EVIDENCE DESK / FAQ
Questions, Sorted by Evidence
Direct answers about what each compound is, what researchers measure, and where the record stops.
What is NAD supplement used for?
NAD+-related supplements are generally intended to increase the body’s NAD+ pool, often through precursors such as NMN or NR. Trials show that these precursors can raise blood NAD+ [2][5]. Researchers have also studied walking measures, quality of life, and muscle insulin sensitivity [2][3]. Those endpoints do not establish disease prevention or longer life.
What is the downside of taking NAD+?
The main limitation is uncertainty about translation. Raising NAD+ in blood does not guarantee a useful change in every tissue or a durable clinical benefit. A current review finds human efficacy limited and tissue-specific evidence sparse [1]. Oral NAD+, precursor supplements, and compounded intravenous products are different interventions with different evidence and oversight.
Does NAD+ prove an anti-aging effect?
No. NAD+ biology is linked to processes that change with age, and precursor studies demonstrate biomarker engagement [2][4][5]. The composed human record does not contain a trial showing that NAD+ or its precursors extend human lifespan. Mechanism, biomarker response, and longevity are separate levels of evidence.
What does the MOTS-c peptide do?
MOTS-c participates in mitochondrial stress signaling. Laboratory studies connect it with AMPK, nuclear antioxidant-response genes, and CK2-related muscle effects [8][10][12]. In mice, it has improved measures of physical performance [11]. Controlled human efficacy has not been demonstrated in this corpus.
What are the negative side effects of MOTS-c?
A reliable human adverse-effect profile has not been established because the corpus contains no completed human efficacy or safety trial of administered MOTS-c. That absence should not be mistaken for proof of safety. Product identity, sterility, pharmacokinetics, and human dose-response remain unresolved in research-chemical settings.
Is MOTS-c a human longevity treatment?
No approved human longevity indication is established. Mouse studies report performance and muscle-homeostasis findings [8][11], while human evidence here is an observational association between circulating MOTS-c and risk in a hemodialysis cohort [9]. Neither finding demonstrates that administering MOTS-c lengthens human life.
What is tesamorelin?
Tesamorelin is a synthetic analogue of growth hormone-releasing hormone. It stimulates pulsatile release of endogenous growth hormone and raises IGF-1. It is an approved prescription medicine for reducing excess abdominal fat in adults with HIV-associated lipodystrophy [14], not a generally approved anti-aging therapy.
What does tesamorelin do?
In trials involving adults with HIV-associated lipodystrophy, tesamorelin reduced measures of visceral, trunk, and liver fat and increased lean body mass [13][15]. Longer study showed that visceral fat could return after discontinuation [17]. Those findings are specific to the studied population and endpoints.
Does tesamorelin prove that less belly fat means longer life?
No. Visceral fat is a clinically relevant body-composition measure, but changing it is not the same as directly demonstrating fewer major events or longer survival. Tesamorelin trials establish an effect on selected surrogate endpoints in a defined population [13][15][17]. A lifespan claim would require different evidence.
What is semaglutide used for?
Semaglutide is an approved GLP-1 receptor agonist used across type 2 diabetes, chronic weight management, cardiovascular risk reduction in a defined population, and metabolic liver disease. This desk focuses on published endpoints: weight change [21], major kidney outcomes [19], and major cardiovascular outcomes [20]. It does not offer treatment advice.
How does semaglutide work for weight loss?
Semaglutide activates GLP-1 receptors involved in appetite, satiety, glucose regulation, and stomach emptying. The resulting reduction in food intake is central to weight change. A randomized trial found a substantially larger average weight reduction with semaglutide than placebo [21], while a later head-to-head trial found greater average loss with tirzepatide [18].
Are clinical outcomes the same as lifespan evidence?
No. Cardiovascular and kidney events are more direct than biomarkers because they matter to health and function. Semaglutide trials reduced defined event composites in high-risk populations [19][20]. A lifespan claim is broader and would need evidence designed around survival, long follow-up, and the population to which the claim is applied.