How it works
Nitric oxide (NO) is a small molecule that plays a big role in the body. It helps relax and widen blood vessels, which improves blood flow and lowers blood pressure. This action is important for heart health and overall circulation. Nitric oxide is produced in the body from the amino acid arginine. When there is a need for increased blood flow, such as during exercise or in response to injury, specific cells release nitric oxide. This molecule then signals the surrounding muscle cells to relax, allowing more blood to pass through. In addition to helping with circulation, nitric oxide also has a role in the immune system. It can help fight off infections and support the body's defense mechanisms. Overall, nitric oxide is essential for maintaining healthy blood flow, regulating blood pressure, and supporting the immune response.
Customer reviews
Discover what our clients think about our service
“I started taking CircO2 in the mornings, and I’ve noticed I feel more awake and steady throughout the day. It’s become part of my daily routine now.”
Brian Moten
“I’ve been using CircO2 for a little over two weeks. I feel more focused and present at work, especially during long meetings.”
Robert M.
★★★★★
★★★★
★★★★
“I love that it’s natural and easy to take. I feel more awake and clearer mentally, especially during busy workdays.”
★★★★★
Hannah W.
“I’m not expecting miracles from supplements — just gentle support — and CircO2 delivers exactly that. I feel more balanced during the day.”
Michael F.
1566 Reviews | 3.8 Average Rating | 74% Recommend This Supplement
Try CircO2 Risk-Free with Our 90-Day Guarantee
We want you to feel completely confident trying CircO2, which is why your order is protected with our “Down to the Last Lozenge” satisfaction guarantee.
If for any reason you’re not fully satisfied, simply return the box — even if it’s empty — within 90 days, and you’ll receive a full refund of the purchase price.
You can choose any quantity that’s right for you, but most customers prefer to start with 3 boxes, so they have a steady supply and can take advantage of the savings. We’ll also cover the cost of shipping.
With nearly 90 days to try CircO2 completely risk-free, you have nothing to lose and plenty of benefits to explore. Once you experience how CircO2 fits into your daily routine, you’ll understand why so many people love keeping it on hand.
Frequently asked questions
What is CircO2?
CircO2 is a quick-dissolve lozenge designed to support the body’s natural nitric oxide levels. Nitric oxide plays a role in energy, circulation, and overall vitality.
How do I take CircO2?
Simply place one lozenge under your tongue and let it dissolve. Most people take it once per day, but follow the directions on the packaging.
How long does it take to feel a difference?
Every person is different. Some people notice supportive effects within days, while others experience more gradual changes over a few weeks of consistent use.
Is CircO2 safe?
CircO2 is made with natural ingredients and is formulated to support general wellness. If you have medical conditions or are taking medication, consult your healthcare provider before use.
Can women use CircO2?
Yes. CircO2 is suitable for adults of all genders who want natural support for circulation, energy, and vitality.
Can I take CircO2 with other supplements?
In most cases, yes. However, because everyone’s wellness routine is different, it’s always best to check with a healthcare professional.
Do I need a prescription?
No. CircO2 is a dietary supplement and does not require a prescription.
What does the flavor taste like?
CircO2 has a refreshing mint-like taste and dissolves quickly in the mouth, making it easy to take anytime.
How long does one box last?
One box typically contains 30 quick-dissolve tablets, which is a one-month supply if used daily.
What is your refund policy?
Your order is covered by a 90-day “Down to the Last Lozenge” satisfaction guarantee. If you’re not completely satisfied, you can return the box — even if it's empty — for a full refund.
Can I take CircO2 if I’m over 50?
Yes. Many adults in their 40s, 50s, and beyond choose CircO2 for daily wellness support and vitality.
Do I need to take it with food?
No. CircO2 is a quick-dissolve lozenge and can be used anytime — before meals, after meals, or between activities.
Disclaimer:
Affiliate Disclosure:
This website provides general wellness information only and does not offer medical advice, diagnosis, or treatment. The products mentioned, including Nitric Boost, are dietary supplements and are not intended to diagnose, treat, cure, or prevent any disease. Individual results may vary. Always speak with a qualified healthcare professional before using any supplement, especially if you have medical conditions or take medication. This site may include affiliate links, and we may earn a commission at no additional cost to you.
Some links on this site are affiliate links. This means that if you click the link and purchase a product, we may receive a commission at no extra cost to you. We only recommend products we believe may provide value.
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