Another day, another supplement taking over the internet. Sigh.

There’s so many skin care options, and so much information on each, that you’ll give yourself crow’s feet just thinking about it.

If you’ve been cruising around Paleo websites or following the latest beauty advice, you’ve probably seen the word “collagen” thrown around more than once.

Until recently, collagen was a treasured ingredient in anti-aging creams but didn’t play an Oscar-winning role in the Western supplement industry.

But with collagen peptides gaining popularity, it seems time to answer the question: What exactly are collagen peptides? What are they for? And, even more importantly, why should anybody care?

We get under the skin of this increasingly popular beauty supplement.

Before we get into the ins out outs of collagen peptides, it’s good to know what it is. Collagen is a structural protein of which human and animal bodies have loads.Shoulders MD, et al. (2009). Collagen structure and stability.

In fact, it’s pretty much the glue that holds all your bits together. As people age, they produce less collagen.Varani J, et al. (2006). Decreased collagen production in chronologically aged skin.

This causes the skin to lose elasticity, become more wrinkly, and all the other fun stuff that goes along with getting older.Ganceviciene R, et al. (2012). Skin anti-aging strategies.

In theory, adding more collagen to your diet sounds like a great idea. Who doesn’t want to have fewer wrinkles and less joint pain? But do these supplements really make a difference?

It’s not a shock that collagen peptides are a form of collagen — gold star for working that one out. But it’s slightly more surprising to learn that collagen and gelatin are almost exactly the same.

Yep. The new supplement craze sweeping the world off its feet is basically just the stuff you use to make Jell-O shots. Collagen naturally occurs in all animals, and we humble mammals have more of it than any other protein.

Gelatin is just the processed version of this common protein. Fancypants people call gelatin “hydrolyzed collagen.” This is a way less banging name than “Jell-O” but at least clears up its link to collagen.

The high sugar content of Jell-O and its wibbly-wobbly cousins pretty much outweighs the benefits of the gelatin, so don’t start mainlining Jigglers in the name of good health.

The biggest difference between peptides and gelatin is how they dissolve. Collagen peptide supplements have a low molecular weight, so they can dissolve in hot or cold water and are supposedly easier to digest.Sibilla S, et al. (2015). An overview of the beneficial effects of hydrolysed collagen as a nutraceutical on skin properties: Scientific background and clinical studies.

Gelatin only dissolves in hot water (something all you Jell-O shot veterans already know). Eating undissolved gelatin can be a little harsh on the stomach. Also, gross.

Since a supplement that dissolves in water of any temperature is much easier to use, collagen peptides have become the life of the skin party.

Plus, a collagen peptide-infused smoothie sounds way cooler than a Jell-O juice when you ask at the gym juice bar.

If you look at enough websites, you’d think collagen was some kind of miracle powder that cures everything except cancer and herpes. Most supplements have evangelical enthusiasts, but, more often than not, it’s too good to be true. So what can collagen peptides really do for you?

Well, it is a good source of protein. In one scoop of peptide powder, you typically get 10 grams of protein and 40 calories, which is not a bad trade-off.

Now, if you’re a vegetarian, watch out. Manufacturers derive most collagen products from animal bones or fish scales. However, we looked at how a vegan diet can improve your skin health anyway.

When it comes to skin, some evidence suggests that collagen supplements really do help. One study found that skin hydration and collagen density increased after 8 weeks of taking oral collagen.Asserin J, et al. (2015). The effect of oral collagen peptide supplementation on skin moisture and the dermal collagen network: Evidence from an ex vivo model and randomized, placebo-controlled clinical trials.

The researchers found, in all their sciencey wisdom, that collagen may be a helpful tool in decreasing the skin’s signs of aging. It’s only one study, but it provides a little hope for collagen peptide enthusiasts all the same.

Check out our guide to protein supplements.

The other collagen claims are a little harder to nail down. The studies out there have conflicting results. Here are a few intances in which collagen might really play a role in keeping your skin on fleek.

