’t review their safety or effectiveness for health claims before they’re sold. Many supplements contain vitamins and minerals.

Vitamins

Vitamins are substances your body needs but doesn’t produce. You get most of the vitamins you need from foods and beverages if you eat a balanced diet.

Minerals

Other supplements contain minerals, which your body also needs in very small amounts to function normally. You might be familiar with some of the minerals your body uses, such as calcium, magnesium, iron, and zinc.

How Supplements Affect Weight

Generally, supplements don’t directly cause weight gain. However, some supplements might indirectly cause an increase or decrease in weight in a few ways.

Supplements and Weight Gain

Certain vitamins and minerals might increase your weight by helping you build more muscle. Some people take supplements so they can build muscle more easily from working out. Since muscle is denser than fat, you might gain weight while losing fat if you’re building muscle at the same time.

Supplements may also be linked to weight gain because they can make your body hold onto water. In addition, some supplements might make you hungrier, leading to eating more calories. However, some of these studies are based on animals, not humans.

Some supplements have added sugar or calories, such as supplement drinks. These may cause weight gain if they add more calories than you need.

Supplements and Weight Loss

Weight loss is a potential side effect of some supplements. Certain supplements might cause weight loss by lowering your appetite or helping you feel full. Some may also help you burn body fat, but the research is inconsistent and depends on your overall diet and metabolism. Some supplements may also block the absorption of some types of carbohydrates (carbs) from your diet.

Supplements That Might Contribute to Weight Gain

Certain vitamins and minerals might contribute to weight gain or seemingly slow down weight loss. However, these results show slight changes in metabolism, or how your body uses energy. When it comes to weight gain or weight loss, the quality and amount of food you eat, as well as your activity level and healthy lifestyle, matter most.

Creatine

Creatine is a substance your body uses to contract your muscles, especially during exercise. You get creatine from high-protein foods like red meat and milk, but many people take creatine supplements to give them more strength and energy during workouts. Doing this might help them build more muscle, which can cause an increase in body weight. Research has found a link between weight gain and creatine supplement use. But doctors believe most of the weight gain comes from increased water retention.

Niacin

The supplement niacin, also called vitamin B3, plays several roles in your body, including supporting your heart health and metabolism.

High doses of niacin supplements can cause hyperglycemia (high blood sugar) as a side effect. This may have an indirect link to weight gain because high blood sugar over time can be stored as extra fat.

Zinc

Zinc is a mineral that plays an important role in your metabolism and appetite.

Some research suggests that taking zinc supplements can contribute to weight gain in people undergoing hemodialysis, used for kidney failure. It might contribute to weight gain by speeding up digestion, which may lead some people to eat more food and take in more calories.

While some other research findings suggest there might be a link between zinc supplementation and weight loss in people living with obesity, doctors aren’t certain about the connection. More research is needed to explore the impact of zinc on body weight.

Talk to Your Doctor

Talk to your healthcare provider before taking any new supplements, even if a supplement seems like it could help you reach a health goal. Supplements don’t always live up to the claims on their labels, like “weight loss” or “energy-boosting.”

Some supplements can cause side effects, while others may interact with medications you already take. Others might be risky to take for people living with certain medical conditions or chronic diseases. Your doctor can help you decide if a supplement might benefit you, if it’s safe to take, and how much you should use.

Join the Conversation

On MyObesityTeam, people share their experiences with obesity, get advice, and find support from others who understand.

Have you noticed weight changes while taking supplements? Let others know in the comments below.