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⏳ Unlock steady energy & calm skin with every prolonged-release tablet!
21st Century Niacinamide 500mg Prolonged Release Tablets deliver a clean, vegan-friendly source of vitamin B3 designed for slow nutrient release. This formula supports energy metabolism, skin health, and nervous system function without the flushing effect of traditional niacin. Manufactured under strict quality standards, it contains no artificial additives or common allergens, making it a trusted choice for professionals seeking sustained wellness and customizable dosing.


| ASIN | B004SCKMQS |
| ASIN | B004SCKMQS |
| Age Range Description | Adult |
| Allergen Information | Gluten Free |
| Best Sellers Rank | #7,891 in Health & Household ( See Top 100 in Health & Household ) #10 in Vitamin B3 (Niacin) Supplements #887 in Sales & Deals |
| Brand Name | 21st Century |
| Color | No Color |
| Customer Reviews | 4.6 4.6 out of 5 stars (5,346) |
| Date First Available | February 3, 2010 |
| Diet Type | Vegan |
| Dosage Form | Tablet |
| Flavor | Unflavored |
| Global Trade Identification Number | 00740985225509 |
| Is Discontinued By Manufacturer | No |
| Item Dimensions | 2 x 3 x 4 inches |
| Item Form | Tablet |
| Item Weight | 500 Milligrams |
| Item model number | 22550 |
| Manufacturer | 21st Century |
| Manufacturer | 21st Century |
| Model Name | av2023-21st Century-mg prolonged release tablets-5f0674d8 |
| Number of Items | 1 |
| Primary Supplement Type | Vitamin-b |
| Product Benefits | Helps convert food into energy and helps maintain skin, digestive and nervous systems |
| Product Dimensions | 2 x 3 x 4 inches; 0.02 ounces |
| Special Ingredients | Gluten Free |
| Specific Uses For Product | Digestive,Skin,Energy |
| UPC | 740985225509 |
| Unit Count | 110 Count |
H**R
time-release Niacinamie + time-release melatonin... Great sleep FINALLY!
So, wow. Fellow strugglers of proper sleep: perhaps you got to here after learning about the "Healthy Sleep Formula" created by Steve Gibson, as I did. If not, and sleep is an issue for you, I highly recommend you google "Healthy sleep formula" to get to the page on grc .com. That guy has a HUGE following. So much so that when he developed his version 2.0 of the sleep formula and recommend a specific brand of Niacinamide, it sold out everywhere. I knew right then that there must be something to this formula of his. Then he popped back with an update stating that this brand was officially recommended after it had been tested out. I would have never thought that Niacinamide (the amide of nicotinic acid (vitamin B3 / niacin)) + melatonin could be such a magic sleep cocktail. And trust me, at this point I have tried a lot of different supplements. I suffer from the kind of insomnia where you can easily go to sleep, but not remain asleep (sleep-maintaining insomnia disorder)... tossing and turning, rarely getting into deep sleep/REM and waking up everyday feeling pretty exhausted. What a waste of time, honestly. I have been on a long road of finding ways to improve this issue through healthy means, trying my best to avoid actual sleeping pills. Things would work for a bit... then no longer be effective and it would be this endless chase for the next sleep fix. But this formula offered me something new: a combination of 2 time-release pills taken together. It addressed my exact needs. And I am here to say, it works. It WORKS LONG-TERM. I have been doing this formula of time-release Nicinamide and time-release melatonin for several weeks now and its amazing the energy I have now. Many days I wake up about 10-15 minutes before my scheduled alarm for work, have much more vivid dreams, have no issue getting out of bed and out the door, actually feel like going to the gym on my lunch break instead of taking a car nap...it's put me on a great healthy schedule overall and feeling top of my game. I actually look forward to bedtime now. If you do Steve's formula, you have to figure out what is best for you. I will state that I am not a sensitive person and typically need higher dosages of things. In my experimenting I have found that 1250mg of Niacinamide + the 1mg melatonin works best for me to sleep through the night without crossing over into groggy-ville. It is one reason why I like this brand being a lower dosage of 500mg, so I can easily up 1/2 and full dosages cutting the pills. It was very much a goldilocks situation... 1 is too little... 2 is too little... 3 IS TOO MUCH IM IN A HAZE... 2.5 is just right :D So thats my story of Niacinamide and how it's solved my sleep-maintaining insomnia. Pretty amazing, I can't fully believe it yet. Just in case you are wondering the breadcrumb trail of how I got here... it went: friend told me about GABA... and combining with taurine to be more effective. I researched GABA and stumbled on a "sleep hacking through biochemistry" blog... read about all these things to help get you into sleep faster and more lasting, and replacing 5-HTP with tryptophan (but it mentioning a high tryptophan diet might not be healthy so being careful not to use constantly)...blah blah read some reviews on the tryptophan I was getting and mentioning Steve Gibson's healthy sleep formula. His 1st generation formula used a handful of all those aforementioned things till he developed the 2nd gen one. Glad I jumped on board after that point! Its cheap and super effective.