If you have brittle or ever-breaking nails, there’s some evidence to suggest collagen peptides could get you the manicure of your dreams. A 2019 review suggests changing the amount of collagen peptides in the diet can support different health goals, such as improved nail health.Paul C, et al. (2019). Significant amounts of functional collagen peptides can be incorporated in the diet while maintaining indispensable amino acid balance.

A German/Brazilian study found that participants taking supplements for 24 weeks had a 12 percent increase in nail growth and a 42 percent decrease in the number of broken nails.Hexsel D, et al. (2017). Oral supplementation with specific bioactive collagen peptides improves nail growth and reduces symptoms of brittle nails.

Weak nails might be a sign of an underlying health problem. Learn more.

Before you start chugging collagen wholesale, know that this was a non-blind study with 25 participants and no placebo group. Basically, the study doesn’t mean much.

Sorry to rain Jell-O on your supplement parade, but science still doesn’t back a strong link between collagen and nail health.

When it comes to joint pain, evidence suggests that collagen supplements might help your creaky bones feel a little better.

A study from Penn State University found that athletes had significantly less joint pain during rest and movement after taking collagen peptides.Clark KL, et al. (2008). 24-Week study on the use of collagen hydrolysate as a dietary supplement in athletes with activity-related joint pain.

So collagen could have the capability to ease pain, inflammation, and reduce joint damage on the whole.

Sadly, we can’t officially draw any conclusions from one 97-person study, but it shows how collagen peptides may be of service to the world of joint pain. In the meantime, if your knees are giving you hassle, these exercises may help.

There are claims that collagen can help with digestion and fix “leaky gut.” The debate continues around whether leaky gut phenomenon is even real. Many gastrointestinal experts deny its existence entirely.

If your health professional diagnosed you with leaky gut, feel free to take their advice. Either way, there isn’t much evidence to suggest that collagen would help with this or any other gastro problems.

Here’s a range of stupid things dermatologists have heard recommended to patients. Don’t try these at home. Or anywhere.

Lastly, collagen won’t give you a one-way ticket on the Snoozetown express. Many holistic sites claim that collagen peptide supplements help you fall asleep faster and sleep deeper through the night.

Unfortunately, there’s really nothing reliable out there to suggest that it will stamp your visa for the land of nod. Though, sure, if your joints are less achy because of supplements, or if you’re so filled with glee over your collagen-induced wrinkle-free skin, you might sleep pretty well.

But don’t turn to peptides to knock you out at night. Instead, we explore 31 alternatives that might really help you get to sleep.

I added collagen peptides to my morning smoothie for a month, so I could have some firsthand experience with the collagen craze.

Was my skin transformed? Were my nails healthy and long? Did my joints feel 10 years younger? Can I harness the power of the sun and conquer planets now?

No. No to all of it.

Now, I didn’t notice any worrying side effects. On the flipside, I also noticed absolutely zero difference in my skin, hair, nails, joints, sleep pattern, or cellulite.

(A lot of folks are hawking it as an anti-cellulite cure, but… there’s no real evidence. Don’t believe the snake-oil hype.)

Of course, I only tried it for a month, and I’m only one person. Its lack of effects on my skin may not mean it won’t help yours.

Will I still take collagen supplements? Weirdly, yes! I don’t get a lot of protein, and I don’t like the taste of most protein powders. But the collagen blended easily into smoothies without adding any texture or flavor whatsoever.

Even in thin juices, I could never tell it was there. So, for that alone, I’m willing to keep up my collagen intake.

As far as supplements go, collagen peptides seem pretty promising. Though the science to prove its efficacy is in the early stages, there are good signs pointing toward increases in skin and joint health when you add collagen to the mix.

Will it change everything overnight? Of course not.

But if you’re looking for an easy protein powder that might do some other good things for your body along the way, collagen peptides are worth a try.

Amber Petty is a freelance writer in Los Angeles who writes for Bustle, Elite Daily, Thrillist, and a lot of other random sites. If you like easy crafts and Simpsons gifs, check out her blog Half-Assed Crafts.