NAD+ Injections and Aging: What If You Never Ran Low?

Every cell in your body runs on a small molecule called NAD+. It helps turn food into energy. It helps repair your DNA. And your body spends it all day, every day.

So here is a question worth a few minutes of your time. What if you never ran low?

In mice, the answer is hard to ignore. Old mice given an NAD+ booster have shown stronger muscles, healthier blood vessels and better fertility. In people, we know the first half of the story: you can raise your NAD+. The second half, whether that slows aging, has not been tested yet.

This article covers both halves. Then it tells you plainly how we think about it at Goprolean, what it costs, and what to ask before you buy NAD+ from anyone.

What NAD+ does, and why aging researchers care

NAD+ is a helper molecule found in every living cell. It takes part in roughly 500 chemical reactions, most of them to do with making energy.

It also gets used up. The enzymes that repair damaged DNA and keep inflammation in check consume NAD+ as they work. The more repair a cell has to do, the more it spends.

Now the part that caught researchers' attention. In mice, NAD+ falls with age. By old age, a mouse has about half the NAD+ of a young one in several tissues. If the same thing happens in people, topping it up might help old cells behave more like young ones. A 2018 review in Cell Metabolism lays out the case.

It is not a closed case. In June 2026 a study in Nature Metabolism measured NAD+ in the blood of people from seven separate groups and found that it did not change with age. Blood is not muscle or brain, and tissue is where NAD+ does its work. So the question is open. That is what makes it interesting.

What happens in mice

The strongest evidence comes from mice. Old mice given compounds the body turns into NAD+ have shown better muscle function, healthier blood vessels and improved fertility. In one study, mice started on a booster late in life lived nearly 5% longer.

Not every study agrees. A US government program that tests longevity compounds in three laboratories at once found no extra lifespan from the booster it tested.

One detail is worth remembering for later. In these studies the mice got their booster every day, in food or drinking water, often for months.

And a mouse is not a person. Asked why he takes none of these compounds himself, a senior scientist at the National Institute on Aging answered, "Because I'm not a mouse."

What we know in people so far

Step one works. In a 2017 trial, 120 healthy adults aged 60 to 80 took a booster capsule or a placebo every day for eight weeks. Blood NAD+ rose by about 40% on the standard dose and about 90% on the double dose, with no serious side effects reported.

Step two is the open part. Does a higher number in the blood change how a muscle, a heart or a brain ages? Reviews of the human trials say the benefits seen so far are limited. And no controlled trial has yet tested NAD+ given directly, by drip or by injection, against any measure of aging.

That is not a no. It is a not yet.

Why nobody has run the trial that would settle it

A lifespan study in mice takes about three years. The same study in people would take most of a century.

To show that anything makes humans live longer, you would need thousands of volunteers, half of them on a placebo, followed for decades. Nobody stays on a placebo for forty years, and few funders will wait that long for an answer.

There is a paperwork problem too. Aging is not classed as a disease, so there is no standard route for testing a treatment against it.

Researchers have two workarounds. They can count diseases in place of deaths. That is the plan for the TAME trial, which would follow more than 3,000 people aged 65 to 79 on the diabetes drug metformin for six years. The design is ready. The funding is not. Or they can measure a marker, such as a blood test. That gives an answer in weeks, but a marker can move without the outcome moving.

This is why honest answers about longevity sound unsatisfying. "Not proven" does not mean "disproven". It means the proof takes longer than the question has existed.

The same is true of every longevity claim you will read, including the ones about GLP-1 medications. We cover those in Do GLP-1 Medications Slow Aging?

Capsules, drips or injections: does the route matter?

There are three ways people try to raise NAD+. They are not the same product, and they do not have the same evidence behind them.

One piece of biology explains why the route matters. NAD+ is a large molecule, and most cells cannot take it in whole. The body breaks it into smaller pieces outside the cell, and the cell rebuilds NAD+ from those pieces.

One large dose, or a little every day?

Look closely at the one published drip study. Eight men received 750 mg of NAD+ through a vein over six hours. Three more received salt water for comparison.

For the first two hours, about a third of the dose, nothing in the blood changed. The body took up or broke down the NAD+ as fast as it arrived. After that it fell behind. By the end of the drip, NAD+ in the blood had risen several-fold, and so had the amount of NAD+ passing out in the urine.

That is what one large dose looks like: a level far above normal for a few hours, with some of the dose leaving the body in the urine.

Now ask the common-sense question. Your cells use NAD+ and rebuild it continuously, every day of your life. Is a need like that better met by one large amount now and then, or by a small amount on a regular schedule?

The published studies cannot answer that, because none of them tested it. The drip study measured one large dose on one day. The capsule trials measured a precursor, not NAD+ itself. Nobody has published what a small injection of NAD+ does, day after day.

What we think

What NAD+ costs

"NAD+" on a label can mean four different products, at very different prices.

Notice the drip. A single session often costs more than a month of injections.

What does $99 a month buy?

You will see NAD+ injections advertised for $99 a month, and sometimes less. We went looking for what that buys. We came back with questions.

• How much NAD+ is in the vial? One 2026 comparison of eight online sellers could report the amount for only two of them.
• What is the price in month two? One $99 offer we read is $99 for the first month and $199 after that. Others quote their lowest price only if you pay for a year up front.
• Which pharmacy makes it, and from what grade of ingredient? The low-price offers we read did not name the pharmacy or the grade.

That last question is the one that matters. In October 2024 the FDA warned about patients who had severe chills, shaking and vomiting after NAD+ injections made from an ingredient graded for food, not for injection. In 2025 an NAD+ product for injection was recalled over contamination.

Maybe a $99 injection is every bit as good. Maybe. You cannot tell from the price, and neither can we. We can only imagine what $99 a month buys. This is something you inject, so it is worth asking before it goes under your skin.

Why ours is $299

Our NAD+ injection is $299 for a one-month supply. No membership fee. No consultation fee. Longer plans cost the same per month.

Here is what that pays for. A licensed physician reviews your medical history before anything is prescribed. A licensed 503A compounding pharmacy prepares your prescription and ships it to you. If the physician decides NAD+ is not right for you, you are refunded in full.

We did not set out to be the cheapest NAD+ on the internet. For something you inject, cheapest was never the goal. We think $299 is the right price for doing this carefully.

Is it safe?

Injected NAD+ is a compounded medication. It is not FDA-approved, and the FDA has not reviewed it for safety or effectiveness.

Reported side effects include soreness where the injection goes in, warm flushing, headache, nausea and tiredness. The long-term effects of regular injections have not been studied.

One question is still open. Because growing cells use NAD+, some researchers have asked whether raising it could help a tumor as well as a healthy cell. In one mouse study, a booster increased growths in mice bred to develop pancreatic cancer. There are no human data. If you have or have had cancer, raise it with the physician reviewing your intake.

Five questions to ask anyone selling NAD+

You do not have to decide whether NAD+ slows aging. Nobody can yet. You can decide how to approach an open question sensibly. Ask these of any provider, including us.

1. Which form is this, and what has actually been measured for that form?
2. Who prescribes it, and does a physician review my history first?
3. Which pharmacy prepares it, and from what grade of ingredient?
4. How much NAD+ is in a month's supply, and what will I pay in month two?
5. What will I notice or measure to judge whether it is working, and what would make me stop?

Keep reading: Glutathione Injections: What If You Could Refill Your Master Antioxidant? and Do GLP-1 Medications Slow Aging?

Frequently asked questions

Does NAD+ fall as you get older?

In mice, yes, in several tissues. In people it is less clear. A 2026 study of seven groups of people found that NAD+ in the blood did not change with age. What happens inside human tissues has been measured far less.

Has NAD+ been shown to make people live longer?

No. No study in people has tested that, and a study that could would take decades. In mice, NAD+ boosters have improved health in several studies and lifespan in some.

Are NAD+ injections better than capsules?

Nobody has compared them. Capsules of NAD+ precursors have raised blood NAD+ in several human trials. Injections under the skin have not been measured in published human studies. We think a small, regular injection is the most sensible way to supply NAD+ itself, and we explain why above. That is our view, not a proven result.

Is one large NAD+ drip better than small, regular injections?

Nobody has compared them in people. In the one published drip study, NAD+ in the blood rose several-fold by the end of a six-hour drip, and so did the amount passing out in the urine. We think a small, regular supply makes more sense for a molecule the body uses every day.

How much do NAD+ injections cost?

Online, NAD+ injections are advertised from about $93 to $299 a month. Goprolean charges $299 for a one-month supply, with no membership fee and no consultation fee. A drip at a clinic usually costs several hundred dollars a session.

Why is Goprolean's NAD+ $299 a month when some sellers charge $99?

A low price does not tell you how much NAD+ is in the vial, what the price becomes after the first month, or which pharmacy made it and from what grade of ingredient. Our $299 covers a licensed physician's review of your history and a prescription prepared by a licensed 503A compounding pharmacy. We did not set out to be the cheapest.

Is injected NAD+ approved by the FDA?

No. It is a compounded medication prepared by a pharmacy for an individual prescription. The FDA has not reviewed it for safety or effectiveness.

Is it safe?

Short-term side effects reported include injection-site soreness, flushing, headache and nausea. Long-term safety has not been studied. The harm documented so far came from injections made with an ingredient not graded for injection, which is why the pharmacy matters.

Sources

• Therapeutic Potential of NAD-Boosting Molecules: The In Vivo Evidence, Rajman, Chwalek and Sinclair, Cell Metabolism, 2018.
• Repeat dose NRPT increases NAD+ levels in humans safely and sustainably, Dellinger and others, npj Aging and Mechanisms of Disease, 2017.
• A Pilot Study Investigating Changes in the Human Plasma and Urine NAD+ Metabolome During a 6 Hour Intravenous Infusion of NAD+, Grant and others, Frontiers in Aging Neuroscience, 2019. Funded by a group that runs NAD+ clinics.
• 17-a-estradiol late in life extends lifespan in aging UM-HET3 male mice; nicotinamide riboside and three other drugs do not affect lifespan in either sex, Harrison and others, Aging Cell, 2021. The three-laboratory mouse lifespan program.
• Trętowicz and others, Nature Metabolism, 2026. Blood NAD+ and age across seven groups of people.
• NAD+ precursor supplementation in human ageing: clinical evidence and challenges, Nature Metabolism, 2025 (abstract).
• Science vs. Hype: The Unproven Promise of NAD+ IV Therapy, Science-Based Medicine, 2026.
• FDA reminds compounders to use ingredients suitable for sterile compounding, US Food and Drug Administration, October 2024.
• The TAME Trial, American Federation for Aging Research.
• A Fountain of Youth Pill? Sure, If You're a Mouse, KFF Health News, 2019.
• Cancer Research Points to Key Unknowns about Popular Antiaging Supplements, Scientific American, 2019.
• Prices: published price comparisons of online NAD+ sellers and infusion centers (August 2026) and sellers' own listings (October 2026).