M**C
Great Quality & Pricing
Bought these as they are the only ones I could find that were time-released, as your body can't absorb that much at one time, it will just flush out, so these are perfect for me and my husbands needs. You have to take them with a meal and it is very wise not to drink alcohol with this product as it will basically nullify the effectiveness of the Niacinamide. Good stuff, quality, great pricing on the two-pack. Will purchase again in the future
S**N
Wow!
I noticed dramatic improvement with the healing in my skin. Sign me up for life!
T**B
Unfortunately includes calcium
This is a quality product however, it has calcium in it. This can be problematic for people who avoid supplementing with calcium who are prone to atherosclerosis or calcification in arteries. Although it is clearly on the label, it seems unnecessary for a product also labeled as support for "energy and circulatory."
D**I
Great Daily Supplement/21st Niacinamide Flush released 500mg.
A good buy for daily supplement or weekly. Color non stomach upset and taste equivalent to swallowing. Easy to administer and won't interrupt energy level.
S**N
A Good choice for Niacinamide
For the past 6-10 years this has been the most economical way to buy Niacinamide. The 500mg dosage is easier to deal with if one wants to vary their dosage. It seems to work, but after the first few days I don't feel any different before and after taking them. I started taking them as a part of Gibson Research / Steve Gibson's "Healthy Sleep Formula".
S**T
Very very very good.
The first day I took this I got a lot of energy for about an hour then I seemed to have sort of "crashed". But that was only the first day. Since then I've taken it every morning and it's been incredible. I have more energy and my joints don't hurt. I'd say I'm even in a better mood because of it. I highly recommend it.
A**R
Works well, don’t take more though!
So, I have little doubt as to the potency if these. It seems the max dose of Niacin is 1,000mg, or two of these pills. Well. I took two. And hypervitamintosis is real. Usually this means you just excrete the excess, usually through urine. Not so with Naicin! No Sir! I was “asleep” when I, so I have been told, was acting like a toddler, blinking rapidly and smacking my rear end. Because too much niacin can cause what are called Niacin Night Terrors. I woke up to three paramedics making sure I was alright and confusion all around. So, take only the recommended dose, take it as soon as you wake up!
S**R
النياسين مهم جدا للدورة الدموية
I**S
This is really improved my skin and hair, of course I am on healthy diet and I’m taking other vitamins and minerals. my body absorbs it easily no stomach irritation or smell. My hair was good but after this vitamin now I rarely see one two hairs falling per day. I’m sensitive and not any supplement fits me but my body didn’t show any allergic reaction. And delivery was fast.
S**S
I am giving it 5 star because there is no averse reaction, but not sure it improves skin condition much
T**Y
Great product.
M**R
Em ótimo estado
Trustpilot
5 days ago
3 weeks ago