Product Description
Hard training blocks leave you more fatigued than a single night of rest can fix. Part of that comes down to oxidative stress building up faster than your body can neutralize it, and neutralizing it depends on one raw material your body can only produce so much of on its own.
Designs for Sport's NAC 900 is built to hand your cells more of that raw material directly, delivering 900 mg of N-acetyl-L-cysteine in a single daily capsule.
Fuels Your Body's Own Antioxidant Defense - NAC 900 supplies the cysteine your body needs to keep producing glutathione, the antioxidant your cells rely on most, so your natural defenses keep pace with training instead of falling behind.
Supports Performance When Training Gets Hard - By feeding the same pathway that keeps oxidative stress in check, NAC 900 supports exercise performance during your hardest training blocks, not only the easy ones.
Backs Recovery Between Sessions - The same antioxidant support that helps during a workout keeps working afterward, giving your body what it needs to recover between one hard session and the next.
Glutathione is built from three amino acids, glycine, glutamine, and cysteine, and cysteine is the one your body runs short of first. Taking glutathione itself as a supplement runs into a problem, since the tripeptide breaks apart in your gut before much of it reaches your cells. NAC sidesteps that. It's a small, stable form of cysteine that absorbs efficiently and hands your cells the exact building block they need to keep glutathione production running, the same antioxidant system that also backs your respiratory and immune function during heavy training.
How to Use NAC 900
Dose: Take one capsule daily.
- Gluten free
Supplement Facts
120 Servings
Serving Size: 1 capsule
Serving Per Container: 120
| Amount Per Serving | ||
|---|---|---|
| % Daily Value* | ||
| N-Acetyl-L-Cysteine 900mg | ** | |
* Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.
** Daily Value (DV) not established
We want you to love the nutrition you purchase from The Feed. We also know that sports nutrition is personal - a flavor, texture, supplement, or fueling product that works perfectly for one athlete may simply not be the right fit for another.
That’s why we offer our Always Happy Promise.
If you try a nutrition or consumable product and you’re not satisfied with it, let us know within 30 days of delivery and our Athlete Experience team will work to make it right.
Designs for Sport NAC 900 FAQ's
Everything you need to know about Designs for Sport NAC 900.



Take one capsule daily, with or without food. Since it's feeding an ongoing process — glutathione production — consistency matters more than exact timing, so pick a time you'll stick with every day.
It hands your cells cysteine, the raw material they need to keep making glutathione, your body's main antioxidant, so your defenses don't fall behind during hard blocks. That same support carries into recovery, helping you bounce back faster between sessions.
Glutathione is a tripeptide that breaks apart in your gut before much of it reaches your cells. NAC is a small, stable form of cysteine that absorbs efficiently and gives your cells the exact building block they need to keep glutathione production running.
Glutathione is your body's most powerful antioxidant, built from three amino acids — cysteine is the one you run short of first. It's what keeps oxidative stress from hard training in check, backing performance, recovery, and your respiratory and immune function.
Yes — NAC works upstream of things like electrolytes, protein, or anti-inflammatory support, since it's replenishing the raw material behind your own antioxidant system rather than acting as a direct antioxidant itself. That means it layers cleanly into whatever recovery stack you're already running.