Its usually smart to avoid foods that have long, complicated words on their ingredient labels that induce you scratch your head. If the ingredients sound like someone induced them up, opportunities are they didin a chemistry lab. So its not surprising that health professionals have warned against energy beverage intake pretty much since they became popular. Reading the words on a can, you start to wonder: Does anyone actually know whats in this?

The answer is yes, and also not really. We know caffeine and sugar, both of which are plentiful in energy beverages. The other ingredients, though, arent quite as ubiquitous in our daily dietsunless you frequent GNC. When it comes to security, health experts are weary about both the amount of caffeine packed into a single can, and how all the substances may interact.

Related : This Is What Sex Looks Like From Inside The Vagina, Because Science

Energy drinks caffeine content differs a lot, Sheri Zidenberg-Cherr, Ph.D ., a nutrition expert in the UC Davis department of nutrition, told SELF.

Theyre considered supplements and not a food product, so labeling requirements are quite lax, and the ones that do label caffeine content may not make it very legible. When it comes to the other, more unknown ingredients, Zidenberg-Cherr has pointed out that even if one substance is proven safe on its own, that may change when its combined with other things.

The problem with these drinks is there are a lot of ingredients being added to them, some that have been used before in this way and others that have not, and its the mixture thats the concern, Zidenberg-Cherr said.

So whats even in that mixture? Here are some of the most common energy drink ingredients, and where they rate on usefulness and safety.

1. Ginseng

Used most commonly in Chinese medicine, ginseng is an herb that been used traditionally to treat numerous ailments. Its generally thought to boost immunity and be enhanced overall healthyouve likely ensure it added to green tea and other herbal remedies. Research doesnt conclusively back up these claims, but short-term employ is also considered safe. The concern, though, is that it may compound caffeines impact and increase side effects like increased heart rate, Zidenberg-Cherr said.

Related: 6 Symptoms Of Acid Reflux You Should Not Dismiss

2. Taurine

This is an amino acid that we find in protein, meat, fish, breast milk, Zidenberg-Cherr explains. It helps us maintain neurological function and govern fluid levels. There are some claims that taking a taurine supplement can improve athletic performance, but not a lot of data exists on its efficacy or its safety as either a supplement or energy drink ingredient.

The concern has been that when its mixed with high amounts of caffeine, there could be impacts on the heart, Zidenberg-Cherr said.

One 2014 review found that taurine seems to counteract some of caffeines cardiovascular consequences rather than compound them.

Related: Jillian Michaels 7 Commandments For Lasting Weight Loss

3. Guarana

Guarana is an herb thats often used as a stimulant in teas, either added or naturally occuring. Its major component is caffeine.

It has been associated with increased energy and enhancement of physical performance, Zidenberg-Cherr said.

Its generally recognized as safe( GRAS ), but Zidenberg-Cherr notes that no one really knows if its still just as safe when compounded with other high-caffeine ingredients.

Related: You Can Have Adult ADHD And Not Know It

4. Ginko biloba

This is another herb, added to supposedly increase alertness.

Theres been a lot of studies looking at it in terms of mental function and mental alertness, Zidenberg-Cherr told. But there is not very consistent information on it.

Its been used medicinally for thousands of years, according to the Mayo Clinic, and research supports its use for some medical conditions including dementia, nervousnes, and schizophrenia. For other uses, evidence is lack or mixed.

It might also depend on what other drugs someone is taking, Zidenberg-Cherr added.

Oftentimes, we view herbal ingredients as safe because theyre natural, but if youre taking other drugs, they could interact with some of these herbs.

Related: How Much Protein Do You Genuinely Need ?

5. Carnitine

Our bodies naturally render carnitine, a substance thats used to turn fat into energy. You can also buy it as a supplement, and it claims to boost exercise performance.

Theres not much data to encourage its use, Zidenberg-Cherr told. Theres no evidence that taking it is going to alter anything, and theres not a lot of information on its safety as a supplement.

Some surveys suggest carnitine may be promising in treating various health problems, like certain heart conditions, kidney cancer, and hyperthyroidism, but in all cases, more research needs to be done and supplements should not be taken without a doctors supervision.

Related: How To Tell If Youre Legit Addicted To Food( Or Just Really, Ridiculously Into Eating It )

6. Green coffee extract

You may have heard of green coffee bean pills from that lawsuit the FTC won against a company selling them as a magical weight loss medication, with totally falsified research to back up their asserts. Dr. Oz got some fairly hefty backlash, too, after promoting the bogus pills as a secret weight-loss weapon. Zidenberg-Cherr told green coffee extract, which is often listed in energy beverages and especially those claiming to be all-natural, is just another form of caffeine.

People look at it supposing its natural so its better, Zidenberg-Cherr told, but all caffeine works the same way in your body. And no, its not the sorcery weight-loss wonder our society has been searching for.

Read more: