CircO2 review: what the official page claims, checked against the evidence
The problem CircO2 is meant to help with
The official page says nitric oxide levels drop as people get older. It links that drop to feeling tired, having less stamina, colder hands and feet, memory lapses, blood pressure concerns, less comfort in the joints, and less confidence with intimacy.
That kind of problem can feel very everyday and very frustrating. A person may want to stay active, travel, keep up with hobbies, think clearly in conversations, and feel steady through the day, but instead feel slowed down and worn out.
CircO2 is sold as a nitric oxide supplement in lozenge form for these age-related concerns. Below, we explain what the official page promises and what we could confirm from the page itself.
Summary
CircO2 is a fast-dissolving lozenge sold as a nitric oxide booster. The official page clearly states where it is sold, how the lozenge is meant to be used, package prices, and a 90-day money-back policy with return shipping paid by the customer. The page also names ingredients such as beet root powder, hawthorn berry, L-citrulline, vitamin B12, vitamin C, and magnesium. But the page does not provide independent evidence on the page to confirm major benefit claims like better energy, memory, blood pressure support, stamina, or sexual performance.
Opens the seller’s website. Check the current price and refund terms there.
At a glance
- What it is
- A nitric oxide dietary supplement in fast-dissolving lozenge form
- How it is used
- According to the official page, you place a lozenge on your tongue; many people take one in the morning, and the page suggests twice a day for the first week or two
- Main features or ingredients named
- Beet root powder, hawthorn berry, L-citrulline, vitamin B12, vitamin C, and magnesium
- Guarantee or warranty
- 90-day satisfaction guarantee; according to the page, returns within 90 days get a full refund and the customer pays return shipping
- Payment or price
- 1 box $49.95; 3 boxes $44.95 per box ($134.85 total); 6 boxes $41.50 per box ($249.00 total). Lowest stated cost is $41.50 per box.
- Where it is sold
- According to the official page, CircO2 is not available in stores
- Our method
- Document research. We have not used CircO2 ourselves.
The claims, checked
Each claim below is quoted from the official page. See what each result means.
| What the seller says | What we checked | Result |
|---|---|---|
| “Nitric Oxide Levels Jump 200% Higher In Just 20 Minutes” | We looked for independent evidence on the page supporting this result, including the test conditions, comparator, sample details, and where the study was published. The page mentions clinical testing but does not provide enough detail on the page to verify it independently. | Not verified |
| “In clinical testing, this method raised nitric oxide levels 200% within 20 minutes.” | We looked for the clinical testing details, including what was compared against what, how nitric oxide was measured, and who was tested. Those details are not provided on the page text. | Not verified |
| “And it increased blood flow by a staggering 34%.” | We looked for supporting study details on the page, including the comparison group, timing, and test method. The page does not provide enough information to independently verify this figure. | Not verified |
| “CircO2 is not available in stores.” | We checked whether the official page states where it is sold. The page directly says it is not available in stores. | Confirmed |
| “If you are unsatisfied for any reason, return it within 90 days for a full refund.” | We checked the refund terms stated in the offer section. The page repeatedly states a 90-day full refund policy if returned within 90 days. | Confirmed |
| “You only pay return shipping.” | We checked the guarantee text for who covers shipping on returns. The page says the customer pays return shipping. | Confirmed |
See the full offer, guarantee and prices on the seller’s website.
What CircO2 is
CircO2 is sold as a nitric oxide supplement. According to the official page, it comes as a fast-dissolving lozenge that you place on your tongue rather than swallow like a regular pill.
The seller says this format matters because nitric oxide production starts in the mouth. The page says the lozenge mixes with bacteria on the tongue and starts nitric oxide production within minutes.
That is the product's main idea. But the page does not give enough independent detail on its testing to confirm the size of the promised effects.
Ingredients or Main features
The official page names several ingredients and says they are included to support nitric oxide production, blood flow, energy, and circulation.
