If weight loss was as easy as popping a supplement, we’d all be thin as reeds. We could settle on the couch and watch Netflix, while the supplement did all the work.

In reality, slimming down isn’t that simple. Learn what the experts have to say about vitamins and weight loss.

When you scan the supplement shelves at your local drugstore, you might see weight loss touted as a benefit of many products. For example, some people claim that vitamin B-12, calcium, omega-3 fatty acids, and green tea supplements can help you lose weight.

The purported benefits range from “revving up your metabolism” and “flipping a switch in your body” to “signaling your cells to burn fat.”

However, scientists have found little evidence to bolster these weight loss claims.

Whether you pop it in pill form or get a pricey injection, don’t expect a vitamin B-12 supplement to boost your metabolism and burn away fat. According to the Mayo Clinic, there’s no evidence that it will promote weight loss.

Your body does need vitamin B-12 to support the function of your nerves and blood cells, and to produce DNA. To get your daily dose, as recommended by the Office of Dietary Supplements (ODS), include foods that contain vitamin B-12 in your diet.

For example, eat fortified whole-grain cereal for breakfast, a tuna salad sandwich for lunch, and an egg frittata for dinner. Beef liver and clams are also rich sources of this vitamin.

You may need more B-12 if you’re a heavy drinker, have a history of anemia, are a strict vegetarian, or have had bariatric surgery.

Your body needs vitamin D to absorb calcium and keep your bones strong. But experts aren’t convinced that it will help you lose weight.

One study published in the American Journal of Clinical Nutrition found that overweight postmenopausal women who took vitamin D supplements and achieved healthy or “replete” levels of this nutrient lost more weight than women who didn’t reach these levels.

But more research is needed to test these results and learn how vitamin D supplements might affect other people who are overweight.

Until we know more, you can probably get your ODS-recommended dose of vitamin D by reaching for low-fat dairy products, juices, and cereals that have been fortified with this nutrient.

Fatty fish, such as herring, mackerel, and tuna, also deliver modest doses of vitamin D. Your body produces it when you expose your skin to sunlight.

Consider taking regular walks around your neighborhood to get some sunlight and exercise too. But remember, too much sun exposure can raise your risk of sunburn and skin cancer.

Some studies suggest that omega-3 fatty acids support weight loss — but it’s too soon to draw conclusions, warns the Mayo Clinic.

Even so, omega-3 fatty acids are a great addition to your diet. According to the American Heart Association, they may protect your heart and blood vessels from damage and disease. Salmon, mackerel, herring, lake trout, sardines, and tuna are rich sources of this nutrient.

Consider eating these fish a couple times a week, as part of your healthy eating plan. Try grilling, broiling, or baking, rather than frying them.

Will calcium supplements help you lose weight? Most evidence points to “no.” Some proponents claim that calcium increases the breakdown of fat in your cells. Others suggest that it may interfere with your body’s ability to absorb fat from the food you eat.

But according to the ODS, most clinical trials have found no link between calcium consumption and weight loss.

Your body does need calcium to support the health of your bones, muscles, nerves, and blood vessels.

To meet the ODS-recommended target, eat calcium-rich foods, such as low-fat dairy products, dark leafy greens, and tofu. These foods are low in fat but high in nutrients, making them a smart addition to your weight-loss strategy.

As tempting as it may be to curl up with a good book and cup of green tea — or green tea supplements — a brisk walk or bike ride will do more to melt the fat from your middle.

Green tea contains antioxidants that might help protect your heart. But according to research reported in the Cochrane Database of Systematic Reviews, the weight-loss-promoting potential of green tea supplements seems to be small and statistically nonsignificant.

Shelling out money for vitamins or other supplements that claim to aid weight loss usually reduces the size of your wallet, rather than your waistline.

Rather than buying these products, consider investing in a gym membership, a new set of hiking boots, or a set of gardening tools. Gardening is good exercise. You can burn calories while planting, weeding, and watering a plot full of nutrient-rich veggies.

When mealtime arrives, serve your homegrown bounty alongside lean protein sources and whole grains. Exercising more and eating foods that are low in calories but rich in nutrients is a great way to achieve your weight loss goals.