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Kidney-Disease

Collagen

What Is Collagen?

Collagen is the most abundant protein in your body. It’s in your skin, bones, cartilage, tendons, and gut lining. Your body makes it naturally, but production drops as you age.

Collagen supplements come in a few forms. Hydrolyzed collagen peptides (Types I and III) are the most popular. They dissolve in liquids and your body absorbs them easily. UC-II (undenatured type II collagen) is a different approach. It works through your immune system at much lower doses.

Creatine

What Is Creatine?

Creatine is a natural compound your body makes from amino acids. Your muscles store it as phosphocreatine and use it for quick energy during intense efforts like lifting weights or sprinting.

You get some creatine from meat and fish. But supplementing with creatine monohydrate raises your muscle stores about 20-40% above what food alone provides.

It’s one of the most studied supplements in history. We’re talking about hundreds of randomized controlled trials. The data on creatine is stronger than almost any other supplement you can buy.

Magnesium

What Is Magnesium?

Magnesium is an essential mineral your body needs for over 300 enzyme reactions. It’s involved in muscle function, nerve signaling, blood pressure regulation, and energy production.

About 50% of Americans don’t get enough magnesium from their diet. That’s why it’s one of the most popular supplements on the market. But popularity doesn’t equal proof.

We analyzed 8 meta-analyses and systematic reviews covering 120+ individual studies. Here’s what the data actually shows for magnesium’s biggest claims.

Vitamin D

What Is Vitamin D?

Vitamin D is a fat-soluble vitamin your body makes when sunlight hits your skin. It’s also found in fatty fish, egg yolks, and fortified foods. But most people don’t get enough from food and sun alone.

About 42% of American adults are deficient. That number jumps higher if you have dark skin, live far from the equator, or spend most of your time indoors.

You’ll see vitamin D marketed for everything from bone health to cancer prevention to muscle growth. Some of those claims hold up. Most depend heavily on whether you’re deficient or not.

Zinc

What Is Zinc?

Zinc is an essential mineral your body needs for over 300 enzyme reactions. It plays a big role in immune function, wound healing, and cell division. Your body doesn’t store it, so you need a steady supply from food or supplements.

You’ll see zinc marketed for everything from fighting colds to boosting testosterone to clearing acne. Some of these claims have solid research behind them. Others don’t.

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