Instagram has taken over the world. It can be way for people to express their passions, to have their voices heard, or to just filter their countless selfies. The video and photo sharing app has become increasingly popular over the years and has an estimated 400 million monthly active users today.

It has been a great tool for people to network, gain exposure, and even make a living. And it's been good for many companies, too, because they understand that advertising through social media accounts with large followings can be a strategic and great way to market their goods and services. In fact, some users even get paid thousands of dollars to promote or advertise for a company.

Fashion, beauty, health, and fitness pages ­­— some of the pages with the largest followings — use popular personal accounts, such as those of celebrities and bloggers, to advertise. Unfortunately, just because a popular person promotes something on Instagram doesn’t mean that it’s safe or healthy to use.

In 2015, for example, Kim Kardashian used the platform to promote an anti-nausea medicine called Diclegis. She subsequently received a warning from the Food and Drug Administration (FDA) saying that her post violated federal drug promotion regulations. The administration scrutinizes such prescription medications more rigorously than it does non-prescription products, though, so consumers can’t always count on them for protection.

Advertising like this happens often across the internet, especially on Instagram. Waist trainers, detox teas, orthodontics, and hair vitamins have all become increasingly popular, but they come with plenty of hazards, too.

Fit Teas

These laxative teas are advertised to help you lose weight and gain a flatter stomach. The problem is, they only help people lose water weight. Ads for fit teas, as they are known on the internet, like SkinnyMe Tea and TinyTea Teatox Detox can be very misleading and expensive.

“They have all these claims that you’ll lose weight, but it’s mostly water weight and not fat,” Dr. Gina Sam, a gastroenterologist and the director of Mount Sinai Gastrointestinal and Motility Center, told Medical Daily.

She suggested that people drinking the teas use them sparingly. “If you drink it too much or too often, it can cause an electrolyte abnormality, which is an altered loss of potassium or magnesium,” Sam said. “They can also cause problems with the renal system and the heart.” Electrolyte anomalies can lead to cardiac arrest and be life-threatening.

Senna, the main laxative in many of these teas, is derived from the dried pods of the cassia tree. It’s generally safe, but if used for a prolonged period of time it can damage the liver. Your body can also become dependent on senna, Sam said. “Your gastrointestinal tract is already designed to clear out toxins via the liver and kidneys so when you keep drinking these teas your body gets more and more dependent on them.”

Waist Trainer

This girdle-like product is the descendant of the corset, remade for modern times but for basically the same purpose. Waist trainers are used when working out to supposedly help women lose weight while still maintaining their curves.

Sam says the only thing that waist trainers will help women lose is water weight, and it can be dangerous to use one when working out. “It puts pressure on the stomach and colon, and you can get shortness of breath in the lungs and diaphragm,” she said.

The trainer can also impede blood flow. “It compresses the abdomen so much that I’ve actually had parents come in for hemorrhoids after using a waist trainer,” Lindsey A. Bordone, a dermatologist at Columbia University, told Medical Daily.

Home Orthodontics

A perfectly straight Hollywood smile can be expensive to engineer. Some companies, like Smile Direct Club, claim they can improve and straighten your teeth from the comfort of your own home while saving you money.

However, Dr. Kyle Stanley, a practicing dentist at Beverly Hills Dentist and a faculty member at the University of Southern California Ostrow School of Dentistry, told Medical Daily that this can be very dangerous.

“There is not a thorough comprehensive exam done by a dentist or orthodontist prior to treatment. This would include a full set of X-rays to look for infection or cavities, gum measurements to look for gum disease and bone loss, and oral cancer screening,” Stanley said.

He also said that before any orthodontic treatment takes places, existing dental conditions such as cavities or faulty dental implants need to be taken care of. “Improper planning can result in losing teeth due to inadequate support of the bony architecture that houses the teeth,” he said. As for the low cost: “I recommend patients seriously consider how much they value their health and safety. There are too many catastrophic risks by taking something like this lightly and putting your safety in the hands of someone with very little training and ability to intercept a problem during treatment.”

In some cases, the teeth can move too fast or too far, which can cause them to fall out or lead to gum disease. If the at-home dentistry does go awry, it could end up costing more than if you were to see an orthodontist in person.

Hair Growth Vitamins

The word “vitamin” may make these seem harmless when, in fact, these products can be loaded with untested ingredients.

Since supplements aren’t regulated by the FDA like prescription medications, companies selling them don’t have to jump through the same hoops as makers of prescription pharmaceuticals.

“Many of these vitamin companies don’t have a long and reputable history — they just started recently and don’t have any real testing. You’re kind of taking a risk when you take them,” said Bordone.

She adds that these products are basically a multivitamin loaded with sugar. “This is the case where picking a brand-name company is probably better than taking something that just showed up on the market. The larger companies have probably had testing done in scrutiny of their products,” she said.

All of these products combined have over a million followers on Instagram. But, just because something is popular or has celebrity backing doesn’t mean that it’s safe. Before starting any supplement regimen or trying anything that could be potentially harmful, it’s wise to speak with a health professional or specialist.