Longevity medicine: what is proven, what is promising and what is hype

Start with what has the best evidence

Before any pill or injection, the interventions with decades of supporting data are unglamorous. The CDC recommends that older adults get about 150 minutes of moderate aerobic activity each week, muscle-strengthening work on at least two days and regular balance training. Add consistent sleep, not smoking, limiting alcohol and keeping blood pressure, blood sugar and cholesterol in check, and you have covered the factors most strongly tied to a longer, healthier life.

We avoid the phrase anti-aging because it promises more than any current medicine can deliver. Our aim is healthspan: more years of feeling well and staying capable.

NAD+: what it is and what injections can do

NAD+ is a molecule found in every cell that more than 400 enzymes depend on for energy metabolism and repair. Your body makes it from vitamin B3 forms such as niacin and nicotinamide, and levels appear to decline with age in some tissues. That observation drives interest in raising NAD+ with injections or precursor supplements such as nicotinamide riboside (NR) and NMN.

Human research so far shows that precursors can raise NAD+ levels in blood, but evidence that this translates into better energy, cognition or longer life is limited and mixed. NAD+ injections prescribed through HealifyMD are compounded, so they are not FDA-approved and have not been reviewed by the FDA for safety or effectiveness. Common complaints during or after an injection include flushing, nausea, cramping and chest tightness, which often ease when the dose is given more slowly.

NR versus NMN

Both are precursors your body can convert to NAD+. NR is sold as a dietary supplement. In November 2022, the FDA concluded that NMN cannot be legally marketed as a dietary supplement because it had first been studied as a drug, so NMN's supplement status is contested. Regular niacin also raises NAD+ but can cause flushing at higher doses.

Rapamycin: strong animal data, unproven in people

Rapamycin, also called sirolimus, is FDA-approved to prevent kidney transplant rejection and to treat a rare lung disease called lymphangioleiomyomatosis. It extends lifespan in several animal species, which is why longevity researchers are interested, but that effect has not been demonstrated in humans. Using it for aging is off-label.

At transplant doses, sirolimus carries a boxed warning for serious infections and certain cancers, and mouth sores are a common side effect. Lower, intermittent doses used in longevity settings may carry less risk, but long-term human safety data are limited. Monitoring labs, avoiding live vaccines and telling every doctor and dentist you take it are part of using it responsibly.

Methylene blue: a real interaction to respect

Methylene blue is approved as an injectable treatment for methemoglobinemia, a blood disorder. Uses for energy, cognition or longevity are off-label and supported by limited human evidence. The FDA has warned that methylene blue can cause serious serotonin syndrome when combined with certain antidepressants, especially SSRIs and SNRIs, so tell your clinician about every psychiatric medication you take. It also turns urine blue-green, which is harmless. People with G6PD deficiency need testing or caution before using it.

DHEA and pregnenolone

DHEA levels fall with age, but trials of DHEA supplements in older adults have generally shown small or inconsistent benefits. Because supplements are not checked by the FDA for content before sale, the dose on the label may not match what is in the bottle. DHEA can also shift sex hormone levels and lab results, so disclose it if you take it.

How HealifyMD approaches longevity requests

A longevity visit starts with measurement rather than a prescription. Your clinician reviews your history, family risks and a baseline lab panel covering blood sugar, cholesterol-related markers, kidney and liver function and other basics. Often the most valuable finding is an ordinary, treatable risk, such as rising blood pressure or prediabetes, rather than anything exotic.

If you and your clinician decide to try an experimental or off-label option, agree on why, what you will measure and when you will decide whether to continue. Stopping something that is not clearly helping is a good outcome, not a failure.