- Beet Root Powder
- Hawthorn Berry
- L-Citrulline
- Vitamin B12
- Vitamin C
- Magnesium
- Fast-dissolving lozenge delivery
What the evidence actually is
The official page mentions MIT scientists, clinical testing, and a footnote marker for the claim that nitric oxide levels jump 200% higher in 20 minutes. But in the text provided, there is no full study citation, no journal reference, no sample size, and no clear description of what the product was compared against.
The page also makes many broad benefit claims about energy, memory, blood pressure, sexual performance, mobility, and sleep. Those may be seller claims, but they are not independently confirmed by evidence shown on the page.
The page includes customer reviews and a compensated endorsement disclosure for Dr. Greg Eckel. Customer comments are not the same as independent proof, and the page itself says those results may not reflect the typical purchaser's experience.
Buying, shipping and refunds
According to the official page, CircO2 is sold directly online and is not available in stores. The listed package options are 1 box for $49.95, 3 boxes for $134.85 total at $44.95 per box, and 6 boxes for $249.00 total at $41.50 per box.
The page says the 3-box and 6-box packages include free shipping. It also says every purchase is protected by an ABN 100% Satisfaction Guarantee.
The refund policy on the page says you can return the product within 90 days for a full refund, and that you pay return shipping. The page also describes this as a down to the last lozenge guarantee, including even if the box is empty.
Who might consider it, and who should not start here
CircO2 may interest adults who are specifically looking for a nitric oxide supplement in lozenge form and who want a clear refund policy before buying. It may also appeal to people who prefer a direct-order product rather than shopping in stores.
Still, this should not be the first step for someone with new or worsening fatigue, circulation problems, memory changes, blood pressure concerns, chest symptoms, or sexual function changes. Those issues can have many causes and deserve proper medical advice.
The official page itself says people who have low blood pressure should consult with their physician before taking CircO2.
See a doctor or qualified professional first if you notice
- New chest pain, shortness of breath, or fainting
- Blood pressure readings that are high, very low, or changing a lot
- New memory problems, confusion, or major changes in thinking
- Leg pain, swelling, numbness, or cold limbs that do not improve
- Sexual function changes that are sudden or keep happening
Our take
CircO2 has clear purchase terms and a stated 90-day refund policy, which lowers the risk of trying it. Still, the main benefit claims on the official page are mostly marketing claims rather than independently verified evidence shown there. The most practical move is to read the ingredient list and refund terms closely, and ask a clinician first if you have low blood pressure or ongoing circulation concerns.
Opens the seller’s website. ClearPick is independent and not affiliated with the seller. Check the current price and refund terms there before buying.
Questions
Is CircO2 legit?
CircO2 appears to be a real product offer with stated ingredients, pricing, and a 90-day refund policy on the official page. But that does not mean its main performance claims are independently proven on the page. The clearest confirmed points are the purchase terms and refund terms.
Does CircO2 really boost nitric oxide and energy?
According to the official page, CircO2 is meant to raise nitric oxide levels and support energy, stamina, circulation, memory, and sexual performance. However, the page text provided does not include enough independent study detail to verify the size of those promised effects.
How is CircO2 used?
The official page says CircO2 comes as a lozenge that you place on your tongue and let dissolve completely if possible. It also says many people take one in the morning, and suggests taking it twice a day for the first week or two.
How do you buy CircO2?
According to the official page, CircO2 is not sold in stores and is ordered online. The page lists 1-box, 3-box, and 6-box options, with free shipping on the 3-box and 6-box packages.
What is the CircO2 refund policy?
The official page says purchases are covered by a 90-day satisfaction guarantee. If you are unsatisfied for any reason, the page says you can return it within 90 days for a full refund, and you pay return shipping.
Did ClearPick test CircO2?
No. This review is based on document research of the official page text. We have not used CircO2 ourselves.
Sources
- CircO2 official website. https://www.advancedbionutritionals.com/DS24/Nitric-Oxide-Supplements/Superhuman-At-70/HD.htm. Checked October 6, 2026.
- CircO2 affiliate terms. https://digistore24.advancedbionutritionals.com/circo2-5. Checked October 6, 2026.
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